Salt, acid generator, resist composition, and method for producing resist pattern

Abstract

To produce a resist pattern having good line edge roughness (LER).SOLUTION: An acid generator contains a salt represented by formula (I).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 resist composition that contains a salt represented by the following formula as an acid generator.

[0003] [ka] [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-085878 A Summary of the Invention [Problem to be solved by the invention]

[0005] There is a demand for technology that can form resist patterns with good line edge roughness (LER). [Means for solving the problem]

[0006] The present invention includes the following inventions. [Invention 1] An acid generator comprising a salt represented by formula (I):

[0007] [ka]

[0008] [In formula (I), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1. When X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0.

[0009] R 1A and R 1B are each independently -X 1 -R 10 , -X 1 -L 10 -X 2 -R 10 Represents. X 1 and X 2 are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (wherein * represents a benzene ring or L 10 ) represents the binding site with.

[0010] L 10 represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-.

[0011] R 10 represents a base labile group. R 4 represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, and -CH2- contained in the hydrocarbon group optionally being replaced by -O-, -S-, -CO-, -SO- or -SO2-.

[0012] R 7 , R 8 and R 9 each independently represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. When X is a sulfur atom, R 7 and R 8 or R 8 and R 9 Combined, S + The R forming the ring may form a ring containing 7 and R8 or R 8 and R 9 is S + and -CH2- may be a single bond formed between two benzene rings that are bonded to each other. -CH2- contained in the ring may be replaced with -O-, -S-, -CO-, -SO- or -SO2-.

[0013] m1A represents an integer of 0 to 5, and when m1A is 2 or more, a plurality of R 1A may be the same or different from each other. m1B represents an integer of 0 to 4, and when m1B is 2 or more, a plurality of R 1B may be the same or different, provided that either m1A or m1B is an integer of at least 1.

[0014] m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R 4 may be the same or different, and satisfy the relationship 0≦m1A+m4≦5. m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R 7 may be the same or different, and satisfy the relationship 0≦m1B+m7≦4.

[0015] m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R 8 may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R 9 may be the same or different from each other.

[0016] AI - represents an organic anion. [Invention 2] m1A is an integer of 1 to 3, R 1A But -O-CO-R 10 Or -OL 10 -CO-OR 10 The acid generator according to [Invention 1],

[0017] [Invention 3] R 10 The acid generator according to [Invention 1] or [Invention 2], wherein the base labile group is a group represented by formula (1b):

[0018] [ka]

[0019] [In formula (1b), R ba1 and R ba2 each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom. R ba3 represents a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom.

[0020] * denotes a binding site.] [Invention 4] AI - is an anion represented by formula (IA).

[0021] [ka]

[0022] [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- or -SO2-.

[0023] 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- or -SO2-.

[0024] Y b1represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0025] nb1 represents an integer of 1 to 6. When nb1 is 2 or more, the groups in the multiple parentheses may be the same or different.] [Invention 5] Y b1 represents a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0026] [Invention 6] AI - is an anion represented by formula (I-A1).

[0027] [ka]

[0028] [In formula (I-A1), 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.

[0029] z1 represents an integer of 0 to 6. When z1 is 2 or more, the groups in the multiple parentheses may be the same or different. X 1 represents -O-CO-, -CO-O-, -O-CO-O- or -O-.

[0030] L b2represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0031] L b3 represents a single bond or a (nb2+1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0032] Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0033] nb2 represents an integer of 1 to 3. When nb2 is 2 or more, the groups in the multiple parentheses may be the same or different.] [Invention 7] AI - is an anion represented by formula (I-A2):

[0034] [ka]

[0035] [In formula (I-A2), R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkyl group may be replaced with -O- or -CO-.

[0036] 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- or -SO2-.

[0037] Yb1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0038] nb4 represents an integer of 1 to 5. When nb4 is 2 or more, the groups in the multiple parentheses may be the same or different. nb3 represents an integer of 0 to 4. When nb3 is 2 or more, a plurality of R b1 may be the same or different from each other.

[0039] However, 1≦nb4+nb3≦5 is satisfied. [Invention 8] A resist composition comprising the acid generator according to any one of [Invention 1] to [Invention 7].

[0040] [Invention 9] Further comprising a resin including a structural unit having an acid labile group, The resist composition according to [Invention 8], wherein the structural unit having an acid labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6).

[0041] [ka]

[0042] [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or *-O-(CH2) k1 represents --CO--O--, k1 represents an integer of 1 to 7, and * represents a bonding site with --CO--.

[0043] R a01 , R a4 and R a5 each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 , R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, and the alkyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom.

[0044] R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom.

[0045] m1′ represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3.

[0046] [ka]

[0047] [In formula (a1-4), R a1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.

[0048] R a17represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group.

[0049] 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.

[0050] 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 a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -CO- to which they are bonded, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-.

[0051] na1 represents an integer of any one of 1 to 5, and when na1 is 2 or more, the groups in the multiple parentheses may be the same or different. na11 represents an integer of 0 to 4. When na11 is 2 or more, multiple R a17 may be the same or different from each other.

[0052] mc represents an integer from 0 to 2.

[0053] [ka]

[0054] [In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom.

[0055] Z a1 is a single bond or -(CH2) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 It represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-.

[0056] s1 represents an integer of 1 to 3. s1′ represents an integer of 0 to 3.

[0057] [ka]

[0058] [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.

[0059] 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.

[0060] X a61 is a single bond, -CO-O-* or -CO-NR 5 -*, where * represents the bonding site with Ar, and R5 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X a62 is a single bond, *-OL a61 -or*-CO-OL a62 -, * represents the bonding site with Ar, L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms.

[0061] Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.] [Invention 10] Further comprising a resin including a structural unit having an acid labile group, The resist composition according to [Invention 8] or [Invention 9], wherein the resin containing a structural unit having an acid labile group further contains a structural unit represented by formula (a2-A):

[0062] [ka]

[0063] [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.

[0064] 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.

[0065] 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.

[0066] 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 multiple parentheses may be the same or different.

[0067] 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 from 0 to 2. [Invention 11] The resist composition according to any one of [Invention 8] to [Invention 10], further comprising a salt that generates an acid that is weaker in acidity than the acid generated from the acid generator.

[0068] [Invention 12] (1) A step of applying a resist composition according to any one of [Invention 8] to [Invention 11] onto a substrate; (2) A step of drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the heated composition layer; A method for producing a resist pattern comprising the steps of:

[0069] [Invention 13] A salt represented by the above formula (I). [Invention 14] m1A is an integer of 1 to 3, R 1A But -O-CO-R 10 Or -OL 10 -CO-OR 10 The salt according to [Invention 13],

[0070] [Invention 15] R 10The salt according to [Invention 13] or [Invention 14], wherein the base labile group is a group represented by formula (1b):

[0071] [ka]

[0072] [In formula (1b), R ba1 and R ba2 each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom. R ba3 represents a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom.

[0073] * denotes a binding site.] [Invention 16] AI - is an anion represented by formula (IA).

[0074] [ka]

[0075] [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- or -SO2-.

[0076] 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- or -SO2-.

[0077] Y b1represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0078] nb1 represents an integer of 1 to 6. When nb1 is 2 or more, the groups in the multiple parentheses may be the same or different.] [Invention 17] Y b1 represents a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0079] [Invention 18] AI - is an anion represented by formula (I-A1):

[0080] [ka]

[0081] [In formula (I-A1), 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.

[0082] z1 represents an integer of 0 to 6. When z1 is 2 or more, the groups in the multiple parentheses may be the same or different. X 1 represents -O-CO-, -CO-O-, -O-CO-O- or -O-.

[0083] L b2represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0084] L b3 represents a single bond or a (nb2+1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0085] Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0086] nb2 represents an integer of 1 to 3. When nb2 is 2 or more, the groups in the multiple parentheses may be the same or different.] [Invention 19] AI - is an anion represented by formula (I-A2):

[0087] [ka]

[0088] [In formula (I-A2), R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkyl group may be replaced with -O- or -CO-.

[0089] 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- or -SO2-.

[0090] Yb1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0091] nb4 represents an integer of 1 to 5. When nb4 is 2 or more, the groups in the multiple parentheses may be the same or different. nb3 represents an integer of 0 to 4. When nb3 is 2 or more, a plurality of R b1 may be the same or different from each other.

[0092] However, 1≦nb4+nb3≦5 is satisfied. Effect of the Invention

[0093] According to the present invention, a resist pattern can be produced with good line edge roughness (LER). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0094] In this specification, "(meth)acrylic monomer" means "at least one of acrylic monomer and methacrylic monomer". The expressions "(meth)acrylate" and "(meth)acrylic acid" have the same meaning. In the group described in this specification, both a straight chain structure and a branched structure may be used. When -CH2- contained in a hydrocarbon group or the like is replaced with -O-, -S-, -CO- or -SO2-, the same example applies to each group, and the number of carbon atoms before the replacement is the number of carbon atoms of the hydrocarbon group or the like. "Combined group" means a group in which two or more of the exemplified groups are bonded, and the valence of these groups may be appropriately changed depending on the bond form. "Derived from" or "derived from" refers to a polymerizable C=C bond contained in the molecule becoming a -CC- group (single bond) by polymerization. When stereoisomers exist, all stereoisomers are included. Depending on the number of substituents and the like, hydrogen atoms in each group may be replaced with bond sites at any position and number. The number of carbon atoms in a substituent is not included in the number of carbon atoms of the substituted group. An acid labile group means a group that, when contacted with an acid (e.g., trifluoromethanesulfonic acid, etc.), the leaving group is eliminated to form a hydrophilic group (e.g., a hydroxyl group or a carboxyl group, etc.). A base labile group means a group that, when contacted with a base (e.g., trimethylamine, etc.), the leaving group is eliminated to form a hydrophilic group (e.g., a carboxyl group or a hydroxyl group, etc.).

[0095] In this specification, the term "solids content of a resist composition" refers to the sum of the components excluding the solvent (E), which will be described later, from the total amount of the resist composition. [Salt represented by formula (I)] The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as "salt (I)").

[0096] In a salt (I), the side having a positive charge is sometimes called a "cation (I)" and the side having a negative charge is sometimes called an "anion (I)".

[0097] [ka]

[0098] [In the formula, all symbols have the same meaning as defined above.] [Cation (I)] The cation (I) of the salt represented by formula (I) is a cation represented by formula (IC).

[0099] [ka]

[0100] [In formula (IC), all symbols have the same meaning as in formula (I)] R 1A and R 1B X in 1 is preferably *-CO-O-, *-O- or *-O-CO-O- (* represents a bonding site to the benzene ring), and more preferably *-O- or *-O-CO-O-.

[0101] R 1A and R 1B X in 2 is *-CO-O-, *-O-CO- or *-O-CO-O- (* is L 10 It is preferable that the bond is *-CO-O- or *-O-CO-.

[0102] R 1A and R 1B L included in 10 Examples of the hydrocarbon group in include chain hydrocarbon groups such as an alkanediyl group, monocyclic or polycyclic (including spiro ring) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may be a group consisting of a combination of two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and an alkanediyl group).

[0103] Examples of the alkanediyl group include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, and a heptadecane-1,17-diyl group; Examples of branched alkanediyl groups include ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. The terminal of the branched alkanediyl group may be an alkyl group such as a methyl group.

[0104] The chain hydrocarbon group preferably has 1 to 18 carbon atoms, more preferably 1 to 12 carbon atoms, even more preferably 1 to 9 carbon atoms, still more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms.

[0105] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following groups: The binding site may be any position.

[0106] [ka]

[0107] Specifically, examples of the alicyclic hydrocarbon group include monocyclic divalent alicyclic hydrocarbon groups, such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, and a cyclooctane-1,5-diyl group, and the like. Examples of the divalent alicyclic hydrocarbon group include a cycloalkyl group such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, spirocyclohexane-1,2'-cyclopentane group, and spiroadamantane-2,3'-cyclopentane group, and a polycyclic cycloalkanediyl group such as a spiro ring having a cycloalkyl group bonded to a norbornyl group or an adamantyl group by a spiro bond. The 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.

[0108] 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 number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and further preferably 6 to 10.

[0109] Examples of the group combining two or more types include a group combining an alicyclic hydrocarbon group with an alkanediyl group, a group combining an aromatic hydrocarbon group with an alkanediyl group, and a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group. In the combination, two or more types of each of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may be combined. In addition, when any group is X 1 Or X 2 may be bound to

[0110] 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-.

[0111] Examples of groups combining an aromatic hydrocarbon group and an alkanediyl group include -divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-, and the like.

[0112] Examples of groups combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group include -aromatic hydrocarbon group-alicyclic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-.

[0113] L 10 The --CH2-- contained in the hydrocarbon group having 1 to 28 carbon atoms may be replaced by --O--, --S--, --SO2-- or --CO--. L 10 When --CH2-- contained in the hydrocarbon group having 1 to 28 carbon atoms is replaced with --O--, --S--, --SO2-- or --CO--, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the hydrocarbon group.

[0114] Examples of groups in which -CH2- in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), an oxy group (a group in which -CH2- in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), a thio ... A group in which -CH2- in the alkyl group is replaced with -S-), a sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), an alkylthio group (a group in which -CH2- at any position in an alkyl group is replaced with -S-), an alkylsulfonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -SO2-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -O-C O-), alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -CO-), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in an alkyl group is replaced with -CO-O-), alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced with -O-), alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position in an alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl group (a an alkanediyl group in which -CH2- at any position is replaced with -CO-), an alkanediylcarbonyloxy group (an alkanediyl group in which -CH2-CH2- at any position is replaced with -CO-O-), an alkanediylsulfonyl group (an alkanediyl group in which -CH2- at any position is replaced with -SO2-), an alkanediylthio group (an alkanediyl group in which -CH2- at any position is replaced with -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group,Examples of the aromatic hydrocarbon group include an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a combination of two or more of these groups.

[0115] Examples of the alkoxy group include alkoxy groups having 1 to 27 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, etc. The number of carbon atoms in the alkoxy group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0116] The alkylthio group includes an alkylthio group having 1 to 27 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, an octylthio group, a 2-ethylhexylthio group, a nonylthio group, a decylthio group, an undecylthio group, etc. The number of carbon atoms in the alkylthio group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0117] Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 27 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, and butoxycarbonyl groups. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 28 carbon atoms, such as acetyl, propionyl, and butyryl groups. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 27 carbon atoms, such as acetyloxy, propionyloxy, and butyryloxy groups. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The alkylcarbonyloxy group preferably has 2 to 11 carbon atoms, more preferably 2 to 6 carbon atoms, further preferably 2 to 4 carbon atoms, and even more preferably 2 or 3 carbon atoms.

[0118] Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 27 carbon atoms, such as a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, a butylsulfonyl group, a pentylsulfonyl group, a hexylsulfonyl group, an octylsulfonyl group, a 2-ethylhexylsulfonyl group, a nonylsulfonyl group, a decylsulfonyl group, an undecylsulfonyl group, etc. The number of carbon atoms in the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0119] The alkanediyloxy group includes an alkanediyloxy group having 1 to 27 carbon atoms, such as a methyleneoxy group, an ethyleneoxy group, a propanediyloxy group, a butanediyloxy group, a pentanediyloxy group, etc. The number of carbon atoms in the alkanediyloxy group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0120] Examples of the alkanediyloxycarbonyl group include alkanediyloxycarbonyl groups having 2 to 27 carbon atoms, such as methyleneoxycarbonyl group, ethyleneoxycarbonyl group, propanediyloxycarbonyl group, butanediyloxycarbonyl group, etc. Examples of the alkanediylcarbonyl group include alkanediylcarbonyl groups having 2 to 28 carbon atoms, such as methylenecarbonyl group, ethylenecarbonyl group, propanediylcarbonyl group, butanediylcarbonyl group, pentanediylcarbonyl group, etc. Examples of the alkanediylcarbonyloxy group include alkanediylcarbonyloxy groups having 2 to 27 carbon atoms, such as methylenecarbonyloxy group, ethylenecarbonyloxy group, propanediylcarbonyloxy group, butanediylcarbonyloxy group, etc. The number of carbon atoms in the alkanediyloxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3.

[0121] The alkanediylsulfonyl group includes an alkanediylsulfonyl group having 1 to 27 carbon atoms, such as a methylenesulfonyl group, an ethylenesulfonyl group, a propylenesulfonyl group, etc. The number of carbon atoms in the alkanediylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0122] The alkanediylthio group includes an alkanediylthio group having 1 to 27 carbon atoms, such as a methylenethio group, an ethylenethio group, a propylenethio group, etc. The number of carbon atoms in the alkanediylthio group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0123] Examples of the cycloalkoxy group include a cycloalkoxy group having 3 to 27 carbon atoms, such as a cyclohexyloxy group. Examples of the cycloalkylalkoxy group include a cycloalkylalkoxy group having 4 to 27 carbon atoms, such as a cyclohexylmethoxy group. Examples of the alkoxycarbonyloxy group include an alkoxycarbonyloxy group having 2 to 26 carbon atoms, such as a butoxycarbonyloxy group. Examples of the aromatic hydrocarbon group-carbonyloxy group include an aromatic hydrocarbon group-carbonyloxy group having 7 to 27 carbon atoms, such as a benzoyloxy group. Examples of the aromatic hydrocarbon group-carbonyl group include an aromatic hydrocarbon group-carbonyl group having 7 to 28 carbon atoms, such as a benzoyl group. Examples of the aromatic hydrocarbon group-oxy group include an aromatic hydrocarbon group-oxy group having 6 to 27 carbon atoms, such as a phenyloxy group.

[0124] Examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. -O- or -CO- in the groups shown below may be replaced by -S- or -SO2-, respectively. The bonding site may be at any position.

[0125] [ka]

[0126] L 10 The substituents which may be contained in L include a halogen atom and a cyano group. 10In the case of a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group such as an alkyl group, the chain hydrocarbon group such as an alkyl group can be a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. 10 The -CH2- in the chain hydrocarbon group such as the alkyl group in the formula (I) is replaced with -O-, -CO-, -S- or -SO2-, thereby forming L 10 can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, or a sulfonyl group.

[0127] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L 10 The substituent in is preferably an alkyl group having 1 to 4 carbon atoms, a hydroxyl group or a halogen atom, more preferably an alkyl group having 1 to 4 carbon atoms or a halogen atom, and further preferably a methyl group or a fluorine atom.

[0128] L 10 is preferably an alkanediyl group having 1 to 10 carbon atoms (-CH2- contained in the alkanediyl group may be replaced with -O- or -CO-) or a group combining an alkanediyl group having 1 to 4 carbon atoms with an alicyclic hydrocarbon group having 3 to 12 carbon atoms (-CH2- contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced with -O- or -CO-), more preferably an alkanediyl group having 1 to 6 carbon atoms, even more preferably an alkanediyl group having 1 to 3 carbon atoms, and even more preferably a methylene group.

[0129] R 1A and R 1B R included in 10 The base labile group of R is a group that, when contacted with a base (e.g., 2.38% aqueous tetramethylammonium hydroxide solution), 10 When a leaving group including a group represented by the following formula is eliminated, it forms a carboxy group or a hydroxy group.

[0130] The base labile group is preferably a group represented by formula (1b) (hereinafter sometimes referred to as "base labile group (1b)").

[0131] [ka]

[0132] [In formula (1b), R ba1 and R ba2 each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom. R ba3 represents a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom.

[0133] * denotes a binding site.] R ba1 , R ba2 and R ba3 Examples of the alkyl group having a fluorine atom include a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a perfluoroethyl group, a 2,2,3,3,3-pentafluoropropyl group, a 1-trifluoromethyl-2,2,2-trifluoroethyl group, a perfluoropropyl group, a 2,2,3,3,4,4,4-heptafluorobutyl group, a perfluorobutyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluoropentyl group, a perfluorohexyl group, etc. The number of carbon atoms of the alkyl group having a fluorine atom is preferably 1 to 5, more preferably 1 to 4, and further preferably 1 to 3.

[0134] R ba1 is preferably a hydrogen atom or a fluorine atom. R ba2 is preferably a hydrogen atom, a fluorine atom or a trifluoromethyl group, and more preferably a hydrogen atom or a fluorine atom.

[0135] R ba3is preferably a fluorine atom, a perfluoroalkyl group having 1 to 4 carbon atoms, or a perfluoroalkylmethyl group having 2 to 5 carbon atoms, and more preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms.

[0136] -C(R ba1 )(R ba2 )(R ba3 ) is preferably a perfluoroalkyl group having 1 to 4 carbon atoms, a perfluoroalkylmethyl group having 1 to 4 carbon atoms, or a 1-trifluoromethyl-2,2,2-trifluoroethyl group, and more preferably a perfluoroalkyl group having 1 to 4 carbon atoms or a perfluoroalkylmethyl group having 1 to 4 carbon atoms.

[0137] R 1A The bonding position of to the benzene ring is X + The position of X may be ortho, meta, or para relative to the position of the benzene ring. + At least one of the groups is preferably bonded at the ortho or para position relative to the bonding position of the benzene ring bonded to the group.

[0138] R 1B The bonding position of to the benzene ring is X + The bonding position of X may be ortho, meta, or para. + It is preferable that at least one of them is bonded at the ortho-position or meta-position with respect to the bonding positions of the above.

[0139] R 1A and R 1B are each independently, -OR 10 , -CO-OR 10 , -O-CO-R 10 , -O-CO-OR 10 Or -OL 10 -CO-OR 10 is preferably -O-CO-R 10 , -O-CO-OR 10 Or -OL 10 -CO-OR 10More preferably, it is -O-CO-R 10 Or -OL 10 -CO-OR 10 It is even more preferable that:

[0140] m1A is preferably an integer of 0 to 4, more preferably an integer of 0 to 3, even more preferably an integer of 1 to 3, even more preferably 1 or 2, and even more preferably 1.

[0141] m1B is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, even more preferably 0 or 1, and even more preferably 0.

[0142] R 4 , R 7 , R 8 and R 9 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 4 , R 7 , R 8 and R 9 Examples of the hydrocarbon group having 1 to 36 carbon atoms include chain hydrocarbon groups such as alkyl groups and alkanediyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these. The number of carbon atoms in the hydrocarbon group is preferably 1 to 30, more preferably 1 to 24, and even more preferably 1 to 18.

[0143] R 4 , R 7 , R 8 and R 9 The alkyl group in the formula (I) 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.

[0144] R 4 , R 7 , R 8 and R 9 The alkanediyl group in the formula (I) is a linear or branched alkanediyl group, and examples thereof include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, and a hexane-1,6-diyl group; and branched alkanediyl groups such as 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.

[0145] R 4 , R 7 , R 8 and R 9 The chain hydrocarbon group preferably has 1 to 18 carbon atoms, more preferably 1 to 12 carbon atoms, even more preferably 1 to 9 carbon atoms, still more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and still more preferably 1 to 3 carbon atoms.

[0146] R 4 , R 7 , R 8 and R 9 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic, and examples thereof include the groups shown below. The bonding site may be any position.

[0147] [ka]

[0148] Specifically, the monocyclic alicyclic hydrocarbon group includes monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl. The polycyclic alicyclic hydrocarbon group includes polycyclic cycloalkyl groups such as decahydronaphthyl, adamantyl, and norbornyl, cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane and spiroadamantane-2,3'-cyclopentane, and spiro rings having cycloalkyl groups bonded to norbornyl or adamantyl groups via spiro. The carbon number of the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12.

[0149] R 4 , R 7 , R 8 and R 9 Examples of the aromatic hydrocarbon group in 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 further preferably 6 to 10 carbon atoms.

[0150] Examples of groups formed by combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group include a group formed by combining an aromatic hydrocarbon group with a chain hydrocarbon group (for example, an aromatic hydrocarbon group-alkanediyl group-*, an alkyl group-aromatic hydrocarbon group-*, an alkyl group-aromatic hydrocarbon group-alkanediyl group-*, where -CH2- contained in the alkanediyl group and the alkyl group may be replaced by -O-, -CO-, -S-, or -SO2-), a group formed by combining an alicyclic hydrocarbon group with a chain hydrocarbon group (for example, an alicyclic hydrocarbon group-alkanediyl group-*, Examples of such groups include an alkyl group-alicyclic hydrocarbon group-*, an alkyl group-alicyclic hydrocarbon group-alkanediyl group-*, an alkyl group-alicyclic hydrocarbon group-alkanediyl group-*, -CH2- contained in the alicyclic hydrocarbon group, the alkanediyl group and the alkyl group may be replaced with -O-, -CO-, -S- or -SO2-, and a group combining an aromatic hydrocarbon group and an alicyclic hydrocarbon group (for example, an aromatic hydrocarbon group-alicyclic hydrocarbon group-*, an alicyclic hydrocarbon group-aromatic hydrocarbon group-*, -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-). * represents a bonding site.

[0151] 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.

[0152] 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.

[0153] 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.

[0154] 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.

[0155] In addition, in the combination, two or more types of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined, and any of the groups may be bonded to a benzene ring.

[0156] R 4 , R 7 , R 8 and R 9 When -CH2- in the hydrocarbon group represented by the formula (I) is replaced by -O-, -CO-, -S-, -SO-, or -SO2-, the number of carbon atoms before the replacement is regarded as the total number of carbon atoms in the hydrocarbon group. In addition, the number may be 1 or 2 or more.

[0157] Examples of groups in which -CH2- in a hydrocarbon group is replaced by -O-, -CO-, -S-, -SO- or -SO2- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), and a carboxyl group (a group in which -CH2- at any position in an alkyl group is replaced by -O-). H2- is replaced by -O-CO-), alkylcarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced by -CO-), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in the alkyl group is replaced by -CO-O-), alkylthio group (a group in which -CH2- at any position in the alkyl group is replaced by -S-), alkylsulfyl group (a group in which -CH2- at any position in the alkyl group is replaced by -SO-), alkylsulfon ... in which -CH2- is replaced by -SO2-), oxy group (a group in which -CH2- in a methylene group is replaced by -O-), carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), thio group (a group in which -CH2- in a methylene group is replaced by -S-), sulfyl group (a group in which -CH2- in a methylene group is replaced by -SO-), sulfonyl group (a group in which -CH2- in a methylene group is replaced by -SO2-), alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced by -SO-), is replaced by -O-), an alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -CO-O-), an alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -S-),Examples of such groups include an alkanediylsulfyl group (a group in which -CH- at any position in an alkanediyl group is replaced with -SO-), an alkanediylsulfonyl group (a group in which -CH- at any position in an alkanediyl group is replaced with -SO-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group in which two or more of these groups are combined.

[0158] Examples of the alkoxy group include alkoxy groups having 1 to 35 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, etc. The number of carbon atoms in the alkoxy group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0159] The alkoxycarbonyl group, alkylcarbonyl group and alkylcarbonyloxy group represent groups in which a carbonyl group or a carbonyloxy group is bonded to the above-mentioned alkyl group or alkoxy group.

[0160] Examples of the alkoxycarbonyl group include an alkoxycarbonyl group having 2 to 35 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include an alkylcarbonyl group having 2 to 36 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include an alkylcarbonyloxy group having 2 to 35 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The alkylcarbonyloxy group preferably has 2 to 11 carbon atoms, more preferably 2 to 6 carbon atoms, further preferably 2 to 4 carbon atoms, and even more preferably 2 or 3 carbon atoms.

[0161] The alkylthio group includes an alkylthio group having 1 to 35 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, an octylthio group, a 2-ethylhexylthio group, a nonylthio group, a decylthio group, an undecylthio group, etc. The number of carbon atoms in the alkylthio group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0162] The alkylsulfyl group includes alkylsulfyl groups having 1 to 35 carbon atoms, such as methylsulfyl group, ethylsulfyl group, propylsulfyl group, butylsulfyl group, pentylsulfyl group, hexylsulfyl group, octylsulfyl group, 2-ethylhexylsulfyl group, nonylsulfyl group, decylsulfyl group, undecylsulfyl group, etc. The number of carbon atoms in the alkylsulfyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0163] Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 35 carbon atoms, such as a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, a butylsulfonyl group, a pentylsulfonyl group, a hexylsulfonyl group, an octylsulfonyl group, a 2-ethylhexylsulfonyl group, a nonylsulfonyl group, a decylsulfonyl group, an undecylsulfonyl group, etc. The number of carbon atoms in the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0164] The alkanediyloxy group includes an alkanediyloxy group having 1 to 35 carbon atoms, such as a methyleneoxy group, an ethyleneoxy group, a propanediyloxy group, a butanediyloxy group, a pentanediyloxy group, etc. The number of carbon atoms in the alkanediyloxy group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0165] Examples of the alkanediyloxycarbonyl group include alkanediyloxycarbonyl groups having 2 to 35 carbon atoms, such as methyleneoxycarbonyl group, ethyleneoxycarbonyl group, propanediyloxycarbonyl group, butanediyloxycarbonyl group, etc. Examples of the alkanediylcarbonyl group include alkanediylcarbonyl groups having 2 to 36 carbon atoms, such as methylenecarbonyl group, ethylenecarbonyl group, propanediylcarbonyl group, butanediylcarbonyl group, pentanediylcarbonyl group, etc. Examples of the alkanediylcarbonyloxy group include alkanediylcarbonyloxy groups having 2 to 35 carbon atoms, such as methylenecarbonyloxy group, ethylenecarbonyloxy group, propanediylcarbonyloxy group, butanediylcarbonyloxy group, etc. The number of carbon atoms in the alkanediyloxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3.

[0166] The alkanediylthio group includes an alkanediylthio group having 1 to 35 carbon atoms, such as a methylenethio group, an ethylenethio group, a propylenethio group, etc. The number of carbon atoms in the alkanediylthio group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0167] The alkanediylsulfyl group includes an alkanediylsulfyl group having 1 to 35 carbon atoms, such as a methylenesulfyl group, an ethylenesulfyl group, a propylenesulfyl group, etc. The number of carbon atoms in the alkanediylsulfyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0168] The alkanediylsulfonyl group includes an alkanediylsulfonyl group having 1 to 35 carbon atoms, such as a methylenesulfonyl group, an ethylenesulfonyl group, a propylenesulfonyl group, etc. The number of carbon atoms in the alkanediylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0169] Examples of the cycloalkoxy group include a cycloalkoxy group having 3 to 35 carbon atoms, such as a cyclohexyloxy group. Examples of the cycloalkylalkoxy group include a cycloalkylalkoxy group having 4 to 35 carbon atoms, such as a cyclohexylmethoxy group. Examples of the alkoxycarbonyloxy group include an alkoxycarbonyloxy group having 2 to 34 carbon atoms, such as a butoxycarbonyloxy group. Examples of the aromatic hydrocarbon group-carbonyloxy group include an aromatic hydrocarbon group-carbonyloxy group having 7 to 36 carbon atoms, such as a benzoyloxy group. Examples of the aromatic hydrocarbon group-carbonyl group include an aromatic hydrocarbon group-carbonyl group having 7 to 36 carbon atoms, such as a benzoyl group. Examples of the aromatic hydrocarbon group-oxy group include an aromatic hydrocarbon group-oxy group having 6 to 35 carbon atoms, such as a phenyloxy group.

[0170] Examples of the group in which -CH2- in the alicyclic hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include the groups shown below. Also included are the groups in which -O- in the groups shown below is replaced by -S-, and -CO- is replaced by -SO- or -SO2-. The bonding site may be any position.

[0171] [ka]

[0172] R 4 , R 7 , R 8 and R 9 Examples of the substituent that the hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, and the like. Examples of the halogen atom include the same groups as those mentioned above.

[0173] R 4 , R 7 , R 8 and R 9 When R is a hydrocarbon group having a halogen atom, 4 , R 7 , R 8 and R 9 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.

[0174] Examples of the alkyl group having a halogen atom include haloalkyl groups having 1 to 12 carbon atoms, such as fluorinated alkyl groups having 1 to 12 carbon atoms, chlorinated alkyl groups having 1 to 12 carbon atoms, brominated alkyl groups having 1 to 12 carbon atoms, and iodinated alkyl groups having 1 to 12 carbon atoms. Examples of the haloalkyl groups include perfluoroalkyl groups having 1 to 12 carbon atoms (trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, etc.), 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, and iodomethyl group. The number of carbon atoms in the haloalkyl group is preferably 1 to 9, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3.

[0175] The -CH2- contained in the haloalkyl group may be replaced by -O- or -CO-, etc., and examples thereof include a haloalkoxy group, a haloalkoxycarbonyl group, a haloalkylcarbonyl group, a haloalkylcarbonyloxy group, etc. Specific examples thereof include a haloalkoxy group having 1 to 11 carbon atoms, a haloalkoxycarbonyl group having 2 to 11 carbon atoms, a haloalkylcarbonyl group having 2 to 12 carbon atoms, a haloalkylcarbonyloxy group having 2 to 11 carbon atoms, etc., and examples thereof include groups in which one or more hydrogen atoms of the above-exemplified groups are replaced by halogen atoms.

[0176] The hydrocarbon group may have one substituent or multiple substituents. m4 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, and even more preferably 0, 1 or 2.

[0177] R 4 The bonding position of to the benzene ring is X + may be ortho, meta, or para relative to the bonding position of the benzene ring to which m4 is bonded. When m4 is 1 or 2, at least one R 4 X +is preferably bonded to the para or meta position relative to the bonding position of the benzene ring to which m4 is bonded. 4 X + is preferably bonded at the ortho- or meta-position with respect to the bonding position of the benzene ring to which it is bonded.

[0178] R 4 The bond position of the benzene ring to which X is bonded is + In the benzene ring to which X is attached, + The bonding position of R may be ortho, meta, or para. 4 The benzene ring to which X is attached is + It is preferably bonded at the para or meta position relative to the bonding position of (a), and more preferably bonded at the para position.

[0179] m7 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. R 7 The bonding position of to the benzene ring is X + The ortho, meta or para position may be any of the positions with respect to the bonding position of R. 7 But X + It is preferably bonded at the ortho- or meta-position relative to the bonding position of the above, and more preferably bonded at the meta-position.

[0180] m8 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.

[0181] m9 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.

[0182] When at least one of m8 and m9 is an integer of 1 or more, R 8 and / or R9 The bonding position of to the benzene ring is X + The ortho, meta or para position may be any of the positions with respect to the bonding position of R. 8 and / or R 9 But X + It is preferably bonded at the meta or para position relative to the bonding position of (a), and more preferably bonded at the para position.

[0183] R 4 is preferably a halogen atom or an alkyl group having 1 to 12 carbon atoms which may have a halogen atom (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), more preferably a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a fluorine atom (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), still more preferably a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the fluorinated alkyl group or the alkyl group may be replaced with -O- or -CO-), still more preferably a fluorine atom, a bromine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), and still more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a hydroxy group, a methoxy group, a methyl group or a t-butyl group.

[0184] R 7 , R 8 and R 9are each independently preferably a halogen atom or an alkyl group having 1 to 12 carbon atoms which may have a halogen atom (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), more preferably a halogen atom, a fluorinated alkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the fluorinated alkyl group or the alkyl group may be replaced with -O- or -CO-), and A group (wherein the -CH2- contained in the fluorinated alkyl group or the alkyl group may be replaced by -O- or -CO-) is more preferable, a fluorine atom, a bromine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (wherein the -CH2- contained in the alkyl group may be replaced by -O- or -CO-) is even more preferable, and a fluorine atom, an iodine atom, a trifluoromethyl group, a hydroxy group, a methoxy group, a methyl group, or a t-butyl group is even more preferable.

[0185] In another embodiment, R 8 or R 9 may contain a base labile group, each independently -X 1 -R 10 or -X 1 -L 10 -X 2 -R 10 R 8 or R 9 If R contains a base labile group, 1A or R 1B It is preferable that the base labile group is the same as that contained in

[0186] Specific examples of the cation represented by formula (IC) include cations represented by formula (IC-1) or formula (IC-2) (hereinafter, these may be referred to as "cation (IC-1)" and "cation (IC-2)", respectively).

[0187] [ka]

[0188] [In the formula, all symbols have the same meaning as defined above.] When X is a sulfur atom and m10=1, R 7 and R 8 or R 8 and R 9 Combined, S + In particular, R 8 and R 9 Combined, S + It is preferable that the cation is a cation represented by the formula (IC′).

[0189] [ka]

[0190] [where, X 7 The symbols other than the above have the same meanings as above. X 7 represents a single bond, -CH2-, -O-, -CO-, -SO-, -SO2- or -S-. X 7 is preferably a single bond, -CH2- or -O-.

[0191] Examples of the cation of the salt (I) include the cations represented by the following formulae (Ic-1) to (Ic-50).

[0192] [ka]

[0193] [ka]

[0194] [ka]

[0195] [ka]

[0196] [ka]

[0197] [ka]

[0198] [Anion (I)] AI - Examples of the organic anion represented by the formula (I) include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion.

[0199] The sulfonate anion may be an anion represented by the formula (IA).

[0200] [ka]

[0201] [In the formula, all symbols have the same meaning as defined above.] L b1 The (nb1+1)-valent hydrocarbon group is a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, or a monovalent group that is a combination of two or more of these groups, from which nb1 hydrogen atoms have been removed to form one or more L b2 Examples of such groups include groups that bond to the

[0202] The hydrocarbon group preferably has 1-48 carbon atoms, more preferably 1-42 carbon atoms, even more preferably 1-36 carbon atoms, even more preferably 1-30 carbon atoms, and even more preferably 1-24 carbon atoms.

[0203] L b1Examples of the chain hydrocarbon group include a group in which nb1 hydrogen atoms have been removed from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentanedecyl group, and a heptadecyl group. Examples of the alkenyl group include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, and a nonenyl group.

[0204] 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.

[0205] L b1 Examples of the alicyclic hydrocarbon group include a group in which nb1 hydrogen atoms have been removed from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group.

[0206] L b1Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a bridged structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are bonded by a spiro bond. Examples of the cycloalkyl group having a bridged structure include a norbornyl group and an adamantyl group. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group and a steroid group (steroid skeleton). Examples of the cycloalkyl group in which two rings are bonded by a spiro bond include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group is bonded by a spiro bond to a cycloalkyl group having 5 to 8 carbon atoms. A double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group.

[0207] More specifically, alicyclic hydrocarbon groups represented by the following formulas are included.

[0208] [ka]

[0209] L 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 even more preferably 3 to 8. b1 When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the alicyclic hydrocarbon group preferably has 6 to 24 carbon atoms, more preferably 6 to 20 carbon atoms, even more preferably 6 to 18 carbon atoms, even more preferably 6 to 12 carbon atoms, and even more preferably 7 to 12 carbon atoms.

[0210] L b1Examples 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.

[0211] More specifically, aromatic hydrocarbon groups represented by the following formulas are included.

[0212] [ka]

[0213] L b1 The aromatic hydrocarbon group has preferably 4 to 24 carbon atoms, more preferably 4 to 20 carbon atoms, even more preferably 4 to 18 carbon atoms, even more preferably 5 to 14 carbon atoms, even more preferably 5 to 10 carbon atoms, and even more preferably 6 to 10 carbon atoms.

[0214] L b1 When --CH2-- in the hydrocarbon group is replaced with --O--, --CO--, --S-- or --SO2--, the number of carbon atoms before the replacement is regarded as the number of carbon atoms in the hydrocarbon group. L b1Among the hydrocarbon groups in which -CH2- in a chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2-, there may be mentioned a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), an oxy group (a group in which -CH2- in a methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (an alkyl group in which -CH2- Examples of the substituted groups include -CH- at any position in the alkyl group, which is replaced with -CO-), alkylcarbonyloxy groups (wherein -CH-CH- at any position in the alkyl group is replaced with -CO-O-), alkanediyloxy groups (wherein -CH- at any position in the alkanediyl group is replaced with -O-), alkanediyloxycarbonyl groups (wherein -CH-CH- at any position in the alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl groups (wherein -CH- at any position in the alkanediyl group is replaced with -CO-), and alkanediylcarbonyloxy groups (wherein -CH-CH- at any position in the alkanediyl group is replaced with -CO-). Examples of the substituted groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0215] L b1 Among the above hydrocarbon groups, examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2- include groups containing structures such as cyclic ether, cyclic ketone, cyclic ester (lactone), cyclic thioether, cyclic acetal, and cyclic sulfonate ester (sultone). Specific examples include alicyclic hydrocarbon groups represented by the following formulas. The bonding position of the alicyclic hydrocarbon groups listed in the following formulas can be any position.

[0216] [ka]

[0217] L b1 Among these hydrocarbon groups, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and examples of the group in which -CH2- is replaced by -O- or -S- include groups derived from a furan ring or a thiophene ring, respectively. Specific examples include aromatic hydrocarbon groups represented by the following formulas:

[0218] [ka]

[0219] Examples of the group that combines two or more of the chain hydrocarbon group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group include a group that combines the above chain hydrocarbon group with the above alicyclic hydrocarbon group, a group that combines the above chain hydrocarbon group with the above aromatic hydrocarbon group, a group that combines the above alicyclic hydrocarbon group with the above aromatic hydrocarbon group, and a group that combines the above chain hydrocarbon group with the above alicyclic hydrocarbon group with the above aromatic hydrocarbon group. The group that combines the alicyclic hydrocarbon group with the aromatic hydrocarbon group may be a condensed ring.

[0220] L b2 The divalent hydrocarbon group includes a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group combining two or more of these groups. b1 Examples of such groups include groups that bond to the

[0221] L b2 The divalent chain hydrocarbon group, the divalent alicyclic hydrocarbon group, the divalent aromatic hydrocarbon group, and the divalent group consisting of two or more of these groups are each, within the range permitted by the upper limit of the number of carbon atoms, L b1Examples of the monovalent hydrocarbon group include a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, and a monovalent group obtained by combining two or more of these groups from which one hydrogen atom has been removed.

[0222] L b1 and L b2 The hydrogen atoms contained in the hydrocarbon group may be replaced by a substituent. b1 and L b2 Examples of the substituent that may be substituted include a halogen atom, a cyano group, and a nitro group.

[0223] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L b1 and L b2 In the case where L is a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. b1 and L b2 The -CH2- of the chain hydrocarbon group contained in the hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2-, thereby forming L b1 and L b2 The hydrocarbon group may substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, or a sulfonyl group.

[0224] 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.

[0225] Y b1 The alicyclic hydrocarbon group and the aromatic hydrocarbon group are represented by L b1Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups are the same as those exemplified in 1. When the alicyclic hydrocarbon groups and aromatic hydrocarbon groups do not have a substituent, they may be monovalent alicyclic hydrocarbon groups and aromatic hydrocarbon groups.

[0226] Y b1 Examples of the substituent that the methyl group may have include a halogen atom, a hydroxy group, a cyano group, and a nitro group. Y b1 Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, 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 by -O-, -S-, -CO- or -SO2-).

[0227] The halogen atoms are L b1 and L b2 Examples of the halogen atoms include the same halogen atoms as those exemplified as the substituents of the above. Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that may be substituted on the cyclic hydrocarbon group include chain hydrocarbon groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups combining these groups. Examples of the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups combining two or more of these groups include, within the range permitted by the upper limit of the carbon number, b1 Examples of the alkyl group include the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and the group obtained by combining two or more of these groups. b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms in which -CH2- is replaced with -O-, -S-, -CO- or -SO2- that may be substituted on the cyclic hydrocarbon group include, within the upper limit of the carbon number, 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- or -SO2-. b1The hydrocarbon group having 1 to 18 carbon atoms which the cyclic hydrocarbon group may have as a substituent may constitute a protecting group or leaving group (acid labile group or base labile group) generally used in the art.

[0228] Examples of the anion represented by formula (IA) include an anion represented by formula (I-A1) (hereinafter, sometimes referred to as "anion (I-A1)") and an anion represented by formula (I-A2) (hereinafter, sometimes referred to as "anion (I-A2)").

[0229] [ka]

[0230] [In formula (I-A1), all symbols have the same meaning as defined above.] 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.

[0231] 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.

[0232] Q b1 and Q b2 Q b1 and Q b2At 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.

[0233] 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.

[0234] 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-.

[0235] L b3 As the hydrocarbon group in the formula (IA), L b1 Examples of the hydrocarbon groups include the same groups as those exemplified in the above. L b3is preferably a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent (-CH2- contained in the aromatic hydrocarbon group may be replaced with -O- or -S-), or a group consisting of a combination of two or more of these groups, and more preferably a single bond, a chain hydrocarbon group having 1 to 6 carbon atoms, or a group represented by the following formula (Lb3-1). When -CH2- in the chain hydrocarbon group is replaced by -O- or -CO-, the number is preferably 1 to 4, and it is preferable that one -CH2-CH2- in the chain hydrocarbon group is replaced by -O-CO- or -CO-O-, or one -CH2-CH2-CH2- in the chain hydrocarbon group is replaced by -O-CO-O-.

[0236] [ka]

[0237] [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, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent.

[0238] W b3 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent.

[0239] * and ** represent binding sites, * represents X 1 represents the binding site for In formula (Lb3-1), L b31 The 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.

[0240] 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 permits, b1 Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups are the same as those exemplified by 1.

[0241] In formula (Lb3-1), L b31 The substituents which the chain hydrocarbon group may have and W b3 The substituents which the alicyclic hydrocarbon group and aromatic hydrocarbon group may have are as follows: b1 The substituents which the hydrocarbon group may have include the same groups as those exemplified above.

[0242] 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-).

[0243] Among them, W b3 As the alicyclic hydrocarbon group and aromatic hydrocarbon group, the following alicyclic hydrocarbon groups and aromatic hydrocarbon groups are preferred. 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 At least one ** represents a binding site for L b2represents 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- or -SO2-. When -CH2- contained in the alicyclic hydrocarbon group is replaced with -O-, -S-, -CO- or -SO2-, the alicyclic hydrocarbon group preferably forms an ether ring, an ester ring (lactone), a carbonate ring, a sulfonate ring (sultone) or an acetal ring.

[0244] [ka]

[0245] In formula (I-A1), L b2 is preferably a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and is preferably a single bond, -O-, -O-CO-, -CO-O-, -O-CO-O- or *-L b21 -X 2 -L b22 -**(L b21 and L b22 One of X represents a chain hydrocarbon group having 1 to 6 carbon atoms, and the other represents a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms. 2 represents -O-, -CO-O-, -O-CO-, or -O-CO-O-. * and ** represent binding sites, and ** represents Y b1 where L b21 , X 2 and L b22 The total number of carbon atoms is 12 or less.

[0246] In formula (I-A1), Y b1is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and even more preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, it is more preferable that it is a group represented by the following formulae (Y1) to (Y36). In formulae (Y1) to (Y36), R Yb is a hydrogen atom or Y b1 Among the substituents that the cyclic hydrocarbon group may have, R represents an alkyl group having 1 to 4 carbon atoms. Yc is a hydrogen atom or Y b1 represents a substituent that the cyclic hydrocarbon group may have, and * represents L b2 The 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.

[0247] [ka]

[0248] The anion represented by formula (I-A1) is preferably an anion represented by formulas (I-A1-1) to (I-A1-85) [hereinafter, may be referred to as "anion (I-A1-1)" depending on the formula number.], and more preferably an anion represented by any of formulas (I-A1-1) to (I-A1-4), (I-A1-9), (I-A1-10), (I-A1-24) to (I-A1-33), (I-A1-36) to (I-A1-40), and (I-A1-47) to (I-A1-85).

[0249] [ka]

[0250] [ka]

[0251] [ka]

[0252] 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, a chain hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. A41 Q is a single bond or an alkanediyl group having 1 to 4 carbon atoms. b1 and Q b2 has the same meaning as above.

[0253] Specific examples of the anion represented by formula (I-A1) include the anions described in JP-A-2010-204646. Preferable examples of the anion represented by formula (I-A1) include the anions represented by formulae (Ia-1) to (Ia-70).

[0254] [ka]

[0255] [ka]

[0256] [ka]

[0257] Of these, anions represented by any one of formulae (Ia-1) to (Ia-4), (Ia-7) to (Ia-11), (Ia-14) to (Ia-30), and (Ia-35) to (Ia-70) are preferred.

[0258] (Anion (I-A2)) The anion represented by formula (I-A2) is represented by the following formula:

[0259] [ka]

[0260] [In formula (I-A2), all symbols have the same meaning as above.] In formula (I-A2), L b2 As the hydrocarbon group, within the range permitted by the upper limit of the number of carbon atoms, L of formula (IA) b2 Examples of the hydrocarbon groups are the same as those exemplified in L. b2 The substituents that the hydrocarbon group may have are as follows: b2 Examples of the substituents that may be contained in the hydrocarbon group exemplified above are the same as those shown in the above.

[0261] In formula (I-A2), L b2 is preferably a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and more preferably *-CO-OL b41 -(L b41 is a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms, and -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-. * is SO3 - It represents the bonding site with the benzene ring to which L is attached. b41 is preferably a single bond or a chain hydrocarbon group having 1 to 3 carbon atoms.

[0262] In formula (I-A2), Y b1 As the cyclic hydrocarbon group, within the range permitted by the upper limit of the number of carbon atoms, Y in formula (IA) b1 The cyclic hydrocarbon groups exemplified by Y b1 The substituents which the methyl group and the cyclic hydrocarbon group may have are as exemplified in formula (IA) Y b1 Examples of the substituents that may be contained in the methyl group and the cyclic hydrocarbon group include the same groups as those in the above-mentioned formula (1).

[0263] In formula (I-A2), Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and further 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.

[0264] In formula (I-A2), nb4 is preferably any integer of 1 to 4, more preferably any integer of 1 to 3, further preferably 1 or 2, and further more preferably 2. When nb4 is 1 or 2, -L b2 -Y b1 The bond position of SO3 - It is preferable that the structure shown below is a meta-position substitution on the benzene ring with respect to the bonding position of the above.

[0265] [ka]

[0266] [In the above formula, Lb2 , 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 groups.

[0267] R b1 Examples of the alkyl group having 1 to 6 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 4, and more preferably 1 to 3.

[0268] R b1 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R b1 Examples of the alkyl group in which -CH2- is replaced with -O- or -CO- include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an oxy group, a carbonyl group, etc. Specific examples of these are the same as those mentioned above.

[0269] R b1 are each independently preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), more preferably a fluorine atom, an iodine atom, or an alkyl group having 1 to 3 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), and further preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group, or a methyl group.

[0270] nb3 is preferably an integer of 0 to 3, and more preferably an integer of 0 to 2. In one embodiment, nb3 is preferably 0. In another embodiment, nb3 is preferably 1 or 2. When nb3 is 1, R b1 is preferably a halogen atom, and R b1 is more preferably a fluorine atom or an iodine atom. When nb3 is 2, two R b1 It is preferable that one of R is a halogen atom and the other is a halogen atom or an alkyl group having 1 to 4 carbon atoms. b1 It is more preferable that one of them is a fluorine atom or an iodine atom, and the other is a fluorine atom, an iodine atom, or an alkyl group having 1 to 3 carbon atoms.

[0271] Examples of the anion represented by formula (I-A2) include the following anions. Among them, the anions represented by formulas (I-a2-1) to (I-a2-20) are preferred, and the anions represented by formulas (I-a2-1) to (I-a2-11) and (I-a2-16) to (I-a2-20) are more preferred. The anions of the following formulas (I-a2-1) to (I-a2-20) include some R b1 is omitted, and may contain substituents not shown.

[0272] [ka]

[0273] In another embodiment, AI - The organic anion represented by the formula (I) may be a sulfonylimide anion or a sulfonylmethide anion, - is preferably a sulfonylimide anion or a sulfonylmethide anion (hereinafter sometimes referred to as "anion (IB)") represented by formula (IB).

[0274] (Anion (IB)) The anion represented by formula (IB) is represented by the following formula:

[0275] [ka]

[0276] [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- or -SO2-.

[0277] Y b1 ' represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0278] nb5 represents an integer of 2 or 3. When nb5 is 2, A 1 is a nitrogen atom, and when nb5 is 3, A 1 A is a carbon atom. The groups in the parentheses may be the same or different from each other, and two groups in the parentheses are bonded to form A 1 may form a ring containing the following. In formula (IB), L b2 ′ and Y b1 Examples of the hydrocarbon group, cyclic hydrocarbon group and substituent of L′ are b2 and Y b1 The same groups as those shown below can be mentioned.

[0279] 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 b23 represents a chain hydrocarbon group having 1 to 6 carbon atoms which may contain a fluorine atom. 2and 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 preferable.

[0280] 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- 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- or -SO2-), or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. Specifically, it is more preferably a trifluoromethyl group or a group represented by formulae (Y1) to (Y36) exemplified in formula (I-A1).

[0281] In formula (IB), two -SO2-L b2′ -Y b1′ Together, A 1 When a ring containing the formula (IB) is formed, for example, an anion represented by the formula (IB′) is included.

[0282] [ka]

[0283] [In formula (IB′), A 1 , Y b1 , L b2 and nb5 have the same meaning as in formula (IB). W b4 represents a disulfonylimide ring or disulfonylmethide ring having 2 to 12 carbon atoms which may have a fluorine atom.] Wb4 The disulfonylimide ring or disulfonylmethide 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 replaced with a fluorine atom.

[0284] Examples of the anion represented by formula (IB) include the following. Among these, the anions represented by formulae (I-a3-1) and (I-a3-2) are preferred.

[0285] [ka]

[0286] Specific examples of the salt (I) include salts of any combination of the above-mentioned cations and anions. Specific examples of the salt (I) are shown in the table below. In the table below, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation, and "~" indicates that the salt (I) corresponds to the anion (I). For example, salt (I-1) means a salt consisting of an anion represented by formula (Ia-1) and a cation represented by formula (Ic-1), and represents the salt shown below. Furthermore, salt (I-2) represents a salt consisting of an anion represented by formula (Ia-2) and a cation represented by formula (Ic-1), and salt (I-66) represents a salt consisting of an anion represented by formula (Ia-1) and a cation represented by formula (Ic-2).

[0287] [ka]

[0288] [Table 1] JPEG2025015501000054.jpg226170JPEG2025015501000055.jpg145170

[0289] Among these, the 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-a2-20) with a cation represented by any one of formulas (Ic-1) to (Ic-50).

[0290] <Method for producing salt (I)> The salt (I) can be produced by reacting a salt represented by the formula (Ia) with a salt represented by the formula (Ib) in a solvent.

[0291] [ka]

[0292] [In the formula, all symbols have the same meaning as defined above.] R 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 together 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.

[0293] The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours. Examples of the salt represented by formula (Ib) include salts represented by the following formula: These salts can be easily produced by the same method as that described in JP2011-116747A and JP2016-047815A or by known production methods.

[0294] [ka]

[0295] [ka]

[0296] [ka]

[0297] In the salt (Ia), R 1A But *-OL 10 -CO-OR 10 The salt represented by formula (I-a1) can be produced by reacting a salt represented by formula (Ic) with a compound represented by formula (Id) in a solvent in the presence of a base catalyst.

[0298] [ka]

[0299] [In the formula, all symbols have the same meaning as defined above.] Examples of the base include potassium carbonate, potassium iodide, pyridine, triethylamine and the like.

[0300] Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours.

[0301] Examples of the compound represented by formula (Id) include the compounds represented by the following formulas, which are readily available on the market and can also be readily produced by known methods.

[0302] [ka]

[0303] The salt represented by formula (Ic) can be prepared by passing the salt represented by formula (Ic') through an ion exchange resin.

[0304] [ka]

[0305] [In the formula, all symbols have the same meaning as defined above.] The ion exchange resin may be, for example, ion exchange resin (No. 6, 100-200 mesh, manufactured by Wako Pure Chemical Industries, Ltd.).

[0306] The solvent may be methanol or the like. When X is a sulfur atom, the salt represented by formula (Ic') can be produced by reacting a compound represented by formula (Ie) with a compound represented by formula (If) in the presence of trifluoroacetic anhydride and trifluoromethanesulfonic acid in a solvent, followed by treatment with a base.

[0307] [ka]

[0308] [In the formula, all symbols have the same meaning as defined above.] Examples of the solvent include chloroform, monochlorobenzene, and acetonitrile. The reaction temperature is usually 15° C. to 100° C., and the reaction time is usually 0.5 to 24 hours.

[0309] Examples of the compound represented by formula (Ie) include compounds represented by the following formula, and are readily available on the market.

[0310] [ka]

[0311] Examples of the compound represented by formula (If) include compounds represented by the following formula, and are readily available on the market.

[0312] [ka]

[0313] When X is an iodine atom, the salt represented by formula (Ic) can be produced by reacting a compound represented by formula (Ig) with a compound represented by formula (If) in the presence of potassium peroxymonosulfate and sulfuric acid in a solvent, followed by treatment with hydrochloric acid.

[0314] [ka]

[0315] [In the formula, all symbols have the same meaning as defined above.] Examples of the solvent include chloroform, monochlorobenzene, and acetonitrile. The reaction temperature is usually 15° C. to 100° C., and the reaction time is usually 0.5 to 24 hours.

[0316] Examples of the compound represented by formula (Ig) include compounds represented by the following formula, and are readily available on the market.

[0317] [ka]

[0318] In the salt (Ia), R 1A But *-OR 10 The salt represented by formula (I-a2) can be produced by reacting a salt represented by formula (Ic) with a compound represented by formula (I-d1) in a solvent in the presence of a base catalyst.

[0319] [ka]

[0320] [In the formula, all symbols have the same meanings as defined above. X X represents a hydroxy group or a chlorine atom. Examples of the base include potassium carbonate, potassium iodide, pyridine, triethylamine, potassium hydroxide, sodium hydroxide and the like.

[0321] Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water. The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours.

[0322] Examples of compounds represented by formula (I-d1) include the compounds represented by the following formulas, which are readily available on the market or can be readily produced by known methods.

[0323] [ka]

[0324] In the salt (Ia), R 1A But, *-O-CO-OR 10 The salt represented by formula (I-a3) can be produced by reacting a salt represented by formula (Ic) with a compound represented by formula (I-d2) in a solvent in the presence of carbonyldiimidazole.

[0325] [ka]

[0326] [In the formula, all symbols have the same meaning as defined above.] Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water.

[0327] The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours. Compounds represented by formula (I-d2) include corresponding compounds among compounds represented by formula (I-d1), and are easily available on the market or can be easily produced by known production methods.

[0328] In the salt (Ia), R 1A But, *-O-CO-R 10 The salt represented by formula (I-a4) can also be produced by reacting a salt represented by formula (Ic) with a compound represented by formula (I-d3) in a solvent in the presence of a base catalyst.

[0329] [ka]

[0330] Examples of the base include potassium carbonate, potassium iodide, pyridine, triethylamine and the like. Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, and water.

[0331] The reaction temperature is usually 15° C. to 80° C., and the reaction time is usually 0.5 to 24 hours. Examples of the compound represented by formula (I-d3) include the compounds represented by the following formulas, and are readily available on the market.

[0332] [ka]

[0333] In the salt (Ia), R 1B But *-OL 10 -CO-OR 10 , *-OR 10 OR*-O-CO-OR 10 and a salt R 1A and R 1B But *-OL10 -CO-OR 10 , *-OR 10 OR*-O-CO-OR 10 The salts each having the formula R 1A *-OL 10 -CO-OR 10 , *-OR 10 OR*-O-CO-OR 10 In the reaction scheme used in the example of the production method of the salt, the salt represented by formula (1-c) can be replaced with a salt represented by the following formula (Ic'') or formula (Ic''').

[0334] [ka]

[0335] <Acid generator> The acid generator of the present invention is an acid generator containing a salt (I). It may contain one type of salt (I) or may contain two or more types of salt (I).

[0336] 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)", but excluding salt (I).) The compound (B) may be used alone or in combination of two or more kinds.

[0337] <Compound (B)> The compound (B) may be either a nonionic compound or an ionic compound. Examples of the nonionic compound include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), and the like. Examples of the ionic compound include onium salts containing onium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Examples of the anion of the onium salt include sulfonate anion, sulfonylimide anion, sulfonylmethide anion, and carboxylate anion.

[0338] Compound (B) may be a compound that generates an acid by radiation, as described in JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Pat. No. 3,779,778, U.S. Pat. No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc. Compounds produced by known methods may also be used. Compound (B) may be used alone or in combination of two or more.

[0339] Compound (B) is preferably a salt represented by formula (B1) (hereinafter sometimes referred to as "compound (B1)" or "salt (B1)", except for salt (I)) or a salt represented by formula (B2) (hereinafter sometimes referred to as "compound (B2)" or "salt (B2)", except for salt (I)). The anion in the salt represented by formula (B1) is more preferably an anion represented by formula (B1-1) (hereinafter sometimes referred to as "anion (B1-1)") or an anion represented by formula (B1-2) (hereinafter sometimes referred to as "anion (B1-2)").

[0340] [ka]

[0341] [In formula (B1), Z1 + The symbols other than the above have the same meaning as in formula (IA). Z1 + represents an organic cation, except for the cation represented by formula (IC).

[0342] [ka]

[0343] [In formula (B1-1), all symbols have the same meaning as in formula (I-A1)]

[0344] [ka]

[0345] [In formula (B1-2), all symbols have the same meaning as in formula (I-A2)]

[0346] [ka]

[0347] [In formula (B2), Z2 + The symbols other than the above have the same meaning as in formula (IB). Z2 + represents an organic cation, except for the cation represented by formula (IC). L in formula (B1) b1 , L b2 , Y b1 and nb1 are L in the above formula (IA), b1 , L b2 , Y b1 and nb1, and the like.

[0348] Q in formula (B1-1) b1 , Q b2 , Q b3 , Q b2 , z1, X1 , L b3 , L b2 , Y b1 and nb2 are each the Q b1 , Q b2 , Q b3 , Q b2 , z1, X 1 , L b3 , L b2 , Y b1 and nb2, and the like.

[0349] Examples of the anion represented by formula (B1-1) include the same anion as represented by formula (I-A1). L in formula (B1-2) b2 , Y b1 , R b1 , nb4 and nb3 are each L in the above formula (I-A2). b2 , Y b1 , R b1 , nb4 and nb3, and the like.

[0350] Examples of the anion represented by formula (B1-2) include the same anion as represented by formula (I-A2). A in formula (B2) 1 , L b2 ′, Y b1 ' and nb5 are each A in the above formula (IB). 1 , L b2 ′, Y b1 ' and nb5, and the like.

[0351] The anion in the salt represented by formula (B2) may be the same as the anion represented by formula (IB). In another embodiment of compound (B), a salt in which the anion of the salt represented by formula (B1) is replaced with a carboxylate anion is also preferably used as compound (B).

[0352] Examples of carboxylate anions include the following:

[0353] [ka]

[0354] Z1 + and Z2 + Examples of the organic cation include organic onium cation, organic sulfonium cation, organic iodonium cation, organic ammonium cation, benzothiazolium cation, and organic phosphonium cation. Among these, organic sulfonium cation and organic iodonium cation are preferred, and arylsulfonium cation or aryl iodonium cation 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). However, Z1 + and Z2 + The organic cations in the formula (IC) are excluded.

[0355] [ka]

[0356] [In formulas (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.

[0357] R b4 and R b5 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-.

[0358] 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.

[0359] m2 and n2 each independently represent an integer of 0 to 5. When m2 is 2 or more, multiple R b7 may be the same or different, and when n2 is 2 or more, multiple R b8 may be the same or different.

[0360] 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 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-.

[0361] 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 an open 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, a hydrogen atom contained in the open chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and 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.

[0362] R b11 and R b12 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-.

[0363] R b13 ~R b18 and R b21 ~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.

[0364] R b13 and R b14 and R b21 and R b22 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-.

[0365] 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.

[0366] 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 b17are the same or different, and when t2 is 2 or more, multiple R b18 are the same or different.

[0367] o21, p22, q23, r24, t25 and s26 each independently represent an integer of 0 to 4. When o21 is 2 or more, multiple R b21 are the same or different, and when p22 is 2 or more, multiple R b22 are the same or different, and when q23 is 2 or more, multiple R b23 are the same or different. When r24 is 2 or more, multiple R b24 are the same or different, and when t25 is 2 or more, multiple R b25 are the same or different, and when s26 is 2 or more, multiple R b26 are the same or different.

[0368] 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, providing that 0≦u4+o21≦5 and 0≦u5+p22≦5 are satisfied.

[0369] When u3, u4, and u5 each are 2 or more, the groups in the multiple 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 them 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.

[0370] 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.

[0371] 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.

[0372] 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:

[0373] [ka]

[0374] 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.

[0375] The fluorinated alkyl group refers to an alkyl group having 1 to 12 carbon atoms and a fluorine atom, and examples of such groups 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 further preferably 1 to 4.

[0376] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. 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 with 1 to 18 carbon atoms (tolyl group, xylyl group, cumenyl group, mesityl group, p-ethylphenyl group, p-tert-butylphenyl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.) and aromatic hydrocarbon groups having an alicyclic hydrocarbon group with 3 to 18 carbon atoms (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.). When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group with 1 to 18 carbon atoms and an alicyclic hydrocarbon group with 3 to 18 carbon atoms are preferred.

[0377] An example of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group is a p-methoxyphenyl group. Examples of the chain hydrocarbon group in which a hydrogen atom has been substituted with an aromatic hydrocarbon group include aralkyl groups such as a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.

[0378] 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.

[0379] 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.

[0380] 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.

[0381] R b4 and R b5 The ring formed by bonding to each other together with the sulfur atom to which they are bonded may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include rings having 3 to 18 carbon atoms, and preferably rings having 4 to 18 carbon atoms. Examples of the ring containing a sulfur atom include 3-membered to 12-membered rings, and preferably 3-membered to 7-membered rings, and examples of such rings include the following rings. * represents a bonding site.

[0382] [ka]

[0383] R 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-membered to 12-membered ring, preferably a 3-membered to 7-membered ring. For example, it may be a thiolane-1-ium ring (tetrahydrothiophenium ring), a thiane-1-ium ring, a 1,4-oxathiane-4-ium ring, etc.

[0384] R b11 and R b12The ring formed by combining with may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. The ring may be a 3-membered to 12-membered ring, preferably a 3-membered to 7-membered ring. Examples of the ring include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

[0385] R b27 ~R b29 Examples 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, R c30 represents an acid labile group.

[0386] R b27 ~R b29 Examples of the acid labile group include groups represented by formula (1) or formula (2) exemplified in this specification. Among the cations (b2-1) to (b2-5), the cation (b2-1), the cation (b2-4) or the cation (b2-5) is preferred.

[0387] Examples of the cation (b2-1) include the following cations.

[0388] [ka]

[0389] Examples of the cation (b2-2) include the following cations.

[0390] [ka]

[0391] Examples of the cation (b2-3) include the following cations.

[0392] [ka]

[0393] Examples of the cation (b2-4) include the following cations.

[0394] [ka]

[0395] Examples of the cation (b2-5) include the following cations.

[0396] [ka]

[0397] Compound (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, which can be combined arbitrarily. The acid generator (B) is preferably a combination of an anion 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), and (I-a3-1) to (I-a3-20) and a cation (b2-1), a cation (b2-2), a cation (b2-3), a cation (b2-4), or a cation (b2-5).

[0398] Compound (B) is preferably one represented by formula (B1-1) to formula (B1-105), formula (B2-1) to formula (B2-20), and formula (B3-1) to formula (B3-28). Among them, one containing an arylsulfonium cation is preferred, and one represented by formula (B1-1) to formula (B1-3), formula (B1-5) to formula (B1-7), formula (B1-11) to formula (B1-14), formula (B1-20) to formula (B1-26), formula (B1-29), formula (B1-31) to formula (B1-105), formula (B2-1) to formula (B2-20), and formula (B3-1) to formula (B3-28) is particularly preferred.

[0399] [ka]

[0400] [ka]

[0401] [ka]

[0402] [ka]

[0403] [ka]

[0404] [ka]

[0405] [ka]

[0406] [ka]

[0407] When the acid generator contains salt (I) and compound (B), the content ratio of salt (I) to compound (B) (mass ratio; salt (I):compound (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.

[0408] <Resist Composition> The resist composition of the present invention contains an acid generator containing a salt (I). The resist composition of the present invention may further contain a resin. The resin may be a resin containing a structural unit having an acid labile group (hereinafter, sometimes referred to as "resin (A)") and / or a resin other than resin (A). Here, the "acid labile group" means a group that has a leaving group and is released by contact with an acid, converting the structural unit into a structural unit having a hydrophilic group (e.g., a hydroxyl group or a carboxyl group).

[0409] The resist composition of the present invention preferably further contains a quencher such as a salt that generates an acid having a weaker acidity than the acid generated from the acid generator (hereinafter may be referred to as "quencher (C)"), and preferably contains a solvent (hereinafter may be referred to as "solvent (E)").

[0410] <Acid generator> In the resist composition of the present invention, the total content of the acid generators is, for example, 1% by mass to 85% by mass, may be 1% by mass to 65% by mass, preferably 1% by mass to 45% by mass, more preferably 1% by mass to 40% by mass, and even more preferably 3% by mass to 35% by mass. The content of the salt (I) is, for example, 1% by mass to 85% by mass, may be 1% by mass to 65% by mass, preferably 1% by mass to 50% by mass, more preferably 1% by mass to 40% by mass, and even more preferably 3% by mass to 35% by mass, based on the solid content of the resist composition. In addition, when the resin (A) is contained, the total content of the acid generators is, for example, 1 part by mass to 45 parts by mass, more preferably 1 part by mass to 40 parts by mass, and even more preferably 3 parts by mass to 40 parts by mass, based on 100 parts by mass of the resin (A) described below.

[0411] <Resin (A)> Resin (A) contains a structural unit having an acid labile group (hereinafter may be referred to as "structural unit (a1)"). Resin (A) preferably further contains a structural unit other than the structural unit (a1). Examples of structural units other than the structural unit (a1) include structural units not having an acid labile group (hereinafter may be referred to as "structural unit (s)"), structural units other than the structural unit (a1) and the structural unit (s) (for example, a structural unit having a halogen atom (hereinafter may be referred to as "structural unit (a4)") described below, a structural unit having a non-leaving hydrocarbon group (hereinafter may be referred to as "structural unit (a5)") described below, and other structural units derived from monomers known in the art.

[0412] <Structural unit (a1)> The structural unit (a1) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as "monomer (a1)").

[0413] 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)).

[0414] [ka]

[0415] [In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, or R a1 and R a2 are bonded to each other to form, together with the carbon atom to which they are bonded, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom.

[0416] ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * denotes a binding site.]

[0417] [ka]

[0418] [In formula (2), R a1′ and R a2′ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a3′ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2′ and R a3′ are bonded to each other to form, together with the carbon atom to which they are bonded and X, a heterocyclic group having 3 to 20 carbon atoms, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom.

[0419] X represents an oxygen atom or a sulfur atom. na′ represents 0 or 1. * denotes a binding site.] R a1 , Ra2 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.

[0420] R a1 , R a2 and R a3 Examples of the alkenyl group in include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, and a nonenyl group.

[0421] R a1 , R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site). R a1 , R a2 and R a3 The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms.

[0422] [ka]

[0423] R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group in include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and an alicyclic hydrocarbon group are combined (for example, an alkylcycloalkyl group or a cycloalkylalkyl group such as a methylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, or a norbornylethyl group), an aralkyl group such as a benzyl group, an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, or the like), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, or the like), and an aryl-cycloalkyl group such as a phenylcyclohexyl group.

[0424] Preferably, ma is 0 and na is 1. R a1 and R a2 When they are bonded to each other to form an alicyclic hydrocarbon group, -C(R a1 )(R a2 )(R a3 ) includes the following groups. The alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-.

[0425] [ka]

[0426] 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.

[0427] Alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups are R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a2′ and R a3′ When they are bonded to each other to form a heterocyclic group together with the carbon atom to which they are bonded and X, -C(R a1′ )(R a2′ )-XR a3′ Examples of the group include the following: * represents a binding site.

[0428] [ka]

[0429] R 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 which may be contained includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0430] Examples of the group (1) include the following groups. In formula (1), R a1 , R a2 and R a3 is an alkyl group, ma = 0, and na = 1. As the group, a tert-butoxycarbonyl group is preferable.

[0431] In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, R a3 is an alkyl group, ma=0, and na=1. In formula (1), R a1 and R a2 are each independently an alkyl group; R a3 is an adamantyl group, ma=0, and na=1.

[0432] Specific examples of the group (1) include the following groups: * represents a binding site.

[0433] [ka]

[0434] [ka]

[0435] Specific examples of the group (2) include the following groups: * represents a bonding site.

[0436] [ka]

[0437] The monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid labile group. Of the (meth)acrylic monomers having an acid labile group, preferred are those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms. By using a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group in a resist composition, the resolution of the resist pattern can be improved.

[0438] Examples of the structural unit derived from the (meth)acrylic monomer having the group (1) include a structural unit represented by formula (a1-0) (hereinafter, sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter, sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter, sometimes referred to as structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1) and the structural unit (a1-2), more preferably at least one or two structural units selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more.

[0439] [ka]

[0440] [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or *-O-(CH2) k1 represents --CO--O--, k1 represents an integer of 1 to 7, and * represents a bonding site with --CO--.

[0441] R a01 , R a4 and R a5 each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 , R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, and the alkyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom.

[0442] R a6 and R a7each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom.

[0443] m1′ represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. R a01 , R a4 and R a5 The halogen atom in the formula (I) includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0444] R a01 , R a4 and R a5 Examples of the alkyl group which may have a halogen atom in the above formula include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. The alkyl group is preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0445] R a01 , R a4 and R a5 is preferably a hydrogen atom or a methyl group, and more preferably a methyl group. L a01 , L a1and 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.

[0446] 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.

[0447] R a02 , R a03 , and R a04 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

[0448] 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.

[0449] 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.

[0450] 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 , Ra03 , 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.

[0451] 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.

[0452] R a02 and R a03 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group which may have a halogen atom.

[0453] R a04 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group which may have a halogen atom.

[0454] 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.

[0455] 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.

[0456] n1' is preferably 0 or 1. 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. 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.

[0457] [ka]

[0458] [ka]

[0459] Examples of the structural unit (a1-1) include structural units derived from monomers described in JP-A-2010-204646. Among them, structural units represented by any one of formulas (a1-1-1) to (a1-1-7) and R in the structural unit (a1-1) in the structural unit (a1-1) are a4 In the above formula (a1-1-1), a methyl group is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. In the above formula (a1-1-2), a methyl group is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. In the above formula (a1-1-3), a methyl group is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. In the above formula (a1-1-4), a structural unit is more preferred.

[0460] [ka]

[0461] The structural unit (a1-2) includes a structural unit represented by any one of formulas (a1-2-1) to (a1-2-20) and R a5 and structural units in which a methyl group corresponding to the formula (a1-2-2), (a1-2-5), (a1-2-6), and (a1-2-10) to (a1-2-20) are replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group.

[0462] [ka]

[0463] 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 units is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A). Also, 95 mol% or less is included, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, 10 to 95 mol% is included, 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%.

[0464] When the resin (A) contains the structural unit (a1-0), the content thereof is 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, even more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, and even more preferably 35 mol% or more, based on the total structural units of the resin (A). Also, the content is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less, and even more preferably 60 mol% or less. Specifically, the content is 5 to 80 mol%, preferably 5 to 75 mol%, and more preferably 10 to 70 mol%.

[0465] When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these units is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A). Also, 95 mol% or less is included, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, 10 to 95 mol% is included, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, even more preferably 20 to 80 mol%, and even more preferably 20 to 75 mol%.

[0466] An example of the structural unit (a1) having a group (2) is a structural unit represented by formula (a1-4) (hereinafter, sometimes referred to as "structural unit (a1-4)").

[0467] [ka]

[0468] [In formula (a1-4), R a1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.

[0469] 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.

[0470] 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.

[0471] 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 a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -CO- to which they are bonded, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-.

[0472] na1 represents an integer of 1 to 5, and when na1 is 2 or more, the groups in the multiple parentheses may be the same or different. na11 represents an integer of 0 to 4. When na11 is 2 or more, multiple R a17may be the same or different from each other.

[0473] mc represents an integer from 0 to 2. R a1 and R a17 Examples of the halogen atom in include a fluorine atom, a chlorine atom, and a bromine atom.

[0474] R a1 and R a17 Examples of the alkyl group having 1 to 6 carbon atoms, which may have a halogen atom, include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2.

[0475] R a1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and further preferably a hydrogen atom or a methyl group. R a17 Examples of the alkoxy group in include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 4, and more preferably 1 to 3. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group.

[0476] R a17In the above, examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group.

[0477] R a17 In the above, examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group.

[0478] R a17 In the above formula, examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group.

[0479] R a17 In the above formula, examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group.

[0480] R a17is 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.

[0481] A a11 Examples of the alkanediyl group include straight-chain alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl groups. Examples of branched alkanediyl groups include branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, and undecane-1,10-diyl group. The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, still more preferably 1 to 3, and even more preferably 1 or 2. In addition, A a11 is also preferably a methylene group or an ethylene group.

[0482] R a18 Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. A a11 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a18When the alkanediyl group is replaced by, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the alkanediyl group.

[0483] A a11 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a18 Groups substituted with - include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), a carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), an oxy group (a group in which -CH2- in a methylene group is replaced with -O-), an amino group (a group in which -CH2- in a methyl group is replaced with -NR a18 -), alkoxy group (a group in which -CH2- at any position in the alkyl group is replaced with -O-), alkoxycarbonyl group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -O-CO-), alkylcarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -CO-), alkylamino group (a group in which -CH2- at any position in the alkyl group is replaced with -NR a18 -), peptide group (the -CH2-CH2- in the ethylene group is replaced by -CO-NR a18-), alkanediyloxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -O-), alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -CO-), alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -CO-O-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -SO2-), an alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -S-), an alkanediylamino group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -NR a18 These substituted groups include those exemplified in this specification, within the range permitted by the upper limit of the carbon number.

[0484] The alkylamino group includes alkylamino groups having 1 to 11 carbon atoms, such as a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, an octylamino group, etc. The number of carbon atoms in the alkylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0485] The alkanediylamino group includes an alkanediylamino group having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, etc. The number of carbon atoms in the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0486] For example, A a11 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a18Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, *-CO-OA a12 -CO-O-, *-O-CO-A a12 -O-, *-OA a12 -CO-O-, *-CO-OA a12 -O-CO-, *-O-CO-A a12 -O-CO-, *-CO-NR a18 Among them, *-CO-O- and *-CO-OA a12 -CO-O-, *-OA a12 -CO-O-, *-CO-NR a18 - is preferred, where A a12 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents R a1 A represents the bonding site with the carbon atom to which it is attached. a12 The alkanediyl group of A is as follows, within the upper limit of the carbon number. a11 Examples of the alkanediyl groups include those shown above.

[0487] 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.

[0488] na1 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na11 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and further preferably 0 or 1.

[0489] 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 consisting of a combination thereof.

[0490] Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site):

[0491] [ka]

[0492] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined (e.g., alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, and norbornylethyl group), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), and aryl-cycloalkyl groups such as phenylcyclohexyl group. In particular, R a36 Examples of the alkyl group include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these groups.

[0493] R a35 and R a36Examples of the divalent hydrocarbon group having 2 to 20 carbon atoms that is formed by bonding together with the -CO- to which they are bonded include the following groups. * represents a bonding site, and one of the groups is R a34 This is the binding site for

[0494] [ka]

[0495] R 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.

[0496] R a36 The hydrocarbon group in R is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. a36 The alkyl group and the alicyclic hydrocarbon group in R are preferably unsubstituted. a36 The aromatic hydrocarbon group in is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0497] -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.

[0498] -X a1 -OC(R a34 )(R a35 )-OR a36 In the case of a benzene ring, A a11In particular, it is preferable that at least one of them is bonded to the ortho-position or the para-position, and it is more preferable that it is bonded to the para-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 2-position, it may be bonded to any of the 1-position and the 3-8-positions. a11 When the bonding position of A is the 1st position, at least one of them is preferably bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. a11 When the bonding position is the 2-position, it is preferably bonded to the 4- to 7-positions, and more preferably bonded to the 5- or 6-position.

[0499] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP 2010-204646 A. Preferred are the structural units represented by formulas (a1-4-1) to (a1-4-42) and R in the structural unit (a1-4) 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), respectively.

[0500] [ka]

[0501] When the resin (A) contains the structural unit (a1-4), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total of all structural units in the resin (A). Also, the content is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 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 even more preferably 20 to 65 mol%.

[0502] An example of a structural unit derived from a (meth)acrylic monomer having the group (2) is a structural unit represented by formula (a1-5) (hereinafter, may be referred to as "structural unit (a1-5)").

[0503] [ka]

[0504] [In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom.

[0505] Z a1 is a single bond or -(CH2) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 It represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-.

[0506] s1 represents an integer of 1 to 3. s1′ represents an integer of 0 to 3. R a8 Examples of the halogen atom in include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Of these, a fluorine atom is preferred.

[0507] R a8 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, and a perfluorohexyl group.

[0508] 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.

[0509] L 52 and L 53 Of these, it is preferred that one is -O- and the other is -S-. It is preferable that s1 is 1. s1' is preferably an integer of 0 to 2.

[0510] Z a1 is preferably a single bond or -CH2-CO-O-. Examples of the structural unit (a1-5) include structural units derived from monomers described in JP 2010-61117 A. Among them, the structural units represented by formulae (a1-5-1) to (a1-5-4) are preferred, and the structural unit represented by formula (a1-5-1) or (a1-5-2) is more preferred.

[0511] [ka]

[0512] When the resin (A) contains the structural unit (a1-5), the content thereof is 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, even more preferably 10 mol% or more, even more preferably 20 mol% or more, and even more preferably 25 mol% or more, based on the total structural units of the resin (A). Also, the content is 80 mol% or less, preferably 70 mol% or less, more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 45 mol% or less, even more preferably 40 mol% or less, and even more preferably 30 mol% or less. Specifically, the content is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, even more preferably 5 to 40 mol%, and even more preferably 5 to 30 mol%.

[0513] An example of the structural unit (a1) having a group (1) is a structural unit represented by formula (a1-6) (hereinafter, sometimes referred to as "structural unit (a1-6)").

[0514] [ka]

[0515] [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.

[0516] 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.

[0517] X a61 is a single bond, -CO-O-* or -CO-NR 5 -*, where * represents the bonding site with Ar, and R 5 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X a62 is a single bond, *-OL a61 -or*-CO-OL a62 -, * represents the bonding site with Ar, L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms.

[0518] Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.] R a61 Examples of the halogen atom in include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Of these, a fluorine atom is preferred.

[0519] R a61 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in the formula (I) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, and a perfluorohexyl group.

[0520] R a61 is preferably a hydrogen atom, a methyl group, or a trifluoromethyl group. R a62 , R a63 and R a64 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and further preferably a methyl group or an ethyl group.

[0521] R a62 , R a63 and R a64 The cyclic hydrocarbon group in the formula (I) includes an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, and a norbornyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, and more preferably 3 to 12.

[0522] 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.

[0523] R a62 and R a63 Examples of the ring formed by bonding with each other include an adamantane ring, a cyclopentane ring, and a cyclohexane ring. a62 and R a63 When they are bonded to each other to form a ring, -C(Ra62 )(R a63 )(R a64 ) includes the following groups. * represents a bonding site with an oxygen atom. The ring preferably has 3 to 16 carbon atoms, more preferably 3 to 12 carbon atoms.

[0524] [ka]

[0525] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group.

[0526] L a61 and L a62 is preferably each independently a methylene group or an ethylene group. X a61 is preferably a single bond or -CO-O-*, and more preferably a single bond.

[0527] X a62 is preferably a single bond or *-OL a61 -, and more preferably a single bond. Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms for Ar include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, and a phenanthrylene group.

[0528] 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.

[0529] Examples of the halogen atom include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and further preferably a methyl group.

[0530] Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, and a hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and further preferably a methoxy group.

[0531] Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and further preferably a methoxymethyl group.

[0532] Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group.

[0533] Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, a butyryl group, etc. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group.

[0534] Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group.

[0535] 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.

[0536] Ar is preferably a phenylene group which may have a substituent, and more preferably a phenylene group which may have a hydroxy group. Examples of the structural unit (a1-6) include structural units represented by formulae (a1-6-1) to (a1-6-44), preferably structural units represented by formulae (a1-6-1) to (a1-6-9), more preferably structural units represented by formulae (a1-6-1), (a1-6-2), (a1-6-4), (a1-6-5), (a1-6-7) or (a1-6-8), and even more preferably structural units represented by formulae (a1-6-1) or (a1-6-2).

[0537] [ka]

[0538] [ka]

[0539] In the structural units represented by formulae (a1-6-1) to (a1-6-9), (a1-6-16) to (a1-6-21), (a1-6-28) to (a1-6-30), and (a1-6-37) to (a1-6-44), R a61 In the structural units represented by formulae (a1-6-10) to (a1-6-15), (a1-6-22) to (a1-6-27), and (a1-6-31) to (a1-6-36), R a61 The structural unit (a1-6) also includes 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 the like.

[0540] When the resin (A) contains the structural unit (a1-6), the content thereof is 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, even more preferably 10 mol% or more, still more preferably 20 mol% or more, even more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on the total structural units of the resin (A). Also, the content is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, the content is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 65 mol%.

[0541] Further, examples of the structural unit (a1) include the following structural units.

[0542] [ka]

[0543] When the resin (A) contains the structural units represented by the formulas (a1-3-1) to (a1-3-7), the content of the structural units is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A). The content is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 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%.

[0544] Further, examples of the structural unit (a1) include the following structural units.

[0545] [ka]

[0546] When the resin (A) contains the structural units represented by the formulae (a1-7-1) to (a1-7-3), the content of the structural units is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total structural units of the resin (A). The content is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, the content is preferably 10 to 60 mol%, more preferably 15 to 55 mol%, more preferably 20 to 50 mol%, even more preferably 20 to 45 mol%, and particularly preferably 20 to 40 mol%.

[0547] Structural unit(s) The structural unit (s) is derived from a monomer having no acid labile group (hereinafter, may be referred to as "monomer (s)"). As the monomer from which the structural unit (s) is derived, a monomer having no acid labile group known in the resist field can be used.

[0548] The structural unit (s) preferably has a hydroxy group, a carboxy group, or a lactone ring. If a resin containing a structural unit having a hydroxy group or a carboxy group and no acid labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and no acid labile group (hereinafter sometimes referred to as "structural unit (a3)") is used in the resist composition of the present invention, the resolution of the resist pattern and adhesion to the substrate can be improved. In addition to the above-mentioned structural units, the structural unit (s) may also include a structural unit having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"), a structural unit having a sultone structure (hereinafter sometimes referred to as "structural unit (a6)"), or a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)").

[0549] <Structural unit (a2)> The structural unit (a2) is a structural unit represented by formula (a2) and has an alcoholic hydroxy group, a phenolic hydroxy group, a carboxy group, or the like.

[0550] [ka]

[0551] [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.

[0552] 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.

[0553] R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. L a21represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms, the hydrocarbon group optionally having a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-.

[0554] L a22 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms which may have a fluorine atom, and -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-.

[0555] na2 represents an integer of 1 to 5, and when na2 is 2 or more, a plurality of L a22 may be the same or different. R a2 Examples of the halogen atom in include a fluorine atom, an iodine atom, a chlorine atom, and a bromine atom.

[0556] R a2 Examples of the alkyl group having 1 to 6 carbon atoms, which may have a halogen atom, include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2.

[0557] R a2 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and further preferably a hydrogen atom or a methyl group. A a21Examples of the alkanediyl group include straight-chain alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl groups. branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, and undecane-1,10-diyl group.

[0558] The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, still more preferably 1 to 3, and still more preferably 1 or 2. In addition, Aa21 is also preferably a methylene group or an ethylene group.

[0559] R a28 Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group. A a21 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 When it is replaced with -, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the alkanediyl group.

[0560] A a21 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a28Groups substituted with - include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), a carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), an oxy group (a group in which -CH2- in a methylene group is replaced with -O-), an amino group (a group in which -CH2- in a methyl group is replaced with -NR a28 -), alkoxy group (a group in which -CH2- at any position in the alkyl group is replaced with -O-), alkoxycarbonyl group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -O-CO-), alkylcarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -CO-), alkylamino group (a group in which -CH2- at any position in the alkyl group is replaced with -NR a28 -), peptide group (the -CH2-CH2- in the ethylene group is replaced by -CO-NR a28 -), alkanediylamino group (wherein any -CH- at any position in the alkanediyl group is replaced by -NR a28 These substituted groups include those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0561] The alkylamino group includes alkylamino groups having 1 to 11 carbon atoms, such as a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, an octylamino group, etc. The number of carbon atoms in the alkylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0562] The alkanediylamino group includes an alkanediylamino group having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, etc. The number of carbon atoms in the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, further preferably 1 to 4, and further more preferably 1 to 3.

[0563] Among them, A a21 The -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, *-CO-OA a22 -CO-O-, *-O-CO-A a22 -O-, *-OA a22 -CO-O-, *-CO-OA a22 -O-CO-, *-O-CO-A a22 -O-CO-, *-CO-NR a28 Among them, *-CO-O- and *-CO-OA a22 -CO-O-, *-OA a22 -CO-O-, *-CO-NR a28 - is preferred, where A a22 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents R a2 A represents the bonding site with the carbon atom to which it is attached. a22 The alkanediyl group of A is as follows, within the upper limit of the carbon number. a21 Examples of the alkanediyl groups include those shown above.

[0564] 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.

[0565] L a21The hydrocarbon group in is a (na2+1)-valent hydrocarbon group, and examples of such cyclic hydrocarbon groups include linear or branched chain hydrocarbon groups, monocyclic or polycyclic (including spiro rings, fused rings or bridged rings) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may be groups formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group).

[0566] L a21 Examples of the chain hydrocarbon group include divalent to hexavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, an alkanepentyl group, and an alkanehexyl group.

[0567] Examples of the alkanediyl group include A a21 Examples of the alkanediyl groups include those shown above. Examples of the alkanetriyl group include a methanetriyl group, an ethanetriyl group, a propanetriyl group, a butanetriyl group, a pentanetriyl group, a hexanetriyl group, a heptanetriyl group, an octanetriyl group, a nonanetriyl group, a decanetriyl group, an undecanetriyl group, a dodecanetriyl group, a tridecanetriyl group, a tetradecanetriyl group, a pentadecanetriyl group, a hexadecanetriyl group, and a heptadecanetriyl group.

[0568] 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.

[0569] Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 10, still more preferably 1 to 9, even more preferably 1 to 8, even more preferably 1 to 6, even more preferably 1 to 5, and particularly preferably 1 to 4.

[0570] L a21 Examples of the monocyclic and polycyclic alicyclic hydrocarbon groups in the formula (I) include the following alicyclic hydrocarbon groups: The binding site may be any position.

[0571] [ka]

[0572] For example, there can be mentioned divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkanepentyl group, and a cycloalkanehexyl group.

[0573] 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.

[0574] Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 18 carbon atoms, further preferably 3 to 16 carbon atoms, and further preferably 3 to 12 carbon atoms.

[0575] L a21 Examples of the aromatic hydrocarbon group in include divalent to hexavalent aromatic hydrocarbon groups such as an arylene group, an arenetriyl group, an arenettetrayl group, an arenetyl group, and an arenethexyl group.

[0576] Specific examples of aromatic hydrocarbon groups include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, a benzenetriyl group, a naphthalenetriyl group, an anthracenetriyl group, a biphenylenetriyl group, a phenanthrenetriyl group, a benzenetetrayl group, a naphthalenetetrayl group, an anthracenetetrayl group, a biphenylenetetrayl group, and a phenanthrenetetrayl group.

[0577] Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The aromatic hydrocarbon group preferably has 6 to 20 carbon atoms, more preferably 6 to 18 carbon atoms, further preferably 6 to 14 carbon atoms, and further preferably 6 to 10 carbon atoms.

[0578] Examples of groups that combine two or more of these groups include a group that combines an alicyclic hydrocarbon group with a chain hydrocarbon group, a group that combines an aromatic hydrocarbon group with a chain hydrocarbon group, a group that combines an alicyclic hydrocarbon group with an aromatic hydrocarbon group, and a group that combines an alicyclic hydrocarbon group with a chain hydrocarbon group and an aromatic hydrocarbon group. In the combination, two or more of each of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may be combined. In addition, when any of the groups is A a21 Or L a22 may be bound to

[0579] Examples of groups in which -CH2- in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkylthio group (a group in which -CH2- at any position in an alkyl group is replaced by -S-), and a group in which -CH2-CH2- at any position in the alkyl group is replaced with -O-CO-), an alkoxycarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -O-CO-), an alkylsulfonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -SO2-), an alkylcarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -CO-O-), an oxy group (a group in which -CH2- in a methylene group is replaced with -O- a carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), a thio group (a group in which -CH2- in a methylene group is replaced with -S-), a sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), an alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced with -O-), an alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position in an alkanediyl group is replaced with -O-CO-), an alkanediylcarbonyl group (a an alkanediyl group in which -CH2- at any position is replaced with -CO-), an alkanediylcarbonyloxy group (an alkanediyl group in which -CH2-CH2- at any position is replaced with -CO-O-), an alkanediylsulfonyl group (an alkanediyl group in which -CH2- at any position is replaced with -SO2-), an alkanediylthio group (an alkanediyl group in which -CH2- at any position is replaced with -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group,Examples of such groups include an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, and a group that combines two or more of these groups. Examples also include groups in which one or more hydrogen atoms of these groups are replaced with a bonding site. Examples of such replaced groups include the same groups as those exemplified in this specification.

[0580] Furthermore, examples of groups in which --CH.sub.2-- contained in an alicyclic hydrocarbon group is replaced by --O--, --S--, --CO-- or --SO.sub.2-- include the same as those exemplified in this specification. Examples of the combined groups in which --CH2-- is replaced by --O--, --S--, --CO-- or --SO2-- include the following groups: The bonding site may be any position.

[0581] [ka]

[0582] L 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.

[0583] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a21The hydrocarbon group in the formula (I) can have a halogen atom as a substituent, and thus can have a substituent such as a haloalkyl group. Examples of the haloalkyl group include a fluorinated alkyl group, a chlorinated alkyl group, a brominated alkyl group, and an iodinated alkyl group, and examples thereof include a chloromethyl group, a bromomethyl group, an iodomethyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, and a perfluorobutyl group. The number of carbon atoms in the haloalkyl group is preferably 1 to 8, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3.

[0584] 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, still more preferably 1 to 8, still more preferably 1 to 6, still more preferably 1 to 4, and still more preferably 1 to 3.

[0585] L a21 L is a group in which -CH2- in the hydrocarbon group is replaced with -O- or -CO-, etc. a21can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, a thiol group, a sulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an acryloyloxy group, or a methacryloyloxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 12, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The number of carbon atoms in the alkoxycarbonyl group, the alkylcarbonyl group, or the alkylcarbonyloxy group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 to 3. The number of carbon atoms in the alkoxyalkyl group or the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 8, even more preferably 2 to 6, and even more preferably 2 to 4.

[0586] The above groups also include the same groups as those exemplified in this specification. L a21 The substituents which the hydrocarbon group in the formula (I) may have are preferably a halogen atom, a haloalkyl group having 1 to 8 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), more preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 10 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), still more preferably a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, a hydroxy group, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, still more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and still more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, or an ethoxyethoxy group.

[0587] Also, L a21In the case where the alkanediyl group is replaced by -O- or -CO-, for example, *-L a23 -X a21 -(L a23 represents an alkanediyl group having 1 to 8 carbon atoms; X a21 represents -O-, -O-CO-, -CO-O-, or -O-CO-O-, and * represents A a21 It is also preferred that the bond is

[0588] L a21 is preferably a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (however, -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (however, -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), or a group formed by combining a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent and a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (however, -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO- and -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-). and more preferably an optionally substituted chain hydrocarbon group having 1 to 10 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -CO- or -SO2-), or a group formed by combining an optionally substituted chain hydrocarbon group having 1 to 6 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO- and -CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2- or -CO-).

[0589] L a22Examples of the chain hydrocarbon group having 1 to 12 carbon atoms include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, and dodecane-1,12-diyl group. Examples of branched alkanediyl groups include ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, 1-methylpropane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, 1-dimethylpropane-1,3-diyl, pentane-2,4-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, and even more preferably 1 to 4.

[0590] Examples of the chain hydrocarbon group in which --CH.sub.2-- is replaced by --O-- or --CO-- include the same groups as those exemplified in this specification. L a22 may have one fluorine atom or two or more fluorine atoms.

[0591] na2 is preferably an integer of 1 to 4, and more preferably an integer of 1 to 3. L a21 In the case where R is a single bond or a chain hydrocarbon group, examples of the structural unit (a2) include the following structural units. a2 In the same manner as the following structural unit, a structural unit in which a methyl group corresponding to the following formula is replaced with a hydrogen atom or the like is also a suitable structural unit of the structural unit (a2).

[0592] [ka]

[0593] When a resist pattern is produced from the resist composition of the present invention, in the case where a high energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) is used as an exposure light source, the structural unit (a2) having a phenolic hydroxyl group is preferred, and the structural unit (a2-A) described below is more preferred. In addition, in the case where an ArF excimer laser (193 nm) or the like is used, the structural unit (a2) having an alcoholic hydroxyl group is preferred, and the structural unit (a2-C) described below is more preferred. The structural unit (a2) may contain one type alone or two or more types.

[0594] In the structural unit (a2), L a21 is a cyclic hydrocarbon group, and an example of a structural unit having a phenolic hydroxy group or a carboxy group is a structural unit represented by formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)").

[0595] [ka]

[0596] [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.

[0597] 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.

[0598] A a21represents 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.

[0599] 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 multiple parentheses may be the same or different.

[0600] 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 from 0 to 2. R a2 and A a21 The groups include the same groups as those exemplified in formula (a2).

[0601] R a27 Examples of the halogen atom include a fluorine atom, a chlorine atom, an iodine atom, and a bromine atom. R a27 Examples of the alkyl group having 1 to 6 carbon atoms, which may have a halogen atom, include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, and more preferably 1 to 3. The alkyl group is preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0602] R a27 Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 4, and more preferably 1 to 3. The alkoxy group is preferably a methoxy group or an ethoxy group, and more preferably a methoxy group.

[0603] R a27 Examples of the alkoxyalkyl group include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group.

[0604] R a27 Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 8, and more preferably 2 to 4. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, and more preferably a methoxyethoxy group or an ethoxyethoxy group.

[0605] R a27 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group.

[0606] Ra27 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 4, and more preferably 2 to 3. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group.

[0607] 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.

[0608] nA2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na21 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and further preferably 0 or 1.

[0609] mc is preferably 0 or 1. -X a2 -OH is a benzene ring, A a21 In particular, at least one of them is preferably bonded to the meta or para position, and more preferably to the meta position. In the case of a naphthalene ring, A a21 When the bonding position of A is the 1st position, it may be bonded to any of the 2nd to 8th positions. a21 When the bonding position of A is the 2-position, it may be bonded to any of the 1-position and the 3-8-positions. a21 When the bonding position of A is the 1st position, at least one of them is preferably bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. a21When the bonding position is the 2-position, it is preferably bonded to the 4- to 7-positions, and more preferably bonded to the 5- or 6-position.

[0610] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A-2010-204634 and JP-A-2012-12577. The structural unit (a2-A) includes structural units represented by formulae (a2-2-1) to (a2-2-32) and (a2-3-1) to (a2-3-24), and in these structural units, R in the structural unit (a2-A) a2 and the like, in which the methyl group corresponding to the following formula (I) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group.

[0611] [ka]

[0612] When the structural unit (a2-A) is contained in the resin (A), the content of the structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and even more preferably 20 mol% or more, based on the total structural units. Also, it is preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less, even more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 45 mol% or less, and even more preferably 40 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, even more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%.

[0613] The structural unit (a2-A) may be a compound from which the structural unit (a2-A) is derived (e.g., -CH2-C(-R a2 )- is the double bond CH2=C(-R a2) can be polymerized to incorporate the structural unit (a2-A') into the resin (A). Alternatively, for example, structural unit (a1-4) can be polymerized, followed by treatment with an acid such as p-toluenesulfonic acid, to incorporate the structural unit (a2-A) into the resin (A). Alternatively, structural unit (a2-A) can be polymerized, followed by treatment with an alkali such as tetramethylammonium hydroxide, to incorporate the structural unit (a2-A) into the resin (A).

[0614] 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)"), or a structural unit represented by formula (a2-D) (hereinafter may be referred to as "structural unit (a2-D)").

[0615] [ka]

[0616] [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).

[0617] L a25 is -O- or *-O-(CH2) k2 represents --CO--O--, and k2 represents an integer of 1 to 7. * represents a bonding site with --CO--. X a2 represents a single bond or -CO-.

[0618] 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.

[0619] nB22 represents an integer of 0 to 8. When nB22 is 2 or more, a plurality of R a27 may be the same or different from each other. nC22 represents an integer of 0 to 10. When nC22 is 2 or more, multiple R a27 may be the same or different. L a25 is preferably -O- or *-O-(CH2) f1 It is -CO-O- (wherein f1 represents an integer of 1 to 4), and more preferably -O-.

[0620] R a2 is preferably a methyl group. X a2 is preferably a single bond. R a25 is preferably a hydrogen atom.

[0621] 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.

[0622] nB2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. nB22 is preferably an integer of 0 to 3, more preferably 0, 1 or 2, and further preferably 0 or 1.

[0623] nC22 is preferably an integer of 0 to 6, more preferably an integer of 0 to 3, and further preferably 0 or 1. Examples of the structural unit (a2-B) and the structural unit (a2-C) include structural units derived from monomers described in JP-A-2010-204646, the following structural units, and R a2 In particular, structural units represented by any one of formulae (a2-B-1) to (a2-B-5) and formulae (a2-C-1) to (a2-C-9) are preferred.

[0624] [ka]

[0625] When the resin (A) contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on the total structural units of the resin (A). Also, the content is 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 is 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%.

[0626] [ka]

[0627] [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).

[0628] 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.

[0629] nD2 represents an integer of 1 to 5. When nD2 is 2 or more, the groups in the multiple parentheses may be the same or different. nD22 represents an integer of 0 to 4. When nD22 is 2 or more, a plurality of R a27 may be the same or different from each other.

[0630] 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.

[0631] R a21 and R a22 As the alkyl group, a trifluoromethyl group is preferable. L a24 Examples of the alkanediyl group include a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group.

[0632] L a24 is preferably a single bond or a methylene group. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group.

[0633] 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.

[0634] nD22 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, further preferably 0 or 1, and even more preferably 0. 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)").

[0635] [ka]

[0636] [In formula (a2-D1), R a2 , A a21 , R a27 , nD2 and nD22 each have the same meaning as in formula (a2-D). In formula (a2-D1), R a2 is preferably a hydrogen atom or a methyl group.

[0637] A a21 is preferably a single bond. Examples of the structural unit (a2-D) include the structural units shown below.

[0638] [ka]

[0639] In the structural units represented by formulae (a2-D-1) to (a2-D-8), R a2 In the structural units represented by formulae (a2-D-9) to (a2-D-16), the hydrogen atom corresponding to R a2 Specific examples of the structural unit (a2-D) include structural units in which the methyl group corresponding to the following formula is replaced with a hydrogen atom, etc. Among these, the structural units represented by formulae (a2-D-1) to (a2-D-8) are preferred, the structural units represented by formulae (a2-D-1) to (a2-D-4) are more preferred, and the structural unit represented by formula (a2-D-1) is even more preferred.

[0640] When the resin (A) contains the structural unit (a2-D), the content thereof is preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A). Also, it is preferably 80 mol% or less, more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 10 to 70 mol%, and even more preferably 10 to 65 mol%.

[0641] <Structural unit (a3)> The lactone ring of the structural unit (a3) ​​may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or may be a condensed ring of a monocyclic lactone ring and another ring. Preferred examples include a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)).

[0642] The structural unit (a3) ​​is preferably a structural unit represented by formula (a3-1), (a3-2), (a3-3) or (a3-4). One of these may be contained alone, or two or more of them may be contained.

[0643] [ka]

[0644] [In the formulas (a3-1), (a3-2), (a3-3) and (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 any of 1 to 7), and * represents a bonding site with a carbonyl group.

[0645] L a7 , -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -CO-OL a9 -CO-O- or *-OL a8 -O-CO-L a9 It represents -O-, and * represents the bonding site with the carbonyl group.

[0646] L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. 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.

[0647] X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 , Ra23 and R a25 each independently represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms.

[0648] p1 represents an integer of 0 to 5. q1 represents an integer of 0 to 3. r1 represents an integer of 0 to 3.

[0649] w1 represents an integer of 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, multiple R a21 , R a22 , R a23 and / or R a25 may be the same or different.] 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.

[0650] R a18 , R a19 , R a20 and R a24 Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R a18 , R a19 , R a20 and R a24 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group, and preferably includes an alkyl group having 1 to 4 carbon atoms, and more preferably includes a methyl group or an ethyl group.

[0651] R a18 , R a19 , R a20 and R a24Examples of the alkyl group having a halogen atom in the formula (I) include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group.

[0652] 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.

[0653] In formulas (a3-1) to (a3-3), L a4 ~L a6 are each independently preferably -O- or *-O-(CH2) k3 In the -CO-O- group, 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.

[0654] R a18 ~R a21 is preferably a methyl group. R a22 and R a23 are each independently preferably a carboxy group, a cyano group, or a methyl group.

[0655] p1, q1 and r1 each independently represent an integer of preferably 0 to 2, and more preferably 0 or 1. In formula (a3-4), R a24is 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.

[0656] R a25 is preferably a carboxy group, a cyano group or a methyl group. L a7 is preferably -O- or *-OL a8 It is -CO-O-, and more preferably -O-, *-O-CH2-CO-O- or *-O-C2H4-CO-O-.

[0657] 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)'.

[0658] [ka]

[0659] (In the formula, R a24 , L a7 has the same meaning as above.) Examples of the structural unit (a3) ​​include structural units derived from monomers described in JP 2010-204646 A, JP 2000-122294 A, and JP 2012-41274 A. Examples of the structural unit (a3) ​​include structural units represented by any one of formulas (a3-1-1), (a3-1-2), (a3-2-1), (a3-2-2), (a3-2x-1), (a3-2x-2), (a3-3-1), (a3-3-2), and (a3-4-1) to (a3-4-12), and in the structural unit, R in formulas (a3-1) to (a3-4) a18 , R a19 , R a20 and R a24 A structural unit in which a methyl group corresponding to the following formula is replaced with a hydrogen atom is preferred.

[0660] [ka]

[0661] When the resin (A) contains the structural unit (a3), the total content thereof is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A). Also, 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, 1 to 70 mol% is mentioned, preferably 3 to 70 mol%, more preferably 3 to 65 mol%, even more preferably 5 to 65 mol%, even more preferably 5 to 60 mol%, and even more preferably 10 to 60 mol%.

[0662] The content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3) or the structural unit (a3-4) is preferably 1 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A). It is also preferably 60 mol% or less, more preferably 55 mol% or less, even more preferably 50 mol% or less, even more preferably 40 mol% or less, even more preferably 30 mol% or less, even more preferably 25 mol% or less, and even more preferably 20 mol% or less. Specifically, it is preferably 1 to 60 mol%, more preferably 3 to 60 mol%, 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%.

[0663] <Structural unit (a4)> Examples of the structural unit (a4) include the following structural units.

[0664] [ka]

[0665] [In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents a saturated hydrocarbon group having 1 to 24 carbon atoms and containing a halogen atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.] R 42 Examples of the saturated hydrocarbon group represented by the formula (I) include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these groups.

[0666] Examples of the chain saturated hydrocarbon group include linear alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a dodecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, and an octadecyl group, and branched alkyl groups such as an isopropyl group and an isobutyl group.

[0667] Examples of the monocyclic or polycyclic alicyclic saturated hydrocarbon group include monocyclic alicyclic saturated hydrocarbon groups which are monocyclic cycloalkyl groups, such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic saturated hydrocarbon groups which are polycyclic cycloalkyl groups, such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* represents a bonding site):

[0668] [ka]

[0669] 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 saturated hydrocarbon groups, such as -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group.

[0670] Examples of the alkanediyl group include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and hexane-1,6-diyl groups, and branched alkanediyl groups such as propane-1,2-diyl, butane-1,3-diyl, 2-methylpropane-1,2-diyl, 1-methylbutane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. The terminal of the branched alkanediyl group may be a methyl group.

[0671] R 42 Examples of the halogen atom contained in the saturated hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 42Examples of the saturated hydrocarbon group in which -CH2- is replaced by -O- or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -CO-), an oxy group (a group in which -CH2- in a methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position in an alkyl group is replaced by -O-CO-), and an alkylcarbonyl group (a group in which -CH2- at any position in an alkyl group is replaced by -CO-). ), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced with -CO-O-), alkanediyloxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -O-), alkanediyloxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -O-CO-), alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced with -CO-), alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced with -CO-), cycloalkoxy group, cycloalkylalkoxy group, and the like, which are combinations of two or more of these groups. Examples of these substituted groups include the same as the groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0672] The structural unit (a4) is R 42 is preferably a saturated hydrocarbon group having a fluorine atom. 42However, examples of the structural unit (a4) which is a saturated hydrocarbon group having a fluorine atom include a structural unit represented by formula (a4-1) (hereinafter may be referred to as "structural unit (a4-1)"), a structural unit represented by formula (a4-2) (hereinafter may be referred to as "structural unit (a4-2)"), and a structural unit represented by formula (a4-3) (hereinafter may be referred to as "structural unit (a4-3)").

[0673] The structural unit represented by formula (a4-1) is a structural unit represented by the following formula:

[0674] [ka]

[0675] [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.

[0676] 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. 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.

[0677] L 42fExamples of the alkanediyl group having a fluorine atom in the formula (I) include linear alkanediyl groups having a fluorine atom, such as a methylene group having a fluorine atom, an ethylene group having a fluorine atom, a propane-1,3-diyl group having a fluorine atom, a butane-1,4-diyl group having a fluorine atom, a pentane-1,5-diyl group having a fluorine atom, a hexane-1,6-diyl group having a fluorine atom, a heptane-1,7-diyl group having a fluorine atom, and an octane-1,8-diyl group having a fluorine atom; Examples of branched alkanediyl groups having fluorine atoms include a -diyl group, a propane-1,1-diyl group having a fluorine atom, a propane-1,2-diyl group having a fluorine atom, a propane-2,2-diyl group having a fluorine atom, a pentane-2,4-diyl group having a fluorine atom, a 2-methylpropane-1,3-diyl group having a fluorine atom, a 2-methylpropane-1,2-diyl group having a fluorine atom, a pentane-1,4-diyl group having a fluorine atom, and a 2-methylbutane-1,4-diyl group having a fluorine atom. The terminal of the branched alkanediyl group may be a methyl group which may have a fluorine atom.

[0678] 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.

[0679] L 42fThe number of fluorine atoms contained in the alkanediyl group and cycloalkanediyl group having a fluorine atom in the above formula may be 1 or more, and is preferably 2 or more. L 42f The alkanediyl group and cycloalkanediyl group having a fluorine atom in the above formula (I) are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0680] 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.

[0681] 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.

[0682] 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.

[0683] L 42f is preferably a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and even more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0684] The structural unit (a4-1) may be any of the structural units shown below and R in the structural unit (a4-1) in the structural unit shown below. 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom.

[0685] [ka]

[0686] The structural unit represented by formula (a4-2) is a structural unit shown below.

[0687] [ka]

[0688] [In formula (a4-2), R 41 represents a hydrogen atom or a methyl group. L 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.

[0689] R 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, L 43f and R 43f At least one of L has a fluorine atom. 43f and R 43f The total number of carbon atoms in the molecule is limited to 21. L 43f and R 43f Examples of the saturated hydrocarbon group in include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these groups. 43f and R 43f Examples of saturated hydrocarbon groups in the formula are L 43f and R 43f As long as the upper limit of the total number of carbon atoms in 42 Examples of the saturated hydrocarbon group include the same groups as the saturated hydrocarbon groups exemplified above.

[0690] L 43f The saturated hydrocarbon group is preferably an alkanediyl group having 1 to 6 carbon atoms or a group represented by the formula (L43f-1).

[0691] [ka]

[0692] [In formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represents a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may contain a fluorine atom.

[0693] L 47f represents a single bond or a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may contain a fluorine atom. X 46f and X 47f each independently represents -O-, -CO-, -CO-O- or -O-CO-.

[0694] However, L 45f , L 46f , L 47f , X 46f and X 47f The total number of carbon atoms is 7 or less. * and ** are binding sites, ** is -O-CO-R 43fThis is the binding site for L in the group represented by formula (L43f-1) 45f , L 46f and L 47f Examples of the divalent saturated hydrocarbon group represented by include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and a divalent saturated hydrocarbon group formed by combining an alkanediyl group and a divalent alicyclic saturated hydrocarbon group, etc. Specific examples include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, etc.

[0695] It is preferred that s is 0. 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

[0696] [ka]

[0697] R 43f is preferably a saturated hydrocarbon group having a fluorine atom. In this case, examples of the structural unit represented by formula (a4-2) include structural units represented by formula (a4-2A) or (a4-2B).

[0698] [ka]

[0699] [In formula (a4-2A) and formula (a4-2B), R 41 and L 43f represents the same as in formula (a4-2). R 43fArepresents a saturated hydrocarbon group having 1 to 20 carbon atoms and containing a fluorine atom.

[0700] A 43f represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.

[0701] X 43 represents **-O-CO- or **-CO-O-, and ** represents A 43f It represents the binding site with R 43fB represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may contain a fluorine atom.

[0702] However, in formula (a4-2A), L 43f and R 43fA The total number of carbon atoms in formula (a4-2B) is 21 or less, and in formula (a4-2B), L 43f , A 43f , X 43 and R 43fB The total number of carbon atoms in A is 21 or less. 43f and R 43fB At least one of them has at least one fluorine atom. R 43fA The saturated hydrocarbon group of R is as long as the upper limit of the carbon number permits. 42 Examples of the saturated hydrocarbon groups include the saturated hydrocarbon groups exemplified by the above.

[0703] R 43fA is preferably an alkyl group having 1 to 13 carbon atoms and containing a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms and containing a fluorine atom, or a group combining these, *-(CF2) n43f -R 42′ (* represents the bonding site with the carbonyl group. n43f represents an integer of 1 to 6. R 42′ represents a hydrogen atom or a fluorine atom.) or a perfluorocycloalkyl group having 3 to 12 carbon atoms is more preferable.

[0704] A 43f and R43fB The saturated hydrocarbon group represented by R in formula (a4) is as large as possible within the upper limit of the number of carbon atoms. 42 Examples of the saturated hydrocarbon groups include the saturated hydrocarbon groups exemplified by the above. A 43f is preferably a divalent chain saturated hydrocarbon group which may have a fluorine atom, a divalent alicyclic saturated hydrocarbon group, or a combination thereof, more preferably a divalent chain saturated hydrocarbon group which has a fluorine atom, and further preferably a fluorinated alkanediyl group having 1 to 6 carbon atoms.

[0705] R 43fB The saturated hydrocarbon group which may have a fluorine atom is preferably a chain saturated hydrocarbon group which may have a fluorine atom, an alicyclic saturated hydrocarbon group or a group combining these, more preferably an alkyl group having 1 to 12 carbon atoms which may have a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms or a group combining these, and more preferably a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4 More preferred are fluorinated alkyl groups such as octafluorobutyl, 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.

[0706] In formula (a4-2B), *-A 43f -X 43 -R 43fBAn 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).

[0707] [ka]

[0708] The structural unit represented by formula (a4-2A) includes the structural units shown below and R in the structural unit represented by formula (a4-2A) in the structural units shown below. 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom.

[0709] [ka]

[0710] The structural unit represented by formula (a4-2B) includes the structural units shown below and R in the structural unit represented by formula (a4-2B) in the structural units shown below. 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom.

[0711] [ka]

[0712] The structural unit (a4) also includes a structural unit represented by formula (a4-3).

[0713] [ka]

[0714] [In formula (a4-3), R 41 represents a hydrogen atom or a methyl group. L 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.

[0715] R 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, L 44f and R 44f At least one of L has a fluorine atom. 44f and R 44f The total number of carbon atoms in the molecule is limited to 21. L 44f and R 44f Examples of the saturated hydrocarbon group in include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these groups. 44f and R 44f Examples of saturated hydrocarbon groups in the formula are L 44f and R 44f As long as the upper limit of the total number of carbon atoms in 42 Examples of the saturated hydrocarbon group include the same groups as the exemplified saturated hydrocarbon groups.

[0716] L 44f is preferably an alkanediyl group having 1 to 14 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 -or-(CH2) j4 -CO-O-(CH2) j5 It is more preferably a group represented by the formula: - (j1 to j5 each independently represent an integer of 1 to 6). It is also more preferably an alkanediyl group having 1 to 4 carbon atoms (one -CH2- contained in the alkanediyl group may be replaced by -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced by -CO-O- or -O-CO-).

[0717] R 44fis preferably a saturated hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, an alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms and having a fluorine atom, or a group combining these, further preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom.

[0718] Examples of the structural unit represented by formula (a4-3) include the following structural units and structural units represented by the following formulas: 41 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom.

[0719] [ka]

[0720] When the resin (A) 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 (A).

[0721] <Structural unit (a5)> The non-leaving hydrocarbon group contained in the structural unit (a5) may be a group containing a linear, branched or cyclic hydrocarbon group. Among these, the structural unit (a5) is preferably a group containing an alicyclic hydrocarbon group.

[0722] An example of the structural unit (a5) is a structural unit represented by the formula (a5-1).

[0723] [ka]

[0724] [In formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52represents 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.

[0725] 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-.] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group, a norbornyl group, and the like.

[0726] Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, and a 2-ethylhexyl group.

[0727] An example of the alicyclic hydrocarbon group having a substituent is a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an adamantyl group, a norbornyl group, or a cyclohexyl group.

[0728] L 55 Examples of the divalent saturated hydrocarbon group in include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, and a divalent chain saturated hydrocarbon group is preferred. Examples of the divalent chain saturated hydrocarbon group include alkanediyl groups such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, and a pentanediyl group.

[0729] 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.

[0730] L 55 Examples of the divalent saturated hydrocarbon group represented by formula (L1-1) to formula (L1-4) include groups represented by formula (L1-2) to (L1-4). In the following formulae, * and ** each represent a bonding site, and * represents a bonding site with an oxygen atom.

[0731] [ka]

[0732] [In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents L x1 ) which represents the binding site with

[0733] 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.

[0734] 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.

[0735] 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.

[0736] 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.

[0737] 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.

[0738] 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.

[0739] L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms.

[0740] 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.

[0741] L x6is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms.

[0742] L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, and more preferably a single bond or a methylene group.

[0743] W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, and more preferably a cyclohexanediyl group or an adamantanediyl group. Examples of the group represented by formula (L1-1) include the divalent groups shown below.

[0744] [ka]

[0745] Examples of the group represented by formula (L1-2) include the divalent groups shown below.

[0746] [ka]

[0747] Examples of the group represented by formula (L1-3) include the divalent groups shown below.

[0748] [ka]

[0749] Examples of the group represented by formula (L1-4) include the divalent groups shown below.

[0750] [ka]

[0751] L 55 is preferably a single bond or a group represented by formula (L1-1). The structural unit (a5-1) may be any of the structural units shown below and R in the structural unit (a5-1) in the structural unit shown below. 51 In the structural unit, a methyl group corresponding to the above formula is replaced with a hydrogen atom.

[0752] [ka]

[0753] When the resin (A) contains the structural unit (a5), the content thereof is preferably from 1 to 30 mol %, more preferably from 2 to 20 mol %, and even more preferably from 3 to 15 mol %, based on all structural units in the resin (A).

[0754] <Structural unit (a6)> The structural unit (a6) is a structural unit having a -SO2- group, and preferably has the -SO2- group in a side chain.

[0755] The structural unit having a -SO2- group may have a linear structure having a -SO2- group, may have a branched structure having a -SO2- group, or may have a cyclic structure (monocyclic and polycyclic structure) having a -SO2- group. A structural unit having a cyclic structure having a -SO2- group is preferred, and a structural unit having a cyclic structure (sultone ring) containing -SO2-O- is more preferred.

[0756] The sultone ring may be represented by the following formula (T 1 -1), formula (T 1 -2), formula (T 1 -3) and the formula (T 1The bonding site can be any position. The sultone ring may be monocyclic, but is preferably polycyclic. A polycyclic sultone ring refers to a bridged ring containing -SO2-O- as an atomic group constituting the ring, and is represented by the formula (T 1 -1) and the formula (T 1 The sultone ring is represented by the formula (T 1 As in the ring represented by formula (2), the atomic group constituting the ring may further contain a heteroatom in addition to -SO2-O-. Examples of the heteroatom include an oxygen atom, a sulfur atom, or a nitrogen atom, and an oxygen atom is preferred.

[0757] [ka]

[0758] The sultone ring may have a substituent. Examples of the substituent include an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, and an alkylcarbonyl group having 2 to 4 carbon atoms.

[0759] Examples of halogen atoms include fluorine, chlorine, bromine and iodine atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, and a decyl group, and preferably an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group.

[0760] Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group, and preferably a trifluoromethyl group.

[0761] Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a 2-hydroxyethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group.

[0762] Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.

[0763] Aralkyl groups include benzyl, phenethyl, phenylpropyl, naphthylmethyl and naphthylethyl groups. Examples of the alkoxycarbonyl group include groups in which an alkoxy group, such as a methoxycarbonyl group or an ethoxycarbonyl group, is bonded to a carbonyl group, and preferably, an alkoxycarbonyl group having 6 or less carbon atoms is used, and more preferably, a methoxycarbonyl group is used.

[0764] Alkylcarbonyl groups include acetyl, propionyl and butyryl groups. From the viewpoint of ease of production of the monomer from which the structural unit (a6) is derived, a sultone ring having no substituent is preferred.

[0765] The sultone ring is preferably a ring represented by the following formula (T1').

[0766] [ka]

[0767] [In formula (T1′), X 11 represents an oxygen atom, a sulfur atom, or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms.

[0768] ma represents an integer of 0 to 9. When ma is 2 or more, multiple R 41 may be the same or different. The binding site is at any position.] X 11 is preferably an oxygen atom or a methylene group, and more preferably a methylene group.

[0769] R 41 Examples of the substituent include the same ones as the substituents on the sultone ring, and an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxyl group is preferred. ma is preferably 0 or 1, and more preferably 0.

[0770] Examples of the ring represented by formula (T1') include the following rings. The binding site may be any position. Among them, the binding site is preferably the 1st or 3rd position.

[0771] [ka]

[0772] The structural unit having a -SO2- group preferably further has a group derived from a polymerizable group, such as a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, or a methacryloylthio group.

[0773] Among these, the monomer from which the structural unit (a6) is derived is preferably a monomer having an ethylenically unsaturated bond, and more preferably a (meth)acrylic monomer. The structural unit (a6) is preferably a structural unit represented by the formula (a6-0).

[0774] [ka]

[0775] [In formula (a6-0), R x represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom.

[0776] A xx is an oxygen atom, -N(R c )- or a sulfur atom. A x represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH- contained in the saturated hydrocarbon group is -O-, -CO- or -N(R d )- may also be replaced.

[0777] X 11 represents an oxygen atom, a sulfur atom, or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms.

[0778] ma represents an integer of 0 to 9. When ma is 2 or more, multiple R 41 may be the same or different. R c and R d each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.] R x Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

[0779] R x Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group. An alkyl group having 1 to 4 carbon atoms is preferred, and a methyl group or an ethyl group is more preferred.

[0780] R x Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group.

[0781] R x is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group. A x Examples of the divalent saturated hydrocarbon group include a linear alkanediyl group, a branched alkanediyl group, and a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and may be a combination of two or more of these groups.

[0782] Specific examples thereof 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 heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, a heptadecane-1,17-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group. branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group; monocyclic divalent alicyclic saturated hydrocarbon groups such as cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group; and polycyclic divalent alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group.

[0783] A x The bonding position of to the sultone ring may be any position, but is preferably the 1-position. Examples of the structural unit (a6-0) include the following structural units.

[0784] [ka]

[0785] Of these, structural units represented by formulae (a6-1), (a6-2), (a6-6), (a6-7), (a6-8) and (a6-12) are preferred, and structural units represented by formulae (a6-1), (a6-2), (a6-7) and (a6-8) are more preferred.

[0786] When the resin (A) contains the structural unit (a6), the content thereof is preferably from 1 to 50 mol %, more preferably from 2 to 40 mol %, and even more preferably from 3 to 30 mol %, based on all structural units in the resin (A).

[0787] <Structural unit (a7)> The resin may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter, may be referred to as "structural unit (a7)"). Specific examples of the structural unit (a7) include structural units described in JP 2016-79235 A, and are preferably structural units having a sulfonate group or carboxylate group and an organic cation in a side chain, or a structural unit having a sulfonio group and an organic anion in a side chain.

[0788] The structural unit having a sulfonate group or carboxylate group and an organic cation in the side chain is preferably a structural unit represented by formula (a7-A).

[0789] [ka]

[0790] [In formula (a7-A), R a7 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.

[0791] X a71 is a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR a71 -**, *-NR a71 -CO-O-**, *-O-CO-NR a71 -** or *-Ax-Ph-Ay-**.

[0792] R a71 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one type of bond selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate bond.

[0793] * and ** represent binding sites, * represents R a7 represents the bonding site with the carbon atom to which it is bonded. L a71 and L a72 each independently represents a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-.

[0794] X a72 represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, and *** represents L a71 It represents the binding site with na7 represents an integer of 0 to 2. When na7 is 2, the groups in the parentheses may be the same or different.

[0795] RA - represents a sulfonate anion or a carboxyl anion. Z.A. + represents an organic cation. R a7 and R a71 Examples of the alkyl group having 1 to 6 carbon atoms in the formula include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group.

[0796] R a7 Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a7Examples of the alkyl group having 1 to 6 carbon atoms and having a halogen atom in the formula (I) include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a dichloromethyl group, a triiodomethyl group, a diiodomethyl group, a tribromomethyl group, and a dibromomethyl group.

[0797] R a7 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, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0798] X a71 is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10).

[0799] [ka]

[0800] [In formula (X10), Ax is R a7 represents a bond type bonded to the carbon atom to which is bonded, and represents one type of bond selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate bond, and an amide bond.

[0801] Ay is L a71 represents a bond type that bonds with, and represents one type of bond selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate bond, and an amide bond.

[0802] Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents an integer of 0 to 4, and when mx is an integer of 2 or more, multiple Rx's may be the same or different. When either Ax or Ay is a single bond, the other is preferably one selected from the group consisting of an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond.

[0803] When either Ax or Ay is an amide bond, -CO-NR a71 A bond represented by - is preferred. The bonding position of Ay in the phenylene group is preferably the meta or para position relative to the bonding position of Ax, and more preferably the para position.

[0804] Among these, Rx is preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group or an ethyl group. mx is preferably 0, 1 or 2.

[0805] X a71 Examples of the group include a single bond and the group represented by the following formula (X 10 -1)~Formula(X 10 -10) is a group represented by * -R a7 represents the bonding site with the carbon atom to which L is bonded. a71 It represents the binding site with X 20 is -O- or -NR a71 - represents.

[0806] [ka]

[0807] Expression(X 10 -1)~Formula(X 10 Specific examples of the group represented by -10) include the following groups.

[0808] [ka]

[0809] Among them, X a71 is a single bond and the formula (X 10 -1′), equation (X 10 -3′)~Formula(X 10 -9′), which is preferably a single bond or a group represented by the formula (X 10 -1′), equation (X 10 -4′), formula (X 10 -5′), formula (X 10 -6') and formula (X 10 -9') is more preferably a single bond, a group represented by the formula (X 10 -1'), a group represented by the formula (X 10 -5′), a group represented by the formula (X 10 -6') or formula (X 10 -9') is more preferable.

[0810] L a71 The hydrocarbon group is a group formed by removing one hydrogen atom from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, to form X. a71 and X a72 Also, L a72 The hydrocarbon group is a group formed by removing one hydrogen atom from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining two or more of these groups, to form X. a72 and R.A. - Examples of such groups include groups that bond to the

[0811] L a71 and L a72Examples of the chain hydrocarbon group include a group in which one hydrogen atom has been removed from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentanedecyl group, and a heptadecyl group. Examples of the alkenyl group include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, and a nonenyl group.

[0812] The chain hydrocarbon group preferably has 1 to 20 carbon atoms, more preferably 1 to 18 carbon atoms, and even more preferably 1 to 10 carbon atoms. L a71 and L a72 Examples of the alicyclic hydrocarbon group include a group in which one hydrogen atom has been removed from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cycloheptyl group, a cyclohexyl group, a cyclopentyl group, and a cyclooctyl group.

[0813] L a71 and L a72Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a bridged structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are bonded by a spiro bond. Examples of the cycloalkyl group having a bridged structure include a norbornyl group and an adamantyl group. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group and a steroid group (steroid skeleton). Examples of the cycloalkyl group in which two rings are bonded by a spiro bond include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group is bonded by a spiro bond to a cycloalkyl group having 5 to 8 carbon atoms. A double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group include the following formula:

[0814] [ka]

[0815] When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 3 to 12, and even more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the alicyclic hydrocarbon group preferably has 6 to 18 carbon atoms, and more preferably 7 to 12.

[0816] L a71 and L a72 The aromatic hydrocarbon group may be a group in which one hydrogen atom has been removed from an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a fluorenyl group. The number of carbon atoms in the aromatic hydrocarbon group is preferably 5 to 14, more preferably 6 to 14, and further preferably 6 to 10.

[0817] L a71 and L a72When --CH2-- in the hydrocarbon group is replaced with --O--, --CO--, --S-- or --SO2--, the number of carbon atoms before the replacement is regarded as the number of carbon atoms in the hydrocarbon group.

[0818] L a71 and L a72 Among the hydrocarbon groups in the above, groups in which -CH2- in a chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a hydroxy group (a group in which -CH2- in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced by -S-), a carbonyl group (a group in which -CH2- in a methylene group is replaced by -O-), and 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 thio group (a group in which -CH2- in a methylene group is replaced with -S-), a sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), an alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), an alkoxycarbonyl group (an alkyl group in which -CH2- at any position is replaced with -O-), any position in the alkyl group is replaced with -O-CO-), an alkylcarbonyl group (an alkyl group in which -CH2- at any position is replaced with -CO-), an alkylcarbonyloxy group (an alkyl group in which -CH2-CH2- at any position is replaced with -CO-O-), an alkanediyloxy group (an alkanediyl group in which -CH2- at any position is replaced with -O-), Examples of the substituted groups include an alkanediyloxycarbonyl group (a group in which -CH-CH- at any position contained in an alkanediyl group is replaced with -O-CO-), an alkanediylcarbonyl group (a group in which -CH- at any position contained in an alkanediyl group is replaced with -CO-), and an alkanediylcarbonyloxy group (a group in which -CH-CH- at any position contained in an alkanediyl group is replaced with -CO-O-). Examples of 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.

[0819] L a71 and L a72 Among the above hydrocarbon groups, examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2- include groups containing a cyclic ether, cyclic ketone, cyclic ester (lactone), cyclic thioether, cyclic acetal, and cyclic sulfonate ester (sultone) structure. Specific examples include alicyclic hydrocarbon groups represented by the following formula. The bonding position of the alicyclic hydrocarbon groups listed in the following formula may be any position.

[0820] [ka]

[0821] L a71 and L a72 Among these hydrocarbon groups, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and examples of the group in which -CH2- is replaced by -O- or -S- include groups derived from a furan ring or a thiophene ring, respectively.

[0822] L a71 and L a72 Examples of the group in which two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group are combined include a group in which the chain hydrocarbon group and the alicyclic hydrocarbon group are combined, a group in which the chain hydrocarbon group and the aromatic hydrocarbon group are combined, a group in which the alicyclic hydrocarbon group and the aromatic hydrocarbon group are combined, and a group in which the chain hydrocarbon group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group are combined. The group in which the alicyclic hydrocarbon group and the aromatic hydrocarbon group are combined may be a condensed ring.

[0823] L a71 and L a72 The substituents which the hydrocarbon group may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0824] L a71 and L a72 When L is a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. a71 and L a72 The -CH2- of the chain hydrocarbon group contained in the hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2-, thereby forming L a71 and L a72 The hydrocarbon group may substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, or a sulfonyl group.

[0825] na7 is preferably 0 or 1. ZA in formula (a7-A) + Examples of the cation include the same as the cation in the salt represented by formula (B1) etc.

[0826] In formula (a7-A), L a71 and L a72 When the hydrocarbon group is a saturated hydrocarbon group, in the formula (a7-B) described later, b7 The divalent linking group may include the same groups as those exemplified above.

[0827] Examples of the structural unit represented by formula (a7-A) include a structural unit represented by formula (a7-A1).

[0828] [ka]

[0829] [In formula (a7-A1), R a7 , X a71 , L a71 , X a72 , na7, R.A. - and Z.A. + has the same meaning as above.

[0830] z7 represents an integer of 0 to 6. Q a7 , Q b7 , R z71 and R z72 each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms; when z7 is 2 or more, z71 and R z72 may be the same or different.] Q a7 , Q b7 , R z71 and R z72 As the perfluoroalkyl group having 1 to 6 carbon atoms or the alkyl group having 1 to 6 carbon atoms in R a7 Examples of the groups include the same groups as those exemplified in the above.

[0831] Examples of the structural unit represented by formula (a7-A) include the following structural units, R a7 Examples of the structural units include those in which the group corresponding to the methyl group in the above formula (I) is replaced with a hydrogen atom, a halogen atom (e.g., a fluorine atom) or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group, etc.), and the structural units described in WO 2012 / 050015. + represents an organic cation.

[0832] [ka]

[0833] [ka]

[0834] The structural unit having a sulfonio group and an organic anion on the side chain is preferably a structural unit represented by formula (a7-B).

[0835] [ka]

[0836] [In formula (a7-B), R a7 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom.

[0837] A b7 represents a single bond or a divalent linking group. R b71 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. R b72 and R b73 each independently represents a hydrocarbon group having 1 to 18 carbon atoms which may have a substituent; R b72 and R b73 may be bonded to each other to form a ring together with the sulfur atom to which they are attached.

[0838] A - represents an organic anion. R a7 Examples of the halogen atom and the alkyl group which may have a halogen atom in the formula (a7-A) include the same halogen atom and the alkyl group which may have a halogen atom as in the formula (a7-A).

[0839] R b71 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by the formula (I) include a phenylene group and a naphthylene group. R b72 and R b73 Examples of the hydrocarbon group represented by the formula (I) include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups.

[0840] Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups formed by combining these groups include those similar to those described above. A b7Examples of the divalent linking group represented by the formula (I) include divalent saturated hydrocarbon groups having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S- or -CO-.

[0841] Examples of the divalent saturated hydrocarbon group include divalent chain saturated hydrocarbon groups such as linear or branched alkanediyl groups, and monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and combinations of these are also possible.

[0842] Specifically, straight-chain alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, and dodecane-1,12-diyl group; divalent monocyclic alicyclic saturated hydrocarbon groups such as monocyclic cycloalkanediyl groups, such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group; and divalent polycyclic alicyclic saturated hydrocarbon groups, such as polycyclic cycloalkanediyl groups, such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group.

[0843] Examples of saturated hydrocarbon groups in which -CH2- has been replaced with -O-, -S-, or -CO- include the following divalent groups. However, the number of carbon atoms before the -CH2- in the saturated hydrocarbon group is replaced with -O-, -S-, or -CO- is 17 or less. In the following formulas, * and ** represent binding sites, * represents R b71 It represents the binding site with

[0844] [ka]

[0845] [where, X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X 4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0846] X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. The structural unit containing a cation in formula (a7-B) includes the structural units represented by the following formula: a7 Examples of such structural units include those in which a group corresponding to the methyl group in the above formula (I) is replaced with a hydrogen atom, a halogen atom (e.g., a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., a trifluoromethyl group, etc.).

[0847] [ka]

[0848] A - Examples of the organic anion represented by the formula (I) include a sulfonate anion, a sulfonylimide anion, a sulfonylmethide anion, and a carboxylate anion. - The organic anion represented by the formula (I) is preferably a sulfonate anion, and the sulfonate anion is more preferably the same as the anion exemplified for the acid generator (B). Examples of the sulfonylimide anion, sulfonylmethide anion, and carboxylate anion include the same anions exemplified for the acid generator (B).

[0849] Examples of the structural unit represented by formula (a7-B) include structural units represented below.

[0850] [ka]

[0851] When the resin (A) contains the structural unit (a7), the structural unit (a7) may be contained alone or in combination of two or more kinds. The total content of the structural unit (a7) is preferably 1 to 30 mol%, more preferably 1 to 25 mol%, even more preferably 2 to 20 mol%, still more preferably 3 to 15 mol%, and even more preferably 3 to 10 mol%, based on the total structural units of the resin (A).

[0852] Resin (A) may contain structural units other than the above-mentioned structural units, and examples of such structural units include structural units well known in the art. The resin (A) is preferably a resin composed of the structural unit (a1) and the structural unit (s), that is, a copolymer of the monomer (a1) and the monomer (s).

[0853] The structural unit (a1) is preferably at least one selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), the structural unit (a1-2) (preferably a structural unit having a cyclohexyl group or a cyclopentyl group), the structural unit represented by formula (a1-4), the structural unit represented by formula (a1-5), and the structural unit represented by formula (a1-6), more preferably at least two, and even more preferably at least two selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2).

[0854] The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably the structural unit (a2-C) or the structural unit (a2-A). The structural unit (a3) ​​is preferably at least one selected from the group consisting of the structural unit represented by the formula (a3-1), the structural unit represented by the formula (a3-2), and the structural unit represented by the formula (a3-4).

[0855] Each structural unit constituting the resin (A) may be used alone or in combination of two or more, and can be produced by a known polymerization method (e.g., radical polymerization method) using a monomer that leads to these structural units. The content of each structural unit contained in the resin (A) can be adjusted by the amount of the monomer used for polymerization.

[0856] The weight average molecular weight of the resin (A) is preferably 2,000 or more (more preferably 2,500 or more, even more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, even more preferably 15,000 or less), but may contain an oligomer having a weight average molecular weight smaller than these. In this specification, the weight average molecular weight is a value determined by gel permeation chromatography under the conditions described in the Examples.

[0857] <Resins other than resin (A)> The resist composition of the present invention may contain a resin other than the resin (A) in combination. Examples of resins other than resin (A) include resins containing the structural unit (a4) or the structural unit (a5) (hereinafter, sometimes referred to as resin (X)).

[0858] As the resin (X), among others, a resin containing a structural unit (a4) is preferable, a resin containing a structural unit having a fluorine atom is more preferable, and a resin containing at least one structural unit represented by formula (a4-1), formula (a4-2), and formula (a4-3) is further preferable.

[0859] Examples of structural units that the resin (X) may further have include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. When the resin (X) contains the structural unit (a4), the content of the structural unit (a4) in the resin (X) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more, based on the total of all structural units in the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. When the resin (X) contains the structural unit (a5), the content of the structural unit (a5) in the total of all structural units in the resin (X) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more. Also, 100 mol% or less may be mentioned, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, 20 to 100 mol% may be mentioned, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. Also, when the resin (X) contains the structural unit (a4) and the structural unit (a5), the total content of the structural unit (a4) and the structural unit (a5) may be 40 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more, and even more preferably 80 mol% or more, based on the total of all the structural units of the resin (X). Also, 100 mol% or less may be mentioned. Specifically, 40 to 100 mol% may be mentioned, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and even more preferably 80 to 100 mol%.

[0860] In particular, the resin (X) is preferably a resin consisting only of the structural unit (a4) and / or the structural unit (a5). In this case, the ratio of the structural unit (a4):structural unit (a5) is 0:100 to 100:0, preferably 10:90 to 90:10, and more preferably 30:70 to 70:30 or 40:60 to 60:40.

[0861] Each structural unit constituting the resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (e.g., radical polymerization method) using a monomer that derives these structural units. The content of each structural unit in the resin (X) can be adjusted by the amount of the monomer used for polymerization.

[0862] The weight average molecular weight of resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less), but may contain oligomers having a lower weight average molecular weight than this. The method for measuring the weight average molecular weight of resin (X) is the same as that for resin (A).

[0863] When the resist composition of the present invention contains resin (X), the content thereof is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, even more preferably 1 to 40 parts by mass, still more preferably 1 to 30 parts by mass, and particularly preferably 1 to 8 parts by mass, relative to 100 parts by mass of resin (A).

[0864] When the resist composition contains resin (A), the content of resin (A) is preferably 60% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 99% by mass or less, even more preferably 80% by mass or more and 99% by mass or less, and even more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. When a resin other than resin (A) is contained, the total content of resin (A) and resin other than resin (A) is preferably 60% by mass or more and 99% by mass or less, more preferably 70% by mass or more and 99% by mass or less, even more preferably 80% by mass or more and 99% by mass or less, and even more preferably 90% by mass or more and 99% by mass or less, based on the solid content of the resist composition. The solid content of the resist composition and the resin content therewith can be measured by a known analytical means such as liquid chromatography or gas chromatography.

[0865] <Solvent (E)> The content of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less, preferably 92% by mass or more and 99% by mass or less, and more preferably 94% by mass or more and 99% by mass or less. The content of the solvent (E) can be measured by a known analytical method such as liquid chromatography or gas chromatography.

[0866] Examples of the solvent (E) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; esters such as ethyl lactate, butyl acetate, amyl acetate, and ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone, and cyclohexanone; cyclic esters such as γ-butyrolactone; etc. One type of solvent (E) may be used alone, or two or more types may be used.

[0867] <Quencher (C)> Examples of the quencher (C) include salts that generate an acid having a weaker acidity than the acid generated from the basic nitrogen-containing organic compound and the acid generator (salt (I) or compound (B)). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15 mass%, more preferably about 0.01 to 10 mass%, even more preferably about 0.1 to 8 mass%, and even more preferably about 0.1 to 7 mass%, based on the solid content of the resist composition.

[0868] The basic nitrogen-containing organic compound includes amines and ammonium salts. The amines include aliphatic amines and aromatic amines. The aliphatic amines include primary amines, secondary amines, and tertiary amines.

[0869] Amines include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, Amines, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine amine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane Examples of the amines include 1,2-di(4-pyridyl)ethane, 1,2-di(2-pyridyl)ethene, 1,2-di(4-pyridyl)ethene, 1,3-di(4-pyridyl)propane, 1,2-di(4-pyridyloxy)ethane, di(2-pyridyl)ketone, 4,4'-dipyridyl sulfide, 4,4'-dipyridyl disulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, and bipyridine. Preferred are aromatic amines such as diisopropylaniline, and more preferred are 2,6-diisopropylaniline.

[0870] Examples of the ammonium salt include tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylammonium salicylate, choline, and the like.

[0871] The acidity of a salt that generates an acid with a lower acidity than the acid generated from the acid generator is indicated by the acid dissociation constant (pKa). A salt that generates an acid with a lower acidity than the acid generated from the acid generator is a salt having an acid dissociation constant of the acid generated from the salt usually of -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5.

[0872] Examples of the salt that generates an acid with a lower acidity than the acid generated from the acid generator include salts represented by the following formula, salts represented by formula (D) described in JP-A-2015-147926 (hereinafter sometimes referred to as "weak acid inner salt (D)"), and salts described in JP-A-2012-229206, JP-A-2012-6908, JP-A-2012-72109, JP-A-2011-39502, and JP-A-2011-191745. The salt that generates an acid with a lower acidity than the acid generated from the acid generator is preferably a salt that generates a carboxylic acid with a lower acidity than the acid generated from the acid generator (a salt having a carboxylic acid anion), more preferably a weak acid inner salt (D), and still more preferably a diphenyliodonium salt containing a phenyl group substituted with a carboxylic acid anion among the weak acid inner salts (D).

[0873]

Chemical formula

[0874] The weak acid inner salt (D) is preferably a diphenyliodonium salt having an iodonium cation to which two phenyl groups are bonded and a carboxylate anion substituted for at least one of the two phenyl groups bonded to the iodonium cation, and specifically includes salts represented by the following formula:

[0875] [ka]

[0876] [In formula (D), R D1 and R D2 each independently represents a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 7 carbon atoms, an acyloxy group having 2 to 7 carbon atoms, an alkoxycarbonyl group having 2 to 7 carbon atoms, a nitro group, or a halogen atom.

[0877] m′ and n′ each independently represent an integer of 0 to 4, and when m′ is 2 or more, a plurality of R D1 may be the same or different, and when n' is 2 or more, a plurality of R D2 may be the same or different.] R D1 and R D2 Examples of the hydrocarbon group include chain hydrocarbon groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups.

[0878] Examples of the chain hydrocarbon group include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, and a nonyl group.

[0879] The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and may be either saturated or unsaturated. Examples of the alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclononyl, and cyclododecyl, norbornyl, and adamantyl groups.

[0880] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a 4-propylphenyl group, a 4-isopropylphenyl group, a 4-butylphenyl group, a 4-t-butylphenyl group, a 4-hexylphenyl group, a 4-cyclohexylphenyl group, an anthryl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.

[0881] Groups formed by combining these groups include alkyl-cycloalkyl groups, cycloalkyl-alkyl groups, and aralkyl groups (e.g., phenylmethyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenyl-1-propyl group, 1-phenyl-2-propyl group, 2-phenyl-2-propyl group, 3-phenyl-1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, and 6-phenyl-1-hexyl group).

[0882] Examples of the alkoxy group include a methoxy group and an ethoxy group. Examples of the acyl group include an acetyl group, a propanoyl group, a benzoyl group, and a cyclohexanecarbonyl group.

[0883] Examples of the acyloxy group include the above-mentioned acyl group to which an oxy group (-O-) is bonded. Examples of the alkoxycarbonyl group include the above alkoxy groups bonded to a carbonyl group (-CO-).

[0884] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. R D1 and R D2are each independently preferably an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 2 to 4 carbon atoms, a nitro group or a halogen atom.

[0885] m′ and n′ are each preferably an integer of 0 to 2, more preferably 0. When m′ is 2 or more, multiple R D1 may be the same or different, and when n' is 2 or more, a plurality of R D2 may be the same or different.

[0886] More specifically, the following salts are included:

[0887] [ka]

[0888] <Other Ingredients> The resist composition of the present invention may contain components other than the above-mentioned components (hereinafter, sometimes referred to as "other components (F)") as necessary. There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, etc., can be used.

[0889] Preparation of Resist Composition The resist composition of the present invention can be prepared by mixing the salt (I), and, if necessary, the resin (A), the compound (B), a resin other than the resin (A), the solvent (E), the quencher (C), and other components (F). The order of mixing is arbitrary and is not particularly limited. The temperature during mixing can be selected from 10 to 40°C depending on the type of resin, the solubility of the resin in the solvent (E), and the like. The mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is not particularly limited, and stirring and mixing can be used.

[0890] After mixing the components, it is preferable to filter the mixture using a filter having a pore size of about 0.003 to 0.2 μm. <Method for Producing Resist Pattern> The method for producing a resist pattern of the present invention comprises the steps of: (1) applying the resist composition of the present invention onto a substr...

Claims

1. An acid generator comprising a salt represented by formula (I): 【Chemistry 1】 [In formula (I), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1, and when X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0. R １Ａ and R １Ｂ Each independently represents -X １ -R １０ , -X １ -L １０ -X ２ -R １０ Represents. X １ and X ２ are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (wherein * represents a benzene ring or L １０ ) represents the binding site with L １０ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -SO ２ It may be replaced by --or --CO--. R １０ represents a base labile group. R ４ represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, and the —CH ２ - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced with -. R ７ , R ８ and R ９ each independently represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, ２ - is -O-, -S-, -CO-, -SO- or -SO ２ When X is a sulfur atom, R ７ and R ８ Or R ８ and R ９ is bonded to S ＋ The R forming the ring may form a ring containing ７ and R ８ Or R ８ and R ９ , S ＋ The —CH ２ - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced with -. m1A represents an integer of 0 to 5, and when m1A is 2 or more, a plurality of R １Ａ may be the same or different from each other. m1B represents an integer of 0 to 4, and when m1B is 2 or more, a plurality of R １Ｂ may be the same or different, provided that either m1A or m1B is an integer of at least 1. m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R ４ may be the same or different, and satisfy 0≦m1A+m4≦5. m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R ７ may be the same or different, and satisfy 0≦m1B+m7≦4. m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R ８ may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R ９ may be the same or different from each other. AI － represents an organic anion.

2. m1A is an integer of 1 to 3, R １Ａ But -O-CO-R １０ Or -O-L １０ -C-O-R １０ 2. The acid generator according to claim 1,

3. R １０ 2. The acid generator according to claim 1, wherein the base labile group is a group represented by formula (1b): 【Chemistry 2】 [In formula (1b), R ｂａ１ and R ｂａ２ each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom. R ｂａ３ represents a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom. * indicates a binding site.

4. AI － The acid generator according to claim 1, wherein is an anion represented by formula (IA): 【Chemistry 3】 [In formula (IA), L ｂ１ represents a single bond or a (nb1+1)-valent hydrocarbon group which may have a substituent, and —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. L ｂ２ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced 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- 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.

5. Y ｂ１ represents a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and the -CH ２ - is -O-, -S-, -CO- or -SO ２ The acid generator according to claim 4, which may be replaced by -.

6. AI － is an anion represented by formula (I-A1). 【Chemistry 4】 [In formula (I-A1), Q ｂ１ , Q ｂ２ , Q ｂ３ and Q. ｂ４ each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. z1 represents an integer of 0 to 6. When z1 is 2 or more, the groups in the parentheses may be the same or different. X １ represents -O-CO-, -CO-O-, -O-CO-O- or -O-. L ｂ２ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. L ｂ３ represents a single bond or a (nb2+1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH ２ - is -O-, -S-, -CO- 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- or -SO ２ It may be replaced with -. nb2 represents an integer of 1 to 3. When nb2 is 2 or more, the groups in the parentheses may be the same or different.]

7. AI － is an anion represented by formula (I-A2). 【Chemistry 5】 [In formula (I-A2), R ｂ１ represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and the —CH ２ - may be replaced by -O- or -CO-. L ｂ２ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced 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- or -SO ２ It may be replaced with -. nb4 represents an integer of 1 to 5. When nb4 is 2 or more, the groups in the multiple parentheses may be the same or different. nb3 represents an integer of 0 to 4. When nb3 is 2 or more, a plurality of R ｂ１ may be the same or different from each other. However, 1≦nb4+nb3≦5 is satisfied.

8. A resist composition comprising the acid generator according to any one of claims 1 to 7.

9. Further comprising a resin including a structural unit having an acid labile group, The resist composition according to claim 8, wherein the structural unit having an acid labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). 【Chemistry 6】 [In formula (a1-0), formula (a1-1) and formula (a1-2), L ａ０１ , L ａ１ and L ａ２ are each independently -O- or *-O-(CH ２ ) ｋ１ represents --CO--O--, k1 represents an integer of 1 to 7, and * represents the bonding site with --CO--. R ａ０１ , R ａ４ and R ａ５ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ０２ , R ａ０３ and R ａ０４ each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, and the alkyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may contain a halogen atom. R ａ６ and R ａ７ each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom. m1′ represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. 【Chemistry 7】 [In formula (a1-4), R ａ１ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ１７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ１１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the —CH ２ - is -O-, -CO- or -NR ａ１８ May be replaced with -. R ａ１８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ１ represents a single bond or 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 a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the hydrocarbon group and the -CH ２ - may be replaced by -O- or -S-. na1 represents an integer of 1 to 5, and when na1 is 2 or more, the groups in the parentheses may be the same or different. na11 represents an integer of 0 to 4, and when na11 is 2 or more, a plurality of R ａ１７ may be the same or different from each other. mc represents an integer of 0 to 2. 【Chemistry 8】 [In formula (a1-5), R ａ８ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Z ａ１ is a single bond or *-(CH ２ ) ｈ３ -CO-L ５４ -, h3 represents an integer of 1 to 4, * represents L ５１ represents the binding site with L ５１ , L ５２ , L ５３ and L ５４ each independently represents --O-- or --S--. s1 represents an integer of 1 to 3. s1' represents an integer of 0 to 3. 【Chemistry 9】 [In formula (a1-6), R ａ６１ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ６２ , R ａ６３ and R ａ６４ each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R ａ６２ and R ａ６３ are bonded to each other to form, together with the carbon atoms to which they are attached, a ring having 3 to 20 carbon atoms. X ａ６１ is a single bond, -CO-O-* or -CO-NR ５ - represents *, * represents a bonding site with Ar, R ５ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X ａ６２ is a single bond, *-O-L ａ６１ - or *-CO-OL ａ６２ -, * represents a bonding site with Ar, L ａ６１ and L ａ６２ each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.

10. Further comprising a resin including a structural unit having an acid labile group, 9. The resist composition according to claim 8, wherein the resin containing a structural unit having an acid labile group further contains a structural unit represented by formula (a2-A). 【Chemistry 10】 [In formula (a2-A), R ａ２ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the —CH ２ - is -O-, -CO- or -NR ａ２８ 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.

11. 9. The resist composition according to claim 8, further comprising a salt capable of generating an acid having a weaker acidity than the acid generated from said acid generator.

12. (1) A step of applying the resist composition according to claim 8 onto a substrate; (2) A step of drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising the steps of:

13. A salt represented by formula (I): 【Chemistry 11】 [In formula (I), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1, and when X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0. R １Ａ and R １Ｂ Each independently represents -X １ -R １０ , -X １ -L １０ -X ２ -R １０ Represents. X １ and X ２ are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (wherein * represents a benzene ring or L １０ ) represents the binding site with L １０ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -SO ２ It may be replaced by --or --CO--. R １０ represents a base labile group. R ４ represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, and the —CH ２ - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced with -. R ７ , R ８ and R ９ each independently represents a halogen atom or a hydrocarbon group having 1 to 36 carbon atoms, the hydrocarbon group optionally having a substituent, ２ - is -O-, -S-, -CO-, -SO- or -SO ２ When X is a sulfur atom, R ７ and R ８ Or R ８ and R ９ is bonded to S ＋ The R forming the ring may form a ring containing ７ and R ８ Or R ８ and R ９ , S ＋ The —CH ２ - is -O-, -S-, -CO-, -SO- or -SO ２ It may be replaced with -. m1A represents an integer of 0 to 5, and when m1A is 2 or more, a plurality of R １Ａ may be the same or different from each other. m1B represents an integer of 0 to 4, and when m1B is 2 or more, a plurality of R １Ｂ may be the same or different, provided that either m1A or m1B is an integer of at least 1. m4 represents an integer of 0 to 5, and when m4 is 2 or more, a plurality of R ４ may be the same or different, and satisfy 0≦m1A+m4≦5. m7 represents an integer of 0 to 4, and when m7 is 2 or more, a plurality of R ７ may be the same or different, and satisfy 0≦m1B+m7≦4. m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R ８ may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R ９ may be the same or different from each other. AI － represents an organic anion.

14. m1A is an integer of 1 to 3, R １Ａ But -O-CO-R １０ Or -O-L １０ -C-O-R １０ The salt according to claim 13, wherein

15. R １０ 15. The salt according to claim 13 or 14, wherein the base labile group is a group represented by formula (1b): 【Chemistry 12】 [In formula (1b), R ｂａ１ and R ｂａ２ each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom. R ｂａ３ represents a fluorine atom or an alkyl group having 1 to 6 carbon atoms and a fluorine atom. * indicates a binding site.

16. AI － The salt according to claim 13 or 14, wherein is an anion represented by formula (IA). 【Chemistry 13】 [In formula (IA), L ｂ１ represents a single bond or a (nb1+1)-valent hydrocarbon group which may have a substituent, and —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. L ｂ２ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced 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- 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.

17. Y ｂ１ represents a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and the -CH ２ - is -O-, -S-, -CO- or -SO ２ The salt according to claim 16, which may be replaced by -.

18. AI － The salt according to claim 13 or 14, wherein is an anion represented by formula (I-A1). 【Chemistry 14】 [In formula (I-A1), Q ｂ１ , Q ｂ２ , Q ｂ３ and Q. ｂ４ each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. z1 represents an integer of 0 to 6. When z1 is 2 or more, the groups in the parentheses may be the same or different. X １ represents -O-CO-, -CO-O-, -O-CO-O- or -O-. L ｂ２ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced with -. L ｂ３ represents a single bond or a (nb2+1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH ２ - is -O-, -S-, -CO- 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- or -SO ２ It may be replaced with -. nb2 represents an integer of 1 to 3. When nb2 is 2 or more, the groups in the parentheses may be the same or different.]

19. AI － The salt according to claim 13 or 14, wherein is an anion represented by formula (I-A2). 【Chemistry 15】 [In formula (I-A2), R ｂ１ represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and the —CH ２ - may be replaced by -O- or -CO-. L ｂ２ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH ２ - is -O-, -S-, -CO- or -SO ２ It may be replaced 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- or -SO ２ It may be replaced with -. nb4 represents an integer of 1 to 5. When nb4 is 2 or more, the groups in the multiple parentheses may be the same or different. nb3 represents an integer of 0 to 4. When nb3 is 2 or more, a plurality of R ｂ１ may be the same or different from each other. However, 1≦nb4+nb3≦5 is satisfied.

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