Carboxylate, carboxylic acid generator, resin, resist composition, and method for producing resist pattern

Abstract

To provide a carboxylic acid generator, a resist composition and the like which allow a resist pattern having good line edge roughness to be produced.SOLUTION: There are provided: a carboxylic acid generator and the like containing a carboxylate represented by formula (I); and a resist composition. [X represents an S atom or an I atom; m10 represents 1 when X is an S atom, and m10 represents 0 when X is an I atom; R1A and R1B each represent -X1-R10 or the like, X1 represents -CO-O-, -O-CO- or the like, and R10 represents an acid-stable hydrocarbon group; R4-R9 each represent a halogen atom, a hydrocarbon group or the like; X0 represents a single bond or a hydrocarbon group; and Rbb1 represents an H atom, a halogen atom or the like.]SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a carboxylate, a carboxylic acid generator, a resin, a resist composition, and a method for producing a resist pattern. [Background technology]

[0002] Patent Document 1 describes a resist composition that contains a resin that includes a structural unit derived from a carboxylate represented by the following formula. TIFF2025026391000001.tif2651 [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-037834 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention provides a carboxylate that forms a resist pattern that has better line edge roughness (LER) than a resist pattern formed with a resist composition that contains a resin that includes a structural unit derived from the above carboxylate. [Means for solving the problem]

[0005] The present invention includes the following inventions. [1] A carboxylic acid generator containing a carboxylate represented by formula (I) or a structural unit represented by formula (IP). TIFF2025026391000002.tif92129 [In formula (I) and formula (IP), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1. When X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0. R 1A and R 1Bare each independently *-X 1 -R 10 , *-X 1 -L 11 -X 2 -R 10 * stands for R 4 is bonded to a benzene ring or R 7 represents the bonding site with the benzene ring to which it is attached. X 1 and X 2 are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (wherein * represents a benzene ring or L 11 ) represents the binding site with. L 11 represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. R 10 represents an acid-stable hydrocarbon group. R 4 represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, and -CH2- contained in the hydrocarbon group optionally being replaced by -O-, -S-, -CO-, -SO- or -SO2-. R 7 , R 8 and R 9 each independently represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. When X is a sulfur atom, R 7 and R 8 or R 8 and R 9 Combined, S + The R forming the ring may form a ring containing 7 and R 8 or R 8 and R 9 is S +and -CH2- may be a single bond formed between two benzene rings that are bonded to each other. -CH2- contained in the ring may be replaced with -O-, -S-, -CO-, -SO- or -SO2-. m1A represents an integer of 0 to 5, and when m1A is 2 or more, a plurality of R 1A may be the same or different from each other. m1B represents an integer of 0 to 4, and when m1B is 2 or more, a plurality of R 1B may be the same or different, provided that either m1A or m1B is an integer of at least 1. m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R 4 may be the same or different, and satisfy the relationship 0≦m1A+m4≦5. m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R 7 may be the same or different, and satisfy the relationship 0≦m1B+m7≦4. m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R 8 may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R 9 may be the same or different from each other. X 0 represents a single bond or a hydrocarbon group having 1 to 72 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. R bb1 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X 10 is a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR 3 -**, *-NR 3 -CO-O-**, *-O-CO-NR 3 -** or *-Ax-Ph-Ay-**. R 3represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. * and ** represent binding sites, * represents R bb1 represents the bonding site with the carbon atom to which it is bonded. L 10 represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-.] [2] R 10 The carboxylic acid generator according to [1], wherein the acid-stable hydrocarbon group is a group represented by formula (3a): TIFF2025026391000003.tif2057 [In formula (3a), R 1a and R 2a each independently represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, or R 1a and R 2a are bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. R 3a represents a hydrogen atom or R 1a and R 2a and R 3a are bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. * denotes a binding site.] [3] m1A is an integer from 1 to 3, and R 1A But -O-CO-OR 10 Or -OL 11 -CO-OR 10 The carboxylic acid generator according to [1] or [2], [4]X 0 is a single bond, an aliphatic hydrocarbon group having 1 to 72 carbon atoms, or a hydrocarbon group having 6 to 72 carbon atoms including an aromatic hydrocarbon group having 6 to 36 carbon atoms, The carboxylic acid generator according to any one of [1] to [3], wherein the aliphatic hydrocarbon group and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the aliphatic hydrocarbon group, the aromatic hydrocarbon group and the hydrocarbon group may have a substituent. [5]X 0 is an open chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, a group in which an open chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 36 carbon atoms are combined, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a group in which an aromatic hydrocarbon group having 6 to 36 carbon atoms and an open chain hydrocarbon group having 1 to 18 carbon atoms are combined, The chain hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group, The carboxylic acid generator according to any one of [1] to [4], wherein -CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. [6]X 0 but, an alkanediyl group having 1 to 6 carbon atoms; A cycloalkanediyl group having 5 to 6 carbon atoms, an adamantanediyl group, a norbornanediyl group, a phenylene group, COO - and a cycloalkanediyl group, adamantanediyl group, norbornanediyl group or phenylene group having 5 to 6 carbon atoms bonded to the alkanediyl group; or COO - a polycyclic alicyclic hydrocarbon group in which a cycloalkanediyl group, adamantanediyl group or norbornanediyl group having 5 to 6 carbon atoms is bonded to a cycloalkanediyl group having 5 to 8 carbon atoms in a spiro bond; The carboxylic acid generator according to any one of [1] to [5], wherein -CH2- contained in the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group and the norbornanediyl group may be replaced by -O- or -CO-, and the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group, the norbornanediyl group and the phenylene group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group. [7]X 10 is a single bond or a group represented by the formula (X 10 -1)~Formula(X 10 -10). TIFF2025026391000004.tif43162[Formula(X 10 -1)~Formula(X 10 -10) Medium, * and ** are binding sites, * is R bb1 represents the bonding site with the carbon atom to which it is bonded. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents an integer of 0 to 4. X 20 is -O- or -NR 3 - represents. R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.] [8]X 10 is a single bond or a group represented by the formula (X 10 -1'), expression (X 10 -3')~expression(X 10 -8') and formula (X 10 -10')。

[0023] The carboxylic acid generator according to any one of [1] to [7], wherein the carboxylic acid generator is a group represented by any one of [1] to [7]. TIFF2025026391000005.tif47151[Formula(X 10 -1'), expression (X 10 -3')~expression(X 10 -8') and formula (X 10 -10') medium, * and ** are binding sites, * is R bb1 represents the bonding site with the carbon atom to which it is attached. [9]X 10 is a single bond or a group represented by the formula (X 10 -1'), expression (X 10 -5'), expression (X 10 -6') and formula (X 10 -10')。 [8] The carboxylic acid generator according to claim 8, wherein the carboxylic acid generator is a group represented by any one of the following formulas:

[10] L 10 is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms and a cyclic hydrocarbon group having 3 to 18 carbon atoms, The carboxylic acid generator according to any one of [1] to [9], wherein the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the alkanediyl group and the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-.

[11] A resist composition comprising the carboxylic acid generator according to any one of [1] to

[10] .

[12] A carboxylate represented by formula (I), and a resin that includes a structural unit (a1) having an acid labile group.

[13] A resin containing a structural unit represented by formula (IP), The resist composition according to

[11] , wherein the resin comprising the structural unit represented by formula (IP) further comprises a structural unit (a1) having an acid labile group.

[14] The resist composition according to

[13] , further comprising a carboxylate represented by formula (I).

[15] The resist composition according to any one of

[12] to

[14] , wherein the structural unit (a1) having an acid labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). TIFF2025026391000006.tif43144 [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or *-O-(CH2) k1 represents --CO--O--, k1 represents an integer of 1 to 7, and * represents a bonding site with --CO--. R a01 , R a4 and R a5 each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 , R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, and the alkyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom. m1' represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. TIFF2025026391000007.tif31120[In formula (a1-4), R a1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a17represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a11 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group is -O-, -CO- or -NR a18 - may be replaced. R a18 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a1 represents a single bond or -CO-. R a34 and R a35 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -CO- to which they are bonded, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. na1 represents an integer of 1 to 5, and when na1 is 2 or more, the groups in the multiple parentheses may be the same or different. na11 represents an integer of 0 to 4. When na11 is 2 or more, multiple R a17 may be the same or different from each other. mc represents an integer from 0 to 2. TIFF2025026391000008.tif4558[In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. Z a1 is a single bond or -(CH2) h3 -CO-L 54-, h3 represents an integer of 1 to 4, * represents L 51 It represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-. s1 represents an integer of 1 to 3. s1' represents an integer of 0 to 3. TIFF2025026391000009.tif3479[In formula (a1-6), R a61 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a62 , R a63 and R a64 each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a62 and R a63 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are attached. X a61 is a single bond, -CO-O-* or -CO-NR 5 -*, where * represents the bonding site with Ar, and R 5 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X a62 is a single bond, *-OL a61 -or*-CO-OL a62 -, * represents the bonding site with Ar, L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.]

[16] The resist composition according to any one of

[12] to

[15] , wherein the resin comprising the structural unit (a1) having an acid labile group further comprises a structural unit represented by formula (a2-A): TIFF2025026391000010.tif31127[In formula (a2-A), Ra2 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a27 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group is -O-, -CO- or -NR a28 - may be replaced. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a2 represents a single bond or -CO-. nA2 represents an integer of 1 to 5. When nA2 is 2 or more, the groups in the multiple parentheses may be the same or different. na21 represents an integer of 0 to 4. When na21 is 2 or more, a plurality of R a27 may be the same or different from each other. mc represents an integer from 0 to 2.

[17] Further comprising an acid generator, The resist composition according to any one of

[11] to

[16] , wherein the acid generator includes a salt represented by formula (B1). TIFF2025026391000011.tif1395[In formula (B1), L b1 represents a single bond or an (nb1+1)-valent hydrocarbon group which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. L b2represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. nb1 represents an integer of 1 to 6. When nb1 is 2 or more, the groups in the multiple parentheses may be the same or different. Z + represents an organic cation.

[18] (1) A step of applying the resist composition according to any one of

[11] to

[17] onto a substrate; (2) A step of drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the heated composition layer; A method for producing a resist pattern comprising the steps of:

[19] A carboxylate represented by the above formula (I).

[20] R 10 The carboxylate according to

[19] , wherein the acid-stable hydrocarbon group is a group represented by the above formula (3a).

[21] m1A is an integer from 1 to 3; R 1A But -O-CO-OR 10 Or -OL 11 -CO-OR 10 The carboxylate according to

[19] or

[20] ,

[22] X 0 is a single bond, an aliphatic hydrocarbon group having 1 to 72 carbon atoms, or a hydrocarbon group having 6 to 72 carbon atoms including an aromatic hydrocarbon group having 6 to 36 carbon atoms, The carboxylate according to any one of

[19] to

[21] , wherein the aliphatic hydrocarbon group and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the aliphatic hydrocarbon group, the aromatic hydrocarbon group and the hydrocarbon group may have a substituent.

[23] X 0 is an open chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, a group in which an open chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 36 carbon atoms are combined, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a group in which an aromatic hydrocarbon group having 6 to 36 carbon atoms and an open chain hydrocarbon group having 1 to 18 carbon atoms are combined, The chain hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group, The carboxylate according to any one of

[19] to

[22] , wherein -CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-.

[24] X 0 but, an alkanediyl group having 1 to 6 carbon atoms; A cycloalkanediyl group having 5 to 6 carbon atoms, an adamantanediyl group, a norbornanediyl group, a phenylene group, COO - and a cycloalkanediyl group, adamantanediyl group, norbornanediyl group or phenylene group having 5 to 6 carbon atoms bonded to the alkanediyl group; or COO - a polycyclic alicyclic hydrocarbon group in which a cycloalkanediyl group, adamantanediyl group or norbornanediyl group having 5 to 6 carbon atoms is bonded to a cycloalkanediyl group having 5 to 8 carbon atoms in a spiro bond; The carboxylate according to any one of

[19] to

[23] , wherein -CH2- contained in the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group and the norbornanediyl group may be replaced by -O- or -CO-, and the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group, the norbornanediyl group and the phenylene group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group.

[25] X 10 is a single bond or the above formula (X 10 -1)~Formula(X 10 -10).

[26] X 10 is a single bond or the above formula (X 10 -1'), expression (X 10 -3')~expression(X 10 -8') and formula (X 10 -10').

[27] X 10 is a single bond or the above formula (X 10 -1'), expression (X 10 -5'), expression (X 10 -6') and formula (X 10 -10').

[28] L 10 is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms and a cyclic hydrocarbon group having 3 to 18 carbon atoms, The carboxylate according to any one of

[19] to

[27] , wherein the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the alkanediyl group and the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-.

[29] A resin containing a structural unit represented by the above formula (IP). Effect of the Invention

[0006] By using a resist composition that uses a carboxylate of the present invention, a resist pattern with excellent line edge roughness (LER) can be produced. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] In this specification, "(meth)acrylic monomer" means "at least one of acrylic monomer and methacrylic monomer". The expressions "(meth)acrylate" and "(meth)acrylic acid" have the same meaning. In the group described in this specification, both a straight chain structure and a branched structure may be used. When -CH2- contained in a hydrocarbon group or the like is replaced with -O-, -S-, -CO- or -SO2-, the same example applies to each group, and the number of carbon atoms before the replacement is the number of carbon atoms of the hydrocarbon group or the like. "Combined group" means a group in which two or more of the exemplified groups are bonded, and the valence of these groups may be appropriately changed depending on the bond form. "Derived from" or "derived from" refers to a polymerizable C=C bond contained in the molecule becoming a -CC- group (single bond) by polymerization. When stereoisomers exist, all stereoisomers are included. Depending on the number of substituents and the like, hydrogen atoms in each group may be replaced with bond sites at any position and number. The number of carbon atoms in a substituent is not included in the number of carbon atoms of the substituted group. An acid labile group means a group that, when contacted with an acid (e.g., trifluoromethanesulfonic acid, etc.), the leaving group is eliminated to form a hydrophilic group (e.g., a hydroxyl group or a carboxyl group, etc.). A base labile group means a group that, when contacted with a base (e.g., trimethylamine, etc.), the leaving group is eliminated to form a hydrophilic group (e.g., a carboxyl group or a hydroxyl group, etc.). In this specification, the term "solids content of a resist composition" refers to the sum of the components excluding the solvent (E), which will be described later, from the total amount of the resist composition.

[0008] [Carboxylic acid salt represented by formula (I)] The present invention relates to a carboxylate represented by formula (I) (hereinafter sometimes referred to as "carboxylate (I)" or "salt (I)"). In a salt (I), the side having a positive charge is sometimes called a "cation (I)" and the side having a negative charge is sometimes called an "anion (I)".

[0009] [Cation (I)] The cation (I) of the salt represented by formula (I) is a cation represented by formula (IC). TIFF2025026391000012.tif5295 [In formula (IC), all symbols have the same meaning as in formula (I)]

[0010] R 1A and R 1B X in 1 is preferably *-CO-O-, *-O- or *-O-CO-O- (* represents a bonding site to the benzene ring), and more preferably *-O- or *-O-CO-O-. R 1A and R 1B X in 2 is *-CO-O-, *-O-CO- or *-O-CO-O- (* is L 11 It is preferable that the bond is *-CO-O- or *-O-CO-. R 1A and R 1B L included in 11 Examples of the hydrocarbon group in include chain hydrocarbon groups such as an alkanediyl group, monocyclic or polycyclic (including spiro ring) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may be a group consisting of a combination of two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and an alkanediyl group). Examples of the alkanediyl group include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, and a heptadecane-1,17-diyl group; Examples of branched alkanediyl groups include ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. The terminal of the branched alkanediyl group may be an alkyl group such as a methyl group. The chain hydrocarbon group may have 1 to 24 carbon atoms, preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 9, still more preferably 1 to 6, and even more preferably 1 to 4. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following groups: The binding site may be any position. TIFF2025026391000013.tif46168Specifically, the alicyclic hydrocarbon group may be a monocyclic divalent alicyclic hydrocarbon group such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, or a cyclooctane-1,5-diyl group. Examples of the divalent alicyclic hydrocarbon group include a cycloalkyl group such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, spirocyclohexane-1,2'-cyclopentane group, and spiroadamantane-2,3'-cyclopentane group, and a polycyclic cycloalkanediyl group such as a spiro ring having a cycloalkyl group bonded to a norbornyl group or an adamantyl group by a spiro bond. The carbon number of the alicyclic hydrocarbon group may be 3 to 24, preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. Examples of the aromatic hydrocarbon group include arylene groups such as a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, etc. The aromatic hydrocarbon group may have 6 to 24 carbon atoms, preferably 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and further preferably 6 to 10 carbon atoms. Examples of the group combining two or more types include a group combining an alicyclic hydrocarbon group with an alkanediyl group, a group combining an aromatic hydrocarbon group with an alkanediyl group, and a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group. In the combination, two or more types of each of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may be combined. In addition, when any group is X 1 Or X 2 may be bound to Examples of groups combining an alicyclic hydrocarbon group and an alkanediyl group include -divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-alkanediyl group-, and -alkanediyl group-divalent alicyclic hydrocarbon group-. Examples of groups combining an aromatic hydrocarbon group and an alkanediyl group include -divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-, and the like. Examples of groups combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group include -aromatic hydrocarbon group-alicyclic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-. L 10 The --CH2-- contained in the hydrocarbon group having 1 to 28 carbon atoms may be replaced by --O--, --S--, --SO2-- or --CO--. L 10 When --CH2-- contained in the hydrocarbon group having 1 to 28 carbon atoms is replaced with --O--, --S--, --SO2-- or --CO--, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the hydrocarbon group. Examples of groups in which -CH2- in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), an oxy group (a group in which -CH2- in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), a thio ... A group in which -CH2- in the alkyl group is replaced with -S-), a sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), an alkylthio group (a group in which -CH2- at any position in an alkyl group is replaced with -S-), an alkylsulfonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -SO2-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -O-C O-), alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -CO-), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -CO-O-), alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced with -O-), alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position in an alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl group (a an alkanediyl group in which -CH2- at any position is replaced with -CO-), an alkanediylcarbonyloxy group (an alkanediyl group in which -CH2-CH2- at any position is replaced with -CO-O-), an alkanediylsulfonyl group (an alkanediyl group in which -CH2- at any position is replaced with -SO2-), an alkanediylthio group (an alkanediyl group in which -CH2- at any position is replaced with -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group,Examples of the aromatic hydrocarbon group include an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a combination of two or more of these groups. Examples of the alkoxy group include alkoxy groups having 1 to 27 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, etc. The number of carbon atoms in the alkoxy group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. The alkylthio group includes an alkylthio group having 1 to 27 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, an octylthio group, a 2-ethylhexylthio group, a nonylthio group, a decylthio group, an undecylthio group, etc. The number of carbon atoms in the alkylthio group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 27 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, and butoxycarbonyl groups. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 28 carbon atoms, such as acetyl, propionyl, and butyryl groups. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 27 carbon atoms, such as acetyloxy, propionyloxy, and butyryloxy groups. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The alkylcarbonyloxy group preferably has 2 to 11 carbon atoms, more preferably 2 to 6 carbon atoms, further preferably 2 to 4 carbon atoms, and even more preferably 2 or 3 carbon atoms. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 27 carbon atoms, such as a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, a butylsulfonyl group, a pentylsulfonyl group, a hexylsulfonyl group, an octylsulfonyl group, a 2-ethylhexylsulfonyl group, a nonylsulfonyl group, a decylsulfonyl group, an undecylsulfonyl group, etc. The number of carbon atoms in the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. The alkanediyloxy group includes an alkanediyloxy group having 1 to 27 carbon atoms, such as a methyleneoxy group, an ethyleneoxy group, a propanediyloxy group, a butanediyloxy group, a pentanediyloxy group, etc. The number of carbon atoms in the alkanediyloxy group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. Examples of the alkanediyloxycarbonyl group include alkanediyloxycarbonyl groups having 2 to 27 carbon atoms, such as methyleneoxycarbonyl group, ethyleneoxycarbonyl group, propanediyloxycarbonyl group, butanediyloxycarbonyl group, etc. Examples of the alkanediylcarbonyl group include alkanediylcarbonyl groups having 2 to 28 carbon atoms, such as methylenecarbonyl group, ethylenecarbonyl group, propanediylcarbonyl group, butanediylcarbonyl group, pentanediylcarbonyl group, etc. Examples of the alkanediylcarbonyloxy group include alkanediylcarbonyloxy groups having 2 to 27 carbon atoms, such as methylenecarbonyloxy group, ethylenecarbonyloxy group, propanediylcarbonyloxy group, butanediylcarbonyloxy group, etc. The number of carbon atoms in the alkanediyloxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The alkanediylsulfonyl group includes an alkanediylsulfonyl group having 1 to 27 carbon atoms, such as a methylenesulfonyl group, an ethylenesulfonyl group, a propylenesulfonyl group, etc. The number of carbon atoms in the alkanediylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. The alkanediylthio group includes an alkanediylthio group having 1 to 27 carbon atoms, such as a methylenethio group, an ethylenethio group, a propylenethio group, etc. The number of carbon atoms in the alkanediylthio group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. Examples of the cycloalkoxy group include a cycloalkoxy group having 3 to 27 carbon atoms, such as a cyclohexyloxy group. Examples of the cycloalkylalkoxy group include a cycloalkylalkoxy group having 4 to 27 carbon atoms, such as a cyclohexylmethoxy group. Examples of the alkoxycarbonyloxy group include an alkoxycarbonyloxy group having 2 to 26 carbon atoms, such as a butoxycarbonyloxy group. Examples of the aromatic hydrocarbon group-carbonyloxy group include an aromatic hydrocarbon group-carbonyloxy group having 7 to 27 carbon atoms, such as a benzoyloxy group. Examples of the aromatic hydrocarbon group-carbonyl group include an aromatic hydrocarbon group-carbonyl group having 7 to 28 carbon atoms, such as a benzoyl group. Examples of the aromatic hydrocarbon group-oxy group include an aromatic hydrocarbon group-oxy group having 6 to 27 carbon atoms, such as a phenyloxy group.

[0011] Examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. -O- or -CO- in the groups shown below may be replaced by -S- or -SO2-, respectively. The bonding site may be at any position. TIFF2025026391000014.tif46168

[0012] L 11 The substituents which may be contained in L include a halogen atom and a cyano group. 11 In the case of a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group such as an alkyl group, the chain hydrocarbon group such as an alkyl group can be a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. 11 The -CH2- in the chain hydrocarbon group such as the alkyl group in the formula (I) is replaced with -O-, -CO-, -S- or -SO2-, thereby forming L 11can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, or a sulfonyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L 11 The substituent in is preferably an alkyl group having 1 to 4 carbon atoms, a hydroxyl group or a halogen atom, more preferably an alkyl group having 1 to 4 carbon atoms or a halogen atom, and further preferably a methyl group or a fluorine atom.

[0013] L 11 is preferably an alkanediyl group having 1 to 10 carbon atoms (-CH2- contained in the alkanediyl group may be replaced with -O- or -CO-) or a group combining an alkanediyl group having 1 to 4 carbon atoms with an alicyclic hydrocarbon group having 3 to 12 carbon atoms (-CH2- contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced with -O- or -CO-), more preferably an alkanediyl group having 1 to 6 carbon atoms, even more preferably an alkanediyl group having 1 to 3 carbon atoms, and even more preferably a methylene group.

[0014] R 1A and R 1B R included in 10 The acid-stable hydrocarbon group of R is a group that does not change even when in contact with an acid (e.g., trifluoromethanesulfonic acid). 10 means a group that does not leave, the group containing the group represented by the formula: The acid-stable hydrocarbon group is preferably a group represented by formula (3a) (hereinafter sometimes referred to as "acid-stable hydrocarbon group (3a)"). TIFF2025026391000015.tif2057 [In formula (3a), R 1a and R 2a each independently represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, or R 1a and R 2aare bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. R 3a represents a hydrogen atom or R 1a and R 2a and R 3a are bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. * denotes a binding site.]

[0015] R 1a and R 2a Examples of the hydrocarbon group include chain hydrocarbon groups such as alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, and a nonyl group. The chain hydrocarbon group preferably has 1 to 12 carbon atoms, more preferably 1 to 9 carbon atoms, even more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and even more preferably 1 to 3 carbon atoms. The alicyclic hydrocarbon group may be monocyclic, polycyclic or spirocyclic, and may be saturated or unsaturated. Examples of the alicyclic hydrocarbon group include the groups shown below. The bonding site may be any position. TIFF2025026391000016.tif47169Specific examples include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl, polycyclic cycloalkyl groups such as norbornyl and adamantyl, cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane and spiroadamantane-2,3'-cyclopentane, and spiro rings having a cycloalkyl group bonded to a norbornyl or adamantyl group by spiro. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, a binaphthyl group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and further preferably 6 to 10.

[0016] Examples of groups formed by combining these include groups formed by combining an alicyclic hydrocarbon group, such as a cyclopentylmethyl group or an adamantylmethyl group, with a chain hydrocarbon group, and groups formed by combining an aromatic hydrocarbon group, such as a benzyl group or a phenethyl group, with a chain hydrocarbon group. In the case of a group formed by a combination, two or more of the above groups may be combined, and the above groups may contain groups with different valencies (divalent or trivalent groups (chain hydrocarbon groups, alicyclic saturated hydrocarbon groups, aromatic hydrocarbon groups, etc.)). R 1a and R 2a or R 1a and R 2a and R 3a When the hydrocarbon ring formed by bonding together has an alkyl group, the number of carbon atoms in the alkyl group is excluded from the number of carbon atoms in the hydrocarbon ring. R 1a or R 2a When R is a hydrocarbon group, the number of carbon atoms in the hydrocarbon group is preferably 1 to 16, more preferably 1 to 14, and further preferably 1 to 12. 1a and R 2a or R 1a and R 2a and R 3a When these are bonded to each other to form a hydrocarbon ring, each of the hydrocarbon rings independently preferably has 3 to 24 carbon atoms, more preferably has 3 to 18 carbon atoms, and further preferably has 3 to 16 carbon atoms. R 1a and R 2a or R 1a and R 2a and R 3aExamples of the alkyl group that may be possessed when and are bonded to each other to form a hydrocarbon ring include the same groups as those mentioned above. R 1a and R 2a or R 1a and R 2a and R 3a When and are bonded to each other to form a hydrocarbon ring, examples of the hydrocarbon ring include the rings shown below. The bonding site may be any position. TIFF2025026391000017.tif47169 Also, R 1a and R 2a or R 1a and R 2a and R 3a and -C(R 1a )(R 2a )(R 3a ) include the following groups, etc. * represents a binding site. TIFF2025026391000018.tif27162R 1a and R 2a are each independently a hydrogen atom or a hydrocarbon group having 1 to 14 carbon atoms, or R 1a and R 2a and R are preferably bonded to each other to form a hydrocarbon ring having 3 to 24 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms, and each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, or 1a and R 2a and more preferably bond to each other to form a hydrocarbon ring having 3 to 16 carbon atoms which may have an alkyl group having 1 to 6 carbon atoms.

[0017] R 3a is a hydrogen atom or R 1a and R 2a and R 3a and R are preferably bonded to each other to form a hydrocarbon ring having 3 to 24 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. 1a and R 2a and R 3aand more preferably bond to each other to form a hydrocarbon ring having 3 to 16 carbon atoms which may have an alkyl group having 1 to 6 carbon atoms. When the hydrocarbon ring has an alkyl group, the bonding position of the alkyl group is a carbon atom other than the carbon atom bonded to the oxygen atom or the carbonyl group. m1A is preferably an integer of 0 to 4, more preferably an integer of 0 to 3, even more preferably an integer of 1 to 3, even more preferably 1 or 2, and even more preferably 1. m1B is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, even more preferably 0 or 1, and even more preferably 0. R 1A The bonding position of to the benzene ring is X + The position may be any of o-position, m-position, and p-position with respect to the bonding position of the benzene ring to which X is bonded. + At least one of them is preferably bonded to the o-position or p-position with respect to the bonding position of the benzene ring to which is bonded. R 1B The bonding position of to the benzene ring is X + The bonding position of X may be either o-position, m-position or p-position. + It is preferable that at least one of the bonding positions is bonded to the o-position or m-position. R 1A and R 1B are each independently, -OR 10 , -CO-OR 10 , -O-CO-R 10 , -O-CO-OR 10 Or -OL 10 -CO-OR 10 is preferably -O-CO-R 10 , -O-CO-OR 10 Or -OL 10 -CO-OR 10 More preferably, it is -O-CO-OR 10 Or -OL 10 -CO-OR10 It is even more preferable that:

[0018] R 4 , R 7 , R 8 and R 9 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 4 , R 7 , R 8 and R 9 Examples of the hydrocarbon group having 1 to 36 carbon atoms include chain hydrocarbon groups such as alkyl groups and alkanediyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these. The number of carbon atoms in the hydrocarbon group is preferably 1 to 30, more preferably 1 to 24, and even more preferably 1 to 18. The alkyl group is a straight-chain or branched alkyl group, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. The alkanediyl group is a linear or branched alkanediyl group, such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, or a hexane-1,6-diyl group; and Examples of branched alkanediyl groups include ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. The number of carbon atoms in the chain hydrocarbon group may be 1 to 24, preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 9, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples thereof include the groups shown below. The bonding site may be any position. TIFF2025026391000019.tif46168Specifically, the monocyclic alicyclic hydrocarbon group includes monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl. The polycyclic alicyclic hydrocarbon group includes polycyclic cycloalkyl groups such as decahydronaphthyl, adamantyl, and norbornyl, cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane, and spiroadamantane-2,3'-cyclopentane, and spiro rings having cycloalkyl groups bonded to norbornyl or adamantyl groups by spiro. The carbon number of the alicyclic hydrocarbon group may be 3 to 24, preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, a binaphthyl group, etc. The number of carbon atoms in the aromatic hydrocarbon group may be 6 to 24, preferably 6 to 18, more preferably 6 to 14, and further preferably 6 to 10.

[0019] Examples of groups formed by combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group include a group formed by combining an aromatic hydrocarbon group with a chain hydrocarbon group (for example, an aromatic hydrocarbon group-alkanediyl group-*, an alkyl group-aromatic hydrocarbon group-*, an alkyl group-aromatic hydrocarbon group-alkanediyl group-*, where -CH2- contained in the alkanediyl group and the alkyl group may be replaced by -O-, -CO-, -S-, or -SO2-), a group formed by combining an alicyclic hydrocarbon group with a chain hydrocarbon group (for example, an alicyclic hydrocarbon group-alkanediyl group-*, Examples of such groups include an alkyl group-alicyclic hydrocarbon group-*, an alkyl group-alicyclic hydrocarbon group-alkanediyl group-*, an alkyl group-alicyclic hydrocarbon group-alkanediyl group-*, -CH2- contained in the alicyclic hydrocarbon group, the alkanediyl group and the alkyl group may be replaced with -O-, -CO-, -S- or -SO2-, and a group combining an aromatic hydrocarbon group and an alicyclic hydrocarbon group (for example, an aromatic hydrocarbon group-alicyclic hydrocarbon group-*, an alicyclic hydrocarbon group-aromatic hydrocarbon group-*, -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-). * represents a bonding site. The aromatic hydrocarbon group -alkanediyl group-* includes aralkyl groups such as benzyl group and phenethyl group. Examples of the alkyl group-aromatic hydrocarbon group-* include a tolyl group, a xylyl group, and a cumenyl group. Examples of the alicyclic hydrocarbon group -alkanediyl group-* include cycloalkylalkyl groups such as a cyclohexylmethyl group, a cyclohexylethyl group, a 1-(adamantan-1-yl)methyl group, and a 1-(adamantan-1-yl)-1-methylethyl group. Examples of the alkyl group-alicyclic hydrocarbon group-* include cycloalkyl groups having an alkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl group, and a 2-alkyladamantan-2-yl group. Examples of the aromatic hydrocarbon group-alicyclic hydrocarbon group-* include a phenylcyclohexyl group. Examples of the alicyclic hydrocarbon group-aromatic hydrocarbon group-* include a cyclohexylphenyl group. In addition, in the combination, two or more types of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined, and any of the groups may be bonded to a benzene ring.

[0020] R 4 , R 7 , R 8 and R 9 When -CH2- in the hydrocarbon group represented by the formula (I) is replaced by -O-, -CO-, -S-, -SO-, or -SO2-, the number of carbon atoms before the replacement is regarded as the total number of carbon atoms in the hydrocarbon group. The number of replacements may be one or more. As described above, examples of the group in which -CH2- in the hydrocarbon group is replaced with -O-, -CO-, -S-, -SO- or -SO2- include a hydroxyl group, a thiol group, a carboxyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkylthio group, an alkylsulfyl group, an alkylsulfonyl group, an oxy group, a carbonyl group, a thio group, a sulfyl group, a sulfonyl group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylthio group, an alkanediylsulfyl group, an alkanediylsulfonyl group, a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group in which two or more of these groups are combined. Examples of these replaced groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the carbon number. The alkylsulfyl group includes alkylsulfyl groups having 1 to 35 carbon atoms, such as methylsulfyl group, ethylsulfyl group, propylsulfyl group, butylsulfyl group, pentylsulfyl group, hexylsulfyl group, octylsulfyl group, 2-ethylhexylsulfyl group, nonylsulfyl group, decylsulfyl group, undecylsulfyl group, etc. The number of carbon atoms in the alkylsulfyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. The alkanediylsulfyl group includes an alkanediylsulfyl group having 1 to 35 carbon atoms, such as a methylenesulfyl group, an ethylenesulfyl group, a propylenesulfyl group, etc. The number of carbon atoms in the alkanediylsulfyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0021] In addition, examples of the group in which -CH2- in the alicyclic hydrocarbon group is replaced by -O-, -S-, -SO2-, -SO- or -CO- include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. In addition, among the above groups, groups in which -O- is replaced by -S-, and -CO- is replaced by -SO- or -SO2-, etc. are also included.

[0022] R 4 , R 7 , R 8 and R 9 Examples of the substituent that the hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, and the like. Examples of the halogen atom include the same groups as those mentioned above. R 4 , R 7 , R 8 and R 9 When R is a hydrocarbon group having a halogen atom, 4 , R 7 , R 8 and R 9Examples of the hydrocarbon group having a halogen atom include a chain hydrocarbon group having a halogen atom (such as a haloalkyl group), an alicyclic hydrocarbon group having a halogen atom, and an aromatic hydrocarbon group having a halogen atom. Examples of the alkyl group having a halogen include haloalkyl groups having 1 to 12 carbon atoms, such as fluorinated alkyl groups having 1 to 12 carbon atoms, chlorinated alkyl groups having 1 to 12 carbon atoms, brominated alkyl groups having 1 to 12 carbon atoms, and iodinated alkyl groups having 1 to 12 carbon atoms. Examples of the haloalkyl groups include perfluoroalkyl groups having 1 to 12 carbon atoms (trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, etc.), 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, and iodomethyl group. The number of carbon atoms in the haloalkyl group is preferably 1 to 9, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The -CH2- contained in the haloalkyl group may be replaced by -O- or -CO-, etc., and examples thereof include a haloalkoxy group, a haloalkoxycarbonyl group, a haloalkylcarbonyl group, a haloalkylcarbonyloxy group, etc. Specific examples thereof include a haloalkoxy group having 1 to 11 carbon atoms, a haloalkoxycarbonyl group having 2 to 11 carbon atoms, a haloalkylcarbonyl group having 2 to 12 carbon atoms, a haloalkylcarbonyloxy group having 2 to 11 carbon atoms, etc., and examples thereof include groups in which one or more hydrogen atoms of the above-exemplified groups are replaced by halogen atoms. The hydrocarbon group may have one substituent or multiple substituents. R 4 The bond position of the benzene ring to which X is bonded is + In the benzene ring to which X is attached, + The bonding position of R may be either o-position, m-position or p-position. 4 The benzene ring to which X is attached is + It is preferably bonded to the p-position or m-position, and more preferably bonded to the p-position, relative to the bonding position of the above. m4 is preferably an integer of 0 to 4, more preferably 0, 1, 2 or 3, and further preferably 0, 1 or 2. R 4 The bonding position of to the benzene ring is X + may be at the о-position, m-position, or p-position relative to the bonding position of the benzene ring to which m4 is bonded. When m4 is 1 or 2, at least one R 4 X + is preferably bonded to the p-position or m-position with respect to the bonding position of the benzene ring to which R is bonded. 4 X + is preferably bonded to the o-position or m-position with respect to the bonding position of the benzene ring to which it is bonded. m7 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. R 7 The bonding position of to the benzene ring is X + The bonding position of R may be any of o-position, m-position, or p-position. 7 But X + It is preferably bonded to the o-position or m-position, and more preferably bonded to the m-position, with respect to the bonding position of the above. m8 is preferably an integer of 0 to 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. m9 is preferably an integer of 0 to 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. When at least one of m8 and m9 is an integer of 1 or more, R 8 and / or R 9 The bonding position of to the benzene ring is X + The bonding position of R may be any of o-position, m-position, or p-position. 8 and / or R 9 But X +It is preferably bonded to the m-position or p-position, and more preferably bonded to the p-position, relative to the bonding position of the above. R 4 is preferably a halogen atom or an alkyl group having 1 to 12 carbon atoms which may have a halogen atom (-CH2- contained in the alkyl group may be replaced by -O- or -CO-), more preferably a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the fluorinated alkyl group or the alkyl group may be replaced by -O- or -CO-), and more preferably a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (the fluorinated An alkyl group or -CH2- contained in the alkyl group may be replaced with -O- or -CO-) is more preferable, a fluorine atom, a bromine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-) is even more preferable, and a fluorine atom, an iodine atom, a trifluoromethyl group, a hydroxy group, a methoxy group, a methyl group or a t-butyl group is even more preferable. R 7 , R 8 and R 9are each independently preferably a halogen atom or an alkyl group having 1 to 12 carbon atoms which may have a halogen atom (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), more preferably a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the fluorinated alkyl group or the alkyl group may be replaced with -O- or -CO-), and more preferably a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms ( The alkyl fluoride group or the -CH2- contained in the alkyl group may be replaced with -O- or -CO-), is more preferable, a fluorine atom, a bromine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), is even more preferable, and a fluorine atom, an iodine atom, a trifluoromethyl group, a hydroxy group, a methoxy group, a methyl group or a t-butyl group is even more preferable. In another embodiment, R 8 or R 9 may contain an acid-stable hydrocarbon group, each independently -X 1 -R 10 or -X 1 -L 10 -X 2 -R 10 R 8 or R 9 If R contains an acid-stable hydrocarbon group, 1A or R 1B It is preferable that the acid-stable hydrocarbon group contained in

[0023] Specific examples of the cation represented by formula (IC) include cations represented by formula (IC-1) or formula (IC-2) (hereinafter, these may be referred to as "cation (IC-1)" and "cation (IC-2)", respectively). TIFF2025026391000020.tif48147 [wherein all symbols have the same meanings as defined above.] When X is a sulfur atom and m10=1, R7 and R 8 or R 8 and R 9 Combined, S + In particular, R 8 and R 9 Combined, S + It is preferable that the cation is a cation represented by the formula (IC'). TIFF2025026391000021.tif4398[where, X 7 The symbols other than the above have the same meanings as above. X 7 represents a single bond, -CH2-, -O-, -CO-, -SO-, -SO2- or -S-. X 7 is preferably a single bond, -CH2- or -O-.

[0024] Examples of the cation of the salt (I) include the cations represented by the following formulae (Ic-1) to (Ic-50). TIFF2025026391000022.tif116159

[0025] TIFF2025026391000023.tif246157

[0026] TIFF2025026391000024.tif228157

[0027] TIFF2025026391000025.tif88163

[0028] The anion (I) of the salt represented by formula (I) is an anion represented by formula (IA). TIFF2025026391000026.tif2585 [In formula (IA), all symbols have the same meaning as in formula (I)] In formula (IA), X 0Examples of the hydrocarbon group represented by the formula (I) include aliphatic hydrocarbon groups (chain hydrocarbon groups such as alkanediyl groups, alkenediyl groups, and alkynediyl groups, and alicyclic hydrocarbon groups), aromatic hydrocarbon groups, and groups combining these groups. The -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. In the hydrocarbon group, CO2 - The atom adjacent to is preferably a carbon atom, and in the hydrocarbon group, CO - More preferably, the atom adjacent to is a carbon atom. Examples of the alkanediyl group include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, and a dodecane-1,12-diyl group; Examples of branched alkanediyl groups include ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. Examples of the alkenediyl group include an ethenediyl group, a propenediyl group, an isopropenediyl group, a butenediyl group, an isobutenediyl group, a tert-butenediyl group, a pentenediyl group, a hexenediyl group, a heptenediyl group, an octenediyl group, an isooctenediyl group, and a nonenediyl group. Examples of the alkynediyl group include an ethynediyl group, a propynediyl group, an isopropynediyl group, a butynediyl group, an isobutynediyl group, a tert-butynediyl group, a pentynediyl group, a hexynediyl group, an octynediyl group, and a nonynediyl group. Examples of groups in which -CH2- in an open chain hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), a sulfonyl group (a group in which -CH2- in a methylene group is replaced by - SO2- replaced), oxy group (a group in which -CH2- in a methylene group is replaced with -O-), alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -O-CO-), alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -CO-), alkylcarbonyloxy group (a group in which -CH2 -CH2- is replaced with -CO-O-), alkylthio group (a group in which -CH2- at any position in an alkyl group is replaced with -S-), alkylsulfonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -SO2-), alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced with -O-), alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position in an alkanediyl group is replaced with -O-CO-) , an alkanediylcarbonyl group (a group in which -CH2- at any position in an alkanediyl group is replaced with -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position in an alkanediyl group is replaced with -CO-O-), an alkanediylsulfonyl group (a group in which -CH2- at any position in an alkanediyl group is replaced with -SO2-), and an alkanediylthio group (a group in which -CH2- at any position in an alkanediyl group is replaced with -S-). Examples of the alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, alkylthio group, alkylsulfonyl group, alkanediyloxy group, alkanediyloxycarbonyl group, alkanediylcarbonyl group, alkanediylcarbonyloxy group, alkanediylsulfonyl group, and alkanediylthio group include the same groups as described above. The substitution in the alkenediyl group or alkynediyl group may be any of the substitutions in the alkanediyl group exemplified above, as long as it contains a carbon-carbon double bond or a carbon-carbon triple bond at any position. The chain hydrocarbon group may have 1 to 48 carbon atoms, preferably 1 to 36, more preferably 1 to 24, even more preferably 1 to 18, still more preferably 1 to 12, even more preferably 1 to 9, even more preferably 1 to 6, and even more preferably 1 to 4.

[0029] The alicyclic hydrocarbon group may be monocyclic, polycyclic, or spirocyclic, and may be saturated or unsaturated. Examples of the divalent alicyclic hydrocarbon group include the groups shown below. The bonding site may be any position. TIFF2025026391000027.tif58166Specific examples of monocyclic divalent alicyclic hydrocarbon groups include monocyclic cycloalkanediyl groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, a cyclohexene-3,6-diyl group, and a cyclooctane-1,5-diyl group.Examples of polycyclic divalent alicyclic hydrocarbon groups include polycyclic cycloalkanediyl groups such as a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, a 5-norbornene-2,3-diyl group, an adamantane-1,5-diyl group, and an adamantane-2,6-diyl group. The alicyclic hydrocarbon group has 3 to 48 carbon atoms, preferably 3 to 36, more preferably 3 to 24, still more preferably 3 to 18, still more preferably 3 to 16, and still more preferably 3 to 12. The group in which -CH2- in the alicyclic hydrocarbon group is replaced with -O-, -S-, -CO- or -SO2- may form an ether ring, a ketone ring, a lactone ring, a sultone ring or an acetal ring, and specific examples thereof include the following groups. The bonding site may be any position. TIFF2025026391000028.tif82167The alicyclic hydrocarbon group is preferably a group represented by any one of formulas (y1) to (y11), (y44) to (y48), and (y59) to (y61), and more preferably a group represented by formula (y3), (y4), (y9), or (y11). As the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, a group represented by any of the formulae (y12) to (y20), (y26), (y27), (y30), (y31), (y39) to (y43), and (y49) to (y71) is preferable, and a group represented by any of the formulae (y14), (y15), (y16), (y20), (y26), (y27), (y30), (y31), (y39), (y40), (y42), (y43), (y49) to (y58), and (y62) to (y71) is more preferable.

[0030] Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, etc. The number of carbon atoms in the aromatic hydrocarbon group is, for example, 6 to 48, preferably 6 to 36, more preferably 6 to 24, still more preferably 6 to 18, still more preferably 6 to 14, and still more preferably 6 to 10. Examples of the hydrocarbon group combining two or more types include a group combining an alkanediyl group with an alicyclic hydrocarbon group and / or an aromatic hydrocarbon group, such as -alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-aromatic hydrocarbon group-, -aromatic hydrocarbon group-alkanediyl group-, etc. In addition, in the case of a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with an alkanediyl group, the terminal of the alkanediyl group may be an alkyl group such as a methyl group. X 0 When -CH2- in the hydrocarbon group represented by the formula (I) is replaced by -O-, -S-, -CO-, or -SO2-, the number of carbon atoms before the replacement is the total number of carbon atoms in the hydrocarbon group. 0 When a substituent is bonded to a hydrocarbon group represented by the following formula (I), the number of carbon atoms before substitution is regarded as the total number of carbon atoms in the hydrocarbon group.

[0031] X 0 The hydrocarbon group represented by the following formula may have one or more substituents. X 0 Examples of the substituent that may be substituted include a hydroxy group, a halogen atom, a cyano group, and a nitro group. X 0 When X contains an alicyclic hydrocarbon group or a group in which an aromatic hydrocarbon group and a chain hydrocarbon group are combined, 0 The chain hydrocarbon group bonded to the alicyclic hydrocarbon group or aromatic hydrocarbon group contained in X 0 In addition, X can be regarded as a substituent. 0 X is a group in which -CH2- in the hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO-. 0 can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkylthio group, or an alkylsulfonyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0032] X 0 The hydrocarbon group represented by the formula (I) is preferably an aliphatic hydrocarbon group having 1 to 72 carbon atoms which may have a substituent (-CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-) or a hydrocarbon group having 6 to 72 carbon atoms including an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent; More preferably, it is a chain hydrocarbon group having 1 to 18 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 36 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or a group combining an alicyclic hydrocarbon group having 3 to 36 carbon atoms which may have a substituent and an chain hydrocarbon group having 1 to 18 carbon atoms which may have a substituent (the alicyclic hydrocarbon group -CH2- contained in the hydrogen group may be replaced by -O-, -S-, -CO- or -SO2-, and -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, or a group combining an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent and a chain hydrocarbon group having 1 to 18 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), More preferred are *-chain hydrocarbon group-, *-alicyclic hydrocarbon group-, a group combining *-alicyclic hydrocarbon group and chain hydrocarbon group-, *-alicyclic hydrocarbon group-chain hydrocarbon group-, *-chain hydrocarbon group-alicyclic hydrocarbon group-, a group combining *-alicyclic hydrocarbon group and chain hydrocarbon group-chain hydrocarbon group-, *-chain hydrocarbon group-alicyclic hydrocarbon group-, a group combining *-alicyclic hydrocarbon group and chain hydrocarbon group-chain hydrocarbon group-, *-chain hydrocarbon group-alicyclic hydrocarbon group and chain hydrocarbon group-, *-aromatic hydrocarbon group-, *-chain hydrocarbon group-aromatic hydrocarbon group-, *-aromatic hydrocarbon group-chain hydrocarbon group-, *-alicyclic hydrocarbon group-chain hydrocarbon group-, *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-, *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, *-alicyclic hydrocarbon group and chain hydrocarbon group a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain hydrocarbon group-a chain - ) and More preferably, it is an *-alicyclic hydrocarbon group-, an *-alicyclic hydrocarbon group-chain hydrocarbon group-, an *-chain hydrocarbon group-alicyclic hydrocarbon group-, an *-aromatic hydrocarbon group- or an *-chain hydrocarbon group-aromatic hydrocarbon group-; Even more preferred are *-monocyclic alicyclic hydrocarbon group-, *-polycyclic alicyclic hydrocarbon group-, *-polycyclic alicyclic hydrocarbon group-chain hydrocarbon group-, *-chain hydrocarbon group-polycyclic alicyclic hydrocarbon group-, *-aromatic hydrocarbon group- or *-chain hydrocarbon group-aromatic hydrocarbon group-. In the above groups, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the alicyclic hydrocarbon group, the aromatic hydrocarbon group and the chain hydrocarbon group may have a substituent. * represents -COO - represents the bonding site with the carbon atom of In the above groups, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 36, more preferably 3 to 24, even more preferably 3 to 18, still more preferably 3 to 16, and even more preferably 3 to 12. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 9, still more preferably 1 to 6, and even more preferably 1 to 4. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 36, more preferably 6 to 24, even more preferably 6 to 18, still more preferably 6 to 14, and even more preferably 6 to 10. In the above groups, the alicyclic hydrocarbon group or aromatic hydrocarbon group is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms (-CH2- contained in the group may be replaced by -O-, -S-, -CO- or -SO2-), more preferably a group represented by any of formulas (w1-1) to (w1-28), even more preferably a group represented by any of formulas (w1-1) to (w1-6) and (w1-12) to (w1-26), and even more preferably a group represented by any of formulas (w1-1) to (w1-3), (w1-6), (w1-15) to (w1-17), (w1-22) and (w1-25). TIFF2025026391000029.tif75165 [Formula (w1-1) to formula (w1-28), The -CH2- contained in the group may be replaced by -O-, -S-, -CO- or -SO2-. The binding site may be at any position.] More specifically, the monocyclic alicyclic hydrocarbon group is preferably a cycloalkanediyl group having 5 or 6 carbon atoms (-CH2- contained in the cycloalkanediyl group may be replaced by -O- or -CO-), the polycyclic alicyclic hydrocarbon group is preferably an adamantanediyl group, a norbornanediyl group, an adamantanelactonediyl group, a norbornanelactonediyl group, or a cycloalkanediyl group having 5 or 6 carbon atoms bonded to an adamantanediyl group or a norbornanediyl group via a spiro bond (-CH2- contained in the adamantanediyl group, norbornanediyl group, and cycloalkanediyl group may be replaced by -O- or -CO-), and the aromatic hydrocarbon group is preferably a phenylene group. Here, the -CH2-CH2- contained in the adamantanediyl group and the norbornanediyl group may be replaced by -O-CO-, and the cycloalkanediyl group may be an acetal ring. In the above groups, the chain hydrocarbon group is preferably a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), more preferably a chain hydrocarbon group having 1 to 8 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and even more preferably an alkanediyl group having 1 to 6 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). It is also preferable that the chain hydrocarbon group has a fluorine atom. In the above chain hydrocarbon group and alicyclic hydrocarbon group, the substituent is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or a combination of these, and more preferably a fluorine atom, a hydroxy group, or a perfluoroalkyl group having 1 to 4 carbon atoms. In the above aromatic hydrocarbon group, the substituent is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or a combination of these, and more preferably a fluorine atom, an iodine atom, a hydroxy group, or a perfluoroalkyl group having 1 to 4 carbon atoms. More specifically, X 0 is preferably a single bond, an aliphatic hydrocarbon group having 1 to 72 carbon atoms which may have a substituent (-CH2- contained in the aliphatic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), or a hydrocarbon group having 6 to 72 carbon atoms containing an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent (-CH2- contained in the hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-, and the aromatic hydrocarbon group and the hydrocarbon group may have a substituent), More preferably, it is a single bond, a chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, a group in which a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 36 carbon atoms are combined, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a group in which an aromatic hydrocarbon group having 6 to 36 carbon atoms and a chain hydrocarbon group having 1 to 18 carbon atoms are combined, and even more preferably, it is a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, a group in which an alicyclic hydrocarbon group having 3 to 18 carbon atoms and a chain hydrocarbon group having 1 to 8 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group in which an aromatic hydrocarbon group having 6 to 18 carbon atoms and a chain hydrocarbon group having 1 to 8 carbon atoms are combined. However, the chain hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group, and -CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O- or -CO-. X 0 More preferably, it is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cycloalkanediyl group having 5 to 6 carbon atoms, a norbornanediyl group, an adamantanediyl group, a phenylene group, or a COO -a group consisting of an alkanediyl group having 1 to 6 carbon atoms bonded to the alkanediyl group, and a cycloalkanediyl group, adamantanediyl group, norbornanediyl group or phenylene group having 5 to 6 carbon atoms bonded to the alkanediyl group, or - and a cycloalkanediyl group having 5 to 8 carbon atoms are bonded in a spiro bond to a cycloalkanediyl group having 5 to 8 carbon atoms, and -CH2- contained in the alkanediyl group, cycloalkanediyl group, adamantanediyl group and norbornanediyl group may be replaced by -O- or -CO-, and the alkanediyl group, cycloalkanediyl group, adamantanediyl group, norbornanediyl group and phenylene group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group. X 0 In the above, when -CH2- contained in the cycloalkanediyl group is replaced with -O-, an acetal ring may be formed, and when -CH2- contained in the cycloalkanediyl group, adamantanediyl group and norbornanediyl group is replaced with -O- or -CO-, -CH2-CH2- contained in the cycloalkanediyl group, adamantanediyl group and norbornanediyl group may be replaced with -O-CO- or -CO-O- to form a lactone ring.

[0033] R bb1 The halogen atoms in R 4 ~R 9 The same halogen atoms as those listed in R are included. bb1 The alkyl group which may have a halogen atom is, as far as the upper limit of the carbon number allows, R 4 ~R 9 Examples of the alkyl group and the haloalkyl group include the same alkyl group and the haloalkyl group as those exemplified above. R bb1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, even more preferably a hydrogen atom or a methyl group, and even more preferably a methyl group. X10 is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025026391000030.tif3449[In formula (X10), Ax is R bb1 represents a bond type bonding to the carbon atom to which is bonded, and represents one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. Ay is L 10 , X 0 Or COO - and represents one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents an integer of 0 to 4, and when mx is an integer of 2 or more, multiple Rx's may be the same or different. When either Ax or Ay is a single bond, the other is preferably one or more bonds selected from the group consisting of an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. When either Ax or Ay is an amide bond, -CO-NR 3 A bond represented by - is preferred. R 3 The alkyl group of R bb1 The alkyl groups are the same as those mentioned above. Rx is preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group or an ethyl group. mx is preferably 0, 1 or 2. The bonding position of Ay in the phenylene group is preferably the m-position or p-position relative to the bonding position of Ax, and more preferably the p-position. X 10 For example, the following formula (X 10 -1)~Formula(X10 -10) is a group represented by *. bb1 represents the bonding site with the carbon atom to which L is bonded. 10 , X 0 Or COO - It represents the binding site with TIFF2025026391000031.tif46170[expression(X 10 -1)~Formula(X 10 -10) Medium, *, ** are binding sites, * is R bb1 represents the bonding site with the carbon atom to which it is bonded. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents an integer of 0 to 4. X 20 is -O- or -NR 3 - represents. R 3 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.] Expression(X 10 -1)~Formula(X 10 Specific examples of the group represented by -10) include the following groups. TIFF2025026391000032.tif87163Among them, X 10 is a single bond or a group of the formula (X 10 -1') and formula (X 10 -3')~expression(X 10 -10'), a single bond or a group represented by the formula (X 10 -1'), expression (X 10 -4'), expression (X 10 -5'), expression (X 10 -6') and formula (X 10 -10'), and more preferably a single bond, a group represented by the formula (X 10 -1'), a group represented by the formula (X 10 -5') or a group represented by the formula (X 10 -6') is more preferable.

[0034] L10 Examples of the hydrocarbon group having 1 to 36 carbon atoms include aliphatic hydrocarbon groups (chain hydrocarbon groups and alicyclic hydrocarbon groups such as alkanediyl groups, alkenediyl groups, and alkynediyl groups), aromatic hydrocarbon groups, and the like, and may be a hydrocarbon group formed by combining two or more of these groups.

[0035] Examples of the alkanediyl group include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, and a dodecane-1,12-diyl group; Examples of branched alkanediyl groups include ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. The terminal of the branched alkanediyl group may be a methyl group. Examples of the alkenediyl group include an ethenediyl group, a propenediyl group, an isopropenediyl group, a butenediyl group, an isobutenediyl group, a tert-butenediyl group, a pentenediyl group, a hexenediyl group, a heptenediyl group, an octenediyl group, an isooctenediyl group, and a nonenediyl group. Examples of the alkynediyl group include an ethynediyl group, a propynediyl group, an isopropynediyl group, a butynediyl group, an isobutynediyl group, a tert-butynediyl group, a pentynediyl group, a hexynediyl group, an octynediyl group, and a nonynediyl group. The chain hydrocarbon group preferably has 1 to 12 carbon atoms, more preferably 1 to 9 carbon atoms, even more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and even more preferably 1 to 3 carbon atoms. The divalent alicyclic hydrocarbon group may be any of monocyclic, polycyclic, and spirocyclic. Examples of the divalent alicyclic hydrocarbon group include the groups shown below. The bonding site can be any position. TIFF2025026391000033.tif47168Specific examples of monocyclic divalent alicyclic hydrocarbon groups include monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclohexene-3,6-diyl group, and cyclooctane-1,5-diyl group.Examples of polycyclic divalent alicyclic hydrocarbon groups include polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, 5-norbornene-2,3-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group. The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and further preferably 3 to 12 carbon atoms. Examples of the divalent aromatic hydrocarbon group include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, etc. The aromatic hydrocarbon group preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and further preferably 6 to 10 carbon atoms. Examples of the hydrocarbon group combining two or more types include a group combining an alkanediyl group with an alicyclic hydrocarbon group and / or an aromatic hydrocarbon group, such as -alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-aromatic hydrocarbon group-, -aromatic hydrocarbon group-alkanediyl group-, etc. In addition, in the case of a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with an alkanediyl group, the terminal of the alkanediyl group may be an alkyl group such as a methyl group.

[0036] L 10 The --CH2-- contained in the hydrocarbon group having 1 to 36 carbon atoms may be replaced with --O--, --S--, --CO-- or --SO2--. L 10When the hydrocarbon group having 1 to 36 carbon atoms has a substituent, or when -CH2- contained in the hydrocarbon group is replaced with -O-, -S-, -CO- or -SO2-, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the hydrocarbon group. Examples of groups in which -CH2- in a hydrocarbon group is replaced with -O-, -S-, -SO2- or -CO- include hydroxyl group, carboxyl group, thiol group, carbonyl group, sulfonyl group, oxy group, thio group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, alkanediyloxy group, alkanediyloxycarbonyl group, alkanediylcarbonyl group, alkanediylcarbonyloxy group, alkylthio group, alkylsulfonyl group, alkanediylsulfonyl group, alkanediylthio group, cycloalkoxy group, cycloalkylalkoxy group, alkoxycarbonyloxy group, aromatic hydrocarbon group-carbonyloxy group, aromatic hydrocarbon group-carbonyl group, aromatic hydrocarbon group-oxy group, and groups in which two or more of these groups are combined, etc. Examples of these replaced groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. Furthermore, examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the same groups as exemplified in this specification, within the upper limit of the number of carbon atoms permitted.

[0037] L 10 Examples of the substituent that the hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, and the like. L 10 contains a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group such as an alkanediyl group, the chain hydrocarbon group such as an alkanediyl group bonded to the alicyclic hydrocarbon group or aromatic hydrocarbon group (the terminal of the alkanediyl group may be an alkyl group such as a methyl group) can be regarded as substantially a substituent of the alicyclic hydrocarbon group or aromatic hydrocarbon group. 10 L is a group in which -CH2- in the hydrocarbon group is replaced with -O- or -CO-, etc. 10can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, or an alkylcarbonyloxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L 10 The hydrocarbon group having 1 to 36 carbon atoms may have one or more substituents.

[0038] L 10represents a single bond, an alkanediyl group having 1 to 6 carbon atoms (provided that -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), a cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that the cyclic hydrocarbon group may have a substituent and the -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-), or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms with a cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that the cyclic hydrocarbon group has and -CH2- in the alkanediyl group may be replaced with -O- or -CO-, and -CH2- in the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-.) is preferred, and a single bond, an alkanediyl group having 1 to 4 carbon atoms (wherein -CH2- in the alkanediyl group may be replaced with -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- in the alicyclic hydrocarbon group may be replaced with -O -, -S-, -SO2- or -CO-), an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced with -O- or -CO-, and -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-), or an alkanediyl group having 1 to 4 carbon atoms and a substituent. and an aromatic hydrocarbon group having 6 to 18 carbon atoms which may be present (provided that -CH2- contained in the alkanediyl group may be replaced with -O- or -CO-). More preferred is a single bond, an alkanediyl group having 1 to 4 carbon atoms (provided that -CH2- contained in the alkanediyl group may be replaced with -O- or -CO-), or an alicyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O- or -CO-).), a phenylene group which may have a substituent, a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), or a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and a phenylene group which may have a substituent (provided that -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and even more preferably a single bond or an alkanediyl group having 1 to 4 carbon atoms (provided that -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-).

[0039] Examples of the anion (I) include the following anions: TIFF2025026391000034.tif149164

[0040] TIFF2025026391000035.tif186162

[0041] Specific examples of the carboxylate (I) include salts of any combination of the above-mentioned cations and anions. Specific examples of the salt (I) are shown in the table below. In the following table, each symbol represents the symbol attached to the structure representing the above-mentioned anion and cation, and "~" indicates that the carboxylate (I) corresponds to the anion (I). For example, the carboxylate (I-1) is a salt consisting of the anion represented by formula (Ia-1) and the cation represented by formula (Ic-1), the carboxylate (I-2) is a salt consisting of the anion represented by formula (Ia-2) and the cation represented by formula (Ic-1), and the carboxylate (I-41) is a salt consisting of the anion represented by formula (Ia-1) and the cation represented by formula (Ic-2). TIFF2025026391000036.tif6273 [Table 1] TIFF2025026391000038.tif114157

[0042] Among these, the carboxylate (I) is preferably a salt obtained by combining an anion represented by any one of formulas (Ia-1) to (Ia-12), and (Ia-31) to (Ia-40), and a cation represented by any one of formulas (Ic-1) to (Ic-50).

[0043] <Method for producing carboxylate (I)> The carboxylate (I) can be produced by reacting a salt represented by the formula (Ic) with a salt represented by the formula (Ib) in a solvent. TIFF2025026391000039.tif47167 [wherein all symbols have the same meanings as defined above.] Examples of the solvent used in this reaction include chloroform, acetonitrile, and ion-exchanged water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours.

[0044] The salt represented by formula (Ib) can be produced by reacting the compound represented by formula (I-b1) with silver oxide in a solvent. TIFF2025026391000040.tif28166 [wherein all symbols have the same meanings as defined above.] Solvents for this reaction include chloroform, acetonitrile, and the like. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours.

[0045] Examples of the compound represented by formula (I-b1) include compounds represented by the following formulas: These compounds are easily available on the market, or can be easily produced by known methods. TIFF2025026391000041.tif65158

[0046] In the salt (Ic), R 1A But *-OL 11 -CO-OR 10 The salt represented by formula (I-c1) can be produced by reacting a salt represented by formula (Ie) with a compound represented by formula (If) in a solvent in the presence of a base catalyst. TIFF2025026391000042.tif54169 [wherein all symbols have the same meanings as defined above.] The base includes potassium carbonate, potassium iodide, pyridine, triethylamine and the like. Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours.

[0047] Examples of the compound represented by formula (If) include the compounds represented by the following formulas, which are readily available on the market and can also be readily produced by known methods. TIFF2025026391000043.tif13165

[0048] The salt represented by formula (Ie) can be produced by passing the salt represented by formula (I-e') through an ion exchange resin. TIFF2025026391000044.tif50138 [wherein all symbols have the same meanings as defined above.] The ion exchange resin may be, for example, ion exchange resin (No. 6, 100-200 mesh, manufactured by Wako Pure Chemical Industries, Ltd.). The solvent may be methanol or the like.

[0049] When X is a sulfur atom, the salt represented by formula (I-e') can be produced by reacting a compound represented by formula (Ig) with a compound represented by formula (Ih) in the presence of trifluoroacetic anhydride and trifluoromethanesulfonic acid in a solvent, followed by treating with a base. TIFF2025026391000045.tif48161 [wherein all symbols have the same meanings as defined above.] Examples of the solvent include chloroform, monochlorobenzene, and acetonitrile. The reaction temperature is usually 15° C. to 100° C., and the reaction time is usually 0.5 to 24 hours.

[0050] Examples of the compound represented by formula (Ig) include compounds represented by the following formula, and are readily available on the market. TIFF2025026391000046.tif79144

[0051] Examples of the compound represented by formula (Ih) include compounds represented by the following formula, and are readily available on the market. TIFF2025026391000047.tif23144

[0052] The salt represented by formula (Ie) in which X is an iodine atom (salt represented by formula (I-e1)) can be produced by reacting a compound represented by formula (Ii) with a compound represented by formula (Ih) in the presence of potassium peroxymonosulfate and sulfuric acid in a solvent, followed by treatment with hydrochloric acid. TIFF2025026391000048.tif42155 [wherein all symbols have the same meanings as defined above.] Examples of the solvent include chloroform, monochlorobenzene, and acetonitrile. The reaction temperature is usually 15° C. to 100° C., and the reaction time is usually 0.5 to 24 hours.

[0053] Examples of the compound represented by formula (Ii) include compounds represented by the following formula, and are readily available on the market. TIFF2025026391000049.tif15138

[0054] In the salt (Ic), R 1A But *-OR 10The salt represented by formula (I-c2) can be produced by reacting a salt represented by formula (Ie) with a compound represented by formula (I-f1) in a solvent in the presence of a base catalyst. TIFF2025026391000050.tif58161 [wherein all symbols have the same meanings as above. X X represents a hydroxy group or a chlorine atom. Examples of the catalyst include carbonyldiimidazole, potassium carbonate, potassium iodide, pyridine, triethylamine, potassium hydroxide, and sodium hydroxide. Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours. Examples of the compound represented by formula (I-f1) include the compounds represented by the following formulas, which are readily available on the market and can also be readily produced by known methods. TIFF2025026391000051.tif29138

[0055] In the salt (Ic), R 1A But, *-O-CO-OR 10 The salt represented by formula (I-c3) can be produced by reacting a salt represented by formula (Ie) with a compound represented by formula (I-f2) in a solvent in the presence of carbonyldiimidazole. TIFF2025026391000052.tif56163 [wherein all symbols have the same meanings as defined above.] Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours. The compound represented by formula (I-f2) includes corresponding compounds among the compounds represented by formula (I-f1), and is easily available on the market, and can also be easily produced by known production methods.

[0056] In the salt (Ic), R 1A But, *-O-CO-R 10 The salt represented by formula (I-c4) can also be produced by reacting a salt represented by formula (Ie) with a catalyst represented by formula (I-f3) in a solvent. TIFF2025026391000053.tif57162 [wherein all symbols have the same meanings as defined above.] Examples of the catalyst include carbonyldiimidazole, potassium carbonate, potassium iodide, pyridine, triethylamine, potassium hydroxide, and sodium hydroxide. Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours.

[0057] Examples of the compound represented by formula (I-f3) include the compounds represented by the following formulas, and are readily available on the market. TIFF2025026391000054.tif18136

[0058] In the salt (Ic), R 1B But *-OL 11 -CO-OR 10 , *-OR 10 OR*-O-CO-OR 10 and a salt R 1A and R 1B But *-OL 11 -CO-OR 10 , *-OR 10 OR*-O-CO-OR 10 The salts each having the formula R 1A Ga*-OL 11 -CO-OR10 , *-OR 10 OR*-O-CO-OR 10 In the reaction scheme used in the example of the production method of the salt, the salt represented by formula (1-e) can be replaced with a salt represented by the following formula (I-e″) or formula (I-e′″). TIFF2025026391000055.tif50143 [wherein all symbols have the same meanings as defined above.]

[0059] [Structural unit derived from a carboxylate represented by formula (I)] The structural unit derived from the carboxylate represented by formula (I) is a structural unit represented by formula (IP) (hereinafter sometimes referred to as "structural unit (IP)"). TIFF2025026391000056.tif50126 [wherein all symbols have the same meanings as defined above.] The structural unit (IP) is CH2=CR contained in the carboxylate (I). bb1 This shows the state in which the double bond is cleaved. Such a structural unit (IP) functions as a carboxylic acid generator like the carboxylate (I), and also functions as a structural unit constituting a compound or resin.

[0060] [Resin containing structural unit (IP)] The resin of the present invention is a resin containing a structural unit (IP) (hereinafter, may be referred to as "resin (Ap)"). The resin (Ap) may be a homopolymer containing one type of structural unit (IP) or a copolymer containing two or more types of structural units (IP). The resin (Ap) may also contain a structural unit other than the structural unit (IP). As the structural unit other than the structural unit (IP), as described below, there may be mentioned a structural unit having an acid labile group (hereinafter, sometimes referred to as "structural unit (a1)") and a structural unit other than the structural unit (a1). As the structural unit other than the structural unit (a1), there may be mentioned a structural unit not having an acid labile group (hereinafter, sometimes referred to as "structural unit (s)") and a structural unit known in the art. Here, the "acid labile group" means a group having a leaving group, which is released by contact with an acid, and the structural unit is converted into a structural unit having a hydrophilic group (e.g., a hydroxyl group or a carboxyl group). The content of the structural unit (IP) is 0.1 mol% or more, preferably 0.5 mol% or more, more preferably 0.8 mol% or more, and even more preferably 1 mol% or more, based on the total structural units of the resin (Ap). Also, it is 100 mol% or less, preferably 50 mol% or less, more preferably 30 mol% or less, and even more preferably 10 mol% or less. Specifically, it is 0.1 to 100 mol%, preferably 0.5 to 50 mol%, more preferably 0.8 to 30 mol%, and even more preferably 1 to 10 mol%. In particular, when the resin (Ap) is used in a resist composition, as described below, it is preferable that the resin (Ap) further contains the structural unit (a1) in addition to the structural unit (IP). Furthermore, as described below, when the resin (Ap) is used in a resist composition, regardless of whether it contains the structural unit (a1), it may be used in combination with a resin containing the structural unit (a1) (hereinafter sometimes referred to as "resin (A)"). Hereinafter, the resin (Ap) and / or the resin (A) may be referred to as "resin (A), etc." The resin (Ap) and the resin (A) preferably further contain a structural unit other than the structural unit (a1).

[0061] <Structural unit (a1)> The structural unit (a1) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid labile group contained in the resin (A) etc. is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF2025026391000057.tif1988[In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, or R a1 and R a2 are bonded to each other to form, together with the carbon atom to which they are bonded, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * denotes a binding site.] TIFF2025026391000058.tif2171[In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’ are bonded to each other to form, together with the carbon atom to which they are bonded and X, a heterocyclic group having 3 to 20 carbon atoms, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X represents an oxygen atom or a sulfur atom. na′ represents 0 or 1. * denotes a binding site.]

[0062] R a1 , R a2 and R a3 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. Ra1 , R a2 and R a3 Examples of the alkenyl group in include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, and a nonenyl group. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site). R a1 , R a2 and R a3 The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms. TIFF2025026391000059.tif10150R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group in include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and an alicyclic hydrocarbon group are combined (for example, an alkylcycloalkyl group or a cycloalkylalkyl group such as a methylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, or a norbornylethyl group), an aralkyl group such as a benzyl group, an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, or the like), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, or the like), and an aryl-cycloalkyl group such as a phenylcyclohexyl group. Preferably, ma is 0 and na is 1. R a1 and R a2 When they are bonded to each other to form an alicyclic hydrocarbon group, -C(R a1 )(R a2 )(R a3 ) includes the following groups. The alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-. TIFF2025026391000060.tif30138

[0063] R a1’ , R a2’ and R a3’ Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups are R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a2’ and R a3’ When they are bonded to each other to form a heterocyclic group together with the carbon atom to which they are bonded and X, -C(R a1’ )(R a2’ )-XR a3’ Examples of the group include the following: * represents a binding site. TIFF2025026391000061.tif18130R a1 , R a2 , R a3 , R a1 , R a2’ and R a3’ The halogen atom which may be contained includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a1’ and R a2’ At least one of these is preferably a hydrogen atom. na' is preferably 0.

[0064] Examples of the group (1) include the following groups. In formula (1), R a1 , R a2 and R a3 is an alkyl group, ma = 0, and na = 1. As the group, a tert-butoxycarbonyl group is preferable. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, R a3 is an alkyl group, ma=0, and na=1. In formula (1), R a1 and R a2 are each independently an alkyl group; R a3 is an adamantyl group, ma=0, and na=1. Specific examples of the group (1) include the following groups: * represents a binding site. TIFF2025026391000062.tif150162

[0065] Specific examples of the group (2) include the following groups: * represents a bonding site. TIFF2025026391000063.tif55153

[0066] The monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid labile group. Of the (meth)acrylic monomers having an acid labile group, preferred are those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms. By using a resin (A) or the like having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group in a resist composition, the resolution of the resist pattern can be improved.

[0067] Examples of the structural unit derived from the (meth)acrylic monomer having the group (1) include a structural unit represented by formula (a1-0) (hereinafter, sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter, sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter, sometimes referred to as structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1) and the structural unit (a1-2), more preferably at least one structural unit selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2025026391000064.tif43144 [In formula (a1-0), formula (a1-1) and formula (a1-2), all symbols have the same meaning as defined above.]

[0068] R a01 , R a4 , R a5 The halogen atom in the formula (I) includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a01 , R a4 , R a5 Examples of the alkyl group which may have a halogen atom in the above formula include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. The alkyl group is preferably a methyl group or an ethyl group, and more preferably a methyl group. R a01 , Ra4 and R a5 is preferably a hydrogen atom or a methyl group, and more preferably a methyl group. L a01 , L a1 and L a2 is preferably an oxygen atom or *-O-(CH2) k01 It is -CO-O- (wherein k01 is preferably an integer of any one of 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 and R a04 The alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group and combinations thereof in the formula (1) are R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a6 and R a7 The alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and combinations thereof in the formula (1) include R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a02 , R a03 , and R a04 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a6 and R a7 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group, or a t-butyl group, and even more preferably an ethyl group, an isopropyl group, or a t-butyl group. R a6 and R a7 The alkenyl group in is preferably an alkenyl group having 2 to 6 carbon atoms, and more preferably an ethenyl group, a propenyl group, an isopropenyl group, or a butenyl group. R a02 , R a03 , R a04 , Ra6 and R a7 The alicyclic hydrocarbon group preferably has 5 to 12 carbon atoms, and more preferably 5 to 10 carbon atoms. R a02 , R a03 , R a04 , R a6 and R a7 The aromatic hydrocarbon group preferably has 6 to 12 carbon atoms, and more preferably 6 to 10 carbon atoms. In the group in which an alkyl group and an alicyclic hydrocarbon group are combined, the total number of carbon atoms in the combination of the alkyl group and the alicyclic hydrocarbon group is preferably 18 or less. In the group in which an alkyl group and an aromatic hydrocarbon group are combined, the total number of carbon atoms in the combination of the alkyl group and the aromatic hydrocarbon group is preferably 18 or less. R a02 and R a03 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group which may have a halogen atom. R a04 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group which may have a halogen atom. R a6 and R a7 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkenyl group having 2 to 6 carbon atoms which may have a halogen atom, or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, more preferably a methyl group, ethyl group, isopropyl group, t-butyl group, ethenyl group, phenyl group or naphthyl group which may have a halogen atom, and even more preferably an ethyl group, isopropyl group, t-butyl group, ethenyl group or phenyl group which may have a halogen atom. m1' is preferably an integer of 0 to 3, and more preferably 0 or 1. n1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1' is preferably 0 or 1.

[0069] Examples of the structural unit (a1-0) include a structural unit represented by any one of formulas (a1-0-1) to (a1-0-24) and R a01 and structural units in which the methyl group corresponding to the formula (a1-0-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group (an alkyl group having a halogen atom) or another alkyl group. Structural units represented by any of formulas (a1-0-1) to (a1-0-10), (a1-0-13), (a1-0-14) and (a1-0-19) to (a1-0-24) are preferred. TIFF2025026391000065.tif119160

[0070] Examples of the structural unit (a1-1) include structural units derived from monomers described in JP 2010-204646 A. Among them, structural units represented by any one of formulas (a1-1-1) to (a1-1-7) and R in the structural unit (a1-1) are a4 In the above formula (a1-1-1), a methyl group is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. In the above formula (a1-1-2), a methyl group is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. In the above formula (a1-1-3), a methyl group is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. In the above formula (a1-1-4), a structural unit is more preferred. TIFF2025026391000066.tif38168

[0071] The structural unit (a1-2) includes a structural unit represented by any one of formulas (a1-2-1) to (a1-2-20) and R a5 and structural units in which a methyl group corresponding to the formula (a1-2-2), (a1-2-5), (a1-2-6), and (a1-2-10) to (a1-2-20) are replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. TIFF2025026391000067.tif91163

[0072] When the resin (A) etc. contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these units is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A) etc. Also, 95 mol% or less is mentioned, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, 10 to 95 mol% is mentioned, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, even more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin (A) or the like contains the structural unit (a1-0), the content thereof is 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, even more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, and even more preferably 35 mol% or more, based on the total structural units of the resin (A) or the like. Also, the content is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less, and even more preferably 60 mol% or less. Specifically, the content is 5 to 80 mol%, preferably 5 to 75 mol%, and more preferably 10 to 70 mol%. When the resin (A) etc. contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these units is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A) etc. Also, 95 mol% or less is included, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, 10 to 90 mol% is included, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, even more preferably 20 to 80 mol%, even more preferably 20 to 75 mol%, and even more preferably 20 to 70 mol%.

[0073] An example of the structural unit (a1) having a group (2) is a structural unit represented by formula (a1-4) (hereinafter, sometimes referred to as "structural unit (a1-4)"). TIFF2025026391000068.tif31118 [In formula (a1-4), all symbols have the same meaning as defined above.]

[0074] R a1 and R a17 Examples of the halogen atom in include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. R a1 and R a17Examples of the alkyl group having 1 to 6 carbon atoms, which may have a halogen atom, include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. R a1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and further preferably a hydrogen atom or a methyl group. R a17 Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 4, and more preferably 1 to 3. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a17 Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a17Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group. R a17 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a17 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a17 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0075] A a11Examples of the alkanediyl group include straight-chain alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl groups. Examples of branched alkanediyl groups include branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, and undecane-1,10-diyl group. The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, still more preferably 1 to 3, and even more preferably 1 or 2. In addition, A a11 is also preferably a methylene group or an ethylene group. R a18 Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group. A a11 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a18 When it is replaced with -, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the alkanediyl group. A a11 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a18 Groups substituted with - include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), a carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), an oxy group (a group in which -CH2- in a methylene group is replaced with -O-), an amino group (a group in which -CH2- in a methyl group is replaced with -NR a18-), alkoxy group (a group in which -CH2- at any position in the alkyl group is replaced with -O-), alkoxycarbonyl group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -O-CO-), alkylcarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -CO-), alkylamino group (a group in which -CH2- at any position in the alkyl group is replaced with -NR a18 -), peptide group (the -CH2-CH2- in the ethylene group is replaced by -CO-NR a18 -), alkanediyloxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -O-), alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -CO-), alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -CO-O-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -SO2-), an alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -S-), an alkanediylamino group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -NR a18 These substituted groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. The alkylamino group includes alkylamino groups having 1 to 11 carbon atoms, such as a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, an octylamino group, etc. The number of carbon atoms in the alkylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. The alkanediylamino group includes an alkanediylamino group having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, etc. The number of carbon atoms in the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. For example, A a11 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a18 Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, *-CO-OA a12 -CO-O-, *-O-CO-A a12 -O-, *-OA a12 -CO-O-, *-CO-OA a12 -O-CO-, *-O-CO-A a12 -O-CO-, *-CO-NR a18 Among them, *-CO-O- and *-CO-OA a12 -CO-O-, *-OA a12 -CO-O-, *-CO-NR a18 - is preferred, where A a12 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents R a1 A represents the bonding site with the carbon atom to which it is attached. a12 The alkanediyl group of A is as follows, within the upper limit of the carbon number. a11 Examples of the alkanediyl groups include those shown above. A a11 is a single bond, *-CO-O- or *-CO-OA a12 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. na1 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na11 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and further preferably 0 or 1. mc is preferably 0 or 1. R a34 , Ra35 and R a36 Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group consisting of a combination thereof. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site): TIFF2025026391000069.tif10151 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined (e.g., alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, and norbornylethyl group), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), and aryl-cycloalkyl groups such as phenylcyclohexyl group. In particular, R a36 Examples of the alkyl group include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these groups. R a35 and R a36Examples of the divalent hydrocarbon group having 2 to 20 carbon atoms that is formed by bonding together with the -CO- to which they are bonded include the following groups. * represents a bonding site, and one of the groups is R a34 This is the binding site for TIFF2025026391000070.tif15105R a34 is preferably a hydrogen atom. R a35 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a methyl group or an ethyl group. R a36 The hydrocarbon group in R is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. a36 The alkyl group and the alicyclic hydrocarbon group in R are preferably unsubstituted. a36 The aromatic hydrocarbon group in is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0076] -OC(R a34 )(R a35 )-OR a36 is eliminated on contact with an acid (e.g., p-toluenesulfonic acid) to form a hydroxy group or a carboxy group, respectively. -X a1 -OC(R a34 )(R a35 )-OR a36 In the case of a benzene ring, A a11 It is preferable that at least one of them is bonded to the o-position or the m-position, and more preferable that it is bonded to the p-position. In the case of a naphthalene ring, A a11 When the bonding position of A is the 1st position, it may be bonded to any of the 2nd to 8th positions. a11When the bonding position of A is the 2-position, it may be bonded to any of the 1-position and the 3-8-positions. a11 When the bonding position of A is the 1st position, at least one of them is preferably bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. a11 When the bonding position is the 2-position, it is preferably bonded to the 4- to 7-positions, and more preferably bonded to the 5- or 6-position. Examples of the structural unit (a1-4) include structural units derived from monomers described in JP 2010-204646 A. Preferably, the structural units represented by formulas (a1-4-1) to (a1-4-42) and R in the structural unit (a1-4) are a1 and more preferably, the structural units represented by formulae (a1-4-1) to (a1-4-5), (a1-4-10), (a1-4-13), (a1-4-14), (a1-4-19), and (a1-4-20), respectively. TIFF2025026391000071.tif227163 When the resin (A) or the like contains the structural unit (a1-4), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total of all structural units of the resin (A) or the like. Also, 95 mol% or less is mentioned, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, even more preferably 20 to 85 mol%, even more preferably 20 to 70 mol%, and even more preferably 20 to 65 mol%.

[0077] An example of a structural unit derived from a (meth)acrylic monomer having the group (2) is a structural unit represented by formula (a1-5) (hereinafter, may be referred to as "structural unit (a1-5)"). TIFF2025026391000072.tif4558 [In formula (a1-5), all symbols have the same meaning as defined above.]

[0078] R a8 Examples of the halogen atom in include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Of these, a fluorine atom is preferred. R a8 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, and a perfluorohexyl group. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group, or a trifluoromethyl group. L 51 is preferably an oxygen atom. L 52 and L 53 Of these, it is preferred that one is -O- and the other is -S-. It is preferable that s1 is 1. s1' is preferably an integer of 0 to 2. Z a1 is preferably a single bond or -CH2-CO-O-.

[0079] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP 2010-61117 A. Among them, the structural units represented by formulae (a1-5-1) to (a1-5-4) are preferred, and the structural unit represented by formula (a1-5-1) or (a1-5-2) is more preferred. TIFF2025026391000073.tif33133

[0080] When the resin (A) or the like contains the structural unit (a1-5), the content thereof is 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, even more preferably 10 mol% or more, even more preferably 20 mol% or more, and even more preferably 25 mol% or more, based on the total structural units of the resin (A) or the like. Also, the content is 80 mol% or less, preferably 70 mol% or less, more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 45 mol% or less, even more preferably 40 mol% or less, and even more preferably 30 mol% or less. Specifically, the content is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, even more preferably 5 to 40 mol%, and even more preferably 5 to 30 mol%.

[0081] An example of the structural unit (a1) having a group (1) is a structural unit represented by formula (a1-6) (hereinafter, sometimes referred to as "structural unit (a1-6)"). TIFF2025026391000074.tif3581 [In formula (a1-6), all symbols have the same meaning as defined above.]

[0082] R a61 Examples of the halogen atom in include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Of these, a fluorine atom is preferred. R a61Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, and a perfluorohexyl group. R a61 is preferably a hydrogen atom, a methyl group, or a trifluoromethyl group. R a62 , R a63 and R a64 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and further preferably a methyl group or an ethyl group. R a62 , R a63 and R a64 The cyclic hydrocarbon group in the formula (I) includes an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, and a norbornyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, and more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group and a naphthylene group. Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. R a62 and R a63 Examples of the ring formed by bonding with each other include an adamantane ring, a cyclopentane ring, and a cyclohexane ring. a62 and R a63 When they are bonded to each other to form a ring, -C(R a62 )(R a63 )(R a64 ) includes the following groups. * represents a bonding site with an oxygen atom. The ring preferably has 3 to 16 carbon atoms, more preferably 3 to 12 carbon atoms. TIFF2025026391000075.tif33110

[0083] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. L a61 and L a62 is preferably each independently a methylene group or an ethylene group. X a61 is preferably a single bond or -CO-O-*, and more preferably a single bond. X a62 is preferably a single bond or *-OL a61 -, and more preferably a single bond. Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms for Ar include a phenylene group, a 1-naphthylene group, a 2-naphthylene group, a 1-anthrylene group, a 9-anthrylene group, a biphenylene group, a 1-phenanthrylene group, and a 2-phenanthrylene group. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. Examples of the halogen atom include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and further preferably a methyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and further preferably a methoxy group. Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and further preferably a methoxymethyl group. Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, a butyryl group, etc. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. The substituent is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. Ar is preferably a phenylene group which may have a substituent, and more preferably a phenylene group which may have a hydroxy group.

[0084] Examples of the structural unit (a1-6) include structural units represented by formulae (a1-6-1) to (a1-6-44), preferably structural units represented by formulae (a1-6-1) to (a1-6-9), more preferably structural units represented by formulae (a1-6-1), (a1-6-2), (a1-6-4), (a1-6-5), (a1-6-7) or (a1-6-8), and even more preferably structural units represented by formulae (a1-6-1) or (a1-6-2). a61The structural unit in which the hydrogen atom corresponding to is replaced by a methyl group, etc., and the structural unit in which R a61 The structural unit (a1-6) also includes a structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom. TIFF2025026391000076.tif226161

[0085] When the resin (A) or the like contains the structural unit (a1-6), the content thereof is 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, even more preferably 10 mol% or more, even more preferably 20 mol% or more, even more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on the total structural units of the resin (A) or the like. Also, the content is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, the content is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 65 mol%.

[0086] Further, examples of the structural unit (a1) include the following structural units. TIFF2025026391000077.tif33167

[0087] When the resin (A) etc. contains the structural units represented by the formulas (a1-3-1) to (a1-3-7), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A) etc. Also, the content is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 10 to 95 mol% is preferred, 15 to 90 mol% is more preferred, 20 to 85 mol% is even more preferred, 20 to 70 mol% is even more preferred, and 20 to 60 mol% is particularly preferred.

[0088] Further, examples of the structural unit (a1) include the following structural units. TIFF2025026391000078.tif51105 When the resin (A) etc. contains structural units represented by formulas (a1-7-1) to (a1-7-3), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A) etc. Also, 95 mol% or less is mentioned, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, it is preferably 10 to 60 mol %, more preferably 15 to 55 mol %, even more preferably 20 to 50 mol %, even more preferably 20 to 45 mol %, and particularly preferably 20 to 40 mol %.

[0089] Structural unit(s) The structural unit (s) is derived from a monomer having no acid labile group (hereinafter, may be referred to as "monomer (s)"). As the monomer from which the structural unit (s) is derived, a monomer having no acid labile group known in the resist field can be used. The structural unit (s) preferably has a hydroxy group, a carboxy group, or a lactone ring. If a resin containing a structural unit having a hydroxy group or a carboxy group and no acid labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and no acid labile group (hereinafter sometimes referred to as "structural unit (a3)") is used in the resist composition of the present invention, the resolution of the resist pattern and adhesion to the substrate can be improved. In addition to the above-mentioned structural units, the structural unit (s) may also include a structural unit having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"), a structural unit having a sultone structure (hereinafter sometimes referred to as "structural unit (a6)"), or a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)").

[0090] <Structural unit (a2)> The structural unit (a2) is a structural unit represented by formula (a2) and has an alcoholic hydroxy group, a phenolic hydroxy group, a carboxy group, or the like. TIFF2025026391000079.tif4194[In formula (a2), R a2 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group is -O-, -CO- or -NR a28 - may be replaced. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. L a21represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms, the hydrocarbon group optionally having a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. L a22 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms which may have a fluorine atom, and -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-. na2 represents an integer of 1 to 5, and when na2 is 2 or more, a plurality of L a22 may be the same or different.

[0091] R a2 Examples of the halogen atom in include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. R a2 Examples of the alkyl group having 1 to 6 carbon atoms, which may have a halogen atom, include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. R a2 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and further preferably a hydrogen atom or a methyl group. A a21Examples of the alkanediyl group include straight-chain alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl groups. Examples of branched alkanediyl groups include branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, and undecane-1,10-diyl group. The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, still more preferably 1 to 3, and still more preferably 1 or 2. In addition, Aa21 is also preferably a methylene group or an ethylene group. R a28 Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group. A a21 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 When it is replaced with -, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the alkanediyl group. A a21 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 As described above, examples of the group substituted for - include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an amino group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylamino group, a peptide group, an alkanediylamino group, etc. These substituted groups include the same as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. The alkylamino group includes alkylamino groups having 1 to 11 carbon atoms, such as a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, an octylamino group, etc. The number of carbon atoms in the alkylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. The alkanediylamino group includes an alkanediylamino group having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, etc. The number of carbon atoms in the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3. Among them, A a21 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, *-CO-OA a22 -CO-O-, *-O-CO-A a22 -O-, *-OA a22 -CO-O-, *-CO-OA a22 -O-CO-, *-O-CO-A a22 -O-CO-, *-CO-NR a28 Among them, *-CO-O- and *-CO-OA a22 -CO-O-, *-OA a22 -CO-O-, *-CO-NR a28 - is preferred, where A a22 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents R a2 A represents the bonding site with the carbon atom to which it is attached. a22 The alkanediyl group of A is as follows, within the upper limit of the carbon number. a21 Examples of the alkanediyl groups include those shown above. A a21 is a single bond, *-CO-O- or *-CO-OA a22-CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. L a21 The hydrocarbon group in is a (na2+1)-valent hydrocarbon group, and examples of such cyclic hydrocarbon groups include linear or branched chain hydrocarbon groups, monocyclic or polycyclic (including spiro rings, fused rings or bridged rings) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may be groups formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group). L a21 Examples of the chain hydrocarbon group include divalent to hexavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, an alkanepentyl group, and an alkanehexyl group. Examples of the alkanediyl group include A a21 Examples of the alkanediyl groups include those shown above. Examples of the alkanetriyl group include a methanetriyl group, an ethanetriyl group, a propanetriyl group, a butanetriyl group, a pentanetriyl group, a hexanetriyl group, a heptanetriyl group, an octanetriyl group, a nonanetriyl group, a decanetriyl group, an undecanetriyl group, a dodecanetriyl group, a tridecanetriyl group, a tetradecanetriyl group, a pentadecanetriyl group, a hexadecanetriyl group, and a heptadecanetriyl group. Examples of the alkanetetrayl group include a methanetetrayl group, an ethanetetrayl group, a propanetetrayl group, a butanetetrayl group, a pentanetetrayl group, a hexanetetrayl group, a heptanetetrayl group, an octanetetrayl group, a nonanetetrayl group, a decanetetrayl group, an undecanetetrayl group, a dodecanetetrayl group, a tridecanetetrayl group, a tetradecanetetrayl group, a pentadecanetetrayl group, a hexadecanetetrayl group, and a heptadecanetetrayl group. Examples of the alkanol groups include a methane pentaylene group, an ethane pentaylene group, a propane pentaylene group, a butane pentaylene group, a pentane pentaylene group, and a hexane pentaylene group. Examples of the alkanehexyl group include a methanehexyl group, an ethanehexyl group, a propanehexyl group, a butanehexyl group, a pentanehexyl group, and a hexanehexyl group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 10, still more preferably 1 to 9, even more preferably 1 to 8, even more preferably 1 to 6, even more preferably 1 to 5, and particularly preferably 1 to 4. L a21 Examples of the monocyclic and polycyclic alicyclic hydrocarbon groups in the formula (I) include the following alicyclic hydrocarbon groups: The binding site may be any position. TIFF2025026391000080.tif45168For example, divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkanepentyl group, and a cycloalkanehexyl group are exemplified. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclodecanetriyl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, and cyclodecanetetrayl group; Examples of polycyclic alicyclic hydrocarbon groups include norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, decahydronaphthalenediyl group, bicyclo[3.3.0]octanediyl group, norbornanetriyl group, adamantanetriyl group, decahydronaphthalenetriyl group, bicyclo[3.3.0]octanetriyl group, norbornanetetrayl group, adamantanetetrayl group, decahydronaphthalenetetrayl group, and bicyclo[3.3.0]octanetetrayl group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 18 carbon atoms, further preferably 3 to 16 carbon atoms, and further preferably 3 to 12 carbon atoms. L a21 Examples of the aromatic hydrocarbon group in include divalent to hexavalent aromatic hydrocarbon groups such as an arylene group, an arenetriyl group, an arenettetrayl group, an arenetyl group, and an arenethexyl group. Specific examples of aromatic hydrocarbon groups include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, a benzenetriyl group, a naphthalenetriyl group, an anthracenetriyl group, a biphenylenetriyl group, a phenanthrenetriyl group, a benzenetetrayl group, a naphthalenetetrayl group, an anthracenetetrayl group, a biphenylenetetrayl group, and a phenanthrenetetrayl group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The aromatic hydrocarbon group preferably has 6 to 20 carbon atoms, more preferably 6 to 18 carbon atoms, further preferably 6 to 14 carbon atoms, and further preferably 6 to 10 carbon atoms. Examples of groups that combine two or more of these groups include a group that combines an alicyclic hydrocarbon group with a chain hydrocarbon group, a group that combines an aromatic hydrocarbon group with a chain hydrocarbon group, a group that combines an alicyclic hydrocarbon group with an aromatic hydrocarbon group, and a group that combines an alicyclic hydrocarbon group with a chain hydrocarbon group and an aromatic hydrocarbon group. In the combination, two or more of each of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may be combined. In addition, when any of the groups is A a21 and L a22 may be bound to Examples of groups in which -CH2- in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkylthio group (a group in which -CH2- at any position in an alkyl group is replaced by -S-), and a group in which -CH2-CH2- at any position in the alkyl group is replaced with -O-CO-), an alkoxycarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -O-CO-), an alkylsulfonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -SO2-), an alkylcarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -CO-O-), an oxy group (a group in which -CH2- in a methylene group is replaced with -O- a carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), a thio group (a group in which -CH2- in a methylene group is replaced with -S-), a sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), an alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced with -O-), an alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position in an alkanediyl group is replaced with -O-CO-), an alkanediylcarbonyl group (a an alkanediyl group in which -CH2- at any position is replaced with -CO-), an alkanediylcarbonyloxy group (an alkanediyl group in which -CH2-CH2- at any position is replaced with -CO-O-), an alkanediylsulfonyl group (an alkanediyl group in which -CH2- at any position is replaced with -SO2-), an alkanediylthio group (an alkanediyl group in which -CH2- at any position is replaced with -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group,Examples of such groups include an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group that combines two or more of these groups. Examples also include groups in which one or more hydrogen atoms of these groups are replaced with a bonding site. Examples of such replaced groups include the same groups as those exemplified in this specification. Furthermore, examples of groups in which --CH.sub.2-- contained in an alicyclic hydrocarbon group is replaced by --O--, --S--, --CO-- or --SO.sub.2-- include the same as those exemplified in this specification. Examples of the combined groups in which --CH2-- is replaced by --O--, --S--, --CO-- or --SO2-- include the following groups: The bonding site may be any position. TIFF2025026391000081.tif27164L a21 The hydrocarbon group in may have one or more substituents, such as a halogen atom, a haloalkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 16 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), an acryloyloxy group, or a methacryloyloxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a21 The hydrocarbon group in the formula (I) can have a halogen atom as a substituent, and thus can have a substituent such as a haloalkyl group. Examples of the haloalkyl group include a fluorinated alkyl group, a chlorinated alkyl group, a brominated alkyl group, and an iodinated alkyl group, and examples thereof include a chloromethyl group, a bromomethyl group, an iodomethyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, and a perfluorobutyl group. The number of carbon atoms in the haloalkyl group is preferably 1 to 8, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. L a21 The hydrocarbon group of L a21can substantially have a substituent such as an alkyl group. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 10, still more preferably 1 to 8, still more preferably 1 to 6, still more preferably 1 to 4, and still more preferably 1 to 3. L a21 L is a group in which -CH2- in the hydrocarbon group is replaced with -O- or -CO-, etc. a21 can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, a thiol group, a sulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an acryloyloxy group, or a methacryloyloxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 12, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The number of carbon atoms in the alkoxycarbonyl group, the alkylcarbonyl group, or the alkylcarbonyloxy group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 to 3. The number of carbon atoms in the alkoxyalkyl group or the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 8, even more preferably 2 to 6, and even more preferably 2 to 4. The above groups also include the same groups as those exemplified in this specification. L a21The substituents which the hydrocarbon group in the formula (I) may have are preferably a halogen atom, a haloalkyl group having 1 to 8 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), more preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 10 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), still more preferably a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, a hydroxy group, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, still more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and still more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, or an ethoxyethoxy group. Also, L a21 In the case where the alkanediyl group is replaced by -O- or -CO-, for example, *-L a23 -X a21 -(L a23 represents an alkanediyl group having 1 to 8 carbon atoms; X a21 represents -O-, -O-CO-, -CO-O-, or -O-CO-O-, and * represents A a21 It is also preferred that the bond is L a21is preferably a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (however, -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (however, -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), or a group formed by combining a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent and a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (however, -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO- and -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-). and more preferably an optionally substituted chain hydrocarbon group having 1 to 10 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), or a group formed by combining an optionally substituted chain hydrocarbon group having 1 to 6 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO- and -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-).

[0092] L a22Examples of the chain hydrocarbon group having 1 to 12 carbon atoms include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, and dodecane-1,12-diyl group. Examples of branched alkanediyl groups include ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, 1-methylpropane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, 1-dimethylpropane-1,3-diyl, pentane-2,4-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, and even more preferably 1 to 4. Examples of the chain hydrocarbon group in which --CH.sub.2-- is replaced by --O-- or --CO-- include the same as those exemplified in this specification. L a22 may have one fluorine atom or two or more fluorine atoms. na2 is preferably an integer of 1 to 4, and more preferably an integer of 1 to 3. L a21 In the case where R is a single bond or a chain hydrocarbon group, examples of the structural unit (a2) include the following structural units. a2 In the same manner as the following structural unit, a structural unit in which a methyl group corresponding to the following formula is replaced with a hydrogen atom or the like is also a suitable structural unit of the structural unit (a2). TIFF2025026391000082.tif69169

[0093] When a resist pattern is produced from the resist composition of the present invention, in the case where a high energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) is used as an exposure light source, the structural unit (a2) having a phenolic hydroxyl group is preferred, and the structural unit (a2-A) described below is more preferred. In addition, in the case where an ArF excimer laser (193 nm) or the like is used, the structural unit (a2) having an alcoholic hydroxyl group is preferred, and the structural unit (a2-C) described below is more preferred. The structural unit (a2) may contain one type alone or two or more types.

[0094] In the structural unit (a2), L a21 In the case where is a cyclic hydrocarbon group, an example of the structural unit having a phenolic hydroxy group or a carboxy group is a structural unit represented by formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF2025026391000083.tif31128 [In formula (a2-A), all symbols have the same meaning as defined above.]

[0095] R a2 and A a21 The groups include the same groups as those exemplified in formula (a2). R a27 Examples of the halogen atom include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom. R a27Examples of the alkyl group having 1 to 6 carbon atoms, which may have a halogen atom, include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, more preferably 1 to 3, further preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a27 Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 4, and more preferably 1 to 3. The alkoxy group is preferably a methoxy group or an ethoxy group, and more preferably a methoxy group. R a27 Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a27Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group. R a27 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a27 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a27 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nA2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na21 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and further preferably 0 or 1. mc is preferably 0 or 1. -X a2 -OH is a benzene ring, Aa21 It is preferable that at least one of them is bonded to the m-position or p-position, and more preferable that it is bonded to the m-position. In the case of a naphthalene ring, A a21 When the bonding position of A is the 1st position, it may be bonded to any of the 2nd to 8th positions. a21 When the bonding position of A is the 2-position, it may be bonded to any of the 1-position and the 3-8-positions. a21 When the bonding position of A is the 1st position, at least one of them is preferably bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. a21 When the bonding position is the 2-position, it is preferably bonded to the 4- to 7-positions, and more preferably bonded to the 5- or 6-position.

[0096] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A-2010-204634 and JP-A-2012-12577. The structural unit (a2-A) includes structural units represented by formulae (a2-2-1) to (a2-2-32) and (a2-3-1) to (a2-3-24), and in these structural units, R in the structural unit (a2-A) a2 and the like, in which the methyl group corresponding to the following formula (I) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. TIFF2025026391000084.tif188169 When the structural unit (a2-A) is contained in the resin (A) or the like, the content of the structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and even more preferably 20 mol% or more, based on the total structural units. Also, it is preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less, even more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 45 mol% or less, and even more preferably 40 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, even more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%. The structural unit (a2-A) may be a compound from which the structural unit (a2-A) is derived (e.g., -CH2-C(-R a2 )- is the double bond CH2=C(-R a2 ) can be polymerized to incorporate the structural unit (a2-A') etc. into the resin (A). For example, structural unit (a1-4) can be polymerized, followed by treatment with an acid such as p-toluenesulfonic acid, to incorporate the structural unit (a2-A) into the resin (A). For example, acetoxystyrene can be polymerized, followed by treatment with an alkali such as tetramethylammonium hydroxide to incorporate the structural unit (a2-A) into the resin (A).

[0097] In the structural unit (a2), L a21 is a cyclic hydrocarbon group, examples of the structural unit having an alcoholic hydroxy group or a carboxy group include a structural unit represented by formula (a2-B) (hereinafter may be referred to as "structural unit (a2-B)"), a structural unit represented by formula (a2-C) (hereinafter may be referred to as "structural unit (a2-C)"), and a structural unit represented by formula (a2-D) (hereinafter may be referred to as "structural unit (a2-D)"). TIFF2025026391000085.tif46102 [In formula (a2-B) and formula (a2-C), R a2 has the same meaning as formula (a2). R a27 has the same meaning as formula (a2-A). L a25 is -O- or *-O-(CH2) k2 represents -CO-O-, k2 represents an integer of any one of 1 to 7. * represents a bonding site with -CO-. X a2 represents a single bond or -CO-. R a25 and R a26 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. nB2 represents an integer of 1 to 5. When nB2 is 2 or more, a plurality of X a2 may be the same or different from each other. nB22 represents an integer of 0 to 8. When nB22 is 2 or more, a plurality of R a27 may be the same or different from each other. nC22 represents an integer of 0 to 10. When nC22 is 2 or more, multiple R a27 may be the same or different. L a25 is preferably -O-, -O-(CH2) f1 It is -CO-O- (wherein f1 represents an integer of 1 to 4), and more preferably -O-. R a2 is preferably a methyl group. X a2 is preferably a single bond. R a25 is preferably a hydrogen atom. R a26 is preferably a hydrogen atom or a hydroxy group. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nB2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. nB22 is preferably an integer of 0 to 3, more preferably 0, 1 or 2, and further preferably 0 or 1. nC22 is preferably an integer of 0 to 6, more preferably an integer of 0 to 3, and further preferably 0 or 1.

[0098] Examples of the structural unit (a2-B) and the structural unit (a2-C) include structural units derived from monomers described in JP-A-2010-204646, the following structural units, and R a2 In particular, structural units represented by any one of formulae (a2-B-1) to (a2-B-5) and formulae (a2-C-1) to (a2-C-9) are preferred. TIFF2025026391000086.tif80164 When the resin (A) or the like contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on the total structural units of the resin (A) or the like. Also, 45 mol% or less is mentioned, preferably 40 mol% or less, more preferably 35 mol% or less, even more preferably 20 mol% or less, and even more preferably 10 mol% or less. Specifically, 1 to 45 mol% is mentioned, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol%, and even more preferably 1 to 10 mol%.

[0099] TIFF2025026391000087.tif51105[In formula (a2-D), R a2 and A a21 have the same meaning as in formula (a2). R a27 has the same meaning as formula (a2-A). R a21 and R a22 each independently represents a fluorinated alkyl group having 1 to 4 carbon atoms. L a24 represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents an integer of 1 to 5. When nD2 is 2 or more, the groups in the multiple parentheses may be the same or different. nD22 represents an integer of 0 to 4. When nD22 is 2 or more, a plurality of R a27 may be the same or different from each other. However, 1≦nD2+nD22≦5. R a21 and R a22 Examples of the fluorinated alkyl groups are each independently a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoropropyl group, a 4,4,4-trifluorobutyl group, and the like. R a21 and R a22 As the alkyl group, a trifluoromethyl group is preferable. L a24 Examples of the alkanediyl group include a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group. L a24 is preferably a single bond or a methylene group. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nD2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, even more preferably 1 or 2, and even more preferably 1. Also preferably, nD2 is 1 and the group in parentheses is bonded to the para position. nD22 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, further preferably 0 or 1, and even more preferably 0.

[0100] The structural unit (a2-D) is more preferably a structural unit represented by the following formula (a2-D1) (hereinafter, sometimes referred to as "structural unit (a2-D1)"). TIFF2025026391000088.tif51108[In formula (a2-D1), R a2 , A a21 , R a27 , nD2 and nD22 each have the same meaning as in formula (a2-D). In formula (a2-D1), R a2 is preferably a hydrogen atom or a methyl group. A a21 is preferably a single bond.

[0101] Examples of the structural unit (a2-D) include the structural units shown below. TIFF2025026391000089.tif62168

[0102] In the structural units represented by formulae (a2-D-1) to (a2-D-8), R a2In the structural units represented by formulae (a2-D-9) to (a2-D-16), the hydrogen atom corresponding to R a2 Specific examples of the structural unit (a2-D) include structural units in which the methyl group corresponding to the following formula is replaced with a hydrogen atom, etc. Among these, the structural units represented by formulae (a2-D-1) to (a2-D-8) are preferred, the structural units represented by formulae (a2-D-1) to (a2-D-4) are more preferred, and the structural unit represented by formula (a2-D-1) is even more preferred. When the resin (A) etc. contains the structural unit (a2-D), the content thereof is preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A) etc. Also, it is preferably 80 mol% or less, more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 10 to 70 mol%, and even more preferably 10 to 65 mol%.

[0103] <Structural unit (a3)> The lactone ring of the structural unit (a3) ​​may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or may be a condensed ring of a monocyclic lactone ring and another ring. Preferred examples include a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)).

[0104] The structural unit (a3) ​​is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3) or formula (a3-4). One of these may be contained alone, or two or more of them may be contained. TIFF2025026391000090.tif48155[In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and L a6are each independently -O- or *-O-(CH2) k3 It represents a group represented by -CO-O- (k3 represents an integer of any of 1 to 7). L a7 , -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -CO-OL a9 -CO-O- or *-OL a8 -O-CO-L a9 Represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * indicates the bonding site with the carbonyl group. R a18 , R a19 , R a20 and R a24 each independently represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 , R a23 and R a25 each independently represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents an integer of 0 to 5. q1 represents an integer of 0 to 3. r1 represents an integer of 0 to 3. w1 represents an integer of 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, multiple R a21 , R a22 , R a23 and / or R a25 may be the same or different.]

[0105] R a21 , R a22 , R a23 and Ra25 Examples of the aliphatic hydrocarbon group in include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a tert-butyl group. R a18 , R a19 , R a20 and R a24 Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R a18 , R a19 , R a20 and R a24 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group, and preferably includes an alkyl group having 1 to 4 carbon atoms, and more preferably includes a methyl group or an ethyl group. R a18 , R a19 , R a20 and R a24 Examples of the alkyl group having a halogen atom in the formula (I) include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. L a8 and L a9 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably -O- or *-O-(CH2) k3In the -CO-O- group, k3 is a group in which k3 is an integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and further preferably an oxygen atom. R a18 ~R a21 is preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group, or a methyl group. p1, q1 and r1 each independently represent an integer of preferably 0 to 2, and more preferably 0 or 1. In formula (a3-4), R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-OL a8 It is —CO—O—, and more preferably —O—, —O—CH2—CO—O— or —O—C2H4—CO—O—. w1 is preferably an integer of 0 to 2, and more preferably 0 or 1. In particular, the formula (a3-4) is preferably the formula (a3-4)'. TIFF2025026391000091.tif3848 (in the formula, R a24 , L a7 has the same meaning as above.)

[0106] Examples of the structural unit (a3) ​​include structural units derived from monomers described in JP 2010-204646 A, JP 2000-122294 A, and JP 2012-41274 A. Examples of the structural unit (a3) ​​include structural units represented by any one of formulas (a3-1-1), (a3-1-2), (a3-2-1), (a3-2-2), (a3-3-1), (a3-3-2), and (a3-4-1) to (a3-4-12), and in the structural unit, R in formulas (a3-1) to (a3-4) a18 , R a19 , R a20 and R a24 A structural unit in which a methyl group corresponding to the following formula is replaced with a hydrogen atom is preferred. TIFF2025026391000092.tif108164

[0107] When the resin (A) or the like contains the structural unit (a3), the total content thereof is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A) or the like. Also, 70 mol% or less is mentioned, preferably 65 mol% or less, more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 40 mol% or less, even more preferably 30 mol% or less, even more preferably 25 mol% or less, and even more preferably 20 mol% or less. Specifically, 1 to 70 mol% is mentioned, preferably 3 to 70 mol%, more preferably 3 to 65 mol%, even more preferably 5 to 65 mol%, even more preferably 5 to 60 mol%, and even more preferably 10 to 60 mol%. The content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3) or the structural unit (a3-4) is preferably 1 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A). It is also preferably 60 mol% or less, more preferably 55 mol% or less, even more preferably 50 mol% or less, even more preferably 40 mol% or less, even more preferably 30 mol% or less, even more preferably 25 mol% or less, and even more preferably 20 mol% or less. Specifically, it is preferably 1 to 60 mol%, more preferably 3 to 60 mol%, even more preferably 3 to 55 mol%, even more preferably 5 to 55 mol%, even more preferably 5 to 50 mol%, and even more preferably 10 to 50 mol%.

[0108] <Structural unit (a4)> The structural unit represented by formula (a4) is shown below. TIFF2025026391000093.tif3255[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having 1 to 24 carbon atoms and containing a halogen atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.]

[0109] R 42 Examples of the saturated hydrocarbon group represented by the formula (I) include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these groups. Examples of the chain saturated hydrocarbon group include linear alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, and an octadecyl group, and branched alkyl groups such as an isopropyl group and an isobutyl group. Examples of the monocyclic or polycyclic alicyclic saturated hydrocarbon group include monocyclic alicyclic saturated hydrocarbon groups which are monocyclic cycloalkyl groups, such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic saturated hydrocarbon groups which are polycyclic cycloalkyl groups, such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* represents a bonding site): TIFF2025026391000094.tif10146 Examples of groups formed by combinations include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, such as -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group. Examples of the alkanediyl group include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and hexane-1,6-diyl groups, and branched alkanediyl groups such as propane-1,2-diyl, butane-1,3-diyl, 2-methylpropane-1,2-diyl, 1-methylbutane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. The terminal of the branched alkanediyl group may be a methyl group. R 42 Examples of the halogen atom contained in the saturated hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 42Examples of the saturated hydrocarbon group in which -CH2- is replaced by -O- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), an oxy group (a group in which -CH2- in a methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced by -O-CO-), and an alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced by -CO-). ), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced with -CO-O-), alkanediyloxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -O-), alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -CO-), alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -CO-), cycloalkoxy group, cycloalkylalkoxy group, and the like, which are combinations of two or more of these groups. Examples of these substituted groups include the same as the groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0110] The structural unit (a4) is R 42 is preferably a saturated hydrocarbon group having a fluorine atom, and R 42However, examples of the structural unit (a4) which is a saturated hydrocarbon group having a fluorine atom include a structural unit represented by formula (a4-1) (hereinafter may be referred to as "structural unit (a4-1)"), a structural unit represented by formula (a4-2) (hereinafter may be referred to as "structural unit (a4-2)"), and a structural unit represented by formula (a4-3) (hereinafter may be referred to as "structural unit (a4-3)"). The structural unit represented by formula (a4-1) is a structural unit shown below. TIFF2025026391000095.tif4864[In formula (a4-1), R 41 represents a hydrogen atom or a methyl group. L 41 represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 42f represents a fluorine atom-containing alkanediyl group having 1 to 8 carbon atoms or a fluorine atom-containing cycloalkanediyl group having 3 to 12 carbon atoms. R 42f represents a hydrogen atom or a fluorine atom.

[0111] L 41 Examples of the alkanediyl group in the formula (I) include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, and butane-1,4-diyl, and branched alkanediyl groups such as ethane-1,1-diyl, propane-1,2-diyl, butane-1,3-diyl, 2-methylpropane-1,3-diyl, and 2-methylpropane-1,2-diyl. The terminal of the branched alkanediyl group may be a methyl group. L 42f Examples of the alkanediyl group having a fluorine atom in the formula (I) include linear alkanediyl groups having a fluorine atom, such as a methylene group having a fluorine atom, an ethylene group having a fluorine atom, a propane-1,3-diyl group having a fluorine atom, a butane-1,4-diyl group having a fluorine atom, a pentane-1,5-diyl group having a fluorine atom, a hexane-1,6-diyl group having a fluorine atom, a heptane-1,7-diyl group having a fluorine atom, and an octane-1,8-diyl group having a fluorine atom; Examples of branched alkanediyl groups having fluorine atoms include ethane-1,1-diyl groups having fluorine atoms, propane-1,1-diyl groups having fluorine atoms, propane-1,2-diyl groups having fluorine atoms, propane-2,2-diyl groups having fluorine atoms, pentane-2,4-diyl groups having fluorine atoms, 2-methylpropane-1,3-diyl groups having fluorine atoms, 2-methylpropane-1,2-diyl groups having fluorine atoms, pentane-1,4-diyl groups having fluorine atoms, and 2-methylbutane-1,4-diyl groups having fluorine atoms. The terminal of the branched alkanediyl group may be a methyl group which may have a fluorine atom. L 42f Examples of the cycloalkanediyl group having a fluorine atom in the formula (I) include monocyclic cycloalkanediyl groups having a fluorine atom, such as a cyclobutane-1,3-diyl group having a fluorine atom, a cyclopentane-1,3-diyl group having a fluorine atom, a cyclohexane-1,4-diyl group having a fluorine atom, a cyclohexene-3,6-diyl group having a fluorine atom, a cycloheptane-1,4-diyl group having a fluorine atom, and a cyclooctane-1,5-diyl group having a fluorine atom; Examples of polycyclic cycloalkanediyl groups having a fluorine atom include a norbornane-1,4-diyl group having a fluorine atom, a norbornane-2,5-diyl group having a fluorine atom, a 5-norbornene-2,3-diyl group having a fluorine atom, an adamantane-1,5-diyl group having a fluorine atom, and an adamantane-2,6-diyl group having a fluorine atom. L 42f The number of fluorine atoms contained in the alkanediyl group and cycloalkanediyl group having a fluorine atom in the above formula may be 1 or more, and is preferably 2 or more. L 42f The alkanediyl group and cycloalkanediyl group having a fluorine atom in the above formula (I) are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0112] L 42fExamples of the perfluoroalkanediyl group in the formula (I) include a difluoromethylene group, a perfluoroethylene group, a perfluoroethylfluoromethylene group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-2,2-diyl group, a perfluorobutane-1,4-diyl group, a perfluorobutane-2,2-diyl group, a perfluorobutane-1,2-diyl group, a perfluoropentane-1,5-diyl group, a perfluoropentane-2,2-diyl group, a perfluoropentane-3 ,3-diyl group, perfluorohexane-1,6-diyl group, perfluorohexane-2,2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1,7-diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3,4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1,8-diyl group, perfluorooctane-2,2-diyl group, perfluorooctane-3,3-diyl group, and perfluorooctane-4,4-diyl group. L 42f Examples of the perfluorocycloalkanediyl group in the formula (I) include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, and a perfluoroadamantanediyl group.

[0113] L 41 is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms, more preferably a single bond, a methylene group, or an ethylene group, and even more preferably a single bond or a methylene group. L 42f is preferably a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and even more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms. The structural unit (a4-1) may be any of the structural units shown below and R in the structural unit (a4-1) in the structural unit shown below. 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. TIFF2025026391000096.tif98159The structural unit represented by formula (a4-2) is the structural unit shown below. TIFF2025026391000097.tif5574[In formula (a4-2), R 41 represents a hydrogen atom or a methyl group. L 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. R 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, L 43f and R 43f At least one of L has a fluorine atom. 43f and R 43f The total number of carbon atoms in the molecule is limited to 21.

[0114] L 43f and R 43f Examples of the saturated hydrocarbon group in include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these groups. 43f and R 43f Examples of saturated hydrocarbon groups in the formula are L 43f and R 43f As long as the upper limit of the total number of carbon atoms in 42 Examples of the saturated hydrocarbon group include the same groups as the exemplified saturated hydrocarbon groups.

[0115] L 43f The saturated hydrocarbon group is preferably an alkanediyl group having 1 to 6 carbon atoms or a group represented by the formula (L43f-1). TIFF2025026391000098.tif14120[In formula (L43f-1), s represents 0 or 1. L 45f and L46f each independently represents a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may contain a fluorine atom. L 47f represents a single bond or a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may contain a fluorine atom. X 46f and X 47f each independently represents -O-, -CO-, -CO-O- or -O-CO-. However, L 45f , L 46f , L 47f , X 46f and X 47f The total number of carbon atoms is 7 or less. * and ** are binding sites, ** is -O-CO-R 43f This is the binding site for

[0116] L in the group represented by formula (L43f-1) 45f , L 46f and L 47f Examples of the divalent saturated hydrocarbon group represented by include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and a divalent saturated hydrocarbon group formed by combining an alkanediyl group and a divalent alicyclic saturated hydrocarbon group, etc. Specific examples include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, etc. It is preferred that s is 0.

[0117] Examples of the group represented by formula (L43f-1) include the following groups. In the following examples, * and ** each represent a bonding site, and ** represents -O-CO-R 43f This is the binding site for TIFF2025026391000099.tif47140

[0118] R 43f is preferably a saturated hydrocarbon group having a fluorine atom. In this case, examples of the structural unit represented by formula (a4-2) include structural units represented by formula (a4-2A) or (a4-2B). TIFF2025026391000100.tif69102 [In formula (a4-2A) and formula (a4-2B), R 41 and L 43f represents the same as in formula (a4-2). R 43fA represents a saturated hydrocarbon group having 1 to 20 carbon atoms and containing a fluorine atom. A 43f represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. X 43 represents **-O-CO- or **-CO-O-, and ** represents A 43f It represents the binding site with R 43fB represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may contain a fluorine atom. However, in formula (a4-2A), L 43f and R 43fA The total number of carbon atoms in formula (a4-2B) is 21 or less, and in formula (a4-2B), L 43f , A 43f , X 43 and R 43fB The total number of carbon atoms in A is 21 or less. 43f and R 43fB At least one of them has at least one fluorine atom. R 43fA The saturated hydrocarbon group of R is as long as the upper limit of the carbon number permits. 42 Examples of the saturated hydrocarbon groups include the saturated hydrocarbon groups exemplified by the above. R 43fA is preferably an alkyl group having 1 to 13 carbon atoms and containing a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms and containing a fluorine atom, or a group combining these, *-(CF2) n43f -R 42’ (* represents the bonding site with the carbonyl group. n43f represents an integer of 1 to 6. R42’ represents a hydrogen atom or a fluorine atom.) or a perfluorocycloalkyl group having 3 to 12 carbon atoms is more preferable. A 43f and R 43fB The saturated hydrocarbon group represented by R in formula (a4) is as large as possible within the upper limit of the number of carbon atoms. 42 Examples of the saturated hydrocarbon groups include the saturated hydrocarbon groups exemplified by the above. A 43f is preferably a divalent chain saturated hydrocarbon group which may have a fluorine atom, a divalent alicyclic saturated hydrocarbon group, or a combination thereof, more preferably a divalent chain saturated hydrocarbon group which has a fluorine atom, and further preferably a fluorinated alkanediyl group having 1 to 6 carbon atoms. R 43fB The saturated hydrocarbon group which may have a fluorine atom is preferably a chain saturated hydrocarbon group which may have a fluorine atom, an alicyclic saturated hydrocarbon group or a group combining these, more preferably an alkyl group having 1 to 12 carbon atoms which may have a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms or a group combining these, and more preferably a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4- More preferred are fluorinated alkyl groups such as an octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a heptyl group, a perfluoroheptyl group, an octyl group, and a perfluorooctyl group; a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a perfluorocyclohexyl group, an adamantyl group, an adamantylmethyl group, an adamantyldimethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, and a perfluoroadamantylmethyl group. In formula (a4-2B), *-A 43f -X 43 -R43fB An example of a structure that the group represented by the formula (I) can take is the following structure (* indicates the bonding site with the carbonyl group). TIFF2025026391000101.tif14170

[0119] The structural unit represented by formula (a4-2A) includes the structural units shown below and R in the structural unit represented by formula (a4-2A) in the structural units shown below. 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. TIFF2025026391000102.tif99168

[0120] The structural unit represented by formula (a4-2B) includes the structural units shown below and R in the structural unit represented by formula (a4-2B) in the structural units shown below. 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. TIFF2025026391000103.tif110163

[0121] The structural unit (a4) also includes a structural unit represented by formula (a4-3). TIFF2025026391000104.tif5576[In formula (a4-3), R 41 represents a hydrogen atom or a methyl group. L 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. R 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, L 44f and R 44f At least one of L has a fluorine atom. 44f and R 44f The total number of carbon atoms in the molecule is limited to 21.

[0122] L44f and R 44f Examples of the saturated hydrocarbon group in include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these groups. 44f and R 44f Examples of saturated hydrocarbon groups in the formula are L 43f and R 43f As long as the upper limit of the total number of carbon atoms in 42 Examples of the saturated hydrocarbon group include the same groups as the exemplified saturated hydrocarbon groups. L 44f is preferably an alkanediyl group having 1 to 14 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 -or-(CH2) j4 -CO-O-(CH2) j5 It is more preferably a group represented by the formula - (j1 to j5 each independently represent an integer of 1 to 6). It is also preferably an alkanediyl group having 1 to 4 carbon atoms (one -CH2- contained in the alkanediyl group may be replaced by -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced by -CO-O- or -O-CO-). R 44f is preferably a saturated hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, an alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms and having a fluorine atom, or a group combining these, further preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom.

[0123] Examples of the structural unit represented by formula (a4-3) include the following structural units and structural units represented by the following formulas: 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. TIFF2025026391000105.tif86170

[0124] When the resin (A) or the like contains the structural unit (a4), the content thereof is preferably 1 to 20 mol %, more preferably 2 to 15 mol %, and even more preferably 3 to 10 mol %, based on all structural units in the resin (A) or the like.

[0125] <Structural unit (a5)> The non-leaving hydrocarbon group contained in the structural unit (a5) may be a group containing a linear, branched or cyclic hydrocarbon group. Among these, the structural unit (a5) is preferably a group containing an alicyclic hydrocarbon group. An example of the structural unit (a5) is a structural unit represented by the formula (a5-1). TIFF2025026391000106.tif3351[In formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.]

[0126] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group, a norbornyl group, and the like. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, and a 2-ethylhexyl group. An example of the alicyclic hydrocarbon group having a substituent is a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an adamantyl group, a norbornyl group, or a cyclohexyl group. L 55 Examples of the divalent saturated hydrocarbon group in include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, and a divalent chain saturated hydrocarbon group is preferred. Examples of the divalent chain saturated hydrocarbon group include alkanediyl groups such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, and a pentanediyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as cyclopentanediyl and cyclohexanediyl. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include adamantanediyl and norbornanediyl. L 55 Examples of the divalent saturated hydrocarbon group represented by formula (L1-1) to formula (L1-4) include groups represented by formula (L1-2) to (L1-4). In the following formulae, * and ** each represent a bonding site, and * represents a bonding site with an oxygen atom. TIFF2025026391000107.tif18164[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents L x1 ) which represents the binding site with L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, L x1 and L x2 The total number of carbon atoms is 16 or less. In formula (L1-2), L x3represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, L x3 and L x4 The total number of carbon atoms is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, L x5 , L x6 and L x7 The total number of carbon atoms is 15 or less. In formula (L1-4), L x8 and L x9 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, L x8 , L x9 and W x1 The total number of carbon atoms is 15 or less. L x1 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, and more preferably a cyclohexanediyl group or an adamantanediyl group.

[0127] Examples of the group represented by formula (L1-1) include the divalent groups shown below. TIFF2025026391000108.tif37147 Examples of the group represented by formula (L1-2) include the divalent groups shown below. TIFF2025026391000109.tif23130 Examples of the group represented by formula (L1-3) include the divalent groups shown below. TIFF2025026391000110.tif16147 Examples of the group represented by formula (L1-4) include the divalent groups shown below. TIFF2025026391000111.tif13168L 55 is preferably a single bond or a group represented by formula (L1-1).

[0128] The structural unit (a5-1) may be any of the structural units shown below and R in the structural unit (a5-1) in the structural unit shown below. 51 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom. When the resin (A) or the like contains the structural unit (a5), the content thereof is preferably from 1 to 30 mol %, more preferably from 2 to 20 mol %, and even more preferably from 3 to 15 mol %, based on all structural units in the resin (A) or the like.

[0129] <Structural unit (a6)> The structural unit (a6) is a structural unit having a -SO2- group, and preferably has the -SO2- group in a side chain. The structural unit having a -SO2- group may have a linear structure having a -SO2- group, may have a branched structure having a -SO2- group, or may have a cyclic structure (monocyclic and polycyclic structure) having a -SO2- group. A structural unit having a cyclic structure having a -SO2- group is preferred, and a structural unit having a cyclic structure (sultone ring) containing -SO2-O- is more preferred.

[0130] The sultone ring may be represented by the following formula (T 1 -1), formula (T 1 -2), formula (T 1 -3) and the formula (T 1 The bonding site can be any position. The sultone ring may be monocyclic, but is preferably polycyclic. A polycyclic sultone ring refers to a bridged ring containing -SO2-O- as an atomic group constituting the ring, and is represented by the formula (T 1 -1) and the formula (T 1 The sultone ring is represented by the formula (T 1 As in the ring represented by formula (2), the atomic group constituting the ring may further contain a heteroatom in addition to -SO2-O-. Examples of the heteroatom include an oxygen atom, a sulfur atom, or a nitrogen atom, and an oxygen atom is preferred. TIFF2025026391000113.tif3087

[0131] The sultone ring may have a substituent. Examples of the substituent include an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, and an alkylcarbonyl group having 2 to 4 carbon atoms. Examples of halogen atoms include fluorine, chlorine, bromine and iodine atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, and a decyl group, and preferably an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group. Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group, and preferably a trifluoromethyl group. Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a 2-hydroxyethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Aralkyl groups include benzyl, phenethyl, phenylpropyl, naphthylmethyl and naphthylethyl groups. Examples of the alkoxycarbonyl group include groups in which an alkoxy group, such as a methoxycarbonyl group or an ethoxycarbonyl group, is bonded to a carbonyl group, and preferably, an alkoxycarbonyl group having 6 or less carbon atoms is used, and more preferably, a methoxycarbonyl group is used. Alkylcarbonyl groups include acetyl, propionyl and butyryl groups.

[0132] From the viewpoint of ease of production of the monomer from which the structural unit (a6) is derived, a sultone ring having no substituent is preferred. The sultone ring is preferably a ring represented by the following formula (T1'). TIFF2025026391000114.tif3072[In formula (T1'), X 11 represents an oxygen atom, a sulfur atom, or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms. ma represents an integer of 0 to 9. When ma is 2 or more, multiple R 41 may be the same or different. The binding site is at any position.] X 11 is preferably an oxygen atom or a methylene group, and more preferably a methylene group. R 41 Examples of the substituent include the same ones as the substituents on the sultone ring, and an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxyl group is preferred. ma is preferably 0 or 1, and more preferably 0.

[0133] Examples of the ring represented by formula (T1') include the following rings. The binding site may be any position. Among them, the binding site is preferably the 1st or 3rd position. It is preferable that the structural unit having a -SO2- group further has a group derived from a polymerizable group. Examples of the polymerizable group include a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, and a methacryloylthio group. Among these, the monomer from which the structural unit (a6) is derived is preferably a monomer having an ethylenically unsaturated bond, and more preferably a (meth)acrylic monomer.

[0134] The structural unit (a6) is preferably a structural unit represented by the formula (a6-0). TIFF2025026391000116.tif4077[In formula (a6-0), R x represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. A xx is an oxygen atom, -N(R c )- or a sulfur atom. A x represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH- contained in the saturated hydrocarbon group is -O-, -CO- or -N(R d )- may also be replaced. X 11 represents an oxygen atom, a sulfur atom, or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms. ma represents an integer of 0 to 9. When ma is 2 or more, multiple R41 may be the same or different. R c and R d each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.]

[0135] R x Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R x Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group. An alkyl group having 1 to 4 carbon atoms is preferred, and a methyl group or an ethyl group is more preferred. R x Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. R x is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0136] A x Examples of the divalent saturated hydrocarbon group include a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and may be a combination of two or more of these groups. Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, linear alkanediyl groups such as a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, a heptadecane-1,17-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group; branched alkanediyl groups such as butane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; monocyclic divalent alicyclic saturated hydrocarbon groups such as cycloalkanediyl groups, such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; Examples of the polycyclic divalent alicyclic saturated hydrocarbon groups include norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group. A x The bonding position of to the sultone ring may be any position, but is preferably the 1-position.

[0137] Examples of the structural unit (a6-0) include the following structural units. TIFF2025026391000117.tif93150

[0138] Of these, structural units represented by formulae (a6-1), (a6-2), (a6-6), (a6-7), (a6-8) and (a6-12) are preferred, and structural units represented by formulae (a6-1), (a6-2), (a6-7) and (a6-8) are more preferred. When the resin (A) or the like contains the structural unit (a6), the content thereof is preferably 1 to 50 mol %, more preferably 2 to 40 mol %, and even more preferably 3 to 30 mol %, based on all structural units in the resin (A) or the like.

[0139] <Structural unit (a7)> The resin (A) etc. may further contain a structural unit (hereinafter, sometimes referred to as "structural unit (a7)") that decomposes upon exposure to generate an acid. The structural unit (a7) functions in the same manner as an acid generator in the resist composition. Specific examples of the structural unit (a7) include structural units described in JP 2016-79235 A, and are preferably structural units having a sulfonate group or carboxylate group and an organic cation in the side chain, or a structural unit having a sulfonio group and an organic anion in the side chain. The structural unit having a sulfonate group or carboxylate group and an organic cation in the side chain is preferably a structural unit represented by formula (a7-A). TIFF2025026391000118.tif26124[In formula (a7-A), R a7 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a71 is a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR a71 -**, *-NR a71 -CO-O-**, *-O-CO-NR a71 -** or *-Ax-Ph-Ay-**. R a71 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one type of bond selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. * and ** represent binding sites, * represents R a7 represents the bonding site with the carbon atom to which it is bonded. La71 and L a72 each independently represents a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. X a72 represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, and *** represents L a71 It represents the binding site with na7 represents an integer of 0 to 2. When na7 is 2, the groups in the parentheses may be the same or different. RA - represents a sulfonate anion or a carboxyl anion. Z.A. + represents an organic cation.

[0140] R a7 and R a71 Examples of the alkyl group having 1 to 6 carbon atoms in the formula include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R a7 Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a7 Examples of the alkyl group having 1 to 6 carbon atoms and having a halogen atom in the formula (I) include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a dichloromethyl group, a triiodomethyl group, a diiodomethyl group, a tribromomethyl group, and a dibromomethyl group. R a7is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0141] X a71 is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025026391000119.tif3251[In formula (X10), Ax and Ay are R a7 or L a71 represents a bond type that bonds with, and represents one type of bond selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate bond, and an amide bond. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents an integer of 0 to 4, and when mx is an integer of 2 or more, multiple Rx's may be the same or different. When either Ax or Ay is a single bond, the other is preferably one selected from the group consisting of an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond. When either Ax or Ay is an amide bond, -CO-NR a71 A bond represented by - is preferred. The bonding position of Ay in the phenylene group is preferably the m-position or p-position relative to the bonding position of Ax, and more preferably the p-position. Among these, Rx is preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group or an ethyl group. mx is preferably 0, 1 or 2. X a71 Examples of the substituent include a single bond and a substituent represented by the following formula (X 10 -1)~Formula(X 10 -10) is a group represented by * -R a7represents the bonding site with the carbon atom to which L is bonded. a71 It represents the binding site with X 20 is -O- or -NR a71 - represents. TIFF2025026391000120.tif43161 formula (X 10 -1)~Formula(X 10 Specific examples of the group represented by -10) include the following groups. TIFF2025026391000121.tif88162 Among them, X a71 is a single bond and the formula (X 10 -1'), expression (X 10 -3')~expression(X 10 -9'), which is preferably a single bond or a group represented by the formula (X 10 -1'), expression (X 10 -4'), expression (X 10 -5'), expression (X 10 -6') and formula (X 10 -9'), a single bond, a group represented by the formula (X 10 -1'), a group represented by the formula (X 10 -5'), a group represented by the formula (X 10 -6') or formula (X 10 -9') is more preferable.

[0142] L a71 The hydrocarbon group is a group formed by removing one hydrogen atom from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, to form X. a71 and X a72 Also, L a72 The hydrocarbon group is a group formed by removing one hydrogen atom from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, to form X. a72 and R.A. - Examples of such groups include groups that bond to the L a71 and L a72Examples of the chain hydrocarbon group include a group in which one hydrogen atom has been removed from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentanedecyl group, and a heptadecyl group. Examples of the alkenyl group include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, and a nonenyl group. The chain hydrocarbon group preferably has 1 to 20 carbon atoms, more preferably 1 to 18 carbon atoms, and even more preferably 1 to 10 carbon atoms. L a71 and L a72 Examples of the alicyclic hydrocarbon group include a group in which one hydrogen atom has been removed from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cycloheptyl group, a cyclohexyl group, a cyclopentyl group, and a cyclooctyl group. L a71 and L a72Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a bridged structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are bonded by a spiro bond. Examples of the cycloalkyl group having a bridged structure include a norbornyl group and an adamantyl group. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group and a steroid group (steroid skeleton). Examples of the cycloalkyl group in which two rings are bonded by a spiro bond include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group is bonded by a spiro bond to a cycloalkyl group having 5 to 8 carbon atoms. A double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group include the following formula: TIFF2025026391000122.tif28158When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 3 to 12, and even more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the alicyclic hydrocarbon group preferably has 6 to 18 carbon atoms, and more preferably 7 to 12. L a71 and L a72 The aromatic hydrocarbon group may be a group in which one hydrogen atom has been removed from an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a fluorenyl group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 5 to 14, more preferably 6 to 14, and further preferably 6 to 10. L a71 and L a72 When --CH2-- in the hydrocarbon group is replaced with --O--, --CO--, --S-- or --SO2--, the number of carbon atoms before the replacement is regarded as the number of carbon atoms in the hydrocarbon group. L a71 and L a72Among these hydrocarbon groups, examples of groups in which -CH2- in a chain hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2- include a hydroxy group, a carboxy group, a thiol group, a carbonyl group, an oxy group, a thio group, a sulfonyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, etc. Examples of these replaced groups include the same groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. L a71 and L a72 Among the above hydrocarbon groups, examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2- include groups containing a cyclic ether, cyclic ketone, cyclic ester (lactone), cyclic thioether, cyclic acetal, and cyclic sulfonate ester (sultone) structure. Specific examples include alicyclic hydrocarbon groups represented by the following formula. The bonding position of the alicyclic hydrocarbon groups listed in the following formula may be any position. TIFF2025026391000123.tif46146L a71 and L a72 Among these hydrocarbon groups, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and examples of the group in which -CH2- is replaced by -O- or -S- include groups derived from a furan ring or a thiophene ring, respectively. L a71 and L a72 Examples of the group in which two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group are combined include a group in which the chain hydrocarbon group and the alicyclic hydrocarbon group are combined, a group in which the chain hydrocarbon group and the aromatic hydrocarbon group are combined, a group in which the alicyclic hydrocarbon group and the aromatic hydrocarbon group are combined, and a group in which the chain hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group are combined. The group in which the alicyclic hydrocarbon group and the aromatic hydrocarbon group are combined may be a condensed ring. L a71 and La72 The substituents which the hydrocarbon group may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a71 and L a72 When L is a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. a71 and L a72 The -CH2- of the chain hydrocarbon group contained in the hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2-, thereby forming L a71 and L a72 The hydrocarbon group may substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, or a sulfonyl group. na7 is preferably 0 or 1. ZA in formula (a7-A) + Examples of the cation include the same as the cation in the salt represented by formula (B1) etc.

[0143] In formula (a7-A), L a71 and L a72 When the hydrocarbon group is a saturated hydrocarbon group, in the formula (a7-B) described later, b7 The divalent linking group may include the same groups as those exemplified above. Examples of the structural unit represented by formula (a7-A) include a structural unit represented by formula (a7-A1). TIFF2025026391000124.tif30138[In formula (a7-A1), R a7 , X a71 , L a71 , X a72 , na7, R.A. - and Z.A. + has the same meaning as above. z7 represents an integer of 0 to 6. Q a7 , Qb7 , R z71 and R z72 each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms; when z7 is 2 or more, z71 and R z72 may be the same or different.] Q a7 , Q b7 , R z71 and R z72 As the perfluoroalkyl group having 1 to 6 carbon atoms or the alkyl group having 1 to 6 carbon atoms in R a7 Examples of the groups include the same groups as those exemplified in the above.

[0144] Examples of the structural unit represented by formula (a7-A) include the following structural units, R a7 Examples of the structural units include those in which the group corresponding to the methyl group in the above formula (I) is replaced with a hydrogen atom, a halogen atom (e.g., a fluorine atom) or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group, etc.), and the structural units described in WO 2012 / 050015. + represents an organic cation. TIFF2025026391000125.tif179162

[0145] TIFF2025026391000126.tif196157

[0146] The structural unit having a sulfonio group and an organic anion on the side chain is preferably a structural unit represented by formula (a7-B). TIFF2025026391000127.tif27104[In formula (a7-B), R a7 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A b7 represents a single bond or a divalent linking group. R b71 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. Rb72 and R b73 each independently represents a hydrocarbon group having 1 to 18 carbon atoms which may have a substituent; R b72 and R b73 may be bonded to each other to form a ring together with the sulfur atom to which they are attached. A - represents an organic anion. R a7 Examples of the halogen atom and the alkyl group which may have a halogen atom in the formula (a7-A) include the same halogen atom and the alkyl group which may have a halogen atom as in the formula (a7-A). R b71 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by the formula (I) include a phenylene group and a naphthylene group. R b72 and R b73 Examples of the hydrocarbon group represented by the formula (I) include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups formed by combining these groups include those similar to those described above. A b7 Examples of the divalent linking group represented by the formula (I) include divalent saturated hydrocarbon groups having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S- or -CO-. Examples of the divalent saturated hydrocarbon group include divalent chain saturated hydrocarbon groups such as linear or branched alkanediyl groups, and monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and combinations of these are also possible. Specifically, straight-chain alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, and dodecane-1,12-diyl group; divalent monocyclic alicyclic saturated hydrocarbon groups such as monocyclic cycloalkanediyl groups, such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group; and divalent polycyclic alicyclic saturated hydrocarbon groups, such as polycyclic cycloalkanediyl groups, such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group. Examples of saturated hydrocarbon groups in which -CH2- has been replaced with -O-, -S-, or -CO- include the following divalent groups. However, the number of carbon atoms before the -CH2- in the saturated hydrocarbon group is replaced with -O-, -S-, or -CO- is 17 or less. In the following formulas, * and ** represent binding sites, * represents R b71 It represents the binding site with TIFF2025026391000128.tif123162[where, X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X 4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0147] The structural unit containing a cation in formula (a7-B) includes the structural units represented by the following formula: a7 Examples of such structural units include those in which a group corresponding to the methyl group in the above formula (I) is replaced with a hydrogen atom, a halogen atom (e.g., a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group, etc.). JPEG2025026391000129.jpg72164

[0148] A - Examples of the organic anion represented by the formula (I) include a sulfonate anion, a sulfonylimide anion, a sulfonylmethide anion, and a carboxylate anion. - The organic anion represented by the formula (I) is preferably a sulfonate anion, and the sulfonate anion is more preferably the same as the anion exemplified for the acid generator (B). Examples of the sulfonylimide anion, sulfonylmethide anion, and carboxylate anion include the same anions exemplified for the acid generator (B).

[0149] Examples of the structural unit represented by formula (a7-B) include structural units represented below. TIFF2025026391000130.tif95157 When the resin (A) or the like contains the structural unit (a7), the structural unit (a7) may be contained alone or in combination of two or more kinds. The total content of the structural unit (a7) is preferably 1 to 30 mol%, more preferably 1 to 25 mol%, even more preferably 2 to 20 mol%, still more preferably 3 to 15 mol%, and even more preferably 3 to 10 mol%, based on the total structural units of the resin (A) or the like.

[0150] The resin (A) etc. is preferably a resin containing the structural unit (a1). In particular, the resin (Ap) is more preferably a resin consisting of the structural unit (IP), the structural unit (a1) and the structural unit (s), that is, a copolymer of the carboxylate (I), the monomer (a1) and the monomer (s). The resin (A) not containing the structural unit (IP) is preferably a resin consisting of the structural unit (a1) and the structural unit (s), that is, a copolymer of the monomer (a1) and the monomer (s). The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2) (preferably the structural unit having a cyclohexyl group or a cyclopentyl group), the structural unit represented by formula (a1-4), the structural unit represented by formula (a1-5), and the structural unit represented by formula (a1-6), more preferably at least two, and even more preferably at least two selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably the structural unit (a2-C) or the structural unit (a2-A). The structural unit (a3) ​​is preferably at least one selected from the group consisting of the structural unit represented by the formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-4).

[0151] Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using a monomer that leads to these structural units. The content of each structural unit contained in the resin (A) can be adjusted by the amount of monomer used for polymerization. The weight average molecular weight of the resin (Ap) and the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, even more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, even more preferably 15,000 or less), but may contain an oligomer having a weight average molecular weight smaller than this. In this specification, the weight average molecular weight is a value determined by gel permeation chromatography under the conditions described in the Examples. The structural unit (IP) may constitute a dimer, a trimer, or a compound or oligomer having a weight average molecular weight of less than 2,000.

[0152] [Carboxylic Acid Generator] The carboxylic acid generator of the present invention is a carboxylic acid generator containing a carboxylate (I) or a structural unit (IP). The structural unit (IP) can be contained as a compound or resin in which a plurality of units are polymerized. The carboxylate (I) or the structural unit (IP) of the present invention can act as a carboxylic acid generator in a resist composition. When the carboxylate (I) is used as a carboxylic acid generator in a resist composition, the carboxylic acid generator may contain only one type or two or more types of carboxylate (I). When the structural unit (IP) is used as a carboxylic acid generator in a resist composition, one type of compound or resin containing the structural unit (IP) may be used alone, or two or more types may be combined. The carboxylic acid generator of the present invention may contain both the carboxylate (I) and the structural unit (IP). As described below, the carboxylic acid generator of the present invention may further contain an acid generator known in the resist field other than the carboxylate (I) and / or the structural unit (IP) (hereinafter sometimes referred to as "acid generator (B)" or "compound (B)"), and / or a carboxylic acid generator known in the resist field other than the carboxylate (I) and / or the structural unit (IP). The acid generator (B) may be used alone or in combination of two or more. When the carboxylic acid generator of the present invention contains an acid generator (B) or the like, the ratio of the contents of the carboxylate (I) to the acid generator (B) or the like (mass ratio; carboxylate (I):acid generator (B)) is usually 1:99 to 100:0, preferably 1:99 to 99:1, more preferably 2:98 to 98:2, even more preferably 5:95 to 95:5, still more preferably 10:90 to 90:10, even more preferably 15:85 to 85:15, and particularly preferably 40:60 to 60:40.

[0153] [Resist Composition] The resist composition of the present invention contains a carboxylic acid generator. The carboxylic acid generator here may be a resin (Ap) containing a salt (I) or a structural unit (IP). The resist composition of the present invention contains at least one of the carboxylate (I) and the structural unit (IP), and may contain both. That is, the resist composition of the present invention may contain a carboxylic acid generator containing the structural unit (IP) of the present invention or the carboxylate (I) of the present invention. The structural unit (IP) may be in the form of either a compound or a resin. In other words, the resist composition of the present invention may contain a resin (Ap) and a carboxylate (I) as a carboxylic acid generator. The resist composition of the present invention preferably further contains a resin. The resin preferably contains a resin containing a structural unit (a1) having an acid labile group (hereinafter referred to as resin (A)). That is, (a) a resin (A) containing a carboxylate (I) and a structural unit (a1) having an acid labile group, (b) a resin (Ap) containing a structural unit (IP) and a structural unit (a1) having an acid labile group; (c) It is preferable to contain a resin (Ap) containing a structural unit (IP) and a resin (A) containing a structural unit (a1) having an acid labile group. Of these, it is preferable to have a resist composition containing the above (b). The resist composition of the present invention may contain two or more types of resins (A) and / or resins (Ap). The above (b) and (c) may further contain a salt (I). The resist composition of the present invention preferably further contains an acid generator (hereinafter sometimes referred to as "acid generator (B)" or "compound (B)"), a quencher (hereinafter sometimes referred to as "quencher (C)") and / or a solvent (hereinafter sometimes referred to as "solvent (E)") that are known in the resist field. The resist composition of the present invention may further contain a resin other than the above-mentioned resin (A) etc. <Carboxylic acid generator> The content of the carboxylate (I) of the present invention is preferably about 0.001 to 15 mass%, more preferably about 0.001 to 10 mass%, even more preferably about 0.001 to 8 mass%, and even more preferably about 0.005 to 7 mass%, based on the solid content of the resist composition. The content of the resin (Ap) of the present invention is preferably from 80 to 99% by mass, and more preferably from 90 to 99% by mass, based on the solid content of the resist composition.

[0154] <Resins other than Resin (A)> The resist composition of the present invention may contain a resin other than the resin (A) in combination. Examples of resins other than resin (Ap) and resin (A) include resin (AX) having the same structural units as resin (A) except that it does not contain the structural unit (a1) in the above-mentioned resin (A), and a resin containing structural unit (a4) and / or structural unit (a5) (however, it does not contain structural unit (IP) and structural unit (a1); hereinafter, this may be referred to as "resin (X)"). Resin (AX) may be a resin containing structural unit (a2), and preferably a resin containing structural unit (a2-A). In resin (AX), the content of structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, based on the total of all structural units of resin (AX). Also, it is preferably 80 mol% or less, and more preferably 70 mol% or less. Examples of structural units that may be further contained in the resin (X) include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. Among these, the resin (X) is preferably a resin consisting only of the structural unit (a4) and / or the structural unit (a5), and more preferably a resin consisting only of the structural unit (a4). When the resin (X) contains the structural unit (a4), the content of the structural unit (a4) in the resin (X) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more, based on the total of all structural units in the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. When the resin (X) contains the structural unit (a5), the content of the structural unit (a5) in the total of all structural units in the resin (X) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more. Also, it may be 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it may be 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. Also, when the resin (X) contains the structural unit (a4) and the structural unit (a5), the total content of the structural unit (a4) and the structural unit (a5) may be 40 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more, based on the total of all the structural units of the resin (X). Furthermore, it may be 100 mol% or less. Specifically, it may be 40 to 100 mol%, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and even more preferably 80 to 100 mol%.

[0155] Each structural unit constituting the resin (AX) and the resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using a monomer that derives these structural units. The content of each structural unit contained in the resin (AX) and the resin (X) can be adjusted by the amount of the monomer used for polymerization. The weight average molecular weight of resin (AX) and resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less), but may contain oligomers having a lower weight average molecular weight than this. The method for measuring the weight average molecular weight of resin (AX) and resin (X) is the same as that for resin (A) and the like.

[0156] When the resist composition of the present invention contains resin (X), the content thereof is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, even more preferably 1 to 40 parts by mass, still more preferably 1 to 30 parts by mass, and particularly preferably 1 to 8 parts by mass, per 100 parts by mass of the total of resin (A) and resin (Ap).

[0157] The total content of the resin (A) and the resin (Ap) in the resist composition is preferably 60% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 99% by mass or less, even more preferably 80% by mass or more and 99% by mass or less, and even more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. The total content of the resin (A) and the resin (Ap) in the resist composition is preferably 60% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 99% by mass or less, even more preferably 80% by mass or more and 99% by mass or less, and even more preferably 90% by mass or more and 99% by mass or less. When a resin other than the resin (A) is contained, the total content of the resin (A) and the resin other than the resin (A) is preferably 60% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 99% by mass or less, even more preferably 80% by mass or more and 99% by mass or less, and even more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. In this specification, the "solid content of the resist composition" refers to the total of the components excluding the solvent (E) described below from the total amount of the resist composition. The solid content of the resist composition and the resin content therein can be measured by known analytical means such as liquid chromatography or gas chromatography.

[0158] <Acid Generator (B)> The acid generator (B) may be either a nonionic compound or an ionic compound. Examples of nonionic compounds include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), and the like. Examples of ionic compounds include onium salts containing onium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Examples of anions of onium salts include sulfonate anion, benzenesulfonyl anion, sulfonylimide anion, sulfonylmethide anion, and carboxylate anion. The acid generator (B) may be a part of a structural unit constituting the resin contained in the resist composition, like the structural unit (a7) described above.

[0159] As the acid generator (B), compounds that generate acid by radiation, such as those described in JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Pat. No. 3,779,778, U.S. Pat. No. 3,849,137, German Patent No. 3914407, and European Patent No. 126,712, can be used. Compounds produced by known methods can also be used. The acid generator (B) can be used alone or in combination of two or more. The acid generator (B) may be an acid generator having an acid labile group. For example, the compound or resin serving as the acid generator may contain a partial structure that becomes an acid labile group.

[0160] A preferred embodiment of the acid generator (B) includes a salt represented by formula (B1) (hereinafter sometimes referred to as "salt (B1)" or "acid generator (B1)") and a salt represented by formula (B2) (hereinafter sometimes referred to as "salt (B2)" or "acid generator (B2)"). TIFF2025026391000131.tif1395 [In formula (B1), all symbols have the same meaning as defined above.] L b1 The (nb1+1)-valent hydrocarbon group is a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, or a monovalent group that is a combination of two or more of these groups, from which nb1 hydrogen atoms have been removed to form one or more L b2 Examples of such groups include groups that bond to the The hydrocarbon group preferably has 1-48 carbon atoms, more preferably 1-42 carbon atoms, even more preferably 1-36 carbon atoms, even more preferably 1-30 carbon atoms, and even more preferably 1-24 carbon atoms. Examples of the chain hydrocarbon group include a group in which nb1 hydrogen atoms have been removed from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentanedecyl group, and a heptadecyl group. Examples of the alkenyl group include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, and a nonenyl group. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 24, even more preferably 1 to 20, still more preferably 1 to 18, even more preferably 1 to 12, and even more preferably 1 to 10. Examples of the alicyclic hydrocarbon group include a group in which nb1 hydrogen atoms have been removed from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of polycyclic cycloalkyl groups include cycloalkyl groups having a bridged structure, cycloalkyl groups in which two or more rings are condensed, and cycloalkyl groups in which two rings are bonded by a spiro bond. Examples of cycloalkyl groups having a bridged structure include a norbornyl group and an adamantyl group. Examples of cycloalkyl groups in which two or more rings are condensed include a bicyclo[4,4,0]decane group and a steroid group (steroid skeleton). Examples of cycloalkyl groups in which two rings are bonded by a spiro bond include spirocyclic cycloalkyl groups in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group is bonded by a spiro bond to a cycloalkyl group having 5 to 8 carbon atoms. A double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, alicyclic hydrocarbon groups represented by the following formulas are included. TIFF2025026391000132.tif26168When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 24, more preferably 3 to 20, even more preferably 3 to 18, even more preferably 3 to 12, even more preferably 3 to 10, and even more preferably 3 to 8.When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 6 to 24, more preferably 6 to 20, even more preferably 6 to 18, even more preferably 6 to 12, and even more preferably 7 to 12. The aromatic hydrocarbon group may be an aryl group having nb1 hydrogen atoms removed therefrom, such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, or a fluorenyl group. More specifically, aromatic hydrocarbon groups represented by the following formulas are included. TIFF2025026391000133.tif1184 The number of carbon atoms in the aromatic hydrocarbon group is preferably 4 to 24, more preferably 4 to 20, even more preferably 4 to 18, even more preferably 5 to 14, even more preferably 5 to 10, and even more preferably 6 to 10. L b1 When --CH2-- in the hydrocarbon group is replaced with --O--, --CO--, --S-- or --SO2--, the number of carbon atoms before the replacement is regarded as the number of carbon atoms in the hydrocarbon group. L b1 Among the hydrocarbon groups in which -CH2- in a chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2-, there may be mentioned a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), an oxy group (a group in which -CH2- in a methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (an alkyl group in which -CH2- Examples of the substituted groups include -CH- at any position in the alkyl group, which is replaced with -CO-), alkylcarbonyloxy groups (wherein -CH-CH- at any position in the alkyl group is replaced with -CO-O-), alkanediyloxy groups (wherein -CH- at any position in the alkanediyl group is replaced with -O-), alkanediyloxycarbonyl groups (wherein -CH-CH- at any position in the alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl groups (wherein -CH- at any position in the alkanediyl group is replaced with -CO-), and alkanediylcarbonyloxy groups (wherein -CH-CH- at any position in the alkanediyl group is replaced with -CO-). Examples of the substituted groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. L b1 Among the above hydrocarbon groups, examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2- include groups containing structures such as cyclic ether, cyclic ketone, cyclic ester (lactone), cyclic thioether, cyclic acetal, and cyclic sulfonate ester (sultone). Specific examples include alicyclic hydrocarbon groups represented by the following formulas. The bonding position of the alicyclic hydrocarbon groups listed in the following formulas can be any position. TIFF2025026391000134.tif49165L b1 Among these hydrocarbon groups, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and examples of the group in which -CH2- is replaced by -O- or -S- include groups derived from a furan ring or a thiophene ring, respectively. Specific examples include aromatic hydrocarbon groups represented by the following formulas: TIFF2025026391000135.tif1326 Examples of the group that combines two or more groups selected from the chain hydrocarbon group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group include a group that combines the above chain hydrocarbon group with the above alicyclic hydrocarbon group, a group that combines the above chain hydrocarbon group with the above aromatic hydrocarbon group, a group that combines the above alicyclic hydrocarbon group with the above aromatic hydrocarbon group, and a group that combines the above chain hydrocarbon group with the above alicyclic hydrocarbon group with the above aromatic hydrocarbon group. The group that combines the alicyclic hydrocarbon group with the aromatic hydrocarbon group may be a condensed ring. L b2 The divalent hydrocarbon group includes a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group formed by combining two or more of these groups. A monovalent hydrocarbon group is formed by removing one hydrogen atom to give Y b1 Examples of such groups include groups that bond to the L b2 The divalent chain hydrocarbon group, the divalent alicyclic hydrocarbon group, the divalent aromatic hydrocarbon group, and the divalent group consisting of two or more of these groups are each, within the range permitted by the upper limit of the number of carbon atoms, L b1Examples of the monovalent hydrocarbon group include a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, and a monovalent group obtained by combining two or more of these groups from which one hydrogen atom has been removed. L b1 and L b2 Examples of the substituent that the hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L b1 and L b2 In the case where L is a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. b1 and L b2 The -CH2- of the chain hydrocarbon group contained in the hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2-, thereby forming L b1 and L b2 The hydrocarbon group may substantially have a substituent such as a hydroxy group, a carboxy group, a carbonyl group, an oxycarbonyl group, a carbonyloxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, or a sulfonyl group. L b1 and L b2 The number of substituents that may be possessed by the group is not particularly limited, and the group may have a plurality of substituents. Y b1 Examples of the cyclic hydrocarbon group include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group and an aromatic hydrocarbon group are combined. Y b1 The alicyclic hydrocarbon group and the aromatic hydrocarbon group are represented by L b1 Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups are the same as those exemplified in 1. When the alicyclic hydrocarbon groups and aromatic hydrocarbon groups do not have a substituent, they may be monovalent alicyclic hydrocarbon groups and aromatic hydrocarbon groups. Y b1 Examples of the substituent that the methyl group may have include a halogen atom, a cyano group, a hydroxy group, and a nitro group. Y b1 Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, and a hydrocarbon group having 1 to 18 carbon atoms that may have a halogen atom, a cyano group or a nitro group (-CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-). Y b1 The number of carbon atoms in the hydrocarbon group that may be contained in the cyclic hydrocarbon group is b1 The carbon number of the cyclic hydrocarbon group is not included in the carbon number of the cyclic hydrocarbon group. The halogen atoms are L b1 and L b2 Examples of the halogen atoms include the same halogen atoms as those exemplified as the substituent of the above. Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that may be substituted on the cyclic hydrocarbon group include chain hydrocarbon groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups combining these groups. Examples of the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups combining two or more of these groups include, within the range permitted by the upper limit of the carbon number, b1 Examples of the alkyl group include the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and the group obtained by combining two or more of these groups. b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms in which -CH2- is replaced with -O-, -S-, -CO- or -SO2- that may be substituted on the cyclic hydrocarbon group include, within the upper limit of the carbon number, b1 Examples of the hydrocarbon group include the same groups as those exemplified above in which -CH2- in the hydrocarbon group is replaced with -O-, -S-, -CO- or -SO2-. b1 The hydrocarbon group having 1 to 18 carbon atoms which the cyclic hydrocarbon group may have as a substituent may constitute a protecting group or leaving group (acid labile group or base labile group) generally used in the art.

[0161] Examples of the anion of the salt represented by formula (B1) include an anion represented by the following formula (B1-A1) (hereinafter, may be referred to as "anion (B1-A1)") or an anion represented by formula (B1-A2) (hereinafter, may be referred to as "anion (B1-A2)"). TIFF2025026391000136.tif31117[In formula (B1-A1), L b2 and Y b1 has the same meaning as in formula (B1). Q b1 , Q b2 , Q b3 and Q b4 each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. z1 represents an integer of 0 to 6. When z1 is 2 or more, the groups in the multiple parentheses may be the same or different. X 1 represents -O-CO-, -CO-O-, -O-CO-O- or -O-. L b3 represents a single bond or a (nb2+1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. nb2 represents an integer of 1 to 3. When nb2 is 2 or more, the groups in the parentheses may be the same or different.]

[0162] Q b1 , Q b2 , Q b3 and Q b4 Examples of the perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. Q b1 , Q b2 , Q b3 and Q b4Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. Q b1 and Q b2 Q b1 and Q b2 At least one of the groups preferably contains a fluorine atom or a perfluoroalkyl group, more preferably a fluorine atom or a perfluoroalkyl group, even more preferably a fluorine atom or a trifluoromethyl group, and even more preferably both are fluorine atoms. Q b3 and Q b4 are each preferably independently a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b3 is preferably a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b4 is preferably a hydrogen atom or a fluorine atom. z1 is preferably an integer of 0 to 3, and more preferably 0, 1 or 2. X 1 is preferably -O-CO- or -CO-O-.

[0163] L b3 The hydrocarbon group in the formula (B1) is, within the range permitted by the upper limit of the number of carbon atoms, b1 The same hydrocarbon groups as those exemplified above are included. L b3is preferably a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent (-CH2- contained in the aromatic hydrocarbon group may be replaced with -O- or -S-), or a group consisting of a combination of two or more of these groups, and more preferably a single bond, a chain hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following formula (Lb3-1). When -CH2- in the chain hydrocarbon group is replaced by -O- or -CO-, the number is preferably 1 to 4, and it is preferable that one -CH2-CH2- in the chain hydrocarbon group is replaced by -O-CO- or -CO-O-, or one -CH2-CH2-CH2- in the chain hydrocarbon group is replaced by -O-CO-O-. TIFF2025026391000137.tif1582[In formula (Lb3-1), nb2 has the same meaning as in formula (B1-A1). L b31 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent. W b3 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent. * and ** represent binding sites, * represents X 1 represents the binding site for In formula (Lb3-1), L b31 The chain hydrocarbon group of L is as long as the upper limit of the carbon number allows. b1Examples of the chain hydrocarbon groups include the same groups as those exemplified above. In formula (Lb3-1), W b3 The alicyclic and aromatic hydrocarbon groups of L are as long as the upper limit of the carbon number permits. b1 Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups are the same as those exemplified by 1. In formula (Lb3-1), L b31 The substituents which the chain hydrocarbon group may have and W b1 The substituents that the alicyclic hydrocarbon group and aromatic hydrocarbon group may have are b1 The substituents which the hydrocarbon group may have include the same groups as those exemplified above. L b31 is preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, W b3 As the alicyclic hydrocarbon group and aromatic hydrocarbon group of the above, the alicyclic hydrocarbon group and aromatic hydrocarbon group represented below are preferable. In the alicyclic hydrocarbon group and aromatic hydrocarbon group represented below, * and ** represent a bonding site, * represents X 1 Or L b31 represents a bonding site with L, and ** represents a hydrogen atom, a substituent, or L b2 At least one ** represents a binding site for L b2 represents a bonding site with the alicyclic hydrocarbon group. In the alicyclic hydrocarbon groups represented below, -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-. When -CH2- contained in the alicyclic hydrocarbon group is replaced with -O-, -S-, -CO- or -SO2-, it is preferable that an ether ring, an ester ring (lactone), a carbonate ring, a sulfonate ring (sultone) or an acetal ring is formed. In the formula (B1-A1) of TIFF2025026391000138.tif37165, L b2is preferably a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and is preferably a single bond, -O-, -O-CO-, -CO-O-, -O-CO-O- or *-L b21 -X 2 -L b22 -**(L b21 and L b22 One of X represents a chain hydrocarbon group having 1 to 6 carbon atoms, and the other represents a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms. 2 represents -O-, -CO-O-, -O-CO-, or -O-CO-O-. * and ** represent binding sites, and ** represents Y b1 where L b21 , X 2 and L b22 The total number of carbon atoms is 12 or less. In formula (B1-A1), Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and even more preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, it is preferably a group represented by the following formulae (Y1) to (Y36). In formulae (Y1) to (Y36), R Yb is a hydrogen atom or Y b1 Among the substituents that the cyclic hydrocarbon group may have, R represents an alkyl group having 1 to 4 carbon atoms. Yc is a hydrogen atom or Y b1 represents a substituent that the cyclic hydrocarbon group may have, and * represents L b2The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formulae are not specifically shown in the following formulae, but may also be bonded to Y b1 The cyclic hydrocarbon group may have a substituent. TIFF2025026391000139.tif82158 The anion represented by formula (B1-A1) is preferably an anion represented by formula (B1-A1-1) to formula (B1-A1-85) [hereinafter, may be referred to as "anion (B1-A1-1)" depending on the formula number. ], and more preferably an anion represented by any of formula (B1-A1-1) to formula (B1-A1-4), formula (B1-A1-9), formula (B1-A1-10), formula (B1-A1-24) to formula (B1-A1-33), formula (B1-A1-36) to formula (B1-A1-40), and formula (B1-A1-47) to formula (B1-A1-85). TIFF2025026391000140.tif234161

[0164] TIFF2025026391000141.tif249153

[0165] TIFF2025026391000142.tif254163

[0166] In formulae (B1-A1-1) to (B1-A1-85), R i2 ~R i7 are each independently, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. i8 L is, for example, a chain hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. A41 Q is a single bond or an alkanediyl group having 1 to 4 carbon atoms. b1 and Q b2 has the same meaning as above. Specific examples of the anion represented by formula (B1-A1) include the anions described in JP-A-2010-204646.

[0167] Preferred examples of the anion represented by formula (B1-A1) include the anions represented by formulae (B1a-1) to (B1a-70). Among these, preferred are the anions represented by formulae (B1a-1) to (B1a-4), (B1a-7) to (B1a-11), (B1a-14) to (B1a-30), and (B1a-35) to (B1a-70). TIFF2025026391000143.tif183158

[0168] TIFF2025026391000144.tif252160

[0169] TIFF2025026391000145.tif69163

[0170] The anion represented by formula (B1-A2) is represented by the following formula: TIFF2025026391000146.tif23100[In formula (B1-A2), L b2 and Y b1 has the same meaning as in formula (B1). R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkyl group may be replaced with -O- or -CO-. nb4 represents an integer of 1 to 5. When nb4 is 2 or more, the groups in the multiple parentheses may be the same or different. nb3 represents an integer of 0 to 4. When nb3 is 2 or more, a plurality of R b1 may be the same or different from each other. However, 1≦nb4+nb3≦5 is satisfied.

[0171] In formula (B1-A2), L b2 Hydrocarbon groups and Y b1 Examples of the cyclic hydrocarbon group include, within the upper limit of the carbon number, L in formula (B1). b2 Hydrocarbon groups and Y b1Examples of the cyclic hydrocarbon group are the same as those of L. b2 Hydrocarbon radical, Y b1 The substituents which the methyl group and the cyclic hydrocarbon group may have are also defined as follows: b2 Hydrocarbon radical, Y b1 Examples of the substituent that the methyl group and the cyclic hydrocarbon group may have include the same as those mentioned above. These hydrocarbon groups, methyl groups and cyclic hydrocarbon groups may have one or more substituents. In formula (B1-A2), L b2 is preferably a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and more preferably *-CO-OL b41 -(L b41 is a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms, and -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-. * is SO3 - It represents the bonding site with the benzene ring to which L is attached. b41 is preferably a single bond or a chain hydrocarbon group having 1 to 3 carbon atoms, and more preferably *--CO--O--. Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and Y in formula (B1-A1) is b1 Or L b1 More preferably, it is an alicyclic hydrocarbon group or an aromatic hydrocarbon group exemplified by the following: Specifically, it is preferably a group represented by the above formulae (Y1) to (Y36), and more preferably a group represented by the above formulae (Y1) to (Y19). In formula (B1-A2), nb4 is preferably any integer of 1 to 4, more preferably any integer of 1 to 3, further preferably 1 or 2, and further more preferably 2. When nb4 is 1 or 2, -L b2 -Y b1 The bond position of SO3 - It is preferable that the structure shown below is substituted at the m-position of the benzene ring relative to the bonding position of the above. TIFF2025026391000147.tif28107[In the above formula, L b2 , Y b1 , R b1 , nb3 has the same meaning as in formula (B1-A2). If nb4 is 2 or more, multiple L b2 and Y b1 are preferably the same groups.

[0172] R b1 Examples of the alkyl group having 1 to 6 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 4, and more preferably 1 to 3. R b1 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkyl group in which -CH2- is replaced with -O- or -CO- include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an oxy group, a carbonyl group, etc. Specific examples of these are the same as those mentioned above. R b1are each independently preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), more preferably a fluorine atom, an iodine atom, or an alkyl group having 1 to 3 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), and further preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group, or a methyl group. nb3 is preferably an integer of 0 to 3, and more preferably an integer of 0 to 2. In one embodiment, nb3 is preferably 0. In another embodiment, nb3 is preferably 1 or 2. When nb3 is 1, R b1 is preferably a halogen atom, and R b1 is more preferably a fluorine atom or an iodine atom. When nb3 is 2, two R b1 It is preferable that one of R is a halogen atom and the other is a halogen atom or an alkyl group having 1 to 4 carbon atoms. b1 It is more preferable that one of them is a fluorine atom or an iodine atom, and the other is a fluorine atom, an iodine atom, or an alkyl group having 1 to 3 carbon atoms.

[0173] Examples of the anion represented by formula (B1-A2) include the following anions. Among them, the anions represented by formulae (B2a-1) to (B2a-20) are preferred, and the anions represented by formulae (B2a-1) to (B2a-11) and (B2a-16) to (B2a-20) are more preferred. The following anions are preferred in the case of some R b1 is omitted, and may contain substituents not shown. TIFF2025026391000148.tif117156

[0174] TIFF2025026391000149.tif13100[In formula (B2), A 1 represents a nitrogen atom or a carbon atom. L b2represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be rep...

Claims

1. A carboxylic acid generator comprising a carboxylate represented by formula (I) or a structural unit represented by formula (IP). [In formula (I) and formula (IP), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1, and when X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0. R １Ａ and R １Ｂ are each independently *-X １ -R １０ , *-X １ -L １１ -X ２ -R １０ represents R ４ is bonded to a benzene ring or R ７ represents the bonding site with the benzene ring to which it is attached. X １ and X ２ are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (wherein * represents a benzene ring or L １１ ) represents the binding site with L １１ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and the —CH 2 - is -O-, -S-, -SO ２ It may be replaced by --or --CO--. R １０ represents an acid-stable hydrocarbon group. R ４ represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, and the —CH 2 - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced by -. R ７ , R ８ and R ９ each independently represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, 2 - is -O-, -S-, -CO-, -SO- or -SO ２ When X is a sulfur atom, R ７ and R ８ Or R ８ and R ９ is bonded to S ＋ The R forming the ring may form a ring containing ７ and R ８ Or R ８ and R ９ , S ＋ The —CH 2 - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced by -. m1A represents an integer of 0 to 5, and when m1A is 2 or more, a plurality of R １Ａ may be the same or different from each other. m1B represents an integer of 0 to 4, and when m1B is 2 or more, a plurality of R １Ｂ may be the same or different, provided that either m1A or m1B is an integer of at least 1. m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R ４ may be the same or different, and satisfy 0≦m1A+m4≦5. m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R ７ may be the same or different, and satisfy 0≦m1B+m7≦4. m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R ８ may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R ９ may be the same or different from each other. X ０ represents a single bond or a hydrocarbon group having 1 to 72 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. R ｂｂ１ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X １０ represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR ３ -**, *-NR ３ -CO-O-**, *-O-CO-NR ３ -** or *-Ax-Ph-Ay-**. R ３ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. * and ** represent binding sites, * represents R ｂｂ１ represents the bonding site with the carbon atom to which it is bonded. L １０ represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ - or -CO- may be substituted.]

2. R １０ 2. The carboxylic acid generator according to claim 1, wherein the acid-stable hydrocarbon group is a group represented by formula (3a): [In formula (3a), R １ａ and R ２ａ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms; １ａ and R ２ａ are bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. R ３ａ represents a hydrogen atom, or R １ａ and R ２ａ and R ３ａ are bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. * indicates a binding site.]

3. m1A is an integer of 1 to 3, and R １Ａ But -O-CO-OR １０ Or -O-L １１ -C-O-R １０ The carboxylic acid generator according to claim 1,

4. X ０ is a single bond, an aliphatic hydrocarbon group having 1 to 72 carbon atoms, or a hydrocarbon group having 6 to 72 carbon atoms including an aromatic hydrocarbon group having 6 to 36 carbon atoms, The aliphatic hydrocarbon group and —CH contained in the hydrocarbon group ２ - is -O-, -S-, -CO- or -SO ２ 2. The carboxylic acid generator according to claim 1, wherein the aliphatic hydrocarbon group, the aromatic hydrocarbon group and the hydrocarbon group each may have a substituent.

5. X ０ is an open chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, a group in which an open chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 36 carbon atoms are combined, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a group in which an aromatic hydrocarbon group having 6 to 36 carbon atoms and an open chain hydrocarbon group having 1 to 18 carbon atoms are combined, the chain hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group; The —CH group contained in the chain hydrocarbon group and the alicyclic hydrocarbon group ２ - is -O-, -S-, -SO ２ The carboxylic acid generator according to claim 1, which may be replaced by - or -CO-.

6. X ０ but, an alkanediyl group having 1 to 6 carbon atoms; a cycloalkanediyl group having 5 to 6 carbon atoms, an adamantanediyl group, a norbornanediyl group, a phenylene group, COO － and a cycloalkanediyl group, adamantanediyl group, norbornanediyl group or phenylene group having 5 to 6 carbon atoms bonded to the alkanediyl group; or COO － a polycyclic alicyclic hydrocarbon group in which a cycloalkanediyl group, adamantanediyl group or norbornanediyl group having 5 to 6 carbon atoms bonded to a cycloalkanediyl group having 5 to 8 carbon atoms is bonded in a spiro structure; The —CH contained in the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group, and the norbornanediyl group ２ The carboxylic acid generator according to claim 1, wherein - may be replaced by -O- or -CO-, and the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group, the norbornanediyl group and the phenylene group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group.

7. X １０ is a single bond or a group represented by the formula (X １０ -1) ~Formula (X １０ 2. The carboxylic acid generator according to claim 1, wherein the carboxylic acid generator is a group represented by any one of the following formulas: [Formula (X １０ -1) ~ type (X １０ -10) * and ** are binding sites, * is R ｂｂ１ represents the bonding site with the carbon atom to which it is bonded. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents an integer of 0 to 4. X ２０ is -O- or -NR ３ Represents -. R ３ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

8. X １０ is a single bond or a group represented by the formula (X １０ -1'), formula (X １０ -3') ~Formula (X １０ -8') and formula (X １０ 2. The carboxylic acid generator according to claim 1, wherein the carboxylic acid generator is a group represented by any one of the following formulas: [Formula (X １０ -1'), formula (X １０ -3') ~Formula (X １０ -8') and formula (X １０ -10') medium, * and ** are binding sites, * is R ｂｂ１ represents the bonding site with the carbon atom to which it is bonded.

9. X １０ is a single bond or a group represented by the formula (X １０ -1'), formula (X １０ -5'), formula (X １０ -6') and formula (X １０ 9. The carboxylic acid generator according to claim 8, wherein the carboxylic acid generator is a group represented by any one of the following formulas:

10. L １０ is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms and a cyclic hydrocarbon group having 3 to 18 carbon atoms, The cyclic hydrocarbon group may have a substituent, and the alkanediyl group and the -CH 2 - is -O-, -S-, -SO ２ The carboxylic acid generator according to claim 1, which may be replaced by - or -CO-.

11. A resist composition comprising the carboxylic acid generator according to any one of claims 1 to 10.

12. A carboxylate represented by formula (I) The resist composition according to claim 11, further comprising a resin that contains a structural unit (a1) having an acid labile group.

13. Contains a resin containing a structural unit represented by formula (IP), The resist composition according to claim 11, wherein the resin containing the structural unit represented by formula (IP) further contains a structural unit (a1) having an acid labile group.

14. The resist composition according to claim 13, further comprising a carboxylate represented by formula (I).

15. The resist composition according to claim 12, wherein the structural unit (a1) having an acid labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). [In formula (a1-0), formula (a1-1) and formula (a1-2), L ａ０１ , L ａ１ and L ａ２ are each independently -O- or *-O-(CH ２ ) ｋ１ represents --CO--O--, k1 represents an integer of 1 to 7, and * represents the bonding site with --CO--. R ａ０１ , R ａ４ and R ａ５ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ０２ , R ａ０３ and R ａ０４ each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, and the alkyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may contain a halogen atom. R ａ６ and R ａ７ each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom. m1′ represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. [In formula (a1-4), R ａ１ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ１７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ１１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the —CH ２ - is -O-, -CO- or -NR ａ１８ May be replaced with -. R ａ１８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ１ represents a single bond or --CO--. R a34 and R a35 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the hydrocarbon group and the -CH 2 - may be replaced by -O- or -S-. na1 represents an integer of 1 to 5, and when na1 is 2 or more, the groups in the parentheses may be the same or different. na11 represents an integer of 0 to 4, and when na11 is 2 or more, a plurality of R ａ１７ may be the same or different from each other. mc represents an integer of 0 to 2. [In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Z a1 is a single bond or *-(CH 2 ) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents --O-- or --S--. s1 represents an integer of 1 to 3. s1′ represents an integer of 0 to 3.] [In formula (a1-6), R a61 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a6２ , R a63 and R a6４ each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a6２ and R a63 are bonded to each other to form, together with the carbon atoms to which they are attached, a ring having 3 to 20 carbon atoms. X a61 is a single bond, -CO-O-* or -CO-NR 5 - represents *, * represents a bonding site with Ar, R 5 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X a62 is a single bond, *-O-L a61 - or *-CO-OL a62 -, * represents a bonding site with Ar, L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.]

16. 13. The resist composition according to claim 12, wherein the resin containing the structural unit (a1) having an acid labile group further contains a structural unit represented by formula (a2-A). [In formula (a2-A), R a２ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a27 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the —CH ２ - is -O-, -CO- or -NR ａ２８ It may be replaced with -. R ａ２８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ２ represents a single bond or --CO--. nA2 represents an integer of 1 to 5. When nA2 is 2 or more, the groups in the parentheses may be the same or different. na21 represents an integer of 0 to 4. When na21 is 2 or more, a plurality of R a27 may be the same or different from each other. mc represents an integer of 0 to 2.

17. Further containing an acid generator, 12. The resist composition according to claim 11, wherein the acid generator comprises a salt represented by formula (B1). [In formula (B1), L b1 represents a single bond or a (nb1+1)-valent hydrocarbon group which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO 2 It may be replaced with -. L b2 represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH 2 - is -O-, -S-, -CO- or -SO 2 It may be replaced by -. Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO 2 It may be replaced by --or --CO--. nb1 represents an integer of 1 to 6. When nb1 is 2 or more, the groups in the parentheses may be the same or different. Z ＋ represents an organic cation.

18. (1) A step of applying the resist composition according to claim 11 onto a substrate; (2) A step of drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising the steps of:

19. A carboxylate represented by formula (I): [In formula (I), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1, and when X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0. R １Ａ and R １Ｂ are each independently *-X １ -R １０ , *-X １ -L １１ -X ２ -R １０ represents R ４ is bonded to a benzene ring or R ７ represents the bonding site with the benzene ring to which it is attached. X １ and X ２ are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (wherein * represents a benzene ring or L １１ ) represents the binding site with L １１ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and the —CH 2 - is -O-, -S-, -SO ２ It may be replaced by --or --CO--. R １０ represents an acid-stable hydrocarbon group. R ４ represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, and the —CH 2 - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced by -. R ７ , R ８ and R ９ each independently represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, 2 - is -O-, -S-, -CO-, -SO- or -SO ２ When X is a sulfur atom, R ７ and R ８ Or R ８ and R ９ is bonded to S ＋ The R forming the ring may form a ring containing ７ and R ８ Or R ８ and R ９ , S ＋ The —CH 2 - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced by -. m1A represents an integer of 0 to 5, and when m1A is 2 or more, a plurality of R １Ａ may be the same or different from each other. m1B represents an integer of 0 to 4, and when m1B is 2 or more, a plurality of R １Ｂ may be the same or different, provided that either m1A or m1B is an integer of at least 1. m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R ４ may be the same or different, and satisfy 0≦m1A+m4≦5. m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R ７ may be the same or different, and satisfy 0≦m1B+m7≦4. m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R ８ may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R ９ may be the same or different from each other. X ０ represents a single bond or a hydrocarbon group having 1 to 72 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. R ｂｂ１ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X １０ represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR ３ -**, *-NR ３ -CO-O-**, *-O-CO-NR ３ -** or *-Ax-Ph-Ay-**. R ３ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. * and ** represent binding sites, * represents R ｂｂ１ represents the bonding site with the carbon atom to which it is bonded. L １０ represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ - or -CO- may be substituted.]

20. R １０ The carboxylate according to claim 19, wherein the acid-stable hydrocarbon group is a group represented by formula (3a): [In formula (3a), R １ａ and R ２ａ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms; １ａ and R ２ａ are bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. R ３ａ represents a hydrogen atom, or R １ａ and R ２ａ and R ３ａ are bonded to each other to form a hydrocarbon ring having 3 to 36 carbon atoms which may have an alkyl group having 1 to 12 carbon atoms. * indicates a binding site.]

21. m1A is an integer of 1 to 3, R １Ａ But -O-CO-OR １０ Or -O-L １１ -C-O-R １０ 21. The carboxylate according to claim 19 or 20,

22. X ０ is a single bond, an aliphatic hydrocarbon group having 1 to 72 carbon atoms, or a hydrocarbon group having 6 to 72 carbon atoms including an aromatic hydrocarbon group having 6 to 36 carbon atoms, The aliphatic hydrocarbon group and the —CH ２ - is -O-, -S-, -CO- or -SO ２ The carboxylate according to claim 19 or 20, wherein the aliphatic hydrocarbon group, the aromatic hydrocarbon group and the hydrocarbon group each optionally have a substituent.

23. X ０ is an open chain hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, a group in which an open chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 36 carbon atoms are combined, an aromatic hydrocarbon group having 6 to 36 carbon atoms, or a group in which an aromatic hydrocarbon group having 6 to 36 carbon atoms and an open chain hydrocarbon group having 1 to 18 carbon atoms are combined, the chain hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group; The —CH group contained in the chain hydrocarbon group and the alicyclic hydrocarbon group ２ - is -O-, -S-, -SO ２ The carboxylate according to claim 19 or 20, which may be replaced by - or -CO-.

24. X ０ but, an alkanediyl group having 1 to 6 carbon atoms; a cycloalkanediyl group having 5 to 6 carbon atoms, an adamantanediyl group, a norbornanediyl group, a phenylene group, COO － and a cycloalkanediyl group, adamantanediyl group, norbornanediyl group or phenylene group having 5 to 6 carbon atoms bonded to the alkanediyl group; or COO － a polycyclic alicyclic hydrocarbon group in which a cycloalkanediyl group, adamantanediyl group or norbornanediyl group having 5 to 6 carbon atoms bonded to a cycloalkanediyl group having 5 to 8 carbon atoms is bonded in a spiro structure; The —CH contained in the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group, and the norbornanediyl group ２ The carboxylate according to claim 19 or 20, wherein - may be replaced by -O- or -CO-, and the alkanediyl group, the cycloalkanediyl group, the adamantanediyl group, the norbornanediyl group and the phenylene group may have a halogen atom, a perfluoroalkyl group having 1 to 4 carbon atoms, a hydroxy group or a hydroxymethyl group.

25. X １０ is a single bond or a group represented by the formula (X １０ -1) ~Formula (X １０ The carboxylate according to claim 19 or 20, wherein the carboxylate is a group represented by any one of the following formulas: [Formula (X １０ -1) ~ type (X １０ -10) * and ** are binding sites, * is R ｂｂ１ represents the bonding site with the carbon atom to which it is bonded. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents an integer of 0 to 4. X ２０ is -O- or -NR ３ Represents -. R ３ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

26. X １０ is a single bond or a group represented by the formula (X １０ -1'), formula (X １０ -3') ~Formula (X １０ -8') and formula (X １０ 21. The carboxylate according to claim 19, wherein the carboxylate is a group represented by any one of the following formulas: [Formula (X １０ -1'), formula (X １０ -3') ~Formula (X １０ -8') and formula (X １０ -10') medium, * and ** are binding sites, * is R ｂｂ１ represents the bonding site with the carbon atom to which is bonded.

27. X １０ is a single bond or a group represented by the formula (X １０ -1'), formula (X １０ -5'), formula (X １０ -6') and formula (X １０ The carboxylate according to claim 26, wherein the carboxylate is a group represented by any one of the following formulas:

28. L １０ is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms and a cyclic hydrocarbon group having 3 to 18 carbon atoms, The cyclic hydrocarbon group may have a substituent, and the alkanediyl group and the -CH 2 - is -O-, -S-, -SO ２ The carboxylate according to claim 19 or 20, which may be replaced by - or -CO-.

29. A resin containing a structural unit represented by formula (IP): [In the formula (IP), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1, and when X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0. R １Ａ and R １Ｂ are each independently *-X １ -R １０ , *-X １ -L １１ -X ２ -R １０ represents R ４ is bonded to a benzene ring or R ７ represents the bonding site with the benzene ring to which it is attached. X １ and X ２ are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (wherein * represents a benzene ring or L １１ ) represents the binding site with L １１ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and the —CH 2 - is -O-, -S-, -SO ２ It may be replaced by --or --CO--. R １０ represents an acid-stable hydrocarbon group. R ４ represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, and the —CH 2 - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced by -. R ７ , R ８ and R ９ each independently represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, 2 - is -O-, -S-, -CO-, -SO- or -SO ２ When X is a sulfur atom, R ７ and R ８ Or R ８ and R ９ is bonded to S ＋ The R forming the ring may form a ring containing ７ and R ８ Or R ８ and R ９ , S ＋ The —CH 2 - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced by -. m1A represents an integer of 0 to 5, and when m1A is 2 or more, a plurality of R １Ａ may be the same or different from each other. m1B represents an integer of 0 to 4, and when m1B is 2 or more, a plurality of R １Ｂ may be the same or different, provided that either m1A or m1B is an integer of at least 1. m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R ４ may be the same or different, and satisfy 0≦m1A+m4≦5. m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R ７ may be the same or different, and satisfy 0≦m1B+m7≦4. m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R ８ may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R ９ may be the same or different from each other. X ０ represents a single bond or a hydrocarbon group having 1 to 72 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. R ｂｂ１ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X １０ represents a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR ３ -**, *-NR ３ -CO-O-**, *-O-CO-NR ３ -** or *-Ax-Ph-Ay-**. R ３ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond. * and ** represent binding sites, * represents R ｂｂ１ represents the bonding site with the carbon atom to which it is bonded. L １０ represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ - or -CO- may be substituted.]

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