Acid generator, salt, resist composition, and method for producing resist pattern

Abstract

To provide an acid generator and a resist composition capable of producing a resist pattern having good line edge roughness.SOLUTION: The acid generator contains a salt represented by formula (I). [wherein, m10 is an integer of 1 to 3, and m11 is an integer of 0 to 2; A1 / A2 is a bond or a hydrocarbyl group; Ar1 / Ar2 is an aromatic hydrocarbyl group or the like; R1 / R4 is a hydroxy group, - X1 - or the like, is - CO-O -, - O-CO - or the like, and is a substituted / unsubstituted hydrocarbyl group; is an acid-labile group; and and are each a halogen atom, a hydrocarbyl group, or a group formed by mutually bonding and and containing X +; R3 R10 R2 R2 X1 R3 R10 L11, -CH2 - in the ring may be replaced by -O -, - S -, - SO2 -, - SO -, - CO - or the like; m1 is an integer of 1 to 5, mm1 is an integer of 2 to 5, m2 is an integer of 0 to 4, m3 and m4 are integers of 0 to 5, and mm4 is an integer of 0 or 1; and the AI - represents an organic cation. ] SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Patent Document 1 describes a salt represented by the following formula and a resist composition containing the salt as an acid generator. TIFF2026026040000001.tif2991 Patent Document 2 describes a salt represented by the following formula and a resist composition containing the salt as an acid generator. TIFF2026026040000002.tif4687 [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-164583 [Patent Document 2] Japanese Patent Application Publication No. 2023-179384 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a salt that forms a resist pattern with better line edge roughness (LER) than a resist pattern formed from a resist composition containing the above salt. [Means for solving the problem]

[0005] The present invention includes the following inventions. [1] An acid generator containing a salt represented by formula (I). TIFF2026026040000003.tif26155 [In formula (I), m10 represents an integer of 1 to 3, and when m10 is 2 or greater, the groups in the parentheses may be the same or different. m11 represents an integer of 0 to 2, and satisfies 2≦m10+m11≦3; when m10+m11=2, X represents an iodine atom; when m10+m11=3, X represents a sulfur atom; and when m11 is 2 or greater, the groups in parentheses may be the same or different. A 1 and A 2 each independently represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is -O-, -S-, -SO2-, -SO-, -NR 11 It may be replaced by - or -CO-. R 11 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ar 1 and Ar 2 each independently represents an aromatic hydrocarbon group having 6 to 10 carbon atoms or a heterocyclic hydrocarbon group having 4 to 9 carbon atoms, and the aromatic hydrocarbon group and the heterocyclic hydrocarbon group may have a substituent. R 1 and R 4 are each independently a hydroxy group, *-X 1 -R 10 or *-X 2 -L 11 -X 1 -R 10 Represents. X 1 and X 2 each independently represents -CO-O-, -O-CO-, -O-CO-O- or -O-. *Ar 1 or Ar 2 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 is not selected from -O-, -S-, -SO2-, -SO-, and -NR 11 It may be replaced by - or -CO-. R 10represents an acid labile group. R 2 and R 3 each independently represents a halogen atom or a hydrocarbon group having 1 to 28 carbon atoms, and the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is -O-, -S-, -SO2-, -SO-, -NR 11 - or -CO-, and two R 2 , two R 3 or R 2 and R 3 is bonded, and X + and -CH2- contained in the ring may be -O-, -S-, -SO2-, -SO-, -NR 11 - or -CO-, and two R 2 , two R 3 or R 2 and R 3 is X + It may also be a single bond formed between two benzene rings connecting the m1 represents an integer of 1 to 5, and when m1 is 2 or greater, the groups in the parentheses may be the same or different. mm1 represents an integer of 2 to 5, and multiple R 1 may be the same or different from each other. m2 represents an integer of 0 to 4, and satisfies 1≦m1+m2≦5. When m2 is 2 or more, a plurality of R 2 may be the same or different from each other. m3 represents an integer of 0 to 5, and when m3 is 2 or more, a plurality of R 3 may be the same or different from each other. m4 represents an integer of 0 to 5, and satisfies 0≦m3+m4≦5. When m4 is 2 or more, the groups in the parentheses may be the same or different. mm4 represents 0 or 1. AI - represents an organic cation. [2] The acid generator according to [1], wherein the cation of the salt represented by formula (I) is a cation represented by formula (IC-1). TIFF2026026040000004.tif26151[In formula (IC-1), m10, m11, X, A 1 , Ar 1 , m1, R 2 , R 3 , m2 and m3 have the same meanings as in formula (I). R 1A and R 1B are each independently a hydroxy group, *-X 1 -R 10 or *-X 2 -L 11 -X 1 -R 10 represents X 1 , X 2 , L 11 and R 10 have the same meaning as in formula (I). [3] The acid generator according to [1] or [2], wherein m10 is 1 or 2. [4] The acid generator according to [1], wherein the cation of the salt represented by formula (I) is one selected from the cations represented by formulae (IC-2) to (IC-10). TIFF2026026040000005.tif146160 [Formula (IC-2) ~ Formula (IC-10), A 1 , Ar 1 , m3, R 2 and R 3 has the same meaning as in formula (I). R 1A , R 1B and R 1C are each independently a hydroxy group, *-X 1 -R 10 or *-X 2 -L 11 -X 1 -R 10 represents X 1 , X 2 , L 11 and R 10 have the same meaning as in formula (I). X7 represents a single bond, -CH2-, -O-, -S-, -CO-, -SO-, -NR 11 - or -SO2-.] [5]A 1 But, ***-X 01 -L 01 -or***-L 01 -X 01 - and X 01 -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-, L 01 represents a single bond or a hydrocarbon group having 1 to 18 carbon atoms (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not limited to -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2- may be replaced. *** is Ar 1 The acid generator according to any one of [1] to [4], wherein the acid generator represents a bonding site with [6]X 01 is —O—, —CO—, or —S—. [7]R 1 is a hydroxy group, *-OR 10 or *-OL 11 -CO-OR 10 (* indicates Ar 1 The acid generator according to any one of [1] to [6], wherein [8]R 1 But *-X 1 -R 10 or *-X 2 -L 11 -X 1 -R 10 and R 10 The acid generator according to any one of [1] to [7], wherein the acid labile group is a group represented by formula (1a) or a group represented by formula (2a). TIFF2026026040000006.tif2156 [In formula (1a), R aa1 , R aa2 and R aa3each 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 group combining these, or R aa1 and R aa2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R aa3 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 group combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may contain a halogen atom. * denotes a binding site.] TIFF2026026040000007.tif2161[In formula (2a), R aa1’ and R aa2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa1’ represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R aa2’ and R aa3’ are bonded to each other and they combine -CX a Together with -, they form 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 a represents an oxygen atom or a sulfur atom. * denotes a binding site.] [9] The acid generator according to any one of [1] to [8], wherein X is a sulfur atom.

[10] Ar 1 is a group derived from a benzene ring, a naphthalene ring, a furan ring, or a thiophene ring.

[11] AI - is a sulfonate anion, a sulfonylimide anion, or a sulfonylmethide anion.

[12] AI- is a sulfonate anion, and the sulfonate anion is an anion represented by formula (IA). TIFF2026026040000008.tif1587[In formula (IA), 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-, -SO- or -SO2-. L b2 represents 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-, -SO- or -SO2-. Y b1 represents an optionally substituted methyl group or an optionally substituted cyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. 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.]

[13] An acid generator according to any one of [1] to

[12] ; The resist composition further comprises a salt that generates an acid that is weaker in acidity than the acid generated from the salt represented by formula (I).

[14] The resist composition according to

[13] , wherein the solid content of the resist composition comprises a salt represented by formula (I) and a salt that generates an acid that is weaker in acidity than the acid generated from the salt represented by formula (I).

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

[12] and a compound having a structure represented by formula (L0). TIFF2026026040000009.tif2471[In formula (L0), Ar lk represents an aromatic hydrocarbon ring having 6 to 18 carbon atoms which may have a substituent. X lk represents a single bond or a carbonyl group. R lk represents a hydrogen atom or an acid labile group. lk represents an integer of 1 or more, and when lk is 2 or more, the groups in the parentheses may be the same or different. * denotes a binding site. lo represents an integer greater than or equal to 1.]

[16] The resist composition according to

[15] , wherein the compound having a structure represented by formula (L0) is a compound represented by formula (LX): TIFF2026026040000010.tif24131[In formula (LX), Ar k1 and Ar k2 each independently represents an aromatic hydrocarbon ring having 6 to 18 carbon atoms. X lk1 and X lk2 each independently represents a single bond or a carbonyl group. R lk1 and R lk2 each independently represents a hydrogen atom or an acid labile group. Lx represents a hydrocarbon group having 1 to 80 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -CO-, -S-, -SO-, and -NR 11 It may be replaced by - or -SO2-. R lk11 and R lk22 each independently represents a hydrocarbon group having 1 to 20 carbon atoms which may have a halogen atom or a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -CO-, -S-, -SO-, and -NR 11 - or -SO2-. lk11 and R lk22 , R lk11 and Lx or R lk22 and Lx may be bonded to each other to form a ring, and the ring may have a substituent. -CH2- contained in the ring may be -O-, -S-, -CO-, -SO-, -NR 11 It may be replaced by - or -SO2-. lx2 represents an integer of 1 to 6, and when lx2 is 2 or greater, the groups in the parentheses may be the same or different. lk1' represents an integer of 1 to 13, and when lk1' is 2 or greater, the groups in the parentheses may be the same or different. lk11' represents an integer of 0 to 12, and when lk11' is 2 or greater, the groups in the parentheses may be the same or different. lk2' represents an integer of 1 to 13, and when lk2' is 2 or greater, the groups in the parentheses may be the same or different. lk22' represents an integer of 0 to 12, and when lk22' is 2 or greater, the groups in the parentheses may be the same or different.]

[17] The resist composition according to

[15] or

[16] , wherein the compound having a structure represented by formula (L0) is a resin containing a structural unit represented by formula (a2-A). TIFF2026026040000011.tif29127[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 -CH2- contained in the alkanediyl group is -O-, -CO- or -NR a28 - 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 a carbonyl group. nA2 represents an integer of 1 to 5, and when nA2 is 2 or greater, the groups in the parentheses may be the same or different. na21 represents an integer of 0 to 4, and when na21 is 2 or more, a plurality of R a27 may be the same or different from each other. mc represents an integer between 0 and 2.

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

[13] to

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

[19] A salt represented by the above formula (I). [Effects of the Invention]

[0006] By using a resist composition containing the salt of the present invention, a resist pattern with good line edge roughness (LER) can be produced. DETAILED DESCRIPTION OF THE INVENTION

[0007] In this specification, "(meth)acrylic monomer" means "at least one of an acrylic monomer and a methacrylic monomer." The terms "(meth)acrylate" and "(meth)acrylic acid" have the same meaning. In the groups described in this specification, those that can have both a linear structure and a branched structure may have either. When -CH2- contained in a hydrocarbon group or the like is -O-, -S-, -CO-, -SO-, -NR XWhen replaced with - (X is any symbol) or -SO2-, the same examples apply to each group, and the number of carbon atoms before replacement is the number of carbon atoms in the hydrocarbon group, etc. "Combined group" refers to a group formed by combining two or more of the exemplified groups, and the valence of these groups may vary appropriately depending on the bonding form. "Derived from" or "derived from" refers to the polymerizable C=C bond contained in the molecule becoming a -CC- group (single bond) through polymerization. If stereoisomers exist, all stereoisomers are included. Depending on the number of substituents, etc., any position and number of hydrogen atoms contained in each group may be substituted for the bonding site. The number of carbon atoms in the substituent is not included in the number of carbon atoms in the substituted group. "Acid labile group" refers to a group that, upon contact with acid (e.g., trifluoromethanesulfonic acid, etc.), eliminates the leaving group to form a hydrophilic group (e.g., a hydroxy group or a carboxy group, etc.). The term "base labile group" refers to a group that, when contacted with a base (e.g., trimethylamine, tetramethylammonium hydroxide, etc.), eliminates the leaving group to form a hydrophilic group (e.g., a carboxy group or a hydroxy group, etc.). In this specification, the term "solid content of the resist composition" refers to the sum of all components in the resist composition excluding the solvent (E), which will be described later.

[0008] [Salt represented by formula (I)] The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as "salt (I)"). In the salt (I), the negatively charged side is sometimes called the "anion (I)" and the positively charged side is sometimes called the "cation (I)".

[0009] [Cation (I)] The cation (I) of the salt represented by formula (I) is a cation represented by formula (IC). TIFF2026026040000012.tif26149 [In formula (IC), all symbols have the same meaning as in formula (I)]

[0010] In formula (I), R 1 and R 4 X included in 1is preferably *-CO-O-, *-O- or *-O-CO-O-, more preferably *-CO-O- or *-O- (where * is 1 Or L 11 or Ar 2 Or L 11 represents the binding site with ). R 1 and R 4 X included in 2 is preferably *-CO-O-, *-O-CO- or *-O-, more preferably *-CO-O- or *-O- (* is Ar 1 or Ar 2 represents the binding site with ). R 1 and R 4 L included in 11 Examples of the hydrocarbon group in include linear or branched chain hydrocarbon groups such as alkanediyl groups, monocyclic or polycyclic (including spiro rings, fused rings, or bridged rings) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may also be groups combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and an alkanediyl group). Chain hydrocarbon groups and alicyclic hydrocarbon groups are also referred to as aliphatic hydrocarbon groups, and alicyclic hydrocarbon groups and aromatic hydrocarbon groups are also referred to as cyclic hydrocarbon groups. The hydrocarbon group preferably has 1 to 24 carbon atoms, more preferably 1 to 20, and even more preferably 1 to 18 carbon atoms. 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, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, and heptadecane-1,17-diyl groups; 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. 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 10, still more preferably 1 to 9, even more preferably 1 to 8, 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 can be any position. TIFF2026026040000013.tif42165Specifically, 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 such divalent alicyclic hydrocarbon groups include cycloalkyl groups such as norbornane-1,4-diyl, norbornane-2,5-diyl, adamantane-1,5-diyl, adamantane-2,6-diyl, spirocyclohexane-1,2'-cyclopentane, and spiroadamantane-2,3'-cyclopentane, and polycyclic cycloalkanediyl groups such as spiro rings each having a cycloalkyl group bonded to a norbornyl or adamantyl group via a spiro bond. The number of carbon atoms in 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 even more preferably 6 to 10 carbon atoms. Examples of groups combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group include a group combining an alicyclic hydrocarbon group with an alkanediyl group, a group combining an aromatic hydrocarbon group with an alkanediyl group, a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and an alkanediyl 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 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-, and -alkanediyl group-divalent aromatic hydrocarbon group-. 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-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-. L 11 -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms is -O-, -S-, -SO2-, -SO-, -NR 11 It may be replaced by - or -CO-. L 11The -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms is -O-, -S-, -SO2-, -SO-, -NR 11 When it is replaced with - or -CO-, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the hydrocarbon group. R 11 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, 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 11 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, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR 11 Examples of the group substituted with - or -CO- 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 thiol group (a group in which -CH2- in a methyl group is replaced with -S-), an amino group (a group in which -CH2- in a methyl group is replaced with -NR 11 -), oxy group (a group in which -CH2- in a methylene group is replaced with -O-), carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), thio group (a group in which -CH2- in a methylene group is replaced with -S-), sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), peptide group (a group in which -CH2-CH2- in an ethylene group is replaced with -CO-NR 11-), alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -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-), alkylamino group (a group in which -CH2- at any position in an alkyl group is replaced with -NR 11 -), alkyl peptide group (wherein -CH2-CH2- at any position in the alkyl group is replaced by -CO-NR 11-), 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-), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -CO-O-), alkoxycarbonyloxy group (a group in which -CH2-CH 2-CH2- is replaced by -O-CO-O-), alkoxyalkoxy group (a group in which two -CH2- at any position in an alkyl group are replaced by -O-), alkoxyalkyl group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), hydroxyalkyl group (a group in which -CH2- in a methyl group at any position in an alkyl group is replaced by -O-), alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced by -O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -O-), an alkanediylcarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -O-CO-), an alkanediylcarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-), an alkanediylcarbonyloxy group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyloxycarbon ... alkanediylsulfonyl group (a group in which -CH- at any position in an alkanediyl group is replaced with -SO-), alkanediylthio group (a group in which -CH- at any position in an alkanediyl group is replaced with -S-), alkanediylamino group (a group in which -CH- at any position in an alkanediyl group is replaced with -NR 11 -), alkanediyl peptide group (wherein any -CH2-CH2- at any position in the alkanediyl group is replaced by -CO-NR 11-substituted), cycloalkoxy groups, cycloalkylalkoxy groups, aromatic hydrocarbon group-carbonyloxy groups, aromatic hydrocarbon group-carbonyl groups, aromatic hydrocarbon group-oxy groups, and groups combining 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, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylthio group include alkylthio groups 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, even more preferably 1 to 4, and still more preferably 1 to 3. 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, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylamino group include alkylamino groups having 1 to 27 carbon atoms, such as methylamino group, ethylamino group, dimethylamino group, propylamino group, butylamino group, pentylamino group, hexylamino group, etc. The number of carbon atoms in the alkylamino group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkyl peptide group include alkyl peptide groups having 1 to 27 carbon atoms, such as a methyl peptide group, an ethyl peptide group, a propyl peptide group, etc. The number of carbon atoms in the alkyl peptide group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 27 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 28 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 27 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 26 carbon atoms, such as a butoxycarbonyloxy group. Examples of the alkoxyalkoxy group include alkoxyalkoxy groups having 2 to 26 carbon atoms, such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, and an ethoxyethoxy group. The alkoxycarbonyl group has preferably 2 to 11 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkylcarbonyl group has preferably 2 to 12 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkylcarbonyloxy group has preferably 2 to 11 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkoxycarbonyloxy group has preferably 2 to 10 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkoxyalkoxy group has preferably 2 to 10 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. Examples of the alkoxyalkyl group include alkoxyalkyl groups having 2 to 27 carbon atoms, such as a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, and an ethoxyethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the hydroxyalkyl group include hydroxyalkyl groups having 1 to 27 carbon atoms, such as a hydroxymethyl group, a dihydroxymethyl group, a hydroxyethyl group, a dihydroxyethyl group, and a hydroxypropyl group. The number of carbon atoms in the hydroxyalkyl group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyloxy group include alkanediyloxy groups 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, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediyloxycarbonyl group include alkanediyloxycarbonyl groups having 2 to 27 carbon atoms, such as a methyleneoxycarbonyl group, an ethyleneoxycarbonyl group, a propanediyloxycarbonyl group, and a butanediyloxycarbonyl group. Examples of the alkanediylcarbonyl group include alkanediylcarbonyl groups having 2 to 28 carbon atoms, such as a methylenecarbonyl group, an ethylenecarbonyl group, a propanediylcarbonyl group, a butanediylcarbonyl group, and a pentanediylcarbonyl group. Examples of the alkanediylcarbonyloxy group include alkanediylcarbonyloxy groups having 2 to 27 carbon atoms, such as a methylenecarbonyloxy group, an ethylenecarbonyloxy group, a propanediylcarbonyloxy group, and a butanediylcarbonyloxy group. Examples of the alkanediyloxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 26 carbon atoms, such as a butoxycarbonyloxy group. The number of carbon atoms in the alkanediyloxycarbonyl 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 alkanediylcarbonyl 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 number of carbon atoms in the alkanediylcarbonyloxy 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 alkanediyloxycarbonyloxy group is preferably 2 to 10, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediylsulfonyl group include alkanediylsulfonyl groups 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, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediylthio group include alkanediylthio groups 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, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediylamino group include alkanediylamino groups having 1 to 27 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a dimethyleneamino group, a propyleneamino group, a butyleneamino group, a pentyleneamino group, a hexyleneamino group, etc. The number of carbon atoms in the alkanediylamino group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediyl peptide group include alkanediyl peptide groups having 1 to 27 carbon atoms, such as a methylene peptide group, an ethylene peptide group, a propylene peptide group, etc. The number of carbon atoms in the alkanediyl peptide group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of cycloalkoxy groups include cycloalkoxy groups having 3 to 27 carbon atoms, such as a cyclohexyloxy group. Examples of cycloalkylalkoxy groups include cycloalkylalkoxy groups having 4 to 27 carbon atoms, such as a cyclohexylmethoxy group. Examples of aromatic hydrocarbon group-carbonyloxy groups include aromatic hydrocarbon group-carbonyloxy groups having 7 to 27 carbon atoms, such as a benzoyloxy group. Examples of aromatic hydrocarbon group-carbonyl groups include aromatic hydrocarbon group-carbonyl groups having 7 to 28 carbon atoms, such as a benzoyl group. Examples of aromatic hydrocarbon group-oxy groups include aromatic hydrocarbon group-oxy groups having 6 to 27 carbon atoms, such as a phenyloxy group.

[0011] In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be replaced with -O-, -S-, -CO-, -NR 11Examples of groups substituted with -, -SO- or -SO2- include the following groups: -O- or -CO- in the groups shown below are -S- and -NR2-, respectively. 11 The binding site may be at any position. TIFF2026026040000014.tif89166

[0012] L 11 Examples of the substituent that may be possessed by L include a halogen atom, a cyano group, and a nitro group. 11 However, 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 substantially used as a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. 11 -CH2- contained in the chain hydrocarbon group such as the alkyl group contained in 11 By replacing -, -SO- or -SO2-, L 11 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 alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkylamino group, an amino group, a thiol group, an alkylthio group, an alkylsulfonyl group, or an alkylpeptide 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 hydroxy 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 The alkyl group may be a chain hydrocarbon group having 1 to 12 carbon atoms (the chain hydrocarbon group may have a substituent). The —CH— contained in the chain hydrocarbon group may be —O—, —S—, —SO—, —SO—, —NR 11- or -CO-), a cyclic hydrocarbon group having 3 to 18 carbon atoms (the cyclic hydrocarbon group may have a substituent. -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 11 - or -CO-) or a group in which a chain hydrocarbon group having 1 to 6 carbon atoms is combined with a cyclic hydrocarbon group having 3 to 18 carbon atoms (the chain hydrocarbon group and the cyclic hydrocarbon group may have a substituent. -CH2- contained in the chain hydrocarbon group and the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 11 - or -CO-), 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 1 and R 4 R included in 10 The acid labile group in R is a group that, when contacted with an acid (e.g., trifluoromethanesulfonic acid, etc.), 10 When a leaving group including a group represented by the following formula is eliminated, it forms a carboxy group or a hydroxy group. The acid labile group is preferably a group represented by formula (1a) (hereinafter sometimes referred to as "acid labile group (1a)") or a group represented by formula (2a) (hereinafter sometimes referred to as "acid labile group (2a)"). TIFF2026026040000015.tif2156 [In formula (1a), R aa1 , R aa2 and R aa3each 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 group combining these, or R aa1 and R aa2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R aa3 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 group combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may contain a halogen atom. * denotes a binding site.] TIFF2026026040000016.tif2161[In formula (2a), R aa1’ and R aa2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa1’ represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R aa2’ and R aa3’ are bonded to each other and they combine -CX a Together with -, they form 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 a represents an oxygen atom or a sulfur atom. * denotes a binding site.]

[0015] R aa1 , R aa2 and R aa3 Examples of the alkyl group of R include a methyl group, an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, and an n-octyl group. aa1 , R aa2 and R aa3The alkyl group preferably has 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 to 3 carbon atoms. R aa1 , R aa2 and R aa3 Examples of the alkenyl group include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl groups. R aa1 , R aa2 and R aa3 The alicyclic hydrocarbon group 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 (where * indicates a bonding site): aa1 , R aa2 and R aa3 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. TIFF2026026040000017.tif9159R aa1 , R aa2 and R aa3 Examples of the aromatic hydrocarbon group of R include aryl groups such as phenyl, naphthyl, anthryl, biphenyl, and phenanthryl. aa1 , R aa2 and R aa3 The aromatic hydrocarbon group preferably has 6 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms.

[0016] Examples of the combined group include a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl 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.

[0017] R aa1 and R aa2 -C(R aa1 )(R aa2 )(R aa3 ) includes the following groups. 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. * represents the bonding site with -O-. TIFF2026026040000018.tif30140

[0018] The group represented by formula (1a) is a 1,1,1-trialkyl group (R aa1 , R aa2 and R aa3 is an alkyl group, preferably a tert-butyl group), a 2-alkyladamantan-2-yl group (in formula (1a), R aa1 , R aa2 and the carbon atoms to which they are bonded form an adamantyl group, and R aa3 is an alkyl group) and 1-(adamantan-1-yl)-1,1-dialkyl groups (in formula (1a), R aa1 and R aa2 is an alkyl group, and R aa3is an adamantyl group).

[0019] R aa1' , R aa2' and R aa3' 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. The alkyl group and the alicyclic hydrocarbon group are R aa1 , R aa2 and R aa3 Examples of the groups include the same groups as those listed in the above. 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 is combined with an alicyclic hydrocarbon group (for example, a cycloalkylalkyl group or an alkylcycloalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl 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. R aa2' and R aa3' are bonded to each other and the carbon atoms to which they are bonded and X a When forming a heterocyclic group together with -C(R aa1' )(R aa2' )-X a -(R aa3' ) includes the following groups. * represents a bonding site. The heterocyclic group preferably has 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. TIFF2026026040000019.tif21144Raa1' and R aa2' At least one of these is preferably a hydrogen atom. R aa1 , R aa2 , R aa3 , R aa1’ , R aa2’ and R aa3’ The halogen atom that may be contained in the ring may be a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0020] Specific examples of the acid labile group (1a) include the following groups: * represents a bonding site. TIFF2026026040000020.tif73153

[0021] Specific examples of the acid labile group (2a) include the following groups: * represents a bonding site. TIFF2026026040000021.tif59148Ar 1 is a group derived from a benzene ring, R 1 Ar 1 The bonding positions to A are independently 1 The bonding position of A may be either o-position, m-position or p-position. 1 Preferably, at least one of the two is bonded at the p-position or m-position relative to the bonding position of Ar 1 is a group derived from a naphthalene ring, for example, A 1 When the bonding position of is the 1st position, it may be any of the 2nd to 8th positions. 1 When the bonding position of A is the 2nd position, it may be the 1st position or any of the 3rd to 8th positions. 1 When the bonding position of A is the 1st position, it is preferable that at least one of A is bonded to the 3rd to 6th positions. 1 When the bonding position of Ar is the 2nd position, it is preferable that at least one of Ar is bonded to the 4th to 7th positions. 2 is a group derived from a benzene ring or a naphthalene ring, R 4 Ar 2 The bonding position to R 1 Ar 1 The binding position is the same as that of R1 and R 4 each independently represents a hydroxy group, -OR 10 , -O-CO-OR 10 or -OL 11 -CO-OR 10 is preferably a hydroxy group, -OR 10 or -OL 11 -CO-OR 10 More preferably, -OR 10 or -OL 11 -CO-OR 10 It is more preferable that:

[0022] Ar 1 and Ar 2 Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include groups derived from a benzene ring or a naphthalene ring, such as a phenylene group or a naphthylene group. 1 and Ar 2 Examples of the heterocyclic aromatic hydrocarbon group having 4 to 9 carbon atoms include groups derived from a furan ring, a thiophene ring, a benzofuran ring, or a benzothiophene ring. Ar 1 and Ar 2 are each independently preferably a group derived from a benzene ring, a naphthalene ring, a furan ring, or a thiophene ring, and more preferably a group derived from a benzene ring.

[0023] Ar 1 and Ar 2 The substituents which the aromatic hydrocarbon group or heterocyclic hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, or a hydrocarbon group having 1 to 28 carbon atoms, and the hydrocarbon group may further have a substituent, and -CH2- contained in the hydrocarbon group is not limited to -O-, -S-, -SO2-, -SO-, -NR 11 It may be replaced by - or -CO-. Halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. Examples of the hydrocarbon group having 1 to 28 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 groups. The alkyl group is a linear 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 an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-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. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 12, more preferably 1 to 10, even more preferably 1 to 9, still more preferably 1 to 8, even more preferably 1 to 6, still 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 at any position. TIFF2026026040000022.tif42165Specific examples of monocyclic alicyclic hydrocarbon groups include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl. Examples of polycyclic alicyclic hydrocarbon groups include 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 a cycloalkyl group bonded to a norbornyl or adamantyl group via a spiro bond.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 aromatic hydrocarbon group preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms.

[0024] Examples of groups formed by combining two or more of chain hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups include groups formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group (for example, aromatic hydrocarbon group-alkanediyl group-*, alkyl group-aromatic hydrocarbon group-*, alkyl group-aromatic hydrocarbon group-alkanediyl group-*, where -CH2- contained in the alkanediyl group and the alkyl group can be -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are combined (for example, an alicyclic hydrocarbon group-alkanediyl group-*, an alkyl group-alicyclic hydrocarbon 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-, -SO-, -NR 11- or -SO2-), a group in which an aromatic hydrocarbon group and an alicyclic hydrocarbon group are combined (for example, an aromatic hydrocarbon group-alicyclic hydrocarbon group-*, an alicyclic hydrocarbon group-aromatic hydrocarbon group-*, where -CH2- contained in the alicyclic hydrocarbon group can be replaced by -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-.) * indicates a binding 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. 1 or Ar 2 may be bound to The substituents which the hydrocarbon group may have include the above-mentioned halogen atoms, cyano groups, nitro groups, etc. Examples of hydrocarbon groups having halogen atoms include chain hydrocarbon groups having halogen atoms such as haloalkyl groups, alicyclic hydrocarbon groups having halogen atoms such as halocycloalkyl groups, and aromatic hydrocarbon groups having halogen atoms. The haloalkyl group is preferably a haloalkyl group having 1 to 12 carbon atoms, and represents an alkyl group having 1 to 12 carbon atoms and a halogen atom, such as a fluorinated alkyl group having 1 to 12 carbon atoms, a chlorinated alkyl group having 1 to 12 carbon atoms, a brominated alkyl group having 1 to 12 carbon atoms, and an iodinated alkyl group having 1 to 12 carbon atoms. Examples of haloalkyl groups include perfluoroalkyl groups having 1 to 12 carbon atoms (such as a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, and a nonafluorobutyl group), a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoropropyl group, a 4,4,4-trifluorobutyl group, a 3,3,4,4,4-pentafluorobutyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The haloalkyl group preferably has 1 to 9 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and even more preferably 1 to 3 carbon atoms. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR 11 Examples of the group substituted with - or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a thiol group (a group in which -CH2- in a methyl group is replaced with -S-), an amino group (a group in which -CH2- in a methyl group is replaced with -NR 11-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -CO-O-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position in an alkyl group is replaced with , -O-CO-O-), alkoxyalkoxy group (a group in which two -CH2- at any position in an alkyl group are replaced with -O-), alkoxyalkyl group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), hydroxyalkyl group (a group in which -CH2- in a methyl group at any position in an alkyl group is replaced with -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-), alkylamino group (a group in which -CH2- at any position in an alkyl group is replaced with -NR 11 -), alkyl peptide group (wherein -CH2-CH2- at any position in the alkyl group is replaced by -CO-NR 11 -), oxy group (a group in which -CH2- in a methylene group is replaced with -O-), carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), thio group (a group in which -CH2- in a methylene group is replaced with -S-), sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), peptide group (a group in which -CH2-CH2- in an ethylene group is replaced with -CO-NR 11-), an alkanediyloxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -O-), an alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -CO- O- is replaced by), alkanediyloxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-O-), alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -S-), alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -SO2-), alkanediylamino group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -NR 11 -), alkanediyl peptide group (wherein any -CH2-CH2- at any position in the alkanediyl group is replaced by -CO-NR 11 -substituted), a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group combining two or more of these groups. 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. In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be -O-, -S-, -SO2-, -SO-, -NR 11 Examples of the group substituted with - or -CO- include the same groups as those exemplified in this specification, within the upper limit of the carbon number.

[0025] Ar 1 and Ar 2The substituents are each independently preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the haloalkyl group and the alkyl group may be replaced with -O- or -CO-), more preferably a fluorine atom, an iodine atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), and even more preferably a fluorine atom, an iodine atom, a haloalkyl 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-). O-) is more preferred, a fluorine atom, an iodine atom, a fluorinated alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, a hydroxy group, a carboxy group, or an alkoxy group having 1 to 3 carbon atoms is even more preferred, a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 3 carbon atoms, a hydroxy group, a carboxy group, or an alkoxy group having 1 to 3 carbon atoms is even more preferred, and a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, an ethyl group, a hydroxy group, a carboxy group, a methoxy group, or an ethoxy group is even more preferred. Ar 1 The bonding position of the substituent in Ar 1 are groups derived from a benzene ring, each independently 1 In particular, when there is one substituent, each of the substituents independently may be one of the following: A 1 When there are two substituents, each of the substituents is preferably bonded to the p-position or m-position relative to the bonding position of A. 1 It is preferred that one is bonded to the o-position or m-position and the other is bonded to the p-position or m-position with respect to the bonding positions of A. 1 Preferably, two of them are bonded to the o- or m-position, and one is bonded to the p- or m-position with respect to the bonding positions of Ar 1 is a group derived from a naphthalene ring, for example, A 1When the bonding position of is the 1st position, it may be any of the 2nd to 8th positions. 1 When the bonding position of A is the 2nd position, it may be the 1st position or any of the 3rd to 8th positions. 1 When the bonding position of A is the 1st position, it is preferable that at least one of A is bonded to the 3rd to 6th positions. 1 , A 2 and A 3 When the bonding position of Ar is the 2nd position, it is preferable that at least one of Ar is bonded to the 4th to 7th positions. 2 The bonding position of the substituent in Ar 1 The bonding positions of the substituents are the same as those in

[0026] A 1 and A 2 Examples of the hydrocarbon group include linear or branched chain hydrocarbon groups (e.g., alkanediyl groups, etc.), monocyclic or polycyclic alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may be a combination of two or more of these groups. The number of carbon atoms in the hydrocarbon group is preferably 1 to 19, more preferably 1 to 18, even more preferably 1 to 16, still more preferably 1 to 14, and even more preferably 1 to 12. Examples of the chain hydrocarbon group include straight-chain alkanediyl groups such as methylene, ethylene, propane-1,3-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, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, and heptadecane-1,17-diyl; Examples of branched alkanediyl groups include an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-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. 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, still more preferably 1 to 6, even more preferably 1 to 4, and still 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 at any position. TIFF2026026040000023.tif42165Specifically, monocyclic alicyclic 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; Examples include polycyclic alicyclic hydrocarbon groups such as polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl, norbornane-2,5-diyl, adamantane-1,5-diyl, and adamantane-2,6-diyl; cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane and spiroadamantane-2,3'-cyclopentane; and spiro rings having a cycloalkyl group bonded to a norbornyl group or an adamantyl group via a spiro bond. The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, even more preferably 3 to 12 carbon atoms, and even more preferably 3 to 10 carbon atoms. 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 preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms.

[0027] Examples of groups formed by combining groups include a group formed by combining an alicyclic hydrocarbon group with an alkanediyl group, a group formed by combining an aromatic hydrocarbon group with an alkanediyl group, and a group formed by combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group. In the combination, two or more chain hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups may be combined. Furthermore, any of the groups may be bonded to a benzene ring. 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-, and -alkanediyl group-divalent aromatic hydrocarbon group-. 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-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-.

[0028] A 1 and A 2 In this case, -CH2- contained in the hydrocarbon group can be -O-, -CO-, -S-, -SO-, -NR 11 When the hydrocarbon group is substituted with - or -SO2-, the number of carbon atoms before the substitution is taken as the total number of carbon atoms in the hydrocarbon group. The number may be one or more, but is preferably one or two. The -CH2- contained in the hydrocarbon group can be -O-, -CO-, -S-, -SO-, or -NR 11Examples of the group substituted for - or -SO2- include a hydroxy group, a carboxy group, a thiol group, an amino group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, a peptide group, an alkoxy group, an alkylthio group, an alkylsulfonyl group, an alkylamino group, an alkylpeptide group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkoxyalkyl group, a hydroxyalkyl group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediyloxycarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, an alkanediylamino group, an alkanediylpeptide group, a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group formed by combining two or more of these groups. These substituted groups include the same groups as those exemplified in this specification, within the limits permitted by the upper limit of the number of carbon atoms.

[0029] In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be -O-, -CO-, -S-, -SO-, -NR 11 The group substituted with - or -SO2- includes the same groups as those exemplified in this specification, within the upper limit of the carbon number. A 1 and A 2 The hydrocarbon group may have a substituent such as Ar 1 and Ar 2 Examples of the substituent include the same groups as those exemplified as the substituents that the aromatic hydrocarbon group or heterocyclic aromatic hydrocarbon group may have. A 1 and A 2 each independently represents a hydrocarbon group having 1 to 20 carbon atoms (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not limited to -O-, -CO-, -S-, -SO-, -NR 11- or -SO2-, provided that at least one of -CH2- contained in the hydrocarbon group is not -O-, -CO-, -S-, -SO-, or -NR2-. 11 - or -SO2- is preferably used. 1 is **-L 011 -X 01 -L 012 -is (X 01 -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-. 011 and L 012 each independently represents a single bond or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2- may be replaced. 011 and L 012 The total number of carbon atoms is 0 to 18. ** indicates Ar 1 It is more preferable that A 1 is **-X 01 -L 01 -or**-L 01 -X 01 -is (X 01 each independently represents -O-, -CO-, -S-, -SO-, or -NR 11 - or -SO2-. 01 represents a single bond or a hydrocarbon group having 1 to 18 carbon atoms, and the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not -O-, -CO-, -S-, -SO-, or -NR 11 - or -SO2- may be replaced. ** indicates Ar 1 It is more preferable that A 1 -O-, -CO-, -S-, -SO-, -NR 11 Those having no substituents other than the - or -SO2- substitution are also preferred. L 011 , L 012 and L 01a hydrocarbon group having 1 to 18 carbon atoms (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not limited to -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-) has a carbon number of 1 to 18, and A 1 Examples of the groups include the same groups as those listed in the above. X 01 each independently represents -O-, -CO-, -S-, or -NR 11 - or -SO2- is preferred, and -O-, -CO-, -S- or -NR 11 It is more preferably -, further preferably -O-, -CO- or -S-, and even more preferably -O- or -CO-. L 011 , L 012 and L 01 are each independently a single bond or a hydrocarbon group having 1 to 18 carbon atoms (-CH2- contained in the hydrocarbon group is not limited to -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-), and a single bond or a hydrocarbon group having 1 to 12 carbon atoms (the -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-) is more preferred, and the —CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by a single bond, a chain hydrocarbon group having 1 to 9 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or a group in which a chain hydrocarbon group having 1 to 4 carbon atoms and an alicyclic hydrocarbon group having 3 to 10 carbon atoms are combined (the —CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by —O—, —CO—, —S—, —SO—, —NR 11- or -SO2-), even more preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (wherein -CH2- in the alkanediyl group may be replaced by -O- or -CO-), even more preferably a single bond or an alkanediyl group having 1 to 4 carbon atoms (wherein -CH2- 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 3 carbon atoms (wherein -CH2- in the alkanediyl group may be replaced by -O- or -CO-). Among these, a single bond, a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, an oxy group, a carbonyl group, a carbonyloxy group, a carbonyloxymethylene group, an ethyleneoxy group, an ethyleneoxymethylene group, a methylenecarbonyloxy group, a methylenecarbonyloxymethylene group, or an ethyleneoxycarbonyl group is preferred, and a single bond, a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, an oxy group, or a carbonyl group is more preferred. 011 and L 012 The total number of carbon atoms is 0 to 18. A 2 Regarding A 1 Groups similar to the following are preferred. Also, A 1 and A 2 each independently represents a single bond, a chain hydrocarbon group having 1 to 20 carbon atoms, a cyclic hydrocarbon group having 3 to 20 carbon atoms, or a hydrocarbon group having 4 to 20 carbon atoms, which is a combination thereof (provided that the chain hydrocarbon group and the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the chain hydrocarbon group and the cyclic hydrocarbon group is not -O-, -S-, -SO2-, -SO-, -NR 11In this case, a single bond, a chain hydrocarbon group having 1 to 18 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a hydrocarbon group having 4 to 18 carbon atoms by combining these (however, the chain hydrocarbon group and the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the chain hydrocarbon group and the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 11 - or -CO- may be substituted.) is more preferred. A 1 and A 2 X + The bonding positions of X to the benzene ring are each independently + The bonding position of X may be either o-position, m-position or p-position. + More specifically, when m1 is 1, A 1 are each independently, X + It is preferably bonded to the p-position or m-position, more preferably to the p-position, relative to the bonding position of A. 1 are each independently, X + With respect to the bonding positions of A, it is preferable that one is bonded to the o-position or the m-position, and one is bonded to the o-position or the m-position, and it is more preferable that two are bonded to the m-position. 1 are each independently, X + With respect to the bonding positions of A, it is preferred that two are bonded to the o- or m-position and one is bonded to the p- or m-position, and it is more preferred that two are bonded to the m-position and one is bonded to the p-position. 1 are each independently, X + With respect to the bonding positions of A, it is preferred that two are bonded to the o-position or m-position, and two are bonded to the p-position or m-position, and it is more preferred that two are bonded to the o-position and two are bonded to the m-position. 2 X + The bond position to the benzene ring to which A is attached is also 1 X + The bond position to the benzene ring is the same as that to which the mm1 is preferably 2, 3 or 4, more preferably 2 or 3, and even more preferably 2. m1 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. m2 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. m3 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. m4 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, even more preferably 0 or 1, and even more preferably 0.

[0030] R 2 and R 3 The halogen atoms are Ar 1 Examples of the halogen atoms include the same halogen atoms as those exemplified as the substituents that may be possessed by the group. R 2 and R 3 a hydrocarbon group having 1 to 28 carbon atoms (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not limited to -O-, -S-, -SO2-, -SO-, -NR 11 - or -CO- may be replaced by L 11 or Ar 1 The hydrocarbon groups listed as the substituents that may be possessed by the hydrocarbon group (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not limited to -O-, -S-, -SO2-, -SO-, -NR 11 - or -CO- may be substituted.) R 2 and R 3 The hydrocarbon group may be a group having an acid labile group at the end, and for example, within the range permitted by the upper limit of the number of carbon atoms, R 1 *-X shown in the example 1 -R10 and *-X 2 -L 11 -X 1 -R 10 or *-A 1 -Ar 1 -X 1 -R 10 and *-A 1 -Ar 1 -X 2 -L 11 -X 1 -R 10 (* indicates R 2 or R 3 This should be read as the bonding site between the benzene ring and the bonded group. R 2 and R 3 each independently represents a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the haloalkyl group and the alkyl group may be replaced by -O- or -CO-), -OR 10 , -O-CO-OR 10 or -OL 11 -CO-OR 10 and a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms (wherein —CH2— contained in the alkyl group may be replaced by —O— or —CO—), —OR 10 , -O-CO-OR 10 or -OL 11 -CO-OR 10 and more preferably a fluorine atom, an iodine atom, a fluorinated alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms (wherein —CH2— contained in the alkyl group may be replaced by —O— or —CO—), —OR 10 , -O-CO-OR 10 or -OL 11 -CO-OR 10 It is more preferable that the group is a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, a hydroxy group, a carboxy group, an alkoxy group having 1 to 3 carbon atoms, -OR 10 , -O-CO-OR 10 or -OL11 -CO-OR 10 It is more preferable that the alkyl group is a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, an ethyl group, a t-butyl group, a hydroxy group, a carboxy group, a methoxy group, an ethoxy group, or -OR 10 , -O-CO-OR 10 or -OL 11 -CO-OR 10 It is even more preferred that: R 2 and R 3 The bonding positions of X to the benzene ring are each independently + The bonding position of R may be either o-position, m-position, or p-position. 2 are each independently, X + Preferably, the bond is p- or m-position relative to the bonding position of R, more preferably p-position. 2 are each independently, X + With respect to the bonding positions of R, it is preferred that one is bonded to the o- or m-position and one is bonded to the p- or m-position, and it is more preferred that one is bonded to the m-position and one is bonded to the p- or m-position. 2 are each independently, X + With respect to the bonding positions of R, it is preferred that two are bonded to the o- or m-position and one is bonded to the p- or m-position, and it is more preferred that two are bonded to the m-position and one is bonded to the p-position. 2 are each independently, X + With respect to the bonding positions of R, it is preferred that two are bonded to the o- or m-position and two are bonded to the p- or m-position, and it is more preferred that two are bonded to the m-position, one is bonded to the o-position, and one is bonded to the p-position. 3 The bonding position of R to the benzene ring is also 2 The bonding position to the benzene ring is the same as that of

[0031] The Two R's 2 , two R 3 or R 2 and R 3 is bonded, and X+ When forming a ring containing: X is preferably a sulfur atom, and for example, it is preferably a cation represented by the following formula (IC'). TIFF2026026040000024.tif51153[In formula (I-C'), R 1A , R 1B and R 1C are each independently represented by the formula (I), R 1 It has the same meaning as: R 2A , R 2B and R 2C are each independently represented by the formula (I), R 2 It has the same meaning as: A 1A , A 1B and A 1C are each independently a group represented by the formula (I), A 1 It has the same meaning as: Ar 1A , Ar 1B and Ar 1C are each independently represented by the formula (I), Ar 1 It has the same meaning as: mm1A, mm1B and mm1C each independently represent an integer of 1 to 5, and any one of mm1A, mm1B and mm1C represents an integer of 2 or more. m1A represents an integer of 0 to 5, and when m1A is 2 or more, the groups in the parentheses may be the same or different. m2A represents an integer of 0 to 5, and satisfies 0≦m1A+m2A≦5, and when m2A is 2 or more, the groups in the parentheses may be the same or different. m1B and m1C each independently represent an integer of 0 to 4, and when m1B and m1C each represent 2 or more, the groups in the respective parentheses may be the same or different. m2B and m2C each independently represent an integer of 0 to 4, satisfying 0≦m1B+m2B≦4 and 0≦m1C+m2C≦4, respectively, and when m2B and m2C are each 2 or more, the groups in each of the multiple parentheses may be the same or different. Any one of m1A, m1B, and m1C represents an integer of 1 or more. X 7 represents a single bond, -CH2-, -O-, -S-, -CO-, -SO-, -NR 11 - or -SO2-.] X 7 is preferably a single bond, —CH 2 — or —O—.

[0032] The cation represented by formula (IC) is preferably a cation represented by formula (IC-1). TIFF2026026040000025.tif26151[In formula (IC-1), m10, m11, X, A 1 , Ar 1 , m1, R 2 , R 3 , m2 and m3 have the same meanings as in formula (I). R 1A and R 1B are each independently a hydroxy group, *-X 1 -R 10 or *-X 2 -L 11 -X 1 -R 10 represents X 1 , X 2 , L 11 and R 10 have the same meaning as in formula (I). Furthermore, the cation represented by formula (IC) is preferably a cation represented by the following formulas (IC-2) to (IC-10). TIFF2026026040000026.tif146160 [Formula (IC-2) ~ Formula (IC-10), A 1 , Ar 1 , m3, R 2 and R 3 has the same meaning as in formula (I). R 1A , R 1B and R 1C are each independently a hydroxy group, *-X 1 -R 10 or *-X2 -L 11 -X 1 -R 10 represents X 1 and X 2 and L 11 and R 10 each represent the same meaning as formula (I). X 7 represents the same meaning as formula (I-C’). In formulas (I-C-2) to (I-C-10), the subscript numbers near the outside of each parenthesis represent valences, and "P1 - P2 (where P1 and P2 are both integers and P1 < P2)" means "represents any integer from P1 to P2". For example, in formula (I-C-2), the "0 - 2" in (R 2 ) 0-2 represents "any integer from 0 to 2", and in formulas (I-C-2) to (I-C-10), the subscript numbers near the outside of other parentheses have the same meaning.

[0033] [[ID=二十九]]Examples of the cation of salt (I) include cations represented by the following formulas (I-c-1) to (I-c-105). TIFF2026026040000027.tif244162

[0034] TIFF2026026040000028.tif243155

[0035] TIFF2026026040000029.tif250150

[0036] TIFF2026026040000030.tif238106

[0037] TIFF2026026040000031.tif248162

[0038] TIFF2026026040000032.tif222138

[0039] TIFF2026026040000033.tif240162

[0040] TIFF2026026040000034.tif253160

[0041] TIFF2026026040000035.tif120111

[0042] [Anion (I)] AI - Examples of the organic anion represented by the formula (I) include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion. The sulfonate anion includes an anion represented by formula (IA). TIFF2026026040000036.tif1389 [In formula (IA), all symbols have the same meanings as defined above.] In formula (IA), 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 combines 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 following: The hydrocarbon group preferably has 1 to 48 carbon atoms, more preferably 1 to 42 carbon atoms, even more preferably 1 to 36 carbon atoms, even more preferably 1 to 30 carbon atoms, and even more preferably 1 to 24 carbon atoms. L b1Examples of the chain hydrocarbon group include groups in which nb hydrogen atoms have been removed from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentanedecyl, and heptadecyl. Examples of the alkenyl group include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl. L b1 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. L b1Examples of the alicyclic hydrocarbon group include groups in which nb hydrogen atoms have been removed from a monocyclic or polycyclic cycloalkyl group. Examples of monocyclic cycloalkyl groups include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of polycyclic cycloalkyl groups include a cycloalkyl group having a bridged structure, a cycloalkyl group in which two or more rings are fused, or a cycloalkyl group in which two rings are bonded via 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 fused include a bicyclo[4.4.0]decanyl group and a steroid group (steroid skeleton). Examples of cycloalkyl groups in which two rings are bonded via 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 via a spiro bond to a cycloalkyl group having 5 to 8 carbon atoms. In addition, 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. TIFF2026026040000037.tif40166L b1 When 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, still more preferably 3 to 12, even more preferably 3 to 10, and still 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, still more preferably 6 to 12, and even more preferably 7 to 12. L b1 Examples of the aromatic hydrocarbon group include groups in which nb1 hydrogen atoms have 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. More specifically, aromatic hydrocarbon groups represented by the following formulas are included. TIFF2026026040000038.tif1186The 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, still more preferably 5 to 14, even more preferably 5 to 10, and even more preferably 6 to 10. Examples of the group combining two or more groups selected from the group consisting of a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group include a group combining the above-mentioned chain hydrocarbon group with the above-mentioned alicyclic hydrocarbon group, a group combining the above-mentioned chain hydrocarbon group with the above-mentioned aromatic hydrocarbon group, a group combining the above-mentioned alicyclic hydrocarbon group with the above-mentioned aromatic hydrocarbon group, and a group combining the above-mentioned chain hydrocarbon group with the above-mentioned alicyclic hydrocarbon group and the above-mentioned aromatic hydrocarbon group. The group combining the alicyclic hydrocarbon group with the aromatic hydrocarbon group may be a fused ring. b1 When -CH2- in the hydrocarbon group is replaced with -O-, -CO-, -S-, -SO- or -SO2-, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the hydrocarbon group. L b1Among the hydrocarbon groups mentioned above, examples of groups in which -CH2- in a chain hydrocarbon group is replaced with -O-, -CO-, -S-, -SO- or -SO2- include a hydroxy group, a carboxy group, a thiol group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkoxy group, an alkylthio group, an alkylsulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediyloxycarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and groups in which two or more of these groups are combined. These substituted groups include the same groups as those exemplified in this specification, within the limits permitted by the upper limit of the number of carbon atoms. L b1 Among the hydrocarbon groups, examples of groups in which -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these is replaced with -O-, -CO-, -S-, -SO-, or -SO2- include groups containing structures such as cyclic ether, cyclic ketone, cyclic ester (lactone), cyclic thioether, cyclic acetal, and cyclic sulfonate ester (sultone), as well as groups derived from a furan ring or a thiophene ring. Specific examples include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. b2 Examples of the divalent hydrocarbon group include a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group combining two or more of these groups. A monovalent hydrocarbon group can be obtained by removing one hydrogen atom to form Y b1 Examples of such groups include groups that bond to the following: L b2 The divalent chain hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group formed by combining 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 and removing one hydrogen atom from them. 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, etc. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. L b1 and L b2 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. b1 and L b2 The -CH2- of the chain hydrocarbon group contained in the hydrocarbon group is replaced by -O-, -CO-, -S-, -SO- 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 alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, a thiol group, an alkylthio group, or an alkylsulfonyl 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, respectively, L b1 Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups include those similar to those exemplified in 1., and when they have no substituent, they may be monovalent alicyclic hydrocarbon groups and aromatic hydrocarbon groups. Y b1Examples of the substituent that the methyl group and cyclic hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, or 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 with -O-, -S-, -CO-, -SO-, or -SO2-). b1 The number of carbon atoms in the hydrocarbon group that the methyl group or cyclic hydrocarbon group may have is b1 The carbon number of the methyl group or the hydrocarbon group of the cyclic hydrocarbon group is not included in the carbon number of the methyl group or the cyclic hydrocarbon group. Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that may be substituted on the methyl group and 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 number of carbon atoms, L b1 Examples of the hydrocarbon groups include the chain hydrocarbon groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups in which two or more of these groups are combined, as exemplified above. Also, Y b1 Examples of the methyl group and the hydrocarbon group having 1 to 18 carbon atoms that may have a substituent, in which -CH2- is replaced by -O-, -S-, -CO-, -SO- or -SO2-, are, within the range permitted by the upper limit of the number of carbon atoms, L 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-, -SO- or -SO2-. b1 The hydrocarbon group having 1 to 18 carbon atoms that the methyl group and cyclic hydrocarbon group may have as a substituent may constitute a protecting group or leaving group (acid labile group or base labile group) commonly used in the art. The anion represented by formula (IA) is preferably an anion represented by the following formula (I-A1) (hereinafter, sometimes referred to as "anion (I-A1)") or an anion represented by formula (I-A2) (hereinafter, sometimes referred to as "anion (I-A2)"). TIFF2026026040000039.tif29126[In formula (I-A1), L b2 and Y b1 has the same meaning as in formula (IA). 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, multiple Q b3 and multiple Qs b4 may be the same or different from each other. X 1 represents -O-CO-, -CO-O-, -O-CO-O- or -O-. L b3 represents a single bond or an (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-, -SO- or -SO2-. nb2 represents an integer of 1 to 3. When nb2 is 2 or more, a plurality of -L b2 -Y b1 may be the same or different from each other. Q b1 , Q b2 , Q b3 and Q b4 Examples of the alkyl group having 1 to 6 carbon atoms 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 , Q b2 , Q b3 and Q b4 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms 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 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—. L b3 As the hydrocarbon group in the formula (IA), within the range permitted by the upper limit of the number of carbon atoms, b1 Examples of the hydrocarbon groups include the same groups as those exemplified above. In formula (I-A1), L b3is preferably a single bond, an optionally substituted chain hydrocarbon group of 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), an optionally substituted alicyclic hydrocarbon group of 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO-, -SO- or -SO2-), an optionally substituted aromatic hydrocarbon group of 6 to 10 carbon atoms (-CH2- contained in the aromatic hydrocarbon group may be replaced with -O- or -S-), or a group comprising a combination of two or more of these groups, and more preferably a single bond, an optionally substituted chain hydrocarbon group of 1 to 6 carbon atoms, or a group represented by the following formula (Lb3-1): When -CH2- in the chain hydrocarbon group is replaced with -O- or -CO-, the number of -CH2- in the chain hydrocarbon group replaced with -O- or -CO- is preferably 1 to 4, and it is preferred that one -CH2-CH2- in the chain hydrocarbon group is replaced with -O-CO- or -CO-O-, or one -CH2-CH2-CH2- in the chain hydrocarbon group is replaced with -O-CO-O-. TIFF2026026040000040.tif1580[In formula (Lb3-1), nb2 has the same meaning as in formula (I-A1). L b31 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms, and -CH2- contained in the chain hydrocarbon group may be replaced with -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, wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-, and -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 with In formula (Lb3-1), L b31The chain hydrocarbon group is, as far as the upper limit of the carbon number allows, L of formula (IA). b1 Examples of the chain hydrocarbon groups include the same groups as those exemplified above. In formula (Lb3-1), W b3 The alicyclic hydrocarbon group and aromatic hydrocarbon group of formula (IA) are, as far as the upper limit of the number of carbon atoms allows, b1 Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups are the same as those exemplified above. In formula (Lb3-1), L b31 The substituents that the chain hydrocarbon group of W may have and b3 The substituents that the alicyclic hydrocarbon group and aromatic hydrocarbon group may have are as follows: b1 Examples of the substituent that the hydrocarbon group may have include the same groups as the substituents 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 The alicyclic hydrocarbon group and aromatic hydrocarbon group are preferably the alicyclic hydrocarbon group and aromatic hydrocarbon group shown below. In the alicyclic hydrocarbon group and aromatic hydrocarbon group shown below, * represents X 1 or L b31 represents a bonding site with L, and ** represents a hydrogen atom, a substituent, or L b2 represents a binding site with at least one ** b2 represents a bonding site with. In the alicyclic hydrocarbon groups represented below, -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO-, -SO-, or -SO2-. When -CH2- contained in the alicyclic hydrocarbon group is replaced with -O-, -S-, -CO-, -SO-, or -SO2-, the alicyclic hydrocarbon group preferably forms an ether ring, an ester ring (lactone), a carbonate ester ring, a sulfonate ester ring (sultone), or an acetal ring. In TIFF2026026040000041.tif37165 formula (I-A1), 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 at least 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 represents the binding site with L b21 , X 2 and L b22 The total number of carbon atoms is 12 or less. In formula (I-A1), Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S-, -SO-, or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S-, -SO-, 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- in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S-, -SO-, or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, groups represented by the following formulae (Y1) to (Y36) are preferred. In formulas (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 of the formula (I) may have, and * represents a substituent that the cyclic hydrocarbon group of the formula (I) may have, b2The alicyclic hydrocarbon groups and aromatic hydrocarbon groups represented by the following formulae (Y1) to (Y36) may have other substituents, although these are not specifically shown in the following formulae. TIFF2026026040000042.tif84158The anion represented by formula (I-A1) is preferably an anion represented by formula (IA-1) to formula (IA-85) (hereinafter, sometimes referred to as "anion (IA-1)" or the like depending on the formula number), and more preferably an anion represented by any of formulas (IA-1) to (IA-4), (IA-9), (IA-10), (IA-24) to (IA-33), (IA-36) to (IA-40), and (IA-47) to (IA-85). TIFF2026026040000043.tif216162

[0043] TIFF2026026040000044.tif254157

[0044] TIFF2026026040000045.tif254164 Here 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 is, for example, an aliphatic 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 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 has the same meaning as above. Specific examples of the anion represented by formula (I-A1) include the anions described in JP-A-2010-204646. The anion represented by formula (I-A1) is preferably an anion represented by formulas (Ia-1) to (Ia-72), respectively. Among these, an anion represented by any one of formulas (Ia-1) to (Ia-4), (Ia-7) to (Ia-11), (Ia-14) to (Ia-30), and (Ia-35) to (Ia-70) is preferred. TIFF2026026040000046.tif181164

[0045] TIFF2026026040000047.tif254165

[0046] TIFF2026026040000048.tif93165

[0047] (Anion (I-A2)) The anion represented by formula (I-A2) is represented by the following formula: TIFF2026026040000049.tif2495[In formula (I-A2), L b2 and Y b1 has the same meaning as in formula (IA). R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and one --CH.sub.2-- 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 greater, the groups in the 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. In formula (I-A2), L b2 and Y b1 As the cyclic hydrocarbon group, within the range permitted by the upper limit of the number of carbon atoms, L of formula (IA) b2 and Y b1 Examples of the cyclic hydrocarbon group include the same groups as those listed in L b2hydrocarbon group, Y b1 The substituents that the methyl group and the cyclic hydrocarbon group may have are also defined as follows: b2 hydrocarbon group, Y b1 Examples of the substituents that the methyl group and cyclic hydrocarbon group may have include the same groups as those mentioned above. These hydrocarbon groups, methyl groups and cyclic hydrocarbon groups may have one or more substituents. 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 - 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-, -SO- 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-, -SO- or -SO2-), or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and even more preferably Y in formula (I-A1) b1 or L b1 Specifically, the groups represented by the above formulae (Y1) to (Y36) are preferred, and the groups represented by the above formulae (Y1) to (Y19) are more preferred. Y b1The substituents that the cyclic hydrocarbon group may have are preferably a halogen atom or an alkyl group having 1 to 6 carbon atoms (wherein -CH2- in the alkyl group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-), more preferably a fluorine atom, an iodine atom or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- in the alkyl group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-), even more preferably a fluorine atom, an iodine atom, a hydroxy group, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 4 carbon atoms, and even more preferably a fluorine atom, an iodine atom, a hydroxy group or an alkyl group having 1 to 4 carbon atoms. b1 The substituent of may constitute a protecting group or leaving group (acid labile group or base labile group) commonly used in the art. In formula (I-A2), nb4 is preferably an integer of 1 to 4, more preferably an integer of 1 to 3, further preferably 1 or 2, and even more preferably 2. When nb4 is 1 or 2, -L b2 -Y b1 The bond position of SO3 - Preferably, the following structure is substituted at the meta position of the benzene ring relative to the bonding position of the above. TIFF2026026040000050.tif29108 [In the above formula, L b2 , Y b1 , R b1 , nb3 has the same meaning as in formula (I-A2). In formula (I-A2), when nb4 is 2 or more, a plurality of L b2 and Y b1 are preferably the same group. R b1 Examples of the alkyl group having 1 to 6 carbon atoms include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, 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 groups in which -CH2- in an alkyl group 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. 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. R b1 are each independently preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms (wherein —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 (wherein —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 an integer of 0 to 4 (i.e., nb3-1 is an integer of 0 to 3), 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, R b1 Preferably, 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 the groups 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. Examples of the anion (I-A2) include the following anions. Among them, anions represented by formulas (I-a2-1) to (I-a2-32) are preferred, and anions represented by formulas (I-a2-1) to (I-a2-11) and (I-a2-16) to (I-a2-32) are more preferred. The anions of formulas (I-a2-1) to (I-a2-32) below may be formed by adding some R b1is omitted, and may contain substituents not shown. TIFF2026026040000051.tif173158

[0048] The sulfonylimide anion or sulfonylmethide anion includes an anion represented by formula (IB). TIFF2026026040000052.tif1186[In formula (IB), A 1 represents a nitrogen atom or a carbon atom. L b2’ represents 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-, -SO- or -SO2-. Y b1’ represents an optionally substituted methyl group or an optionally substituted cyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. nb5 represents an integer of 2 or 3. When nb5 is 2, A 1 is a nitrogen atom and nb5 is 3, then A 1 is a carbon atom. The groups in parentheses may be the same or different, and two groups in parentheses are bonded to form A 1 may form a ring containing In formula (IB), L b2’ and Y b1’ Examples of the hydrocarbon group, cyclic hydrocarbon group and substituent are L in formula (IA). b2 and Y b1 The same groups as those shown below can be mentioned. In formula (IB), L b2’ is a single bond, *-L b23 -, *-L b23 -X 2 -or*-L b23 -X 2 -W 2 -X 3 -(L b23represents a chain hydrocarbon group having 1 to 6 carbon atoms which may contain a fluorine atom. 2 and X 3 each independently represents -O-, -CO-O-, -O-CO-, -O-CO-O- or -O-. W 2 represents an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-. * represents a bonding site with SO2. ) is preferred. In formula (IB), Y b1’ is preferably a methyl group having a fluorine atom or 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-, -SO-, or -SO2-), and more preferably a trifluoromethyl group, 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-, -SO-, or -SO2-), or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. Specifically, it is preferably a trifluoromethyl group or a group represented by formulae (Y1) to (Y36) exemplified in formula (I-A1). In formula (IB), two -SO2-L b2’ -Y b1’ Together they form A 1 When a ring containing the formula (I-B') is formed, examples thereof include anions represented by the formula (I-B'). TIFF2026026040000053.tif22117[In formula (I-B'), A 1 , Y b1’ , L b2’ and nb5 have the same meaning as in formula (IB). W b4 represents a disulfonylimide ring or disulfonylmide ring having 2 to 12 carbon atoms which may have a fluorine atom.] W b4The disulfonylimide ring or disulfonylmide ring preferably has 3 to 12 carbon atoms, more preferably 3 to 6 carbon atoms, and the hydrogen atom of the methylene group contained in the ring is preferably substituted with a fluorine atom.

[0049] Examples of the anion represented by formula (IB) include the following: Among these, the anions represented by formulae (I-a3-1), (I-a3-2), and (I-a3-12) to (I-a3-14) are preferred. TIFF2026026040000054.tif254162

[0050] Specific examples of the salt (I) include salts formed by any combination of the above-mentioned cations and anions. Specific examples of the salt (I) are shown in the table below. In the table below, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation, and "~" indicates that salt (I) corresponds to anion (I) or cation (I), respectively. For example, salt (I-1) is a salt consisting of an anion represented by formula (Ia-1) and a cation represented by formula (Ic-1), salt (I-2) is a salt consisting of an anion represented by formula (Ia-2) and a cation represented by formula (Ic-1), and salt (I-71) is a salt consisting of an anion represented by formula (Ia-1) and a cation represented by formula (Ic-2). Furthermore, salt (I-7001) is a salt consisting of an anion represented by formula (I-a2-1) and a cation represented by formula (Ic-1), salt (I-7002) is a salt consisting of an anion represented by formula (I-a2-2) and a cation represented by formula (Ic-1), and salt (I-7021) is a salt consisting of an anion represented by formula (I-a2-1) and a cation represented by formula (Ic-2). TIFF2026026040000055.tif44135 [Table 1] TIFF2026026040000057.tif249164 TIFF2026026040000058.tif244164 TIFF2026026040000059.tif244164 TIFF2026026040000060.tif249164 TIFF2026026040000061.tif104155

[0051] Among these, salt (I) is preferably a salt obtained by combining an anion represented by any one of formulas (Ia-1) to (Ia-4), (Ia-7) to (Ia-11), (Ia-14) to (Ia-30), (Ia-35) to (Ia-70), and (I-a2-1) to (I-a2-26) with a cation represented by any one of formulas (Ic-1) to (Ic-105).

[0052] <Method for producing salt (I)> The salt (I) can be produced by reacting a salt represented by formula (Ia) with a salt represented by formula (Ib) in a solvent. TIFF2026026040000062.tif76170 [wherein all symbols have the same meanings as above. X x represents a chlorine atom, a bromine atom, or an iodine atom. A , R B and R C each independently represents a hydrocarbon group having 1 to 12 carbon atoms, or R A , R B and R C may combine to form an aromatic ring. D represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.] Examples of the solvent include chloroform, monochlorobenzene, acetonitrile, and water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours.

[0053] Examples of the salt represented by formula (Ib) include salts represented by the following formula: These salts can be produced by the same method as that described in JP-A Nos. 2011-116747 and 2016-047815, or by known production methods. TIFF2026026040000063.tif174148

[0054] The salt represented by formula (Ia) can be produced by reacting the salt represented by formula (Ic) with the compound represented by formula (I-d1) in a solvent in the presence of a catalyst, and optionally treating with an acid. TIFF2026026040000064.tif67170 [wherein all symbols have the same meanings as above. R aa is a fluorine atom or -(CO) aa represents —OH, and aa represents 0 or 1. 1’ is A 1 From -(CO) aa represents a group excluding -O-.] Examples of the catalyst include potassium carbonate, sodium hydride, carbonyldiimidazole, and 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride. Examples of the solvent include chloroform, monochlorobenzene, acetonitrile, and water. The acid includes hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, and the like. The reaction temperature is usually 15° C. to 100° C., and the reaction time is usually 0.5 to 24 hours.

[0055] Examples of the salt represented by formula (Ic) include salts represented by the following formula, which are readily available on the market. TIFF2026026040000065.tif125162

[0056] Examples of the compound represented by formula (I-d1) include the compounds represented by the following formulas, which are readily available on the market. TIFF2026026040000066.tif163138

[0057] <Acid generator> The acid generator of the present invention may contain one kind of salt (I) or may contain two or more kinds of salt (I). The acid generator of the present invention may contain, in addition to the salt (I), a known compound that acts as an acid generator in the resist field (hereinafter, sometimes referred to as "compound (B)" or "acid generator (B)"). The compound (B) may be used alone or in combination of two or more. Compound (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), etc. 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 anions, sulfonylimide anions, sulfonylmethide anions, and carboxylate anions. The compound (B) may be a part of the structural unit of the resin contained in the resist composition of the present invention, like the structural unit (a7) described below.

[0058] Compound (B) that can be used is a compound that generates an acid when exposed to 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. 3,914,407, and European Patent No. 126,712. Compounds produced by known methods may also be used. Compound (B) may be an acid generator having an acid labile group. For example, the compound or resin that serves as the acid generator may contain a partial structure that forms an acid labile group, and the acid labile group preferably contains group (1) or group (2) described below. When the resist composition of the present invention contains a compound having an acid labile group, it does not necessarily need to contain a resin that contains a structural unit having an acid labile group.

[0059] The acid generator (B) is preferably a salt represented by formula (B1) (hereinafter sometimes referred to as "salt (B1)" or "compound (B1)", excluding salt (I)). More preferably, it is a salt having an anion represented by formula (B1-1) (hereinafter sometimes referred to as "anion (B1-1)", excluding anion (I)) or an anion represented by formula (B1-2) (hereinafter sometimes referred to as "anion (B1-2)", excluding anion (I)). The acid generator (B) is also preferably a salt represented by formula (B2) (hereinafter sometimes referred to as "salt (B2)" or "compound (B2)", excluding salt (I)). TIFF2026026040000067.tif1395[In formula (B1), L b1 , L b2 , Y b1 and nb1 have the same meaning as in formula (IA). Z1 + represents an organic cation, excluding the cation represented by formula (IC). TIFF2026026040000068.tif30121[In formula (B1-1), Q b1 , Q b2 , Q b3 , Q b4 , z1, X 1 , L b3 , L b2 , Y b1 and nb2 have the same meaning as in formula (I-A1). TIFF2026026040000069.tif2879[In formula (B1-2), L b2 , Y b1 , R b1 , nb4 and nb3 have the same meaning as in formula (I-A2). TIFF2026026040000070.tif1193[In formula (B2), A 1 , L b2’ , Y b1’ and nb5 have the same meaning as in formula (IB). Z2 + represents an organic cation, excluding the cation represented by formula (IC).

[0060] L in formula (B1) b1 , L b2 , Y b1 and nb1 are L in the above formula (IA), respectively. b1 , L b2 , Y b1 and nb1, and the like. Q in formula (B1-1) b1 , Q b2 , Q b3 , Q b4 , z1, X 1 , L b3 , L b2 , Y b1 and nb2 are the Q groups in the above formula (I-A1), respectively. b1 , Q b2 , Q b3 , Q b4 , z1, X 1 , L b3 , L b2 , Y b1 and nb2, and the like. Examples of the sulfonate anion in formula (B1-1) include the same anions as those represented by formula (I-A1). L in formula (B1-2) b2 , Y b1 , R b1 , nb4 and nb3 are L in the above formula (I-A2), respectively. b2 , Y b1 , R b1 , nb4 and nb3, and the like. Examples of the sulfonate anion in formula (B1-2) include the same anions as those represented by formula (I-A2). A in formula (B2) 1 , L b2’ , Y b1’ and nb5 are A in the above formula (IB), respectively. 1 , L b2’ , Y b1’ and nb5, and the like. The sulfonylimide anion or sulfonylmethide anion in formula (B2) may be the same as the anion represented by formula (IB). In another embodiment of the acid generator (B), a salt in which the anion in the salt represented by formula (B1) or the like is replaced with a carboxylate anion or the like can also be suitably used as the acid generator (B). Examples of the carboxylate anion include the following. TIFF2026026040000071.tif43155

[0061] Z1 + and Z2 + Examples of the organic cation include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations or aryl iodonium cations are more preferred. Specific examples include cations represented by any of formulas (b2-1) to (b2-5) (hereinafter, sometimes referred to as "cation (b2-1)" depending on the formula number). TIFF2026026040000072.tif84159[Formula (b2-1) to (b2-5), R b4 ~R b6 each independently represent a chain hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, a hydrogen atom contained in the chain hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5and may be bonded to each other to form a ring together with the sulfur atom to which they are attached, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m7 and n8 each independently represent an integer of 0 to 5; When m7 is 2 or more, multiple R b7 may be the same or different, and when n8 is 2 or more, multiple R b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 and may be bonded to each other to form a ring together with the sulfur atom to which they are attached, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 and may be bonded to each other to form a ring including the -CH-CO- to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 and Rb21 ~R b26 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b13 and R b14 and R b21 and R b22 and may be bonded to each other to form a ring containing a sulfur atom together with the benzene ring to which they are attached, and -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b27 ~R b29 each independently represents a hydrogen atom or a group containing an acid labile group. L b31 and L b41 ~L b43 each independently represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of 0 to 5. q2 and r2 each independently represent an integer of 0 to 4; u2 represents 0 or 1. When o2 is 2 or more, multiple R b13 are the same or different, and when p2 is 2 or more, multiple R b14 are the same or different, and when q2 is 2 or more, multiple R b15 are the same or different, and when r2 is 2 or more, multiple R b16 are the same or different, and when s2 is 2 or more, multiple R b17 are the same or different, and when t2 is 2 or more, multiple R b18 are the same or different. o21, p22, q23, r24, t25 and s26 each independently represent an integer of 0 to 4. When o21, p22, q23, r24, t25 and s26 are each 2 or more, multiple R b21 ~R b26 are the same or different. u3 represents an integer of 1 to 3, and satisfies 1≦u3+q23≦5. u4 and u5 each independently represent an integer of 0 to 3, and satisfy 0≦u4+o21≦5 and 0≦u5+p22≦5. When u3, u4, and u5 each represent 2 or more, the groups in the parentheses are the same or different. When u2 is 0, any one of o2, p2, q2, and r2 is 1 or more, and R b13 ~R b16 At least one of o2, p2, s2, t2, q2 and r2 is preferably a halogen atom, and when u2 is 1, any one of o2, p2, s2, t2, q2 and r2 is 1 or more, and R b13 ~R b18 At least one of these is preferably a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, and more preferably 1. When u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom. The aliphatic hydrocarbon group refers to a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl. In particular, R b9 ~R b12 The chain hydrocarbon group preferably has 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and cyclodecyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups: TIFF2026026040000073.tif11157 In particular, R b9 ~R b12 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, and more preferably has 4 to 12 carbon atoms. Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-methyladamantan-2-yl group, a 2-ethyladamantan-2-yl group, a 2-isopropyladamantan-2-yl group, a methylnorbornyl group, an isobornyl group, etc. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms in the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The fluorinated alkyl group refers to an alkyl group having 1 to 12 carbon atoms and a fluorine atom, and examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluorobutyl group, etc. The number of carbon atoms in the fluorinated alkyl group is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 4. Examples of aromatic hydrocarbon groups include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, etc. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples thereof include aromatic hydrocarbon groups having a chain hydrocarbon group (such as a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, etc.) and aromatic hydrocarbon groups having an alicyclic hydrocarbon group (such as a p-cyclohexylphenyl group, a p-adamantylphenyl group, etc.). When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. Examples of aromatic hydrocarbon groups in which hydrogen atoms are substituted with alkoxy groups include p-methoxyphenyl groups. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as benzyl, phenethyl, phenylpropyl, trityl, naphthylmethyl, and naphthylethyl. 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 alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, an isopropylcarbonyloxy group, a butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, and a 2-ethylhexylcarbonyloxy group. R b4 and R b5 and bond to each other together with the sulfur atom to which they are bonded to form a ring which may be monocyclic, polycyclic, aromatic, non-aromatic, saturated, or unsaturated. This ring may be a ring having 3 to 18 carbon atoms, preferably a ring having 4 to 18 carbon atoms. The ring containing a sulfur atom may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring, for example, the following rings. * represents a bonding site. TIFF2026026040000074.tif24142R b9 and R b10 The ring formed by these together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring. Examples thereof include a thiolan-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and a 1,4-oxathian-4-ium ring. R b11 and R b12 The ring formed by combining these may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include a 3- to 12-membered ring, and preferably a 3- to 7-membered ring. Examples include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring. R b27 ~R b29Examples of groups containing an acid labile group include -R c30 , -CO-OR c30 or -L c10 -CO-OR c30 A group represented by (L c10 represents an alkanediyl group having 1 to 6 carbon atoms, and R c30 represents an acid labile group. R b27 ~R b29 Examples of the acid labile group include the groups represented by the above formula (1) or formula (2). R b27 ~R b29 The acid labile group includes groups represented by formula (1) or (2).

[0062] Among the cations (b2-1) to (b2-5), the cation (b2-1), the cation (b2-4) or the cation (b2-5) is preferred. Examples of the cation (b2-1) include the following cations. TIFF2026026040000075.tif172164

[0063] TIFF2026026040000076.tif50161 Examples of the cation (b2-2) include the following cations. TIFF2026026040000077.tif18150Examples of the cation (b2-3) include the following cations. TIFF2026026040000078.tif26140Examples of the cation (b2-4) include the following cations. TIFF2026026040000079.tif120163Examples of the cation (b2-5) include the following cations. TIFF2026026040000080.tif101164

[0064] The acid generator (B) is a combination of the above-mentioned anions and the above-mentioned organic cations, and these can be combined arbitrarily. Preferred examples of the acid generator (B) include combinations of anions represented by any of formulas (Ia-1) to (Ia-4), (Ia-7) to (Ia-11), (Ia-14) to (Ia-30), (Ia-35) to (Ia-70), (I-a2-1) to (I-a2-11), (I-a2-16) to (I-a2-20), (I-a3-1) to (I-a3-3), and (I-a3-11) to (I-a3-14) with cations (b2-1), (b2-2), (b2-3), (b2-4), and (b2-5).

[0065] Preferred examples of the acid generator (B) include those represented by formulae (B1-1) to (B1-106), (B2-1) to (B2-20), and (B3-1) to (B3-28). Among these, those containing an arylsulfonium cation are preferred, and those represented by formulae (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), (B1-31) to (B1-105), (B2-1) to (B2-20), and (B3-1) to (B3-28) are particularly preferred. JPEG2026026040000081.jpg176161

[0066] TIFF2026026040000082.tif254158

[0067] TIFF2026026040000083.tif254158

[0068] TIFF2026026040000084.tif254160

[0069] TIFF2026026040000085.tif253162

[0070] TIFF2026026040000086.tif249150

[0071] TIFF2026026040000087.tif186160

[0072] When the acid generator contains a salt (I) and an acid generator (B), the ratio of the salt (I) to the acid generator (B) (mass ratio; salt (I):acid generator (B)) is usually 1:99 to 99:1, preferably 2:98 to 98:2, more preferably 5:95 to 95:5, even more preferably 10:90 to 90:10, and particularly preferably 15:85 to 85:15.

[0073] <Resist composition> The resist composition of the present invention is a resist composition that contains an acid generator that includes a salt (I). In the resist composition of the present invention, the content of salt (I) relative to the solid content of the resist composition is preferably from 0.1% to 99.9% by mass, more preferably from 1% to 90% by mass, even more preferably from 5% to 85% by mass, still more preferably from 10% to 80% by mass, even more preferably from 20% to 75% by mass, and even more preferably from 30% to 70% by mass. In the resist composition of the present invention, the total content of the salt (I), acid generator (B), etc., relative to the solid content of the resist composition, is preferably from 0.1 mass % to 99.9 mass %, more preferably from 1 mass % to 90 mass %, even more preferably from 5 mass % to 85 mass %, still more preferably from 10 mass % to 80 mass %, even more preferably from 20 mass % to 75 mass %, and still more preferably from 30 mass % to 70 mass %.

[0074] The resist composition of the present invention may further contain a compound containing a structure represented by formula (L0) (hereinafter, may be referred to as "compound (L0)"). Compound (L0) is a compound containing one or more structures represented by formula (L0) as a partial structure, and is a compound containing an aromatic hydrocarbon ring having a phenolic hydroxy group or a benzoic carboxy group, or a compound in which the hydroxy group or carboxy group of such a compound is protected with an acid labile group. When the resist composition of the present invention contains compound (L0), compound (L0) is preferably contained in the form of a structural unit constituting a resin. TIFF2026026040000088.tif2372 [In formula (L0), all symbols have the same meanings as defined above.] Ar lk Examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthrene ring. Ar lk The substituents that the aromatic hydrocarbon ring may have include R lk11 and R lk22 The same groups as those exemplified above are exemplified. Ar lk is preferably a benzene ring or a naphthalene ring which may have a substituent, and more preferably a benzene ring which may have a substituent. R lk Examples of the acid labile group include the group represented by the formula (1a) and the group represented by the formula (2a) described above, and the group represented by the formula (1) and the group represented by the formula (2) described below. Of these, the group represented by the formula (2a) is preferred. lk may be any integer equal to or greater than 2. Furthermore, lk may be, for example, any integer equal to or less than 13. Among these, lk is preferably any integer from 1 to 11, more preferably any integer from 1 to 9, even more preferably any integer from 1 to 7, still more preferably any integer from 1 to 6, even more preferably any integer from 1 to 5, and still more preferably any integer from 1 to 4. Io may be any integer equal to or greater than 2. Furthermore, Io may be, for example, any integer equal to or less than 13. Among these, Io is preferably any integer from 1 to 11, more preferably any integer from 1 to 9, even more preferably any integer from 1 to 7, still more preferably any integer from 1 to 6, even more preferably any integer from 1 to 5, and still more preferably any integer from 1 to 4.

[0075] Examples of the compound (L0) include a compound represented by formula (LX) (hereinafter sometimes referred to as "compound (LX)"). TIFF2026026040000089.tif23130 [In formula (LX), all symbols have the same meanings as defined above.]

[0076] Ar k1 and Ar k2 As the aromatic hydrocarbon ring, Ar lk Examples of the aromatic hydrocarbon ring include the same groups as those exemplified above. R lk1 and R lk2 The acid labile group in lk Examples of the acid labile group include the same groups as those exemplified above as the acid labile group. Examples of the hydrocarbon group of Lx include a chain hydrocarbon group, a monocyclic or polycyclic (including a spiro ring, a fused ring, or a bridged ring) alicyclic hydrocarbon group, and an aromatic hydrocarbon group, and may be a group combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group). The hydrocarbon group of Lx is a (lx2+1)-valent hydrocarbon group, and can be a divalent to heptavalent hydrocarbon group depending on lx2. The number of carbon atoms in the hydrocarbon group is preferably 1 to 72, more preferably 1 to 60, even more preferably 1 to 48, still more preferably 1 to 36, and even more preferably 1 to 24. Examples of the chain hydrocarbon group include an alkanediyl group, and examples of the alkanediyl group include 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, and a tetradecane-1,14-diyl group. and branched alkanediyl groups such as 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. The branched alkanediyl group may have a terminal methyl group. Further, examples of the chain hydrocarbon group include groups in which one or more hydrogen atoms of the above groups have been replaced with bonding sites. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, preferably 1 to 10, even more preferably 1 to 9, still more preferably 1 to 8, even more preferably 1 to 6, and even more preferably 1 to 4. Examples of the alicyclic hydrocarbon group include monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl, norbornane-2,5-diyl, adamantane-1,5-diyl, and adamantane-2,6-diyl; cycloalkyl groups such as spirocyclohexane-1,2′-cyclopentane and spiroadamantane-2,3′-cyclopentane; and spirocyclic alicyclic hydrocarbon groups such as spiro rings having a cycloalkyl group bonded to a norbornyl group or an adamantyl group via a spiro bond. Alicyclic hydrocarbon groups also include groups in which one or more hydrogen atoms of the above groups have been replaced with bonding sites. Examples of the alicyclic hydrocarbon group include the following groups: The binding site can be at any position. TIFF2026026040000090.tif41165 The number of carbon atoms in the alicyclic hydrocarbon group is, for example, 3 to 72, and may be 3 to 60, preferably 3 to 24, more preferably 3 to 20, even more preferably 3 to 18, still 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, and a phenanthrylene group. The aromatic hydrocarbon group also includes groups in which one or more hydrogen atoms of the above groups have been replaced with a bonding site. The aromatic hydrocarbon group may have 6 to 72 carbon atoms, may have 6 to 60 carbon atoms, is preferably 6 to 24 carbon atoms, is more preferably 6 to 20 carbon atoms, is further preferably 6 to 18 carbon atoms, is further preferably 6 to 14 carbon atoms, and is further more preferably 6 to 10 carbon atoms. Examples of the group combining two or more groups include a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group, a group combining an aromatic hydrocarbon group with a chain hydrocarbon group, and a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined. In addition, when any group is Ar k1 or Ar k2 may be bound to Examples of groups combining an alicyclic hydrocarbon group and a chain hydrocarbon group include -alicyclic hydrocarbon group-chain hydrocarbon group-, -chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, and -chain hydrocarbon group-alicyclic hydrocarbon group-. Examples of groups combining an aromatic hydrocarbon group and a chain hydrocarbon group include -aromatic hydrocarbon group-chain hydrocarbon group-, -chain hydrocarbon group-aromatic hydrocarbon group-chain hydrocarbon group-, and -chain hydrocarbon group-aromatic hydrocarbon group-. 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-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-. Combined groups also include groups in which one or more hydrogen atoms of the above groups are replaced with a bonding site. The -CH2- contained in the hydrocarbon group of Lx is -O-, -S-, -SO2-, -SO-, -NR 11 It may be replaced by - or -CO-. -CH2- in the hydrocarbon group of Lx is -O-, -S-, -SO2-, -SO-, -NR 11 When it is replaced with - or -CO-, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the hydrocarbon group. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR 11Examples of groups substituted with - or -CO- include a hydroxy group, a carboxy group, a thiol group, an amino group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkoxyalkyl group, a hydroxyalkyl group, an alkylthio group, an alkylsulfonyl group, an alkylamino group, an alkylpeptide group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, a peptide group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediyloxycarbonyloxy group, an alkanediylthio group, an alkanediylsulfonyl group, an alkanediylamino group, an alkanediylpeptide group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group comprising a combination of two or more of these groups. 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. In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be -O-, -S-, -CO-, -SO-, -NR 11 The group substituted with - or -SO2- includes the same groups as those exemplified in this specification, within the upper limit of the carbon number. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR 11 Groups substituted with - or -CO- also include groups in which one or more hydrogen atoms of the above groups have been replaced with a bonding site. Examples of the substituent that Lx may have include a halogen atom and a cyano group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. When Lx is a group formed by combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with a chain hydrocarbon group such as an alkyl group, the chain hydrocarbon group such as an alkyl group can be used as a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. The —CH2— contained in the chain hydrocarbon group such as the alkyl group contained in Lx is —O—, —CO—, —S—, —SO—, —NR 11 By replacing Lx with - or -SO2-, Lx can essentially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkylamino group, an amino group, a thiol group, an alkylthio group, an alkylsulfonyl group, or an alkylpeptide group. The substituent that Lx may have is R lk11 and R lk22 Also included are groups similar to those exemplified above.

[0077] R lk11 and R lk22 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R lk11 and R lk22 Examples of the hydrocarbon group include chain hydrocarbon groups such as alkyl groups and alkanediyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups. The alkyl group is a linear 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, and examples thereof include 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 tetradecane-1,16-diyl group, a pentane-1,17-diyl group, a pentane-1,18-diyl group, a pentane-1,19-diyl group, a pentane-1,20-diyl group, a pentane-1,21-diyl group, a pentane-1,22-diyl group, a pentane-1,23-diyl group, a pentane-1,24-diyl group, a pentane-1,25-diyl group, a pentane-1,26-diyl group, a pentane-1,27-diyl group, a pentane-1,28-diyl group, a pentane-1,29-diyl group, a pentane-1,30-diyl group, a pentane-1,31-diyl group, a pentane-1,32-diyl group, a pentane-1,33-diyl group, a pentane-1,34-diyl group, a pentane-1,35-diyl group, a pentane-1,36-diyl group, a pentane-1,3 Examples of the alkanediyl group include linear alkanediyl groups such as decane-1,15-diyl, hexadecane-1,16-diyl, and heptadecane-1,17-diyl, and branched alkanediyl groups such as 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. The terminal of the branched alkanediyl group may be a methyl 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, even more preferably 1 to 4 carbon atoms, and even more preferably 1 to 3 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of the alicyclic hydrocarbon group include the groups shown below: The bonding site can be at any position. TIFF2026026040000091.tif41165Specifically, monocyclic alicyclic hydrocarbon groups include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl. Polycyclic alicyclic hydrocarbon groups include polycyclic cycloalkyl groups such as decahydronaphthyl, adamantyl, and norbornyl. Spirocyclic alicyclic hydrocarbon groups include 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 via a spiro bond. 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 aromatic hydrocarbon group preferably has 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. Examples of groups formed by combining two or more groups include groups formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group (for example, aromatic hydrocarbon group-alkanediyl group-*, alkyl group-aromatic hydrocarbon group-*, alkyl group-aromatic hydrocarbon group-alkanediyl group-*, and the -CH2- contained in the alkanediyl group and the alkyl group can be -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are combined (for example, an alicyclic hydrocarbon group-alkanediyl group-*, an alkyl group-alicyclic hydrocarbon group-*, an alkyl group-alicyclic hydrocarbon group-alkanediyl group-*, and the -CH2- contained in the alicyclic hydrocarbon group, the alkanediyl group, and the alkyl group may be replaced by -O-, -CO-, -S-, -SO-, -NR 11- or -SO2-), a group in which an aromatic hydrocarbon group and an alicyclic hydrocarbon group are combined (for example, an aromatic hydrocarbon group-alicyclic hydrocarbon group-*, an alicyclic hydrocarbon group-aromatic hydrocarbon group-*, and the -CH2- contained in the alicyclic hydrocarbon group can be replaced by -O-, -CO-, -S-, -SO-, -NR 11 - or -SO2-.) * indicates a binding 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, 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. R lk11 and R lk22 -CH2- contained in the hydrocarbon group represented by the formula: 11 When the hydrocarbon group is substituted with - or -SO2-, the number of carbon atoms before the substitution is taken as the total number of carbon atoms in the hydrocarbon group. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR 11Examples of the group substituted with - or -CO- include the same groups as those exemplified for Lx, within the upper limit of the carbon number. R lk11 and R lk22 Examples of the substituent that the hydrocarbon group may have include a halogen atom and a cyano group. Examples of the halogen atom include the same groups as those mentioned above. R lk11 and R lk22 is a hydrocarbon group having a halogen atom, R lk11 and R lk22 Examples 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. The term "haloalkyl group" refers to an alkyl group having a halogen atom, and examples of the haloalkyl group include C1-12 haloalkyl groups such as C1-12 fluorinated alkyl groups, C1-12 chlorinated alkyl groups, C1-12 brominated alkyl groups, and C1-12 iodinated alkyl groups. Specific examples of the haloalkyl group include C1-12 perfluoroalkyl groups (trifluoromethyl, pentafluoroethyl, heptafluoropropyl, nonafluorobutyl, etc.), 2,2,2-trifluoroethyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 3,3,4,4,4-pentafluorobutyl, chloromethyl, bromomethyl, and iodomethyl. 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. -CH2- contained in the haloalkyl group may be replaced by -O-, -CO- or the like, and examples of such groups include haloalkoxy groups, haloalkoxycarbonyl groups, haloalkylcarbonyl groups, haloalkylcarbonyloxy groups, etc. Specific examples include haloalkoxy groups having 1 to 11 carbon atoms, haloalkoxycarbonyl groups having 2 to 11 carbon atoms, haloalkylcarbonyl groups having 2 to 12 carbon atoms, haloalkylcarbonyloxy groups having 2 to 11 carbon atoms, etc., and examples include groups in which one or more hydrogen atoms of the groups exemplified above are replaced with halogen atoms. The hydrocarbon group may have one or more substituents.

[0078] Compound (LX) includes a compound represented by formula (LX-0) (hereinafter may be referred to as "compound (LX-0)"). Compound (LX-0) is preferably a compound represented by formula (LX-1) (hereinafter may be referred to as "compound (LX-1)"). TIFF2026026040000092.tif23125 [In formula (LX-0), symbols other than those below have the same meanings as defined above. lk1 represents an integer of 1 to 5, and when lk1 is 2 or more, the groups in the parentheses may be the same or different. lk11 represents an integer of 0 to 4, and satisfies 1≦lk1+lk11≦5, and when lk11 is 2 or more, the groups in the parentheses may be the same or different. lk2 represents an integer of 1 to 5, and when lk2 is 2 or greater, the groups in the parentheses may be the same or different. lk22 represents an integer of 0 to 4, and satisfies 1≦lk2+lk22≦5, and when lk22 is 2 or more, the groups in the parentheses may be the same or different.] TIFF2026026040000093.tif41147 [In formula (LX-1), symbols other than those shown below have the same meanings as defined above. X lk3 represents a single bond or a carbonyl group. R lk3represents a hydrogen atom or an acid labile group. Lx1 and Lx2 each independently represent a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -CO-, -S-, -SO-, and -NR 11 It may be replaced by - or -SO2-. R lk33 represents a hydrocarbon group having 1 to 20 carbon atoms which may have a halogen atom or a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -CO-, -S-, -SO-, -NR 11 It may be replaced by - or -SO2-. lx3 represents an integer of 0 to 6, and when lx3 is 2 or greater, the groups in the parentheses may be the same or different. lk3 represents an integer of 1 to 4, and when lk3 is 2 or greater, the groups in the parentheses may be the same or different. lk33 represents an integer of 0 to 3, and satisfies 1≦lk3+lk33≦4, and when lk33 is 2 or more, the groups in the parentheses may be the same or different.] Examples of the hydrocarbon groups of Lx1 and Lx2 and the substituents that the hydrocarbon groups may have include the same groups as the hydrocarbon groups exemplified for Lx and the substituents that the hydrocarbon groups may have, within the range permitted by the upper limit of the number of carbon atoms, etc. R lk33 The halogen atoms, hydrocarbon groups, and substituents that the hydrocarbon groups may have are, within the limits permitted by the upper limit of the number of carbon atoms, R lk11 and R lk22 Examples of the substituents include the halogen atoms, hydrocarbon groups, and groups that may be contained in the hydrocarbon groups exemplified above. R lk11 and Lx or R lk22 and Lx may be bonded to each other to form a ring. In this case, the ring is lk11 and R lk22are bonded to an aromatic hydrocarbon ring, and thus form a fused ring fused with the aromatic hydrocarbon ring or a spiro ring spiro-bonded with the aromatic hydrocarbon ring. The total number of carbon atoms in the fused ring or spiro ring is, for example, 3 to 38, and may be 3 to 28, preferably 3 to 24, more preferably 3 to 20, and even more preferably 3 to 18. The fused ring or spiro ring may contain one or more of -O-, -CO-, -S-, -SO-, -NR 11 The ring may contain - or -SO2-. lk11 )-Lx- or aromatic hydrocarbon ring (-R lk22 )-Lx-, R lk11 and Lx or R lk22 Examples of the ring formed by bonding of R and Lx include the following groups. Although the following groups are omitted, at least one R lk1 -OX lk1 -or R lk2 -OX lk2 - has other R lk11 or R lk22 * represents the bonding site to the aromatic hydrocarbon ring. TIFF2026026040000094.tif18111R lk11 and R lk22 may be bonded to each other to form a ring. In this case, examples of the ring include a ring having a structure represented by the formula (LX-13) described below.

[0079] Compound (LX-1) is preferably a compound represented by formula (LX-11), formula (LX-12), or formula (LX-13) (hereinafter, these may be referred to as "compound (LX-11)," "compound (LX-12)," or "compound (LX-13)," respectively). TIFF2026026040000095.tif41117

[0080] TIFF2026026040000096.tif41150

[0081] TIFF2026026040000097.tif53155 [In formula (LX-11), formula (LX-12) and formula (LX-13), Symbols other than those listed below have the same meanings as above. Ly represents a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is selected from -O-, -CO-, -S-, -SO-, and -NR 11 - or -SO2- may be replaced.] Examples of the hydrocarbon group for Ly and the substituents that the hydrocarbon group may have include the same groups as the hydrocarbon groups exemplified for Lx and the substituents that the hydrocarbon group may have, within the range permitted by the upper limit of the number of carbon atoms, etc. lk1 and lk2 are each independently preferably an integer of 1 to 4, more preferably an integer of 1 to 3, and even more preferably 1 or 2. lk11 and lk22 are each independently preferably an integer of 0 to 3, and more preferably an integer of 0 to 2. lk3 is preferably an integer of 1 to 3, and more preferably 1 or 2. lk33 is preferably an integer of 0 to 2. lx2 is preferably an integer of 1 to 5, more preferably an integer of 1 to 4, even more preferably an integer of 1 to 3, and even more preferably 1 or 2. lx3 is preferably an integer of 0 to 5, more preferably an integer of 0 to 4, even more preferably an integer of 0 to 3, and even more preferably an integer of 0 to 2. R lk11 , R lk22 and R lk33are each independently preferably a halogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group or the haloalkyl group may be replaced with -O- or -CO-), more preferably a halogen atom, an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), or a haloalkyl group having 1 to 4 carbon atoms, still more preferably an iodine atom, a fluorine atom, an alkyl group having 1 to 3 carbon atoms, a hydroxy group, an alkoxy group having 1 to 3 carbon atoms, a hydroxyalkyl group having 1 to 3 carbon atoms, a carboxy group, or a fluorinated alkyl group having 1 to 3 carbon atoms, still more preferably an iodine atom, a fluorine atom, an alkyl group having 1 to 3 carbon atoms, a hydroxy group, an alkoxy group having 1 to 3 carbon atoms, a carboxy group, or a perfluoroalkyl group having 1 to 3 carbon atoms, and still more preferably an iodine atom, a fluorine atom, a methyl group, a hydroxy group, a methoxy group, an ethoxy group, or a trifluoromethyl group. Lx1, Lx2 and Ly are each independently preferably a chain hydrocarbon group having 1 to 10 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-) or a group in which a chain hydrocarbon group having 1 to 6 carbon atoms is combined with a cyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the chain hydrocarbon group and the cyclic hydrocarbon group may be replaced by -O- or -CO-), and are each 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-). The —CH2— contained therein may be replaced by —O— or —CO—), or a group in which a chain hydrocarbon group of 1 to 4 carbon atoms is combined with a cyclic hydrocarbon group of 3 to 16 carbon atoms (the —CH2— contained in the chain hydrocarbon group and the cyclic hydrocarbon group may be replaced by —O— or —CO—), and even more preferably a chain hydrocarbon group of 1 to 6 carbon atoms or a group in which a chain hydrocarbon group of 1 to 4 carbon atoms is combined with a cyclic hydrocarbon group of 3 to 12 carbon atoms. Also, R lk11 and Lx1 or R lk22 and Lx2 are preferably bonded to form a ring, and R lk11 and R lk22are also preferably bonded to form a ring.

[0082] The compound (L0) may be a low-molecular-weight compound, which is a compound having a weight-average molecular weight of less than 10,000. The weight-average molecular weight of compound (L0) is preferably 7,500 or less, more preferably 5,000 or less, even more preferably 4,000 or less, even more preferably 3,500 or less, even more preferably 3,000 or less, even more preferably 2,500 or less, even more preferably 2,000 or less, and even more preferably 1,500 or less. Also, it may be 100 or more, preferably 120 or more, more preferably 150 or more, even more preferably 200 or more, and even more preferably 300 or more.

[0083] Among the compounds (L0), the compound (X) containing an aromatic hydrocarbon ring having a hydroxy group or a carboxy group lk is a single bond or a carbonyl group, and R lk is a hydrogen atom), the compounds represented by the following formulas may be mentioned. TIFF2026026040000098.tif237164 Among the compounds (L0), compounds (X) containing an aromatic hydrocarbon ring having a hydroxyl group or a carboxyl group lk is a single bond or a carbonyl group, and R lk is a hydrogen atom), compounds in which the hydroxy group of the above compounds is replaced with a carboxy group or vice versa, may also be mentioned. Compound (L0) may have both a hydroxy group and a carboxy group.

[0084] Among the compounds (L0), examples of compounds containing an aromatic hydrocarbon ring having a hydroxy group or a carboxy group, in which the hydroxy group or the carboxy group is protected with an acid labile group, include compounds represented by the following formula: Among compounds (L0), compounds containing an aromatic hydrocarbon ring having a hydroxy group or a carboxy group, in which the hydroxy group or the carboxy group is protected with an acid labile group, include compounds in which the ethoxyethoxy group of the above compound is replaced with an ethoxyethoxycarbonyl group, or the ethoxyethoxycarbonyl group is replaced with an ethoxyethoxy group. Compound (L0) may have both an ethoxyethoxy group and an ethoxyethoxycarbonyl group.

[0085] In the resist composition of the present invention, the content of compound (L0) relative to the solid content of the resist composition is 0.1% by mass or more, preferably 0.3% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more. It can also be 90% by mass or less, preferably 70% by mass or less, more preferably 60% by mass or less, and even more preferably 50% by mass or less. Specifically, it can be 0.1% by mass or more and 90% by mass or less, preferably 0.3% by mass or more and 70% by mass or less, more preferably 0.5% by mass or more and 60% by mass or less, and even more preferably 1% by mass or more and 50% by mass or less.

[0086] 〔resin〕 The compound (L0) may be a resin. When the compound (L0) is a resin, that is, when the compound (L0) is contained in the form of a structural unit constituting the resin, the structural unit is preferably a structural unit represented by formula (a2-A). TIFF2026026040000100.tif31127 [In formula (a2-A), all symbols have the same meanings as defined above.]

[0087] R a2 Examples of the halogen atom in the formula include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. R a2Examples 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 even more preferably a hydrogen atom or a methyl group.

[0088] A a21 Examples of the alkanediyl group include straight-chain alkyl 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. and branched alkanediyl groups such as butane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, 2-methylbutane-1,4-diyl, heptane-1,6-diyl, octane-1,7-diyl, nonane-1,8-diyl, decane-1,9-diyl, and undecane-1,10-diyl. The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, still more preferably 1 to 4, still more preferably 1 to 3, and even more preferably 1 or 2. A a21is 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 -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 When substituted with -, the number of carbon atoms before substitution is regarded as the number of carbon atoms of the alkanediyl group. A a21 Examples of the group in which -CH2- in the alkanediyl group is replaced with -O- or -CO- 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-), a peptide group (a group in which -CH2-CH2- in an ethylene group is replaced with -CO-NR a28 -), amino group (-CH2- contained in alkanediyl group is replaced by -NR a28 -), 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-), alkylamino group (a group in which -CH2- in an alkyl group is replaced with -NR a28 -), alkanediylamino group (wherein any -CH2- at any position in the alkanediyl group is replaced by -NR a28 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. Among them, A a21 -CH2- in the alkanediyl group is -O-, -CO- or -NR a28Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, and *-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, within the limits of the upper limit of the carbon number, a21 Examples of the alkanediyl groups include the same alkanediyl groups as those shown in the 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. R a27 The halogen atom and the alkyl group optionally having a halogen atom are R a2 Examples include the same as those exemplified above. R a27The alkoxy group, alkoxyalkyl group, alkoxyalkoxy group, alkylcarbonyl group, and alkylcarbonyloxy group include the same groups as exemplified herein, within the range permitted by the upper limit of the carbon number. The number of carbon atoms in the alkoxy group is preferably 1 to 4, more preferably 1 to 3. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably an alkoxy group having 1 to 3 carbon atoms, even more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 8, more preferably 2 to 4. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably an alkoxyalkyl group having 2 to 4 carbon atoms, even more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 8, more preferably 2 to 4. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably an alkoxyalkoxy group having 2 to 4 carbon atoms, and even more preferably a methoxyethoxy group or an ethoxyethoxy group. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 3. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 3. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, 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 even more preferably 0 or 1. mc is preferably 0 or 1. -X a2 -OH is a benzene ring, A a21 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 2nd position, it may be bonded to any of the 1st position and the 3rd to 8th positions. a21 When the bonding position of A is position 1, at least one of A is preferably bonded to position 3 to 6, and more preferably bonded to position 3 or 4. a21 When the bonding position is the 2nd position, it is preferably bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0089] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A Nos. 2010-204634 and 2012-12577. The structural unit (a2-A) includes structural units represented by formulae (a2-2-1) to (a2-2-32), (a2-3-1) to (a2-3-24), and structural units represented by formulae (a2-2-1) to (a2-2-32), (a2-3-1) to (a2-3-24), where R in the structural unit (a2-A) a2 and a structural unit in which the methyl group corresponding to the following formula is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. When the structural unit (a2-A) is contained in the resin, 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. It is also preferably 80 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, 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 The structural unit (a2-A) can be incorporated into a resin by polymerizing the compound (a2-A')) in the state of (a1-4). Alternatively, for example, the structural unit (a1-4) can be polymerized, followed by treatment with an acid such as p-toluenesulfonic acid, to incorporate the structural unit into a resin. Alternatively, the structural unit (a2-A) can be polymerized using acetoxystyrene or the like, followed by treatment with an alkali such as tetramethylammonium hydroxide, to incorporate the structural unit into a resin.

[0090] When the resist composition of the present invention contains a resin, the resin may contain structural units other than the structural unit represented by formula (a2-A). Examples of structural units other than the structural unit represented by formula (a2-A) include structural units having an acid labile group (hereinafter sometimes referred to as "structural unit (a1)"), structural units other than the structural unit represented by formula (a2-A) that do not have an acid labile group (hereinafter sometimes referred to as "structural unit (s)"), and structural units derived from other monomers known in the art. Here, the term "acid labile group" refers to a group that has a leaving group and that is eliminated upon contact with acid, converting the structural unit into a structural unit having a hydrophilic group (e.g., a hydroxy group or a carboxy group). In this specification, a resin containing the structural unit (a1) is referred to as resin (A).

[0091] <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) 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)). TIFF2026026040000102.tif2298[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 group combining any of these; or R a1 and R a2 are bonded to each other to form, together with the carbon atoms 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.] TIFF2026026040000103.tif2278[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 with -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.]

[0092] Ra1 , 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. R a1 , R a2 and R a3 Examples of the alkenyl group in the formula (I) include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl groups. 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): a1 , R a2 and R a3 The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms. TIFF2026026040000104.tif10159R a1 , R a2 and R a3 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 (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl 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 -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-. TIFF2026026040000105.tif26137

[0093] 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 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 atoms to which they are bonded and X, -C(R a1’ )(R a2’)-XR a3’ Examples of the groups include the following: * represents a binding site. TIFF2026026040000106.tif19124R a1’ and R a2’ At least one of these is preferably a hydrogen atom. na' is preferably 0. R a1 , R a2 , R a3 , R a1 , R a2’ and R a3’ The halogen atom that may be contained in the ring may be a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0094] 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. The group is preferably a tert-butoxycarbonyl group. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, and 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, and R a3 is an adamantyl group, ma=0, and na=1. Specific examples of the group (1) include the following: * represents a binding site. TIFF2026026040000107.tif150165

[0095] Specific examples of group (2) include the following groups: * represents a binding site. TIFF2026026040000108.tif54153

[0096] 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. When a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in a resist composition, the resolution of the resist pattern can be improved.

[0097] Examples of structural units derived from a (meth)acrylic monomer having 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, at least one structural unit selected from the group consisting of structural unit (a1-0), structural unit (a1-1), and structural unit (a1-2) is used, and more preferably at least one or two structural units selected from the group consisting of structural unit (a1-1) and structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2026026040000109.tif46148 [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 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 a04each 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 group formed by combining these, 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 contain 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.

[0098] R a01 , R a4 and R a5 is the R in formula (a2-A). a2 The same can be mentioned. R a01 , R a4 and R a5 is preferably a hydrogen atom or a methyl group, 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 , R a04 , 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. Ra02 , 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 the formula (I) 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 , R a6 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, ethyl group, phenyl group or naphthyl group which may have a halogen atom. R a04is 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, ethyl group, cyclohexyl group or 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.

[0099] Examples of the structural unit (a1-0) include structural units 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, and 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. TIFF2026026040000110.tif120161

[0100] Examples of the structural unit (a1-1) include structural units derived from monomers described in JP-A-2010-204646. Among these, structural units represented by any one of formulas (a1-1-1) to (a1-1-7) and R in the structural unit (a1-1) are preferred.a4 A structural unit in which the methyl group corresponding to the formula (a1-1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group is preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. TIFF2026026040000111.tif34168

[0101] 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 the methyl group corresponding to the formula (a1-2-2), (a1-2-5), (a1-2-6), and (a1-2-10) to (a1-2-20) are substituted with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. TIFF2026026040000112.tif92163

[0102] When the resin (A) 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 structural units, based on the total structural units of the resin (A), can be 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. Also, the total content can be 95 mol% or less, 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, the total content can be 10 to 95 mol%, 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) contains the structural unit (a1-0), the content thereof, based on the total structural units of the resin (A), can be 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, even more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, and still more preferably 35 mol% or more. It can also be 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less, and still more preferably 60 mol% or less. Specifically, it can be 5 to 80 mol%, preferably 5 to 75 mol%, more preferably 10 to 70 mol%, even more preferably 10 to 65 mol%, and still more preferably 10 to 60 mol%. When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these structural units, based on the total structural units of the resin (A), can be 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. Also, the total content can be 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 65 mol% or less. Specifically, the total content can be 10 to 90 mol%, 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%.

[0103] An example of the structural unit (a1) having the group (2) is a structural unit represented by formula (a1-4) (hereinafter, sometimes referred to as "structural unit (a1-4)"). TIFF2026026040000113.tif31119[In formula (a1-4), Ra1 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 -CH2- contained in the alkanediyl group 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 a carbonyl group. 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, together with the -CO- to which they are bonded, a divalent hydrocarbon group having 2 to 20 carbon atoms, and the hydrocarbon group and the -CH2- contained in the divalent hydrocarbon group may be replaced with -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 from each other. 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 between 0 and 2.

[0104] R a1 and R a17Examples of the halogen atom and the alkyl group optionally having a halogen atom in formula (a2-A) include R a2 and R in formula (a1-0) a01 The same examples as those given above are included. 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 even more preferably a hydrogen atom or a methyl group. R a17 is the R in formula (a2-A). a27 Examples include the same as those exemplified above. 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.

[0105] A a11 and R a18 is A in equation (a2-A). a21 and R a28 Examples include the same as those exemplified above. A a11 -CH2- in the alkanediyl group is -O-, -CO- or -NR a18 Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, and *-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 Aa12 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, within the limits of the upper limit of the carbon number, a11 Examples of the alkanediyl groups include the same alkanediyl groups as those shown in the 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 even more preferably 0 or 1. mc is preferably 0 or 1. R a34 , R a35 and R a36 Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which these groups are combined. 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 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): TIFF2026026040000114.tif10151 Examples of aromatic hydrocarbon groups 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 (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl 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. In particular, R a36 Examples of the 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. R a35 and R a36 Examples of the divalent cyclic hydrocarbon group having 2 to 20 carbon atoms that are 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 TIFF2026026040000115.tif16105R 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 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.

[0106] -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. a11 When the bonding position of A is the 2nd position, it may be bonded to any of the 1st position and the 3rd to 8th positions. a11 When the bonding position of A is position 1, at least one of A is preferably bonded to position 3 to 6, and more preferably bonded to position 3 or 4. a11 When the bonding position is the 2nd position, it is preferably bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0107] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferred are structural units represented by formulas (a1-4-1) to (a1-4-42) and R in the structural unit (a1-4). 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). TIFF2026026040000116.tif229165

[0108] When the resin (A) contains the structural unit (a1-4), the content thereof, based on the total of all structural units in the resin (A), can be 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. The content can also be 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 65 mol% or less. Specifically, the content 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 particularly preferably 20 to 60 mol%.

[0109] Examples of the structural unit derived from a (meth)acrylic monomer having the group (2) include a structural unit represented by formula (a1-5) (hereinafter, sometimes referred to as "structural unit (a1-5)"). TIFF2026026040000117.tif4558[In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, 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 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. R in formula (a1-5) a8 Examples of the halogen atom and the alkyl group optionally having a halogen atom in formula (a1-0) include R a01 The same examples as those given above are included. 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 Among these, it is preferred that one is —O— and the other is —S—. s1 is preferably 1. s1' is preferably an integer of 0 to 2. Z a1 is preferably a single bond or —CH2—CO—O—.

[0110] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP-A-2010-61117. Among these, the structural units represented by formulas (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. When the resin (A) contains the structural unit (a1-5), the content thereof, based on the total structural units of the resin (A), 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. It may also be 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, it 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%.

[0111] An example of the structural unit (a1) having the group (1) is a structural unit represented by formula (a1-6) (hereinafter, sometimes referred to as "structural unit (a1-6)"). TIFF2026026040000119.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 a65 -*, * represents the bonding site with -Ar, R a65 represents a hydrogen atom or an alkyl group having 1 to 6 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.]

[0112] R in formula (a1-6) a61 Examples of the halogen atom and the alkyl group optionally having a halogen atom in formula (a1-0) include R a01 The same examples as those given above are included. R a61 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. R a62 , R a63 , R a64 and R a65 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 even more 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 monocyclic alicyclic hydrocarbon groups include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of polycyclic alicyclic hydrocarbon groups 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 together include an adamantane ring, a cyclopentane ring, and a cyclohexane ring. a62 and R a63 -C(R a62 )(R a63 )(R a64 ) includes the following groups. * represents the bonding site with the oxygen atom. The number of carbon atoms in the ring is preferably 3 to 16, and more preferably 3 to 12. TIFF2026026040000120.tif34110

[0113] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms in the formula 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 are each preferably 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, an o-methylphenylene group, an m-methylphenylene group, a p-methylphenylene group, a p-ethylphenylene group, a p-tert-butylphenylene 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. These groups are represented by R a27 Examples include the same as those exemplified above. 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.

[0114] Examples of the structural unit (a1-6) include structural units represented by formulas (a1-6-1) to (a1-6-44), preferably structural units represented by formulas (a1-6-1) to (a1-6-9), and (a1-6-37) to (a1-6-44), more preferably structural units represented by formulas (a1-6-1), (a1-6-2), (a1-6-4), (a1-6-5), (a1-6-7), (a1-6-8), and (a1-6-37) to (a1-6-44), and even more preferably structural units represented by formulas (a1-6-7), (a1-6-8), and (a1-6-37) to (a1-6-44). a61 In the structural units shown below, the hydrogen atom corresponding to R is replaced by a methyl group or the like. a61 The structural unit (a1-6) also includes a structural unit in which the methyl group corresponding to the following is replaced with a hydrogen atom or the like. TIFF2026026040000121.tif227165

[0115] When the resin (A) contains the structural unit (a1-6), the content thereof, based on the total structural units of the resin (A), can be 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, even more preferably 10 mol% or more, still more preferably 20 mol% or more, even more preferably 30 mol% or more, and even more preferably 40 mol% or more. Also, the content can be 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 60 mol%.

[0116] Further, examples of the structural unit (a1) include the following structural units. TIFF2026026040000122.tif33167

[0117] When resin (A) contains structural units represented by formulae (a1-7-1) to (a1-7-7), the content of these structural units relative to the total structural units of resin (A) is typically 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. Also, the content may be 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, the content 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 particularly preferably 20 to 60 mol%.

[0118] Further, examples of the structural unit (a1) include the following structural units. When resin (A) contains structural units represented by formulas (a1-8-1) to (a1-8-3), the content thereof, based on the total structural units of resin (A), can be 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. Also, the content can be 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, 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 %.

[0119] <Structural unit(s)> The structural unit (s) is derived from a monomer (hereinafter sometimes referred to as "monomer (s)") that does not have an acid labile group. As the monomer from which the structural unit (s) is derived, a monomer that does not have an 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. The resist composition of the present invention may contain a resin containing a structural unit having a hydroxy group or a carboxy group but no acid labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring but no acid labile group (hereinafter sometimes referred to as "structural unit (a3)"), thereby improving the resolution of the resist pattern and adhesion to the substrate. In addition to the structural units described above, structural units (s) may also include structural units having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), structural units having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"), structural units having a sultone structure (hereinafter sometimes referred to as "structural unit (a6)"), structural units that decompose upon exposure to generate acid (hereinafter sometimes referred to as "structural unit (a7)"), and other structural units known in the art.

[0120] <Structural unit (a2)> The structural unit (a2) is a structural unit represented by formula (a2) excluding the structural unit (a2-A), and has an alcoholic hydroxy group, a phenolic hydroxy group, or a carboxy group. TIFF2026026040000124.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 with 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, and the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not -O-, -CO-, -S-, -SO-, or -NR a28 It may be replaced by - or -SO2-. L a22 represents a single bond or a chain hydrocarbon group of 1 to 12 carbon atoms which may have a fluorine atom, and -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-. na2 represents an integer of 1 to 5. When na2 is 2 or more, a plurality of L a22 may be the same or different from each other. R a2 and A a21 Examples of the compound include those exemplified in formula (a2-A). 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 even more preferably a hydrogen atom or a methyl group.

[0121] A a21 -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, and *-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, within the limits of the upper limit of the carbon number, a21Examples of the alkanediyl groups include the same alkanediyl groups as those shown in the 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.

[0122] L a21 The hydrocarbon group in is a (na2+1)-valent hydrocarbon group, and examples thereof include linear or branched chain hydrocarbon groups, monocyclic or polycyclic (including spiro rings, fused rings, or bridged rings) alicyclic hydrocarbon groups, and cyclic hydrocarbon groups such as aromatic hydrocarbon groups, and may also be a group 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 alkanpentyl group, and an alkanehexyl group. Examples of the alkanediyl group include A a21 Examples of the alkanediyl groups include the same alkanediyl groups as those shown in the 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 decantriyl 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 alkanpentyl group include a methanepentyl group, an ethanepentyl group, a propanepentyl group, a butanepentyl group, a pentanepentyl group, and a hexanepentyl 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, still 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 above formula include the following alicyclic hydrocarbon groups: The binding site can be at any position. TIFF2026026040000125.tif46168 Examples include divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkanepentyl group, and a cycloalkanehexyl group. 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, even more preferably 3 to 16 carbon atoms, even more preferably 3 to 12 carbon atoms, still more preferably 6 to 12 carbon atoms, and particularly preferably 6 to 10 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 arenetetrayl group, an arenetyl group, and an arenehexyl group. Specific examples 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, even more preferably 6 to 14 carbon atoms, still more preferably 6 to 12 carbon atoms, and even more preferably 6 to 10 carbon atoms. Examples of the group combining two or more types include a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group, a group combining an aromatic hydrocarbon group with a chain hydrocarbon group, a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group and 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 A a21 and L a22 may be bound to L a21 The alkanediyl group may be substituted with -O- or -CO-, etc., and L a21 When 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, and X a21 represents -O-, -O-CO-, -CO-O- or -O-CO-O-, * represents X a2 It is preferable that the bond is The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR a28Examples of the group substituted with - or -CO- 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 thiol group (a group in which -CH2- in a methyl group is replaced with -S-), an amino group (a group in which -CH2- in a methyl group is replaced with -NR a28 -), oxy group (a group in which -CH2- in a methylene group is replaced with -O-), carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), thio group (a group in which -CH2- in a methylene group is replaced with -S-), sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), peptide group (a group in which -CH2-CH2- in an ethylene group is replaced with -CO-NR a28 -), alkoxy group (a group in which -CH2- at any position in the alkyl group is replaced with -O-), alkylthio group (a group in which -CH2- at any position in the alkyl group is replaced with -S-), alkoxycarbonyl group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -O-CO-), alkylsulfonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -SO2-), 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 a28 -), alkyl peptide group (wherein -CH2-CH2- at any position in the alkyl group is replaced by -CO-NR 28-), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -CO-O-), alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position in an alkyl group is replaced with -O-CO-O-), alkoxyalkoxy group (a group in which two -CH2- at any position in an alkyl group are replaced with -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 (an alkanediyl group in which -CH2-CH2- at any position in an alkanediyl group is replaced with -O-CO-), 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 alkanediyloxycarbonyloxy group (an alkanediyl group in which -CH2-CH2-CH2- at any position is replaced with -O-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-), an alkanediylamino group (an alkanediyl group in which -CH2- at any position is replaced with -NR a28 -), alkanediyl peptide group (wherein any -CH2-CH2- at any position in the alkanediyl group is replaced by -CO-NR a28 Examples of such groups include a group substituted with -, a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group combining two or more of these groups. Also included are groups in which one or more hydrogen atoms of these groups have been replaced with a bonding site. Examples of such substituted groups include those similar to the groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0123] In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be -O-, -S-, -CO-, -SO-, -NR a28 As the group substituted with - or -SO2-, the same groups as those exemplified in this specification can be mentioned, within the range permitted by the upper limit of the number of carbon atoms. 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) may have a halogen atom as a substituent, thereby substantially having a substituent such as a haloalkyl group. Examples of the haloalkyl group include alkyl fluoride, alkyl chloride, alkyl bromide, and alkyl iodide, such as a chloromethyl group, bromomethyl group, iodomethyl group, fluoromethyl group, difluoromethyl group, trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, and 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 a21 can 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, even more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. La21 The -CH2- contained in the hydrocarbon group is -O-, -S-, -CO-, -SO-, -NR a28 - or -SO2-, L a21 can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, a thiol group, an alkylthio group, an alkylsulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an alkoxycarbonyloxy group, an amino group, an alkylamino group, an alkylpeptide group, an acryloyloxy group, or a methacryloyloxy group. Examples of the above groups include the same groups as those exemplified in this specification. L a21 The substituents that 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 (wherein —CH— 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 (wherein —CH— 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, 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 When the alkanediyl group is replaced by -O- or -CO-, etc., for example, *-L a23 -X a21 -(L a23 represents an alkanediyl group having 1 to 8 carbon atoms, and X a21 represents -O-, -O-CO-, -CO-O- or -O-CO-O-, * represents A a21 It is also preferred that the bond is L a21 represents a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (provided that -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO-, -NR a28 - or -SO2-) or a group formed by combining a chain hydrocarbon group of 1 to 8 carbon atoms which may have a substituent with a cyclic hydrocarbon group of 3 to 20 carbon atoms which may have a substituent (wherein -CH2- in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR a28 - or -CO-), and examples thereof include an optionally substituted chain hydrocarbon group having 1 to 10 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO-, -NR a28 - or -SO2-) or a group formed by combining a chain hydrocarbon group of 1 to 6 carbon atoms which may have a substituent with a cyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent (provided that -CH2- in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR a28 - or -CO- may be substituted.) is more preferred.

[0124] L a22Examples of the chain hydrocarbon group having 1 to 12 carbon atoms 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. 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. 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. L a22 may have one or more fluorine atoms. L a22 The -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and these substituted groups may be in the range of L, as long as the upper limit of the number of carbon atoms allows. a21 Examples include the same as those exemplified above. na2 is preferably an integer of 1 to 4, and more preferably an integer of 1 to 3. L a21 When R is a single bond or a chain hydrocarbon group, examples of the structural unit (a2) include the following structural units: a2 A structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom or the like is also a suitable structural unit of the structural unit (a2), similar to the structural units shown below. TIFF2026026040000126.tif67168

[0125] When producing a resist pattern from the resist composition of the present invention, if a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet) is used as an exposure light source, the structural unit (a2) preferably has a phenolic hydroxy group, and more preferably the structural unit (a2-A) described below. Furthermore, if an ArF excimer laser (193 nm) or the like is used, the structural unit (a2) preferably has an alcoholic hydroxy group, and more preferably the structural unit (a2-C) described below. The structural unit (a2) may contain one type alone or two or more types.

[0126] 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)"). TIFF2026026040000127.tif46100[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—, and k2 represents an integer of 1 to 7. * represents the 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, a plurality of R a27 may be the same or different from each other. L a25 is preferably —O— or —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 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. 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 even more preferably 0 or 1. nC22 is preferably an integer of 0 to 6, more preferably an integer of 0 to 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1.

[0127] 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 in the following structural units: a2 In particular, structural units represented by any one of formulas (a2-B-1) to (a2-B-5) and formulas (a2-C-1) to (a2-C-9) are preferred. When the resin (A) contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof, based on the total structural units of the resin (A), is 1 mol% or more, preferably 2 mol% or more. Alternatively, the content may be 45 mol% or less, 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, the content may be 1 to 45 mol%, 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%.

[0128] TIFF2026026040000129.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 greater, the groups in the parentheses may be the same or different. nD22 represents an integer of 0 to 4. When nD22 is 2 or more, a plurality of Ra27 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 aryl group, a trifluoromethyl group is preferred. 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 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. 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, even more preferably 0 or 1, and even more preferably 0.

[0129] 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)"). TIFF2026026040000130.tif51107[In formula (a2-D1), R a2 , A a21 , R a27 , nD2 and nD22 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.

[0130] Examples of the structural unit (a2-D) include the structural units shown below. TIFF2026026040000131.tif61168

[0131] In the structural units represented by formulae (a2-D-1) to (a2-D-8), R a2 In the structural units represented by formulas (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, structural units represented by formulas (a2-D-1) to (a2-D-8) are preferred, structural units represented by formulas (a2-D-1) to (a2-D-4) are more preferred, and structural units represented by formula (a2-D-1) are even more preferred.

[0132] When the resin contains the structural unit (a2-D), its content 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. It is also 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%.

[0133] <Structural unit (a3)> The lactone ring contained in 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 a condensed ring of a monocyclic lactone ring with 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)). 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 may be contained. TIFF2026026040000132.tif51164 [In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and L a6 are each independently -O- or -O-(CH2) k3 It represents a group represented by —CO—O— (k3 represents an integer 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 a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. Ra22 , 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 as or different from each other.

[0134] R a21 , R a22 , R a23 and R a25 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 and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 , R a5 Examples include the same as those exemplified above. 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.

[0135] L a4 ~La6 are each independently preferably -O- or -O-(CH2) k3 In -CO-O-, k3 is a group in which k3 is any integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and further preferably an oxygen atom. L a7 is preferably -O- or *-OL a8 It is —CO—O—, and more preferably —O—, —O—CH 2 —CO—O— or —O—C 2 H 4 —CO—O—. R a18 , R a19 , R a20 and 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 a21 is preferably a methyl group. R a22 , R a23 and R a25 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.

[0136] 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'). TIFF2026026040000133.tif2956(in the formula, R a24 , L a7 has the same meaning as above.)

[0137] 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 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 units, 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 is replaced with a hydrogen atom is preferred. When the resin contains the structural unit (a3), the total content thereof, based on all structural units in the resin, is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more. It may also be 70 mol% or less, 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, it may be 1 to 70 mol%, 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%. Furthermore, 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, still more preferably 40 mol% or less, even more preferably 30 mol% or less, still 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%.

[0138] <Structural unit (a4)> The structural unit represented by formula (a4) is shown below. TIFF2026026040000135.tif3654[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents an aliphatic hydrocarbon group having 1 to 48 carbon atoms and containing a halogen atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-.]

[0139] R 42 Examples of the aliphatic hydrocarbon group represented by the formula (I) include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups. Examples of the chain hydrocarbon group include linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups, and branched alkyl groups such as isopropyl and isobutyl groups. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include monocyclic alicyclic 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 hydrocarbon groups which are polycyclic cycloalkyl groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* indicates a bonding site): TIFF2026026040000136.tif10146 Examples of groups formed by combination include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic hydrocarbon groups, such as -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic 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; 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. The terminal of the branched alkanediyl group may be a methyl group. R 42 Examples of the halogen atom contained in the aliphatic hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 42 Examples of the aliphatic hydrocarbon group in which -CH- is replaced with -O- or -CO- include a hydroxy group, a carboxy group, a carbonyl group, an oxy 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, a cycloalkoxy group, a cycloalkylalkoxy group, and a group combining two or more of these groups. These substituted groups include the same groups as exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0140] The structural unit (a4) is R 42 is preferably an aliphatic hydrocarbon group having a fluorine atom, and R 42 However, examples of the structural unit (a4) that is an aliphatic 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)"), a structural unit represented by formula (a4-3) (hereinafter, may be referred to as "structural unit (a4-3)"), and a structural unit represented by formula (a4-A) (hereinafter, may be referred to as "structural unit (a4-A)"). The structural unit represented by formula (a4-1) is a structural unit shown below. TIFF2026026040000137.tif3092[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.

[0141] 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 42fExamples of the alkanediyl group having a fluorine atom in the formula (I) include a linear alkanediyl group 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 42fThe number of fluorine atoms contained in the alkanediyl group and cycloalkanediyl group having a fluorine atom in the formula (I) 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 formula (I) are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0142] L 42f Examples 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.

[0143] 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 42fis 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.

[0144] The structural unit (a4-1) includes the structural units shown below and R in the structural unit (a4-1) in the structural units shown below. 41 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026026040000138.tif55168The structural unit represented by formula (a4-2) is the structural unit shown below. TIFF2026026040000139.tif33102[In formula (a4-2), R 41 represents a hydrogen atom or a methyl group. L 43f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. R 43f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. However, L 43f and R 43f At least one of L has a fluorine atom, 43f and R 43f The maximum total number of carbon atoms is 21.

[0145] L 43f and R 43f Examples of the aliphatic hydrocarbon group in L include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups. 43f and R 43f Examples of the aliphatic hydrocarbon group in 43f and R 43fAs long as the upper limit of the total number of carbon atoms in 42 Examples of the aliphatic hydrocarbon group include the same groups as the exemplified aliphatic hydrocarbon groups.

[0146] L 43f The aliphatic hydrocarbon group is preferably an alkanediyl group having 1 to 6 carbon atoms or a group represented by formula (L43f-1). TIFF2026026040000140.tif13119 [In formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represents a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may contain a fluorine atom. L 47f represents a single bond or a divalent aliphatic 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, and ** is -O-CO-R 43f ]

[0147] L in the group represented by formula (L43f-1) 45f , L 46f and L 47fExamples of the divalent aliphatic hydrocarbon group represented by include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic hydrocarbon group, and a divalent aliphatic hydrocarbon group formed by combining an alkanediyl group with a divalent alicyclic hydrocarbon group. 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, and a 2-methylpropane-1,2-diyl group. Preferably, s is 0.

[0148] 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 TIFF2026026040000141.tif47140

[0149] R 43f is preferably an aliphatic 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). TIFF2026026040000142.tif41157 [In formula (a4-2A) and formula (a4-2B), R 41 and L 43f represents the same as in formula (a4-2). R 43fA represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms and containing a fluorine atom. A 43f represents a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. X 43 represents **-O-CO- or **-CO-O-, and ** represents A 43f represents the binding site with R 43fBrepresents an aliphatic 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 aliphatic hydrocarbon group of R 42 Examples of the aliphatic hydrocarbon groups include the same aliphatic hydrocarbon groups as those exemplified 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, and *-(CF2) n43f -R 42’ (* represents the bonding site with the carbonyl group. n43f represents an integer of 1 to 6. R 42’ represents a hydrogen atom or a fluorine atom.) or a perfluorocycloalkyl group having 3 to 12 carbon atoms is more preferred. A 43f and R 43fB The aliphatic hydrocarbon group of R in formula (a4) is as long as the upper limit of the number of carbon atoms permits. 42 Examples of the aliphatic hydrocarbon groups include the same aliphatic hydrocarbon groups as those exemplified above. A 43f is preferably a divalent chain hydrocarbon group which may have a fluorine atom, a divalent alicyclic hydrocarbon group, or a combination thereof, more preferably a divalent chain hydrocarbon group which has a fluorine atom, and even more preferably a fluorinated alkanediyl group having 1 to 6 carbon atoms. R 43fBThe aliphatic hydrocarbon group which may have a fluorine atom is preferably a chain hydrocarbon group which may have a fluorine atom, an alicyclic 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-octafluoropropyl group, a ... More preferred are fluorinated alkyl groups such as nonafluorobutyl, butyl, perfluoropentyl, 2,2,3,3,4,4,5,5,5-nonafluoropentyl, pentyl, hexyl, perfluorohexyl, heptyl, perfluoroheptyl, octyl, and perfluorooctyl groups, cyclopropylmethyl, cyclopropyl, cyclobutylmethyl, cyclopentyl, cyclohexyl, perfluorocyclohexyl, adamantyl, adamantylmethyl, adamantyldimethyl, norbornyl, norbornylmethyl, perfluoroadamantyl, and perfluoroadamantylmethyl groups.

[0150] In formula (a4-2B), *-A 43f -X 43 -R 43fB 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). TIFF2026026040000143.tif15170

[0151] 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 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026026040000144.tif99167

[0152] 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 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026026040000145.tif111163

[0153] The structural unit (a4) also includes a structural unit represented by formula (a4-3). TIFF2026026040000146.tif3689[In formula (a4-3), R 41 represents a hydrogen atom or a methyl group. L 44f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. R 44f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. However, L 44f and R 44f At least one of L has a fluorine atom, 44f and R 44f The maximum total number of carbon atoms is 21.

[0154] L 44f and R 44f Examples of the aliphatic hydrocarbon group in L include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups. 44f and R 44f Examples of the aliphatic hydrocarbon group in 44f and R 44f As long as the upper limit of the total number of carbon atoms in 42 Examples of the aliphatic hydrocarbon group include the same groups as the exemplified aliphatic hydrocarbon groups. L 44fis 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 - (j1 to j5 each independently represent an integer of 1 to 6). Also preferred is an alkanediyl group having 1 to 4 carbon atoms (one -CH2- contained in the alkanediyl group may be replaced with -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced with -CO-O- or -O-CO-). R 44f is preferably an aliphatic 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 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.

[0155] Examples of the structural unit represented by formula (a4-3) include the following structural units and structural units represented by the following formulas: 41 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026026040000147.tif86170

[0156] The structural unit (a4) also includes a structural unit represented by formula (a4-A). TIFF2026026040000148.tif3673[In formula (a4-A), R 44 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X 44 represents a single bond or *-CO-O-. * represents R44 represents the bonding site with the carbon atom to which it is bonded. L 44 represents an aliphatic hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO- or -CO-. R 45 represents a fluorinated alkyl group having 1 to 8 carbon atoms. R 46 represents a hydrogen atom or a fluorinated alkyl group having 1 to 6 carbon atoms, and the fluorinated alkyl group is L 44 may bond to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-. mi represents an integer of 1 to 4. When mi is 2 or more, the groups in the parentheses may be the same or different.]

[0157] R 44 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 and R a5 Examples include the same as those exemplified above. R 44 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, further preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0158] L 44 Examples of the aliphatic hydrocarbon group in include chain hydrocarbon groups and monocyclic or polycyclic (including spiro rings, fused rings, bridged rings, etc.) alicyclic hydrocarbon groups, and may also be groups that combine two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group). Examples of the chain hydrocarbon group include divalent to pentavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, and an alkanpentyl 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, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, and heptadecane-1,17-diyl groups; Examples of branched alkanediyl groups include an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-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. 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, still more preferably 1 to 6, even more preferably 1 to 5, and particularly preferably 1 to 4.

[0159] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups: The binding site can be any position. TIFF2026026040000149.tif45164 Examples include divalent to pentavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, and a cycloalkanepentyl group. 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, and the like; Examples include cycloalkanediyl groups such as 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, spirocyclohexane-1,2'-cyclopentane-diyl group, and spiroadamantane-2,3'-cyclopentane-diyl group; and polycyclic alicyclic hydrocarbon groups such as spiro rings having cycloalkanediyl groups bonded to norbornanediyl groups or adamantanediyl groups via spiro bonds. 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, even more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms.

[0160] Examples of groups that combine two or more types include groups that combine an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups and chain hydrocarbon groups may be combined. In addition, when any of the groups is X 44 may be bound to Examples of groups combining an alicyclic hydrocarbon group and a chain hydrocarbon group include a group in which an alicyclic hydrocarbon group is bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-, etc.), a group in which a chain hydrocarbon group is bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), a group in which a chain hydrocarbon group and an alicyclic hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), Examples of such a group include a group having a hydrocarbon group bonded thereto (for example, *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-, etc.), a group having an alicyclic hydrocarbon group, a chain hydrocarbon group, and an alicyclic hydrocarbon group bonded to a chain hydrocarbon group (for example, *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-, etc.), and a group having an alicyclic hydrocarbon group, a chain hydrocarbon group, and a chain hydrocarbon group bonded to an alicyclic hydrocarbon group (for example, *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.). * is X 44 represents the binding site with Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites.

[0161] L 44 -CH2- contained in the aliphatic hydrocarbon group having 1 to 28 carbon atoms may be replaced by -O-, -S-, -SO-, -SO2- or -CO-. L 44 When one or more —CH2— groups in the aliphatic hydrocarbon group having 1 to 28 carbon atoms are replaced with —O—, —S—, —SO—, —SO2—, or —CO—, the number of carbon atoms before the replacement is defined as the number of carbon atoms in the aliphatic hydrocarbon group. Examples of groups in which -CH- in an aliphatic hydrocarbon group is replaced with -O-, -S-, -SO-, -SO-, or -CO- include a hydroxy group, a carboxy group, a thiol group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, and groups in which two or more of these groups are combined. Examples of these substituted groups include the same groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. Examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced by -O-, -S-, -SO-, -CO- or -SO2- include the same groups as exemplified in this specification, within the upper limit of the number of carbon atoms permitted.

[0162] L 44 The aliphatic hydrocarbon group in may have one or more substituents, such as a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms (wherein -CH2- in the alkyl group or the alicyclic hydrocarbon group may be replaced by -O- or -CO-). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of haloalkyl groups having 1 to 4 carbon atoms include fluorinated alkyl groups having 1 to 4 carbon atoms, chlorinated alkyl groups having 1 to 4 carbon atoms, brominated alkyl groups having 1 to 4 carbon atoms, and iodinated alkyl groups having 1 to 4 carbon atoms. Examples of haloalkyl groups include perfluoroalkyl groups having 1 to 4 carbon atoms (such as trifluoromethyl, pentafluoroethyl, heptafluoropropyl, and nonafluorobutyl), 2,2,2-trifluoroethyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 3,3,4,4,4-pentafluorobutyl, chloromethyl, bromomethyl, and iodomethyl. The number of carbon atoms in the haloalkyl group is preferably 1 to 3, and more preferably 1 or 2. Examples of the alkyl group having 1 to 12 carbon atoms include 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 nonyl group, a decyl group, an undecyl group, a dodecyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 9, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alicyclic hydrocarbon group having 3 to 18 carbon atoms include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and cyclodecyl, and polycyclic cycloalkyl groups such as decahydronaphthyl, adamantyl, and norbornyl. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12, and even more preferably 3 to 10. Examples of aromatic hydrocarbon groups having 6 to 18 carbon atoms 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 14, more preferably 6 to 12, and even more preferably 6 to 10. When -CH2- in an alkyl group is replaced with -O- or -CO-, the number of carbon atoms before the replacement is counted as the total number of carbon atoms in the alkyl group. Examples of the substituted group include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, and an alkoxycarbonyloxy group. These substituted groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the carbon number. The number of carbon atoms in the alkoxy 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 number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 9, 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 10, 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 alkylcarbonyloxy group is preferably 2 to 9, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Furthermore, examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced with -O- 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. L 44 The substituent that the aliphatic hydrocarbon group in the formula (I) may have is preferably a halogen atom, a haloalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms (-CH2- contained in the alkyl group or the alicyclic hydrocarbon group may be replaced with -O- or -CO-), more preferably a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 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-), and even more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group. L 44 is R 46When the fluorinated alkyl group does not form an alicyclic hydrocarbon group with the fluorinated alkyl group, the alicyclic hydrocarbon group is a chain hydrocarbon group of 1 to 12 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 of 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), or a chain hydrocarbon group of 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent. and a group formed by combining a hydrocarbon group with a hydroxyl group (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-, and -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O- or -CO-), and examples thereof include a chain hydrocarbon group having 1 to 8 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 12 carbon atoms which may have a substituent, or a group formed by combining a hydrocarbon group with a hydroxyl group with a hydroxyl group (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-). It is more preferably a group formed by combining a chain hydrocarbon group of 1 to 6 carbon atoms with an alicyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and examples thereof include a chain hydrocarbon group of 1 to 8 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 of 5 to 12 carbon atoms which may have a substituent, a chain hydrocarbon group of 1 to 6 carbon atoms and More preferably, it is a group formed by combining an alicyclic hydrocarbon group of 5 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), or a group formed by combining an alicyclic hydrocarbon group of 5 to 12 carbon atoms which may have a substituent, a chain hydrocarbon group of 1 to 6 carbon atoms, and an alicyclic hydrocarbon group of 5 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-).

[0163] R 45Examples of the fluorinated alkyl group having 1 to 8 carbon atoms in the formula (I) include a difluoromethyl group, a trifluoromethyl group, a 1,1-difluoroethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a perfluoroethyl group, a 1,1,2,2-tetrafluoropropyl group, a 1,1,2,2,3,3-hexafluoropropyl group, a perfluoroethylmethyl group, a 1-(trifluoromethyl)-1,2,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 1,1,2,2-tetrafluorobutyl group, a 1,1,2,2,3,3-hexafluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluorobutyl group, a 1,1-bis(trifluoro)methyl group, a Examples of the fluorinated alkyl group include 2,2,2-trifluoroethyl, 2-(perfluoropropyl)ethyl, 1,1,2,2,3,3,4,4-octafluoropentyl, perfluoropentyl, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl, perfluoropentyl, 2-(perfluorobutyl)ethyl, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl, perfluoropentylmethyl, perfluorohexyl, perfluoroheptyl, and perfluorooctyl. The number of carbon atoms in the fluorinated alkyl group is preferably 1 to 6, more preferably 1 to 5, even more preferably 1 to 4, and even more preferably 1 to 3. R 46 The fluorinated alkyl group having 1 to 6 carbon atoms in R is as large as possible within the upper limit of the carbon number. 45 The same fluorinated alkyl groups having 1 to 6 carbon atoms as those given as examples of the fluorinated alkyl groups in the above can also be used. R 45 is R 46 When is a fluorinated alkyl group having 1 to 6 carbon atoms, it is preferably a fluorinated alkyl group having 1 to 6 carbon atoms, more preferably a fluorinated alkyl group having 1 to 3 carbon atoms, still more preferably a trifluoromethyl group, a perfluoroethyl group or a perfluoropropyl group, and even more preferably a trifluoromethyl group. R45 is R 46 When is a hydrogen atom, it is preferably a fluorinated alkyl group having 1 to 6 carbon atoms, more preferably a fluorinated alkyl group having 1 to 5 carbon atoms, and even more preferably a fluorinated alkyl group having 3 to 5 carbon atoms. R 46 L 44 When R is bonded to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, 46 L 44 Examples of groups formed by bonding with include groups represented by the following formulae: In the following formulae, * and ** represent bonding sites, and one of the two ** represents a bonding site with a hydroxy group and the other represents a bonding site with R 45 represents the binding site with L 44A L 44 R is a part of the hydrocarbon group and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. 46 L 44 The alicyclic hydrocarbon group formed by bonding with the above preferably has 3 to 10 carbon atoms, more preferably 3 to 8 carbon atoms, and even more preferably 3 to 6 carbon atoms. TIFF2026026040000150.tif22138R 46 is preferably a hydrogen atom or a fluorinated alkyl group having 1 to 3 carbon atoms. mi is preferably an integer of 1 to 3, more preferably 1 or 2, and even more preferably 1.

[0164] Examples of the structural unit (a4-A) include the following structural units. In the following structural units, R 44 and structural units in which the methyl group corresponding to R is replaced by a hydrogen atom, a halogen atom, a haloalkyl group, or an alkyl group other than a methyl group. 44 Specific examples of the structural unit (a4-A) include structural units in which the hydrogen atom corresponding to the following is replaced with a halogen atom, a haloalkyl group, or an alkyl group. When the resin contains the structural unit (a4), the content thereof is preferably from 1 to 20 mol %, more preferably from 2 to 15 mol %, and even more preferably from 3 to 10 mol %, based on all structural units in the resin.

[0165] <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, and among these, the structural unit (a5) is preferably a group containing an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by formula (a5-1). TIFF2026026040000152.tif3971[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-.]

[0166] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Examples of polycyclic alicyclic hydrocarbon groups include adamantyl and norbornyl. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. R 52is 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 The divalent saturated hydrocarbon group in the formula (I) includes a divalent saturated chain hydrocarbon group and a divalent saturated alicyclic hydrocarbon group, and is preferably a divalent saturated chain hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include a methylene group, an ethylene group, and an alkanediyl group such as 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) in which one -CH2- is replaced with -O- or -CO- include groups represented by formula (L1-1) to formula (L1-4). In the following formulae, * and ** each represent a bonding site, and * represents a bonding site to an oxygen atom. TIFF2026026040000153.tif18165[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents L x1 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 x3 represents 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, 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 x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7is 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, 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, 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, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0167] Examples of the group represented by formula (L1-1) include the divalent groups shown below. TIFF2026026040000154.tif36147 Examples of the group represented by formula (L1-2) include the divalent groups shown below. TIFF2026026040000155.tif23130 Examples of the group represented by formula (L1-3) include the divalent groups shown below. TIFF2026026040000156.tif16147 Examples of the group represented by formula (L1-4) include the divalent groups shown below. TIFF2026026040000157.tif13168L 55 is preferably a single bond or a group represented by formula (L1-1).

[0168] The structural unit (a5-1) includes the structural units shown below and R in the structural unit (a5-1) in the structural units shown below. 51 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. When the resin 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.

[0169] <Structural unit (a6)> The structural unit (a6) is a structural unit having an -SO2- group, and preferably has an -SO2- group in a side chain. The structural unit having an -SO2- group may have a linear structure having an -SO2- group, a branched structure having an -SO2- group, or a cyclic structure (monocyclic or polycyclic structure) having an -SO2- group. A structural unit having a cyclic structure having an -SO2- group is preferred, and a structural unit having a cyclic structure containing an -SO2-O- group (sultone ring) is more preferred.

[0170] The sultone ring may be a ring having 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 —SO—O—. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom, and an oxygen atom is preferred. TIFF2026026040000159.tif2877

[0171] The sultone ring may have a substituent, and 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.

[0172] Halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, 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 gro...

Claims

1. An acid generator containing a salt represented by formula (I): [In formula (I), m10 represents an integer of 1 to 3, and when m10 is 2 or greater, the groups in the parentheses may be the same or different. m11 represents an integer of 0 to 2, and satisfies 2≦m10+m11≦3; when m10+m11=2, X represents an iodine atom; when m10+m11=3, X represents a sulfur atom; and when m11 is 2 or greater, the groups in parentheses may be the same as or different from each other. A １ and A ２ each independently represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a substituent. ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ It may be replaced by - or -CO-. R １１ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ar １ and Ar ２ each independently represents an aromatic hydrocarbon group having 6 to 10 carbon atoms or a heterocyclic hydrocarbon group having 4 to 9 carbon atoms, and the aromatic hydrocarbon group and the heterocyclic hydrocarbon group may have a substituent. R １ and R ４ are each independently a hydroxy group, *-X １ -R １０ or *-X ２ -L １１ -X １ -R １０ Represents. X １ and X ２ each independently represents —CO—O—, —O—CO—, —O—CO—O— or —O—. * indicates Ar １ or Ar ２ represents the binding site with L １１ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ It may be replaced by - or -CO-. R １０ represents an acid labile group. R ２ and R ３ each independently represents a halogen atom or a hydrocarbon group having 1 to 28 carbon atoms, and the hydrocarbon group may have a substituent. ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ - or -CO-, and two R ２ , two R ３ or R ２ and R ３ is bonded, and X ＋ may form a ring containing -CH ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ - or -CO-, and two R ２ , two R ３ or R ２ and R ３ is X ＋ and a single bond formed between two benzene rings connecting the two. m1 represents an integer of 1 to 5, and when m1 is 2 or more, the groups in the parentheses may be the same or different. mm1 represents an integer of 2 to 5, and a plurality of R １ may be the same or different from each other. m2 represents an integer of 0 to 4, and satisfies 1≦m1+m2≦5. When m2 is 2 or more, a plurality of R ２ may be the same or different from each other. m3 represents an integer of 0 to 5, and when m3 is 2 or more, a plurality of R ３ may be the same or different from each other. m4 represents an integer of 0 to 5, satisfying 0≦m3+m4≦5, and when m4 is 2 or more, the groups in the parentheses may be the same or different. mm4 represents 0 or 1. AI － represents an organic cation.

2. 2. The acid generator according to claim 1, wherein the cation of the salt represented by formula (I) is a cation represented by formula (IC-1). [In formula (IC-1), m10, m11, X, A １ , Ar １ , m1, R ２ , R ３ , m2 and m3 have the same meanings as in formula (I). R １Ａ and R １Ｂ are each independently a hydroxy group, *-X １ -R １０ or *-X ２ -L １１ -X １ -R １０ represents X １ , X ２ , L １１ and R １０ have the same meaning as in formula (I).

3. 2. The acid generator according to claim 1, wherein m10 is 1 or 2.

4. 2. The acid generator according to claim 1, wherein the cation of the salt represented by formula (I) is one selected from the cations represented by formulas (IC-2) to (IC-10): [Formula (IC-2) to formula (IC-10), A １ , Ar １ , m3, R ２ and R ３ represents the same meaning as in formula (I). R １Ａ , R １Ｂ and R １Ｃ are each independently a hydroxy group, *-X １ -R １０ or *-X ２ -L １１ -X １ -R １０ represents X １ , X ２ , L １１ and R １０ have the same meanings as in formula (I). X ７ is a single bond, -CH ２ -, -O-, -S-, -CO-, -SO-, -NR １１ -or-SO ２ - represents.

5. A １ But, ***-X ０１ -L ０１ - or ***-L ０１ -X ０１ - and X ０１ is -O-, -CO-, -S-, -SO-, -NR １１ -or-SO ２ represents -, L ０１ represents a single bond or a hydrocarbon group having 1 to 18 carbon atoms (the hydrocarbon group may have a substituent, and the —CH 2 - is -O-, -CO-, -S-, -SO-, -NR １１ -or-SO ２ - may be replaced by . *** is Ar １ The acid generator of claim 1 , wherein the bonding site is

6. X ０１ 6. The acid generator according to claim 5, wherein is —O—, —CO—, or —S—.

7. R １ is a hydroxy group, *—O—R １０ or *-O-L １１ -CO-O-R １０ (* indicates Ar １ The acid generator according to claim 1 , wherein

8. R １ But *-X １ -R １０ or *-X ２ -L １１ -X １ -R １０ and R １０ 2. The acid generator according to claim 1, wherein the acid labile group is a group represented by formula (1a) or a group represented by formula (2a). [In formula (1a), R aa1 , R aa2 and R aa3 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 group combining these, or R aa1 and R aa2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R aa3 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 group combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may contain a halogen atom. * indicates a binding site.] [In formula (2a), R aa1’ and R aa2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa1’ represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R aa2’ and R aa3’ are bonded to each other and bonded to -C-X ａ Together with —, it forms a heterocyclic group having 3 to 20 carbon atoms, and —CH contained in the hydrocarbon group and the heterocyclic group ２ - may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X a represents an oxygen atom or a sulfur atom. * indicates a binding site.]

9. 2. The acid generator according to claim 1, wherein X is a sulfur atom.

10. Ar １ 2. The acid generator according to claim 1, wherein is a group derived from a benzene ring, a naphthalene ring, a furan ring, or a thiophene ring.

11. AI － 2. The acid generator according to claim 1, wherein is a sulfonate anion, a sulfonylimide anion, or a sulfonylmethide anion.

12. AI － 2. The acid generator according to claim 1, wherein: is a sulfonate anion, and the sulfonate anion is an anion represented by formula (IA): [In formula (IA), L ｂ１ represents a single bond or an (nb1+1)-valent hydrocarbon group which may have a substituent, and —CH ２ - is -O-, -S-, -CO-, -SO- 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 —CH ２ - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced with -. 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-, -CO-, -SO- or -SO ２ It may be replaced with -. 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.]

13. The acid generator according to any one of claims 1 to 12, The resist composition further comprises a salt that generates an acid weaker in acidity than the acid generated from the salt represented by formula (I).

14. 14. The resist composition according to claim 13, wherein the solid content of the resist composition comprises a salt represented by formula (I) and a salt that generates an acid having a weaker acidity than the acid generated from the salt represented by formula (I).

15. The acid generator according to any one of claims 1 to 12, and a compound having a structure represented by formula (L0): [In formula (L0), Ar ｌｋ represents an aromatic hydrocarbon ring having 6 to 18 carbon atoms which may have a substituent. X ｌｋ represents a single bond or a carbonyl group. R ｌｋ represents a hydrogen atom or an acid labile group. lk represents an integer of 1 or more, and when lk is 2 or more, the groups in the parentheses may be the same or different. * indicates a binding site. Io represents an integer of 1 or more.

16. 16. The resist composition according to claim 15, wherein the compound having a structure represented by formula (L0) is a compound represented by formula (LX). [In formula (LX), Ar ｋ１ and Ar ｋ２ each independently represents an aromatic hydrocarbon ring having 6 to 18 carbon atoms. X ｌｋ１ and X ｌｋ２ each independently represents a single bond or a carbonyl group. R ｌｋ１ and R ｌｋ２ each independently represents a hydrogen atom or an acid labile group. Lx represents a hydrocarbon group having 1 to 80 carbon atoms which may have a substituent, and —CH 2 - is -O-, -CO-, -S-, -SO-, -NR １１ -or-SO ２ It may be replaced with -. R ｌｋ１１ and R ｌｋ２２ each independently represents a hydrocarbon group having 1 to 20 carbon atoms which may have a halogen atom or a substituent, and —CH 2 - is -O-, -CO-, -S-, -SO-, -NR １１ -or-SO ２ - may be replaced by R ｌｋ１１ and R ｌｋ２２ , R ｌｋ１１ and Lx or R ｌｋ２２ and Lx may be bonded to form a ring, and the ring may have a substituent. 2 - is -O-, -S-, -CO-, -SO-, -NR １１ -or-SO ２ It may be replaced with -. lx2 represents an integer of 1 to 6, and when lx2 is 2 or more, the groups in the parentheses may be the same or different. lk1' represents an integer of 1 to 13, and when lk1' is 2 or more, the groups in the parentheses may be the same or different. lk11' represents an integer of 0 to 12, and when lk11' is 2 or more, the groups in the parentheses may be the same or different. lk2' represents an integer of 1 to 13, and when lk2' is 2 or more, the groups in the parentheses may be the same or different. lk22′ represents an integer of 0 to 12, and when lk22′ is 2 or greater, the groups in the parentheses may be the same or different.]

17. 16. The resist composition according to claim 15, wherein the compound having a structure represented by formula (L0) is a resin containing 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 —CH ２ - is -O-, -CO- or -NR ａ２８ 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 a carbonyl group. nA2 represents an integer of 1 to 5, and 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, and 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.

18. (1) a step of applying the resist composition according to claim 13 onto a substrate; (2) a step of drying the applied composition to form a composition layer; (3) exposing the composition layer to light; (4) a step of heating the composition layer after exposure; and (5) A method for producing a resist pattern, comprising the step of developing the composition layer after heating.

19. A salt represented by formula (I): [In formula (I), m10 represents an integer of 1 to 3, and when m10 is 2 or greater, the groups in the parentheses may be the same or different. m11 represents an integer of 0 to 2, and satisfies 2≦m10+m11≦3; when m10+m11=2, X represents an iodine atom; when m10+m11=3, X represents a sulfur atom; and when m11 is 2 or greater, the groups in parentheses may be the same as or different from each other. A １ and A ２ each independently represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have a substituent. ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ It may be replaced by - or -CO-. R １１ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ar １ and Ar ２ each independently represents an aromatic hydrocarbon group having 6 to 10 carbon atoms or a heterocyclic hydrocarbon group having 4 to 9 carbon atoms, and the aromatic hydrocarbon group and the heterocyclic hydrocarbon group may have a substituent. R １ and R ４ are each independently a hydroxy group, *-X １ -R １０ or *-X ２ -L １１ -X １ -R １０ Represents. X １ and X ２ each independently represents —CO—O—, —O—CO—, —O—CO—O— or —O—. * indicates Ar １ or Ar ２ represents the binding site with L １１ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ It may be replaced by - or -CO-. R １０ represents an acid labile group. R ２ and R ３ each independently represents a halogen atom or a hydrocarbon group having 1 to 28 carbon atoms, and the hydrocarbon group may have a substituent. ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ - or -CO-, and two R ２ , two R ３ or R ２ and R ３ is bonded, and X ＋ may form a ring containing -CH ２ - is -O-, -S-, -SO ２ -, -SO-, -NR １１ - or -CO-, and two R ２ , two R ３ or R ２ and R ３ is X ＋ and a single bond formed between two benzene rings connecting the two. m1 represents an integer of 1 to 5, and when m1 is 2 or more, the groups in the parentheses may be the same or different. mm1 represents an integer of 2 to 5, and a plurality of R １ may be the same or different from each other. m2 represents an integer of 0 to 4, and satisfies 1≦m1+m2≦5. When m2 is 2 or more, a plurality of R ２ may be the same or different from each other. m3 represents an integer of 0 to 5, and when m3 is 2 or more, a plurality of R ３ may be the same or different from each other. m4 represents an integer of 0 to 5, satisfying 0≦m3+m4≦5, and when m4 is 2 or more, the groups in the parentheses may be the same or different. mm4 represents 0 or 1. AI － represents an organic cation.

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