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

Abstract

The present invention aims to provide a salt, an acid generator, and a resist composition that can produce a resist pattern with good line edge roughness. The present invention provides an acid generator and a resist composition containing a salt represented by formula (I). TIFF2026042751000171.tif33148[where, Q 1 , Q 2 , R 1 and R 2 are hydrogen atoms, fluorine atoms, etc.; z is an integer of 0 to 6; X 1Z is -O-, -CO-, etc.; mm1 is 0 or 1; L 1 is a single bond or a substituted / unsubstituted hydrocarbon group; L 2 is a substituted / unsubstituted hydrocarbon group; R 4 represents a halogen atom, a cyano group, etc.; R 5 -X 1 -L 12 -R 10 etc., X 1 -CO-O-, etc., L 12 is a single bond or a substituted / unsubstituted hydrocarbon group, R 10 represents a group containing a cyclic ether structure; m4 and m5 represent integers of 1 to 4; mm2 represents an integer of 1 to 3; Z + represents an organic cation.]

Description

[Technical Field]

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

[0002] Patent Document 1 describes resist compositions containing a salt represented by the following formula as an acid generator. TIFF2026042751000001.tif2781 [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2024-068158 Summary of the Invention [Problem to be solved by the invention]

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

[0005] The present invention includes the following inventions. [1] An acid generator containing a salt represented by formula (I). TIFF2026042751000002.tif35147 [In formula (I), Q 1 , Q 2 , R 1 and R 2 each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents an integer of 0 to 6, and when z is 2 or more, a plurality of R 1 and R 2may be the same or different from each other. X 1Z are -O-, -CO-, -S-, -SO-, -SO2-, -NR 6 - or a group combining these. mm1 represents 0 or 1. L 1 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -SO-, -SO2-, -NR 6 It may be replaced by - or -CO-. L 2 represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -SO-, -SO2-, -NR 6 However, L contained in the hydrocarbon group may be replaced by - or -CO-. 1 The -CH2- directly attached to the benzene ring is not replaced with -O-. R 6 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R 4 represents a halogen atom, a cyano group, an amino group, a nitro group, or an alkyl group having 1 to 12 carbon atoms, a hydrogen atom contained in the alkyl group may be substituted with a halogen atom, a cyano group, an amino group, or a nitro group, and -CH2- contained in the alkyl group may be -O-, -CO-, -S-, -SO-, -SO2-, or -NR 6 - may be replaced. R 5 -X 1 -L 12 -R 10 , -X 2 -L 11 -X 1 -L 12 -R 10 Represents. X 1 and X 2 are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * represents L 2 or L 11 represents the binding site with . L 11 represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -SO2-, -SO-, and -NR 6 It may be replaced by - or -CO-. L 12 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -SO2-, -SO-, -NR 6 It may be replaced by - or -CO-. R 10 represents a group containing a cyclic ether structure. m4 represents an integer of 1 to 4, and when m4 is 2 or more, a plurality of R 4 may be the same or different from each other. m5 represents an integer of 1 to 4, and when m5 is 2 or greater, the groups in the parentheses may be the same or different. However, 2≦m4+m5≦5. mm2 represents an integer of 1 to 3, and when mm2 is 2 or greater, the groups in the parentheses may be the same or different. Z + represents an organic cation. [2] At least one L 2 -R 5 However, L in the benzene ring 1 The acid generator according to [1], wherein the compound is bonded at the o-position or p-position relative to the bonding position of [3]L 1 is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining these (provided that the alkanediyl group and the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the alkanediyl group and the cyclic hydrocarbon group is not -O-, -S-, -SO2-, -SO-, -NR 6 The acid generator according to [1] or [2], wherein - may be replaced by - or -CO-. [4]R 10The acid generator according to any one of [1] to [3], wherein the group containing a cyclic ether structure is a group represented by formula (IA), a group represented by formula (IB), or a group represented by formula (IC). TIFF2026042751000003.tif31114 [In formula (IA) and formula (IB), R A represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R A are either the same or different. s1 represents 1 or 2. t1 represents 0 or 1, provided that the sum of s1 and t1 is 1 or 2. L 12A represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -CO-, -SO-, -NR 7 It may be replaced by - or -SO2-. L 13A represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -CO-, -SO-, and -NR 7 It may be replaced by - or -SO2-. R 7 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * denotes a binding site.] TIFF2026042751000004.tif3348[In formula (IC), R A represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R A are either the same or different. s12 represents an integer of 0 to 2. t12 represents an integer of 0 to 2, provided that the sum of s12 and t12 is an integer of 0 to 2. L 13Arepresents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -CO-, -SO-, and -NR 7 It may be replaced by - or -SO2-. R 7 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * denotes a binding site.] [5]L 2 is a linear alkanediyl group having 1 to 6 carbon atoms. [6] A resist composition containing the acid generator according to any one of [1] to [5]. [7] Further, the composition contains a resin containing a structural unit having an acid labile group, The resist composition according to [6], 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). TIFF2026042751000005.tif44144 [In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 are each independently -O- or -O-(CH2) k1 represents —CO—O—, k1 represents an integer of 1 to 7, and * represents the bonding site with —CO—. R a01 , R a4 and R a5 each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 , R a03 and R a04each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may contain a halogen atom. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may contain a halogen atom. m1' represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. TIFF2026042751000006.tif31118[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 -CH2- contained in the alkanediyl group is -O-, -CO- or -NR a18 - may be replaced with R a18 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a1 represents a single bond or a carbonyl group. R a34 and R a35each 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 a34 represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a35 and R a36 are bonded to each other to form a divalent heterocyclic group having 3 to 20 carbon atoms together with the -CO- to which they are bonded, and -CH2- contained in the hydrocarbon group and the divalent heterocyclic group may be replaced with -O- or -S-. na1 represents an integer of 1 to 5, and when na1 is 2 or more, the groups in the parentheses may be the same or different from each other. na11 represents an integer of 0 to 4, and when na11 is 2 or more, a plurality of R a17 may be the same or different from each other. mc represents an integer between 0 and 2. TIFF2026042751000007.tif4558[In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, a hydrogen atom, or a halogen atom. Z a1 is a single bond or -(CH2) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents -O- or -S-. s1 represents an integer of 1 to 3. s1' represents an integer of 0 to 3. TIFF2026042751000008.tif3581[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 a63and 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, and R a64 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. X a61 is a single bond, -CO-O-* or -CO-NR a65 -*, * represents the binding site with Ar, R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 is a single bond, *-OL a61 -or*-CO-OL a62 -, * represents the bonding site with Ar, L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.] [8] The resist composition according to [6] or [7], further comprising a resin containing a structural unit represented by formula (a2-A): TIFF2026042751000009.tif30128[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 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 with R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a2 represents a single bond or a carbonyl group. nA2 represents an integer of 1 to 5, and when nA2 is 2 or greater, the groups in the parentheses may be the same or different from each other. na21 represents an integer of 0 to 4, and when na21 is 2 or more, a plurality of R a27 may be the same or different from each other. mc represents an integer between 0 and 2. [9] The resist composition according to any one of [6] to [8], further comprising a salt that generates an acid that is weaker in acidity than the acid generated from the acid generator.

[10] (1) A step of applying the resist composition according to any one of [6] to [9] onto a substrate; (2) 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:

[11] A salt represented by the above formula (I).

[12] At least one L 2 -R 5 However, L in the benzene ring 1 The salt according to

[11] , wherein the compound is bonded at the o- or p-position relative to the bonding position of

[13] L 1 is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining these (provided that the alkanediyl group and the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the alkanediyl group and the cyclic hydrocarbon group is not -O-, -S-, -SO2-, -SO-, -NR6 - or -CO-.) The salt according to

[11] or

[12] ,

[14] R 10 The salt according to any one of

[11] to

[13] , wherein the group containing a cyclic ether structure is the group represented by the above formula (IA), the group represented by the formula (IB), or the group represented by the formula (IC).

[15] L 2 is a linear alkanediyl group having 1 to 6 carbon atoms. [Effects of the Invention]

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

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

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

[0009] [Anion (I)] In formula (I), Q 1 , Q 2 , R 1 and R 2Examples of the perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, etc. The number of carbon atoms in the perfluoroalkyl group is preferably 1 to 4, and more preferably 1 to 3. Q 1 , Q 2 , R 1 and R 2 Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 4, and more preferably 1 to 3. Q 1 and Q 2 Preferably, at least one of them contains a fluorine atom or a perfluoroalkyl group, more preferably at least one of them is a fluorine atom or a perfluoroalkyl group, further preferably each is independently a trifluoromethyl group or a fluorine atom, and even more preferably both are fluorine atoms. R 1 and R 2 are each independently preferably a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group, more preferably a hydrogen atom or a fluorine atom, and even more preferably a hydrogen atom. z is preferably an integer of 0 to 4, more preferably an integer of 0 to 3, even more preferably an integer of 0 to 2, and even more preferably 0 or 1. X 1Z -O-, -CO-, -NR 6 - or a combination thereof is preferred, such as *-CO-O-, *-O-CO-, *-O-, *-O-CO-O-, *-NR 6 -, *-CO-NR 6 -, *-NR 6 -CO-, *-NR 6 -CO-O- or *-O-CO-NR6 - is more preferred, *-CO-O-, *-O-CO- or *-O-CO-O- is even more preferred, *-CO-O- or *-O-CO- is even more preferred (* is C(R 1 )(R 2 ) or C(Q 1 )(Q 2 ) represents the binding site with ). R 6 Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 4, and more preferably 1 to 3. R 6 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, even more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0010] L 1 and L 2 Examples of the hydrocarbon group in include linear or branched chain hydrocarbon groups such as alkanediyl groups, monocyclic or polycyclic (including spiro rings, fused rings, or bridged rings) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may also be groups combining two or more of these groups (for example, hydrocarbon groups formed from an alicyclic hydrocarbon group and a chain hydrocarbon group). Chain hydrocarbon groups and alicyclic hydrocarbon groups are also called aliphatic hydrocarbon groups, and alicyclic hydrocarbon groups and aromatic hydrocarbon groups are also called cyclic hydrocarbon groups. 1 The hydrocarbon group is a (mm2+1)-valent hydrocarbon group, and can be a divalent to tetravalent hydrocarbon group depending on mm2. The hydrocarbon group preferably has 1 to 24 carbon atoms, more preferably 1 to 20 carbon atoms, and even more preferably 1 to 18 carbon atoms. Examples of the chain hydrocarbon group include an alkanediyl group, and 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. The terminal of the branched alkanediyl group may be an alkyl group such as a methyl group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The chain hydrocarbon group may have 1 to 24 carbon atoms, preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 10, still more preferably 1 to 9, even more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. Examples of the monocyclic or polycyclic divalent alicyclic hydrocarbon group include the following groups: The binding site can be at any position. TIFF2026042751000010.tif42165Specifically, the alicyclic hydrocarbon group may be a monocyclic divalent alicyclic hydrocarbon group such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, or a cyclooctane-1,5-diyl group, Examples of the divalent alicyclic hydrocarbon group include a cycloalkyl group such as norbornane-1,4-diyl, norbornane-2,5-diyl, adamantane-1,5-diyl, adamantane-2,6-diyl, spirocyclohexane-1,2'-cyclopentane, and spiroadamantane-2,3'-cyclopentane; and a polycyclic cycloalkanediyl group such as a spiro ring having a cycloalkyl group bonded to a norbornyl group or an adamantyl group via a spiro bond. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The alicyclic hydrocarbon group may have 3 to 24 carbon atoms, preferably 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. Examples of the aromatic hydrocarbon group include arylene groups such as a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, and a phenanthrylene group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The aromatic hydrocarbon group may have 6 to 24 carbon atoms, preferably 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. Examples of groups combining two or more types include a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group, a group combining an aromatic hydrocarbon group with a chain hydrocarbon group, a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group and a chain hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may each be combined. In addition, when any group is X 1Z Alternatively, it may be bonded to a benzene ring. Examples of groups combining an alicyclic hydrocarbon group and a chain hydrocarbon group include -divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-alkanediyl group-, and -alkanediyl group-divalent alicyclic hydrocarbon group-. Examples of groups combining an aromatic hydrocarbon group and a chain hydrocarbon group include -divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-alkanediyl group-, and -alkanediyl group-divalent aromatic hydrocarbon group-. Examples of groups combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group include -aromatic hydrocarbon group-alicyclic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-. L 1 and L 2 -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms is -O-, -S-, -SO-, -SO2-, -NR 6 It may be replaced by - or -CO-. L 1 and L 2 The -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms is -O-, -S-, -SO-, -SO2-, -NR 6 When it is replaced with - or -CO-, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the hydrocarbon group. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO-, -SO2-, or -NR 6 Examples of the group substituted with - or -CO- include a hydroxy group (a group in which -CH2- in a methyl group is replaced with -O-), a carboxy group (a group in which -CH2-CH2- in an ethyl group is replaced with -O-CO-), a thiol group (a group in which -CH2- in a methyl group is replaced with -S-), an amino group (a group in which -CH2- in a methyl group is replaced with -NR 6 -), oxy group (a group in which -CH2- in a methylene group is replaced with -O-), carbonyl group (a group in which -CH2- in a methylene group is replaced with -CO-), thio group (a group in which -CH2- in a methylene group is replaced with -S-), sulfonyl group (a group in which -CH2- in a methylene group is replaced with -SO2-), peptide group (a group in which -CH2-CH2- in an ethylene group is replaced with -CO-NR 6-), alkoxy group (a group in which -CH2- at any position in an alkyl group is replaced with -O-), alkylthio group (a group in which -CH2- at any position in an alkyl group is replaced with -S-), alkylsulfonyl group (a group in which -CH2- at any position in an alkyl group is replaced with -SO2-), alkylamino group (a group in which -CH2- at any position in an alkyl group is replaced with -NR 6 -), alkyl peptide group (wherein -CH2-CH2- at any position in the alkyl group is replaced by -CO-NR 7-), alkoxycarbonyl group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -O-CO-), alkylcarbonyl group (a group in which -CH2- at any position in the alkyl group is replaced with -CO-), alkylcarbonyloxy group (a group in which -CH2-CH2- at any position in the alkyl group is replaced with -CO-O-), alkoxycarbonyloxy group (a group in which -CH2-CH 2-CH2- is replaced by -O-CO-O-), alkoxyalkoxy group (a group in which two -CH2- at any position in an alkyl group are replaced by -O-), alkoxyalkyl group (a group in which -CH2- at any position in an alkyl group is replaced by -O-), hydroxyalkyl group (a group in which -CH2- in a methyl group at any position in an alkyl group is replaced by -O-), alkanediyloxy group (a group in which -CH2- at any position in an alkanediyl group is replaced by -O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -O-), an alkanediylcarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -O-CO-), an alkanediylcarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-), an alkanediylcarbonyloxy group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyl group in which -CH2- at any position is replaced with -CO-O-), an alkanediyloxycarbonyl group (an alkanediyloxycarbon ... alkanediylsulfonyl group (a group in which -CH- at any position in an alkanediyl group is replaced with -SO-), alkanediylthio group (a group in which -CH- at any position in an alkanediyl group is replaced with -S-), alkanediylamino group (a group in which -CH- at any position in an alkanediyl group is replaced with -NR 6 -), alkanediyl peptide group (wherein any -CH2-CH2- at any position in the alkanediyl group is replaced by -CO-NR 6-substituted), cycloalkoxy groups, cycloalkylalkoxy groups, aromatic hydrocarbon group-carbonyloxy groups, aromatic hydrocarbon group-carbonyl groups, aromatic hydrocarbon group-oxy groups, and groups combining two or more of these groups. Examples of the alkoxy group include alkoxy groups having 1 to 27 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, etc. The number of carbon atoms in the alkoxy group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylthio group include alkylthio groups having 1 to 27 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, an octylthio group, a 2-ethylhexylthio group, a nonylthio group, a decylthio group, an undecylthio group, etc. The number of carbon atoms in the alkylthio group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 27 carbon atoms, such as a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, a butylsulfonyl group, a pentylsulfonyl group, a hexylsulfonyl group, an octylsulfonyl group, a 2-ethylhexylsulfonyl group, a nonylsulfonyl group, a decylsulfonyl group, an undecylsulfonyl group, etc. The number of carbon atoms in the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkylamino group include alkylamino groups having 1 to 27 carbon atoms, such as methylamino group, ethylamino group, dimethylamino group, propylamino group, butylamino group, pentylamino group, hexylamino group, etc. The number of carbon atoms in the alkylamino group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkyl peptide group include alkyl peptide groups having 1 to 27 carbon atoms, such as a methyl peptide group, an ethyl peptide group, a propyl peptide group, etc. The number of carbon atoms in the alkyl peptide group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 27 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 28 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 27 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 26 carbon atoms, such as a butoxycarbonyloxy group. Examples of the alkoxyalkoxy group include alkoxyalkoxy groups having 2 to 26 carbon atoms, such as a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, and an ethoxyethoxy group. The alkoxycarbonyl group has preferably 2 to 11 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkylcarbonyl group has preferably 2 to 12 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkylcarbonyloxy group has preferably 2 to 11 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkoxycarbonyloxy group has preferably 2 to 10 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. The alkoxyalkoxy group has preferably 2 to 10 carbon atoms, more preferably 2 to 6, even more preferably 2 to 4, and still more preferably 2 or 3. Examples of the alkoxyalkyl group include alkoxyalkyl groups having 2 to 27 carbon atoms, such as a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, an ethoxypropyl group, an ethoxybutyl group, a propoxymethyl group, etc. The number of carbon atoms in the alkoxyalkyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the hydroxyalkyl group include hydroxyalkyl groups having 1 to 27 carbon atoms, such as a hydroxymethyl group, a dihydroxymethyl group, a hydroxyethyl group, a dihydroxyethyl group, a hydroxypropyl group, etc. The number of carbon atoms in the hydroxyalkyl group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediyloxy group include alkanediyloxy groups having 1 to 27 carbon atoms, such as a methyleneoxy group, an ethyleneoxy group, a propanediyloxy group, a butanediyloxy group, a pentanediyloxy group, etc. The number of carbon atoms in the alkanediyloxy group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediyloxycarbonyl group include alkanediyloxycarbonyl groups having 2 to 27 carbon atoms, such as a methyleneoxycarbonyl group, an ethyleneoxycarbonyl group, a propanediyloxycarbonyl group, and a butanediyloxycarbonyl group. Examples of the alkanediylcarbonyl group include alkanediylcarbonyl groups having 2 to 18 carbon atoms, such as a methylenecarbonyl group, an ethylenecarbonyl group, a propanediylcarbonyl group, a butanediylcarbonyl group, and a pentanediylcarbonyl group. Examples of the alkanediylcarbonyloxy group include alkanediylcarbonyloxy groups having 2 to 27 carbon atoms, such as a methylenecarbonyloxy group, an ethylenecarbonyloxy group, a propanediylcarbonyloxy group, and a butanediylcarbonyloxy group. Examples of the alkanediyloxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 26 carbon atoms, such as a butoxycarbonyloxy group. The number of carbon atoms in the alkanediyloxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediyloxycarbonyloxy group is preferably 2 to 10, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediylsulfonyl group include alkanediylsulfonyl groups having 1 to 27 carbon atoms, such as a methylenesulfonyl group, an ethylenesulfonyl group, a propylenesulfonyl group, etc. The number of carbon atoms in the alkanediylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediylthio group include alkanediylthio groups having 1 to 27 carbon atoms, such as a methylenethio group, an ethylenethio group, a propylenethio group, etc. The number of carbon atoms in the alkanediylthio group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediylamino group include alkanediylamino groups having 1 to 27 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, etc. The number of carbon atoms in the alkanediylamino group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alkanediyl peptide group include alkanediyl peptide groups having 1 to 27 carbon atoms, such as a methylene peptide group, an ethylene peptide group, a propylene peptide group, etc. The number of carbon atoms in the alkanediyl peptide group is preferably 1 to 11, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of cycloalkoxy groups include cycloalkoxy groups having 3 to 27 carbon atoms, such as a cyclohexyloxy group. Examples of cycloalkylalkoxy groups include cycloalkylalkoxy groups having 4 to 27 carbon atoms, such as a cyclohexylmethoxy group. Examples of aromatic hydrocarbon group-carbonyloxy groups include aromatic hydrocarbon group-carbonyloxy groups having 7 to 27 carbon atoms, such as a benzoyloxy group. Examples of aromatic hydrocarbon group-carbonyl groups include aromatic hydrocarbon group-carbonyl groups having 7 to 28 carbon atoms, such as a benzoyl group. Examples of aromatic hydrocarbon group-oxy groups include aromatic hydrocarbon group-oxy groups having 6 to 27 carbon atoms, such as a phenyloxy group.

[0011] In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be replaced with -O-, -S-, -CO-, -NR 6Examples of groups substituted with -, -SO- or -SO2- include the following groups: -O- or -CO- in the groups shown below are -S- and -NR2-, respectively. 6 The binding site may be at any position. TIFF2026042751000011.tif89165Note, L 2 The -CH2- contained in the hydrocarbon group is -O-, -S-, -CO-, -NR 6 When -, -SO- or -SO2- is substituted, -CH2- bonded to the benzene ring is preferably not substituted with -O-, and -O-, -S-, -NR2-, -CH2- bonded to the benzene ring is preferably not substituted with -O-, and 6 It is more preferable that it is not replaced by -, -SO- or -SO2-, and -O-, -S-, -CO-, -NR 6 It is more preferred that it is not replaced by -, -SO- or -SO2-. If mm2 is 2 or 3, L 1 is a trivalent or tetravalent hydrocarbon group, in which any one or two hydrogen atoms contained in the divalent hydrocarbon group described above are replaced by a phenylene group in the parentheses of mm2.

[0012] L 1 and L 2 Examples of the substituent that may be possessed by L include a halogen atom, a cyano group, and a nitro group. 1 and L 2 The -CH2- contained in the chain hydrocarbon group such as the alkyl group contained in 6 - or -SO2-, which essentially results in L 1 and L 2 may have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkylamino group, an amino group, a thiol group, an alkylthio group, an alkylsulfonyl group, or an alkylpeptide group. 1 and L 2However, in the case of a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group such as an alkyl group, the chain hydrocarbon group such as an alkyl group can essentially be used as a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The substituent is preferably an alkyl group having 1 to 6 carbon atoms (wherein —CH— contained in the alkyl group may be replaced with —O— or —CO—) or a halogen atom, more preferably a hydroxy group, an alkoxy group having 1 to 4 carbon atoms or a halogen atom, and even more preferably a hydroxy group, an alkoxy group having 1 to 3 carbon atoms, a fluorine atom or an iodine atom.

[0013] L 1 represents 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 is not limited to -O-, -S-, -SO2-, -SO-, -NR 6 - or -CO-), 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 by -O-, -S-, -SO2-, -SO-, -NR 6 - or -CO-) or a group in which a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent is combined with a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group and the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2-, -SO-, -NR 6 - or -CO-), and examples thereof include a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining these (provided that the alkanediyl group and the cyclic hydrocarbon group may have a substituent, and -CH2- contained in the alkanediyl group and the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO-, -SO2-, -NR 6- or -CO-), and is preferably a single bond, an alkanediyl group having 1 to 6 carbon atoms (provided that -CH2- contained in the alkanediyl group may be replaced with -O- or -CO-), a group formed by combining an alkanediyl group having 1 to 6 carbon atoms with an alicyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the alkanediyl group may be replaced with -O- or -CO-, and -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO-, -SO2- or -CO-), or a group formed by combining an alkanediyl group having 1 to 6 carbon atoms with an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent (provided that - contained in the alkanediyl group and a single bond, an alkanediyl group having 1 to 4 carbon atoms, a group formed by combining an alkanediyl group having 1 to 4 carbon atoms with an alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- in the alkanediyl group may be replaced with -O- or -CO-, and wherein -CH2- in the alicyclic hydrocarbon group may be replaced with -O- or -CO-), or a group formed by combining an alkanediyl group having 1 to 4 carbon atoms with a phenylene group which may have a substituent (wherein -CH2- in the alkanediyl group may be replaced with -O- or -CO-). L 2 represents a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group is not limited to -O-, -S-, -SO2-, -SO-, -NR 6 - or -CO-), 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 by -O-, -S-, -SO2-, -SO-, -NR 6 - or -CO-) or a group in which a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent is combined with a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group and the cyclic hydrocarbon group may be replaced with -O-, -S-, -SO2-, -SO-, -NR 6- or -CO-), preferably an alkanediyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), more preferably a linear alkanediyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), even more preferably a methylene group or a carbonyl group, and even more preferably a methylene group. However, L 2 The -CH2- contained in the hydrocarbon group is -O-, -S-, -SO-, -SO2-, -NR 6 When replaced by - or -CO-, it is preferable that -CH2- bonded to the benzene ring is not replaced by -O-, and is preferably -O-, -S-, -SO-, -SO2- or -NR 6 It is more preferable that - is not replaced with -, and -O-, -S-, -SO-, -SO2-, -NR 6 It is more preferred that it is not replaced by - or -CO-.

[0014] R 4 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 4 Examples of the alkyl group include linear or branched alkyl groups, such as 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. R 4The alkyl group may be a haloalkyl group having a halogen atom, and examples thereof include a fluorinated alkyl group having 1 to 12 carbon atoms, a chlorinated alkyl group having 1 to 12 carbon atoms, a brominated alkyl group having 1 to 12 carbon atoms, and an iodinated alkyl group having 1 to 12 carbon atoms. Examples of the haloalkyl group include a perfluoroalkyl group having 1 to 12 carbon atoms (e.g., a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, and a nonafluorobutyl group), a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoropropyl group, a 4,4,4-trifluorobutyl group, a 3,3,4,4,4-pentafluorobutyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The 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. R 4 The alkyl group may have a cyano group, an amino group, or a nitro group. The alkyl group preferably has 1 to 9 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and even more preferably 1 to 3 carbon atoms.

[0015] R 4 The -CH2- in the alkyl group is -O-, -S-, -CO-, -SO-, -NR 6 When the alkyl group is substituted with - or -SO2-, the number of carbon atoms before the substitution is the total number of carbon atoms in the alkyl group. The -CH2- in the alkyl group can be -O-, -S-, -CO-, -SO-, or -NR 6As described above, examples of the group substituted for - or -SO- include a hydroxy group, a thiol group, a carboxy group, an amino group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkoxyalkyl group, a hydroxyalkyl group, an alkylamino group, an alkylpeptide group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, a peptide group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediyloxycarbonyloxy group, an alkanediylthio group, an alkanediylsulfonyl group, an alkanediylamino group, an alkanediylpeptide group, and a group combining two or more of these groups. These substituted groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0016] m4 is preferably 1, 2 or 3, more preferably 1 or 2, and even more preferably 1. R 4 is 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 alkyl group may be replaced with -O- or -CO-), 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 alkyl group may be replaced with -O- or -CO-), still more preferably a fluorine 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-), still more preferably a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 4 carbon atoms, a hydroxy group, or an alkoxy group having 1 to 3 carbon atoms, and still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group, or a trifluoromethyl group.

[0017] R 5 X included in1 is *-CO-O-, *-O-CO-O- or *-O- (where * is L 2 or L 11 It is preferable that the bond is R 5 X included in 2 *-CO-O-, *-O-CO- or *-O-(* is L 2 It is preferable that the bond is

[0018] R 5 L included in 11 and L 12 Examples of the hydrocarbon group in include linear or branched chain hydrocarbon groups such as alkanediyl groups, monocyclic or polycyclic (including spiro rings, fused rings, or bridged rings) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and may also be groups combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and an alkanediyl group). The hydrocarbon group preferably has 1 to 24 carbon atoms, more preferably 1 to 20, and even more preferably 1 to 18. Examples of the alkanediyl group include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, and heptadecane-1,17-diyl groups; Examples of branched alkanediyl groups include ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl. The terminal of the branched alkanediyl group may be an alkyl group such as a methyl group. The chain hydrocarbon group may have 1 to 24 carbon atoms, preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 10, still more preferably 1 to 9, even more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following groups: The binding site can be any position. TIFF2026042751000012.tif42165Specifically, the alicyclic hydrocarbon group may be a monocyclic divalent alicyclic hydrocarbon group such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, or a cyclooctane-1,5-diyl group; Examples of such divalent alicyclic hydrocarbon groups include cycloalkyl groups such as norbornane-1,4-diyl, norbornane-2,5-diyl, adamantane-1,5-diyl, adamantane-2,6-diyl, spirocyclohexane-1,2'-cyclopentane, and spiroadamantane-2,3'-cyclopentane, and polycyclic cycloalkanediyl groups such as spiro rings each having a cycloalkyl group bonded to a norbornyl or adamantyl group via a spiro bond. The number of carbon atoms in the alicyclic hydrocarbon group may be 3 to 24, preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. Examples of the aromatic hydrocarbon group include arylene groups such as a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, etc. The aromatic hydrocarbon group may have 6 to 24 carbon atoms, preferably 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. Examples of the group combining two or more groups include a group combining an alicyclic hydrocarbon group with an alkanediyl group, a group combining an aromatic hydrocarbon group with an alkanediyl group, a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and an alkanediyl group. In the combination, two or more types of each of the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may be combined. In addition, when any group is X 1 or X 2 may be bound to Examples of groups combining an alicyclic hydrocarbon group and an alkanediyl group include -divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-alkanediyl group-, and -alkanediyl group-divalent alicyclic hydrocarbon group-. Examples of groups combining an aromatic hydrocarbon group and an alkanediyl group include -divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-alkanediyl group-, and -alkanediyl group-divalent aromatic hydrocarbon group-. Examples of groups combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group include -aromatic hydrocarbon group-alicyclic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-. L 11 and L 12 -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms is -O-, -S-, -SO2-, -SO-, -NR 6 It may be replaced by - or -CO-. L 11 and L 12 The -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms is -O-, -S-, -SO2-, -SO-, -NR 6 When it is replaced with - or -CO-, the number of carbon atoms before the replacement is regarded as the number of carbon atoms of the hydrocarbon group. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR 6 The group substituted for - or -CO- is L 1and L 2 Examples include the same as those exemplified above.

[0019] L 11 and L 12 Examples of the substituent that may be possessed by L include a halogen atom, a cyano group, and a nitro group. 11 and L 12 However, in the case of a group in which an alicyclic hydrocarbon group or an aromatic hydrocarbon group is combined with a chain hydrocarbon group such as an alkyl group, the chain hydrocarbon group such as an alkyl group can be substantially used as a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. 11 and L 12 The -CH2- contained in the chain hydrocarbon group such as the alkyl group contained in 6 - or -SO2-, L 11 can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkoxyalkoxy group, an alkylamino group, an amino group, a thiol group, an alkylthio group, an alkylsulfonyl group, or an alkylpeptide group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L 11 and L 12 The substituent in is preferably an alkyl group having 1 to 4 carbon atoms, a hydroxy group or a halogen atom, more preferably an alkyl group having 1 to 4 carbon atoms or a halogen atom, and further preferably a methyl group or a fluorine atom.

[0020] L 11 Examples of the alkyl group include an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO-, -NR 6- or -SO2-) or a group combining a chain hydrocarbon group of 1 to 10 carbon atoms which may have a substituent and a cyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent (-CH2- in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 6 - or -CO-), preferably an alkanediyl group having 1 to 10 carbon atoms (-CH2- contained in the alkanediyl group may be replaced with -O- or -CO-) or a group combining an alkanediyl group having 1 to 4 carbon atoms with an alicyclic hydrocarbon group having 3 to 12 carbon atoms (-CH2- contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced with -O- or -CO-), more preferably an alkanediyl group having 1 to 6 carbon atoms, even more preferably an alkanediyl group having 1 to 3 carbon atoms, and even more preferably a methylene group. L 12 Examples of the alkyl group include 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 by -O- or -CO-), a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO-, -NR 6 - or -SO2-) or a group combining a chain hydrocarbon group of 1 to 10 carbon atoms which may have a substituent and a cyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent (-CH2- in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 6- or -CO-), preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (-CH2- contained in the alkanediyl group may be replaced with -O- or -CO-), more preferably a single bond or a straight-chain alkanediyl group having 1 to 6 carbon atoms, even more preferably a single bond or a straight-chain alkanediyl group having 1 to 3 carbon atoms, and even more preferably a single bond or a methylene group.

[0021] R 10 represents a group containing a cyclic ether structure. The cyclic ether structure is preferably a cyclic ether structure having 2 to 5 carbon atoms, and more preferably a cyclic ether structure having 2 or 3 carbon atoms. Examples of the cyclic ether structure include a structure containing an oxirane ring, a structure containing an oxetane ring, a structure containing a 5-membered ether ring having 4 carbon atoms, and a structure containing a 6-membered ether ring having 5 carbon atoms. Of these, a 3-membered ether ring having 2 carbon atoms (oxirane ring) or a 4-membered ether ring having 3 carbon atoms (oxetane ring) is preferred.

[0022] Examples of the cyclic ether structure having 2 or 3 carbon atoms include a group represented by formula (IA) or a group represented by formula (IB). Examples of the cyclic ether structure having 2 to 4 carbon atoms include a group represented by formula (IC). TIFF2026042751000013.tif31114 [In formula (IA) and formula (IB), R A represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R A are either the same or different. s1 represents 1 or 2. t1 represents 0 or 1, provided that the sum of s1 and t1 is 1 or 2. L 12A represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -CO-, -NR 7It may be replaced by -, -SO- or -SO2-. L 13A represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -CO-, -SO-, and -NR 7 It may be replaced by - or -SO2-. R 7 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * denotes a binding site.] TIFF2026042751000014.tif3348[In formula (IC), R A represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R A are either the same or different. s12 represents an integer of 0 to 2. t12 represents an integer of 0 to 2, provided that the sum of s12 and t12 is an integer of 0 to 2. L 13A represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group is not selected from -O-, -S-, -CO-, -SO-, and -NR 7 It may be replaced by - or -SO2-. R 7 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * denotes a binding site.]

[0023] L 12A and L 13A Examples of the hydrocarbon group having 1 to 36 carbon atoms include aliphatic hydrocarbon groups (chain hydrocarbon groups such as alkanediyl groups, alkenediyl groups, alkynediyl groups, alkanetriyl groups, alkenetriyl groups, and alkyntriyl groups, and monocyclic or polycyclic alicyclic hydrocarbon groups), aromatic hydrocarbon groups, and the like, and may be a hydrocarbon group formed by combining two or more of these groups. 12A is a divalent hydrocarbon group, and L 13A is a trivalent hydrocarbon group. 12Aand L 13A The -CH2- contained in the hydrocarbon group in 7 It may be replaced by - or -SO2-. Examples of the alkanediyl group include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, and a dodecane-1,12-diyl group; Branched alkanediyl groups such as ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-2,2-diyl, pentane-2,4-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl groups. Examples include: Examples of the alkanetriyl group include groups in which one hydrogen atom has been removed from the above-mentioned alkanediyl group. Examples of the alkenediyl group include an ethenediyl group, a propenediyl group, an isopropenediyl group, a butenediyl group, an isobutenediyl group, a tert-butenediyl group, a pentenediyl group, a hexenediyl group, a heptenediyl group, an octenediyl group, an isooctenediyl group, and a nonenediyl group. Examples of the alkenetriyl group include groups in which one hydrogen atom has been removed from the above-mentioned alkenediyl group. Examples of the alkynediyl group include an ethynediyl group, a propynediyl group, an isopropynediyl group, a butynediyl group, an isobutynediyl group, a tert-butynediyl group, a pentynediyl group, a hexynediyl group, an octynediyl group, and a nonynediyl group. Examples of the alkynetriyl group include groups in which one hydrogen atom has been removed from the above-mentioned alkynediyl group. The chain hydrocarbon group may have 1 to 24 carbon atoms, preferably 1 to 12, more preferably 1 to 9, even more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3.

[0024] L 12A and L 13A The -CH2- contained in the hydrocarbon group is -O-, -CO-, -S-, -SO-, -NR 7 If it is replaced with - or -SO2-, the number of carbon atoms before replacement is L 12A and L 13A The total number of carbon atoms in the hydrocarbon group is 1. The number may be 1 or 2 or more. R 7 is R 6 Examples include the same as those exemplified above. The -CH2- contained in the alkanediyl group may be -O-, -S-, -CO-, -SO-, or -NR 7 The group substituted for - or -SO2- is L 12 Examples include the same as those exemplified above. The substitutions in the alkenediyl group and alkynediyl group may include a carbon-carbon double bond or a carbon-carbon triple bond at any position in the above-mentioned examples of substitutions in the alkanediyl group.

[0025] The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples thereof include the groups shown below: The bonding site may be at any position. TIFF2026042751000015.tif42165Specifically, examples of monocyclic alicyclic hydrocarbon groups include monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, cyclohexene-3,6-diyl, and cyclooctane-1,5-diyl; examples of polycyclic alicyclic hydrocarbon groups include norbornane-1,4-diyl, norbornane-1,5-diyl, and and polycyclic cycloalkanediyl groups such as 5-norbornene-2,3-diyl, adamantane-1,5-diyl, and adamantane-2,6-diyl; cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane and spiroadamantane-2,3'-cyclopentane; and spiro rings having a cycloalkyl group bonded to a norbornyl group or an adamantyl group via a spiro bond. Further examples include groups in which one hydrogen atom has been removed from the above groups. The alicyclic hydrocarbon group may have 3 to 24 carbon atoms, preferably 3 to 18 carbon atoms, more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms. In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be -O-, -S-, -CO-, -SO-, -NR 7 The group substituted with - or -SO2- includes the same groups as those exemplified in this specification, within the upper limit of the carbon number. Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, and a phenanthrylene group. Further examples include groups in which one hydrogen atom has been removed from the above groups. The aromatic hydrocarbon group may have 6 to 24 carbon atoms, preferably 6 to 18 carbon atoms, more preferably 6 to 14 carbon atoms, and even more preferably 6 to 10 carbon atoms. The -CH2- contained in the hydrocarbon group can be -O-, -S-, -CO-, -SO-, or -NR 7 When the hydrocarbon group is substituted with - or -SO2-, the number of carbon atoms before the substitution is taken as the total number of carbon atoms in the hydrocarbon group.

[0026] Examples of hydrocarbon groups that combine two or more groups include groups that combine a chain hydrocarbon group with an alicyclic hydrocarbon group and / or an aromatic hydrocarbon group, and in the combination, two or more types of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined. Examples include -alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-aromatic hydrocarbon group-, -aromatic hydrocarbon group-alkanediyl group-, etc. When any of the groups is an oxygen atom, a carbonyl group, or L, 12 may be bound to

[0027] L 12A and L 13A Examples of the substituent on the hydrocarbon group include a halogen atom, a cyano group, a hydroxy group, a carboxy group, an alkoxy group having 1 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyloxy group having 2 to 13 carbon atoms, an alkoxycarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyl group having 2 to 13 carbon atoms, an alkylcarbonyloxy group having 2 to 13 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkoxy group having 2 to 11 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, a nitro group, an amine, an amino group, an alkylamino group having 2 to 11 carbon atoms, and combinations thereof. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkoxy group having 1 to 12 carbon atoms include 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, and a dodecyloxy group. The alkoxycarbonyl group having 2 to 13 carbon atoms, the alkylcarbonyl group having 2 to 13 carbon atoms, and the alkylcarbonyloxy group having 2 to 13 carbon atoms represent groups in which a carbonyl group or a carbonyloxy group is bonded to the above-mentioned alkyl group or alkoxy group. Examples of the alkoxycarbonyl group having 2 to 13 carbon atoms include a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group having 2 to 13 carbon atoms include an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group having 2 to 13 carbon atoms include an acetyloxy group, a propionyloxy group, and a butyryloxy group. Examples of the cycloalkyl group having 3 to 12 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the cycloalkoxy group having 3 to 12 carbon atoms include an epoxyl group and an oxetanyl group. Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include a phenyl group and a naphthyl group. Examples of the alkylamino group having 2 to 11 carbon atoms include a methylamino group, an ethylamino group, a dimethylamino group, and a diethylamino group. L 12A and L 13A The hydrocarbon group in may have one or more substituents.

[0028] In the case of formula (IA), L 12A represents a single bond, a chain hydrocarbon group having 1 to 8 carbon atoms (the -CH2- contained in the chain hydrocarbon group is not limited to -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-) or a group in which a chain hydrocarbon group having 1 to 8 carbon atoms is combined with an alicyclic hydrocarbon group having 3 to 18 carbon atoms (the -CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-), and examples thereof include a single bond, an alkanediyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl group may be -O-, -S-, -SO2-, -SO-, -NR 7- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-) or a group in which an alkanediyl group having 1 to 6 carbon atoms is combined with an alicyclic hydrocarbon group having 3 to 18 carbon atoms (the -CH2- contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO2, -SO-, -NR 7 - 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.

[0029] In the case of formula (IB) or formula (IC), L 13A represents a chain hydrocarbon group having 1 to 8 carbon atoms (the -CH2- contained in the chain hydrocarbon group is not limited to -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-) or a group in which a chain hydrocarbon group having 1 to 8 carbon atoms is combined with an alicyclic hydrocarbon group having 3 to 18 carbon atoms (the -CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-), and an alkanetriyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkanetriyl group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 7- or -CO-) or a group in which an alkanediyl group having 1 to 6 carbon atoms is combined with an alicyclic hydrocarbon group having 3 to 18 carbon atoms (the -CH2- contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced with -O-, -S-, -SO2-, -SO-, -NR 7 - or -CO-), more preferably an alkanetriyl group having 1 to 6 carbon atoms, even more preferably an alkanetriyl group having 1 to 3 carbon atoms, and even more preferably a methine group.

[0030] s1 is preferably 1, t1 is preferably 1, and the sum of s1 and t1 is preferably 2. s12 is preferably 0 or 1, t12 is preferably 0 or 1, and the sum of s12 and t12 is preferably 0 or 1. The group represented by formula (IA) is preferably a group represented by the following formula: TIFF2026042751000016.tif19146The group represented by formula (IB) or formula (IC) is preferably a group represented by the following formula: TIFF2026042751000017.tif23141

[0031] In the group represented by formula (IA), u1 is preferably 1 or more, and at least one R A L 12A It is preferable that u1 is 1 and R A L 12A The group bonded to the carbon atom adjacent to is represented by the formula: TIFF2026042751000018.tif2839R A Examples of the saturated hydrocarbon group include chain saturated hydrocarbon groups such as alkyl groups, alicyclic saturated hydrocarbon groups, and groups in which two or more of these groups are combined. R AExamples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, etc. The number of carbon atoms in the chain saturated hydrocarbon group is preferably 1 to 9, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. The alicyclic saturated hydrocarbon group may be any of monocyclic, polycyclic, and spirocyclic. Examples of the alicyclic saturated hydrocarbon group include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclononyl, cyclodecyl, and cyclododecyl, and polycyclic cycloalkyl groups such as norbornyl and adamantyl. The number of carbon atoms in the alicyclic saturated hydrocarbon group is preferably 3 to 10, more preferably 3 to 8, and even more preferably 3 to 6. The combined group may be a group in which one chain saturated hydrocarbon group and one alicyclic saturated hydrocarbon group are combined, or a group in which two or more of either or two or more of both are combined.

[0032] R 10 Examples of the group include the following groups: TIFF2026042751000019.tif127137R 10 is preferably a group represented by formula (IA), a group represented by formula (IB) or a group represented by formula (IC), and more preferably a group represented by formula (IA) or a group represented by formula (IB). R 5 are each independently -OR 10 , -CO-OR 10 , -O-CO-OR 10 , -O-CO-R 10 or -OL 11 -CO-OR 10 It is preferable that: m5 is preferably 1, 2 or 3, more preferably 1 or 2, and even more preferably 1. L 2 -R 5 The bonding position of L in the benzene ring1 The bonding positions may be any of the o-position, m-position and p-position relative to the bonding position of the formula (I), but at least one of them is preferably the o-position or p-position. R 4 The bonding position of L in the benzene ring 1 The bonding positions may be any of the o-position, m-position, and p-position relative to the bonding position of the formula (I), but at least one is preferably the o-position or m-position, and more preferably the o-position. R 4 When an iodine atom is present as a bond, the bonding position of the iodine atom is 1 The bonding positions may be any of the o-position, m-position, and p-position relative to the bonding position of the formula (I), but at least one is preferably the o-position or m-position, and more preferably the o-position.

[0033] Examples of the anion (I) include anions represented by the following formulae (Ia-1) to (Ia-30). TIFF2026042751000020.tif231160

[0034] TIFF2026042751000021.tif173155

[0035] [Cation (I)] Z in formula (I) + Examples of the organic cation include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations 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). TIFF2026042751000022.tif84160[Formula (b2-1) to formula (b2-5), R b4 ~R b6each independently represent a chain hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, a hydrogen atom contained in the chain hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5 and may be bonded to each other to form a ring together with the sulfur atom to which they are attached, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-. R b7 and R b8 each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m7 and n8 each independently represent an integer of 0 to 5; When m7 is 2 or more, multiple R b7 may be the same or different, and when n8 is 2 or more, multiple R b8 may be the same or different. R b9 and R b10 each independently represents a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 and may be bonded to each other to form a ring together with the sulfur atom to which they are attached, and -CH2- contained in the ring may be replaced with -O-, -S- or -CO-. R b11represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may be bonded to each other to form a ring including the -CH-CO- to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b13 ~R b18 and 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. 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-. R b27 ~R b29 each independently represents a hydrogen atom or a group containing an acid labile group. L b31 and L b41 ~L b43 each independently represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer of 0 to 5. q2 and r2 each independently represent an integer of 0 to 4; u2 represents 0 or 1. When o2 is 2 or more, multiple R b13are the same or different, and when p2 is 2 or more, multiple R b14 are the same or different, and when q2 is 2 or more, multiple R b15 are the same or different, and when r2 is 2 or more, multiple R b16 are the same or different, and when s2 is 2 or more, multiple R b17 are the same or different, and when t2 is 2 or more, multiple R b18 are the same or different. o21, p22, q23, r24, t25 and s26 each independently represent an integer of 0 to 4. When o21, p22, q23, r24, t25 and s26 are each 2 or more, multiple R b21 ~R b26 are the same or different. u3 represents an integer of 1 to 3, and satisfies 1≦u3+q23≦5. u4 and u5 each independently represent an integer of 0 to 3, and satisfy 0≦u4+o21≦5 and 0≦u5+p22≦5. When u3, u4, and u5 each represent 2 or more, the groups in the parentheses are the same or different.

[0036] When u2 is 0, any one of o2, p2, q2, and r2 is 1 or more, and R b13 ~R b16 At least one of o2, p2, s2, t2, q2 and r2 is preferably a halogen atom, and when u2 is 1, any one of o2, p2, s2, t2, q2 and r2 is 1 or more, and R b13 ~R b18 At least one of these is preferably a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, and more preferably 1. When u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom. The aliphatic hydrocarbon group refers to a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl. In particular, R b9 ~R b12 The chain hydrocarbon group preferably has 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and cyclodecyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups: TIFF2026042751000023.tif11157 In particular, R b9 ~R b12 The alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, and more preferably has 4 to 12 carbon atoms. Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-methyladamantan-2-yl group, a 2-ethyladamantan-2-yl group, a 2-isopropyladamantan-2-yl group, a methylnorbornyl group, an isobornyl group, etc. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms in the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The fluorinated alkyl group refers to an alkyl group having 1 to 12 carbon atoms and a fluorine atom, and examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluorobutyl group, etc. The number of carbon atoms in the fluorinated alkyl group is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 4. Examples of aromatic hydrocarbon groups include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, etc. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples thereof include aromatic hydrocarbon groups having a chain hydrocarbon group (such as a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, etc.) and aromatic hydrocarbon groups having an alicyclic hydrocarbon group (such as a p-cyclohexylphenyl group, a p-adamantylphenyl group, etc.). When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. Examples of aromatic hydrocarbon groups in which hydrogen atoms are substituted with alkoxy groups include p-methoxyphenyl groups. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, an isopropylcarbonyloxy group, a butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, and a 2-ethylhexylcarbonyloxy group. R b4 and R b5and bond to each other together with the sulfur atom to which they are bonded to form a ring which may be monocyclic, polycyclic, aromatic, non-aromatic, saturated, or unsaturated. This ring may be a ring having 3 to 18 carbon atoms, preferably a ring having 4 to 18 carbon atoms. The ring containing a sulfur atom may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring, for example, the following rings. * represents a bonding site. TIFF2026042751000024.tif24142R b9 and R b10 The ring formed by these together may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring may be a 3- to 12-membered ring, preferably a 3- to 7-membered ring. Examples thereof include a thiolan-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and a 1,4-oxathian-4-ium ring. R b11 and R b12 The ring formed by combining these may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include a 3- to 12-membered ring, and preferably a 3- to 7-membered ring. Examples include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring. R b27 ~R 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, and R c30 represents an acid labile group. R b27 ~R b29 The acid labile group includes groups represented by formula (1) or (2).

[0037] Among the cations (b2-1) to (b2-5), the cation (b2-1), the cation (b2-4) or the cation (b2-5) is preferred. Examples of the cation (b2-1) include the following cations. TIFF2026042751000025.tif172164

[0038] TIFF2026042751000026.tif58162 Examples of the cation (b2-2) include the following cations. TIFF2026042751000027.tif18150Examples of the cation (b2-3) include the following cations. TIFF2026042751000028.tif26140Examples of the cation (b2-4) include the following cations. TIFF2026042751000029.tif121163 Examples of the cation (b2-5) include the following cations. TIFF2026042751000030.tif101164

[0039] Specific examples of the salt (I) include salts formed by any combination of the above-mentioned cations and anions. Specific examples of the salt (I) are shown in the table below. In the table below, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation, and "~" indicates that the salt (I) corresponds to the anion (I). For example, salt (I-1) is a salt consisting of an anion represented by formula (Ia-1) and a cation represented by formula (b2-c-1), salt (I-2) is a salt consisting of an anion represented by formula (Ia-2) and a cation represented by formula (b2-c-1), and salt (I-26) is a salt consisting of an anion represented by formula (Ia-1) and a cation represented by formula (b2-c-10). TIFF2026042751000031.tif4283 [Table 1] TIFF2026042751000033.tif234159

[0040] Among these, salt (I) is preferably a salt obtained by combining an anion represented by any one of formulas (Ia-1) to (Ia-30) with a cation represented by any one of formulas (b2-c-1), (b2-c-10), (b2-c-13), (b2-c-14), (b2-c-18) to (b2-c-20), (b2-c-27), (b2-c-30), (b2-c-31), (b2-c-47), (b2-c-48), and (b2-c-50) to (b2-c-79).

[0041] <Method for producing salt (I)> Salt (I) can be produced, for example, by reacting a salt represented by formula (I-a1), a salt represented by formula (I-a2), or a salt represented by formula (I-a3) with a compound represented by formula (Ib) in a solvent in the presence of a catalyst. TIFF2026042751000034.tif89152 (wherein the symbols other than those shown below have the same meanings as above, X′ represents an oxygen atom or —NR 6 nm2 represents 0 or 1. L 1 'L 1 From -(CO) nm2 -O-(CO) 1-nm2 represents a group excluding -.) Examples of solvents used in this reaction include chloroform and acetonitrile. Examples of the catalyst include carbonyldiimidazole, 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride, and the like. The reaction temperature is usually 5°C to 80°C, and the reaction time is usually 0.5 to 24 hours.

[0042] Examples of salts represented by formula (I-a1) include the salts represented by the following formulas, which are readily available on the market and can also be easily produced by known production methods. TIFF2026042751000035.tif54159

[0043] Examples of salts represented by formula (I-a2) include the salts represented by the following formulas, which are readily available on the market and can also be easily produced by known production methods. TIFF2026042751000036.tif76163

[0044] Examples of salts represented by formula (I-a3) include the salts represented by the following formulas, which are readily available on the market and can also be easily produced by known production methods. TIFF2026042751000037.tif132168

[0045] Examples of the compound represented by formula (I1-b) include compounds represented by the following formula, which are readily available on the market and can also be easily produced by known production methods. TIFF2026042751000038.tif103160

[0046] [Acid Generator] The acid generator of the present invention may contain one kind of salt (I) or may contain two or more kinds of salt (I). The acid generator of the present invention may contain, in addition to the salt (I), a known compound that acts as an acid generator in the resist field (hereinafter, sometimes referred to as "compound (B)" or "acid generator (B)"). The compound (B) may be used alone or in combination of two or more.

[0047] Compound (B) may be either a nonionic compound or an ionic compound. Examples of nonionic compounds include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), etc. Examples of ionic compounds include onium salts containing onium cations (e.g., diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Examples of anions of onium salts include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, and carboxylate anions. The compound (B) may be a part of a structural unit that constitutes the resin contained in the resist composition of the present invention, such as the structural unit (a7) described below. Compound (B) that can be used is a compound that generates an acid when exposed to radiation, such as those described in JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Pat. No. 3,779,778, U.S. Pat. No. 3,849,137, German Patent No. 3,914,407, and European Patent No. 126,712. Compounds produced by known methods may also be used. Compound (B) may be an acid generator having an acid labile group. For example, the compound or resin that serves as the acid generator may contain a partial structure that forms an acid labile group, and the acid labile group preferably contains group (1) or group (2) described below. When the resist composition of the present invention contains a compound having an acid labile group, it does not necessarily need to contain a resin that contains a structural unit having an acid labile group.

[0048] Preferred embodiments of compound (B) include a salt represented by formula (B1) (hereinafter sometimes referred to as "salt (B1)" or "acid generator (B1)") and a salt represented by formula (B2) (hereinafter sometimes referred to as "salt (B2)" or "acid generator (B2)"). TIFF2026042751000039.tif1492[In formula (B1), L b1 represents a single bond or an (nb1+1)-valent hydrocarbon group which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced with -O-, -S-, -CO-, -SO- or -SO2-. L b2 represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. Y b1 represents an optionally substituted methyl group or an optionally substituted cyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO- or -CO-. nb1 represents an integer of 1 to 6. When nb1 is 2 or more, the groups in the parentheses may be the same or different. Z1 + represents an organic cation.

[0049] L b1 The (nb1+1)-valent hydrocarbon group is a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, or a monovalent group that combines two or more of these groups, from which nb1 hydrogen atoms have been removed to form one or more L b2 The hydrocarbon group may have 1 to 48 carbon atoms, preferably 1 to 42, more preferably 1 to 36, even more preferably 1 to 30, still more preferably 1 to 24, and even more preferably 1 to 18. Examples of the chain hydrocarbon group include groups in which nb hydrogen atoms have been removed from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, and heptadecyl groups. Examples of the alkenyl group include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl groups. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 24, even more preferably 1 to 20, still more preferably 1 to 18, even more preferably 1 to 12, and even more preferably 1 to 10. Examples of the alicyclic hydrocarbon group include groups in which nb hydrogen atoms have been removed from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of polycyclic cycloalkyl groups include cycloalkyl groups having a bridged structure, cycloalkyl groups in which two or more rings are fused, and cycloalkyl groups in which two rings are bonded via a spiro bond. Examples of cycloalkyl groups having a bridged structure include a norbornyl group and an adamantyl group. Examples of cycloalkyl groups in which two or more rings are fused include a bicyclo[4.4.0]decanyl group and a steroid group (steroid skeleton). Examples of cycloalkyl groups in which two rings are bonded via a spiro bond include spirocyclic cycloalkyl groups in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group is bonded via a spiro bond to a cycloalkyl group having 5 to 8 carbon atoms. A double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, alicyclic hydrocarbon groups represented by the following formulas are included. TIFF2026042751000040.tif42165When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 24, more preferably 3 to 20, even more preferably 3 to 18, still more preferably 3 to 12, even more preferably 3 to 10, and still more preferably 3 to 8.When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 6 to 24, more preferably 6 to 20, even more preferably 6 to 18, still more preferably 6 to 12, and even more preferably 7 to 12. Examples of aromatic hydrocarbon groups include groups in which nb1 hydrogen atoms have been removed from an aryl group. Examples of aryl groups include phenyl, naphthyl, anthryl, biphenyl, and fluorenyl groups. More specifically, examples of aromatic hydrocarbon groups include those represented by the following formulas: TIFF2026042751000041.tif1187The number of carbon atoms in the aromatic hydrocarbon group is preferably 4 to 24, more preferably 4 to 20, even more preferably 4 to 18, still more preferably 5 to 14, even more preferably 5 to 10, and even more preferably 6 to 10. L b1 When -CH2- in the hydrocarbon group is replaced with -O-, -CO-, -S-, -SO- or -SO2-, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the hydrocarbon group. L b1Among the hydrocarbon groups in the above, groups in which -CH2- in a chain 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 carboxy group (a group in which -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 ... Examples of such a group include an alkyl group in which -CH- at any position is replaced with -CO-), an alkylcarbonyloxy group (a group in which -CH-CH- at any position is replaced with -CO-O-), an alkanediyloxy group (a group in which -CH- at any position is replaced with -O-), an alkanediyloxycarbonyl group (a group in which -CH- at any position is replaced with -O-CO-), an alkanediylcarbonyl group (a group in which -CH- at any position is replaced with -CO-), and an alkanediylcarbonyloxy group (a group in which -CH- at any position is replaced with -CO-) within the range permitted by the upper limit of the number of carbon atoms. Examples of such a substituted group include the same groups as those exemplified in this specification. L b1Among the hydrocarbon groups, examples of groups in which -CH- in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these groups is replaced with -O-, -CO-, -S-, -SO-, or -SO- include groups containing structures such as cyclic ether, cyclic ketone, cyclic ester (lactone ring), cyclic thioether, cyclic acetal, and cyclic sulfonate ester (sultone ring), as well as groups derived from a furan ring or a thiophene ring. These substituted groups include the same groups exemplified in this specification, within the range permitted by the upper limit of the carbon number. Examples of groups combining two or more groups, namely, a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group, include a group combining the above-mentioned chain hydrocarbon group with the above-mentioned alicyclic hydrocarbon group, a group combining the above-mentioned chain hydrocarbon group with the above-mentioned aromatic hydrocarbon group, a group combining the above-mentioned alicyclic hydrocarbon group with the above-mentioned aromatic hydrocarbon group, and a group combining the above-mentioned chain hydrocarbon group with the above-mentioned alicyclic hydrocarbon group with the above-mentioned aromatic hydrocarbon group. The group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group may be a fused ring. L b2 Examples of the divalent hydrocarbon group include a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group formed by combining two or more of these groups. A monovalent hydrocarbon group can be obtained by removing one hydrogen atom to form Y b1 Examples of such groups include groups that bond to the following: L b2 The divalent chain hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group formed by combining two or more of these groups are each, within the range permitted by the upper limit of the number of carbon atoms, L b1 Examples of the monovalent hydrocarbon group include a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, and a monovalent group obtained by combining two or more of these groups and removing one hydrogen atom from them. L b1 and L b2 Examples of the substituent that the hydrocarbon group may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L b1 and L b2When 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 substantially a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. b1 and L b2 The -CH2- of the chain hydrocarbon group contained in the hydrocarbon group is replaced by -O-, -CO-, -S-, -SO- or -SO2-, thereby forming L b1 and L b2 The hydrocarbon group may substantially have a substituent such as a hydroxy group, a carboxy group, a carbonyl group, an oxycarbonyl group, a carbonyloxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, an alkylthio group, or an alkylsulfonyl group. Y b1 Examples of the cyclic hydrocarbon group include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which an alicyclic hydrocarbon group and an aromatic hydrocarbon group are combined. Y b1 The alicyclic hydrocarbon group and the aromatic hydrocarbon group are, respectively, L b1 Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups include those similar to those exemplified in 1., and when they have no substituent, they may be monovalent alicyclic hydrocarbon groups and aromatic hydrocarbon groups. Y b1 Examples of the substituent that the methyl group and cyclic hydrocarbon group may have include a halogen atom, a cyano group, a nitro group, or a hydrocarbon group having 1 to 18 carbon atoms that may have a halogen atom, a cyano group, or a nitro group (-CH2- contained in the hydrocarbon group may be replaced with -O-, -S-, -CO-, -SO-, or -SO2-). b1 The number of carbon atoms in the hydrocarbon group that the methyl group and the cyclic hydrocarbon group may have is b1 The carbon number of the methyl group and the cyclic hydrocarbon group is not included in the carbon number of the methyl group and the cyclic hydrocarbon group. The halogen atoms include L b1 and L b2 The halogen atoms exemplified as the substituents of Y are the same as those exemplified as the halogen atoms of Y. b1Examples of the hydrocarbon group having 1 to 18 carbon atoms that may be substituted on the methyl group and cyclic hydrocarbon group include chain hydrocarbon groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups combining these groups. Examples of the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups combining two or more of these groups include, within the range permitted by the upper limit of the number of carbon atoms, L b1 Examples of the groups include the chain hydrocarbon groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups in which two or more of these groups are combined, as exemplified above. Also, Y b1 Examples of the methyl group and the hydrocarbon group having 1 to 18 carbon atoms that may have a substituent, in which -CH2- is replaced by -O-, -S-, -CO-, -SO- or -SO2-, are, within the range permitted by the upper limit of the number of carbon atoms, L b1 Examples of the hydrocarbon group include the same groups as those exemplified above in which -CH2- in the hydrocarbon group is replaced with -O-, -S-, -CO-, -SO- or -SO2-. b1 The hydrocarbon group having 1 to 18 carbon atoms that the methyl group and cyclic hydrocarbon group may have as a substituent may constitute a protecting group or leaving group (acid labile group or base labile group) commonly used in the art. The anion of the salt represented by formula (B1) is preferably an anion represented by the following formula (B1-A1) (hereinafter, sometimes referred to as "anion (B1-A1)") or an anion represented by formula (B1-A2) (hereinafter, sometimes referred to as "anion (B1-A2)"). TIFF2026042751000042.tif30126[In formula (B1-A1), L b2 and Y b1 has the same meaning as in formula (B1). Q b1 , Q b2 , Q b3 and Q b4 each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. z1 represents an integer of 0 to 6. When z1 is 2 or more, the groups in the parentheses may be the same or different. X 1 represents -O-CO-, -CO-O-, -O-CO-O- or -O-. L b3 represents a single bond or an (nb2+1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. nb2 represents an integer of 1 to 3. When nb2 is 2 or greater, the groups in the parentheses may be the same or different.] Q b1 , Q b2 , Q b3 and Q b4 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. Q b1 , Q b2 , Q b3 and Q b4 Examples of the perfluoroalkyl group include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. Q b1 and Q b2 Q b1 and Q b2 At least one of the groups preferably contains a fluorine atom or a perfluoroalkyl group, more preferably a fluorine atom or a perfluoroalkyl group, even more preferably a fluorine atom or a trifluoromethyl group, and even more preferably both are fluorine atoms. Q b3 and Q b4 are each preferably independently a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b3is preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b4 is preferably a hydrogen atom or a fluorine atom. z1 is preferably an integer of 0 to 3, and more preferably 0, 1 or 2. X 1 is preferably —O—CO— or —CO—O—.

[0050] L b3 As the hydrocarbon group in the formula (B1), within the range permitted by the upper limit of the number of carbon atoms, b1 The same hydrocarbon groups as those exemplified above can be mentioned. L b3 is preferably a single bond, an optionally substituted chain hydrocarbon group of 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), an optionally substituted alicyclic hydrocarbon group of 3 to 18 carbon atoms (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO-, -SO- or -SO2-), an optionally substituted aromatic hydrocarbon group of 6 to 10 carbon atoms (-CH2- contained in the aromatic hydrocarbon group may be replaced with -O- or -S-), or a group comprising a combination of two or more of these groups, and more preferably a single bond, an optionally substituted chain hydrocarbon group of 1 to 6 carbon atoms, or a group represented by the following formula (Lb3-1): When -CH2- in the chain hydrocarbon group is replaced with -O- or -CO-, the number of -CH2- in the chain hydrocarbon group replaced with -O- or -CO- is preferably 1 to 4, and it is preferred that one -CH2-CH2- in the chain hydrocarbon group is replaced with -O-CO- or -CO-O-, or one -CH2-CH2-CH2- in the chain hydrocarbon group is replaced with -O-CO-O-. TIFF2026042751000043.tif1581[In formula (Lb3-1), nb2 has the same meaning as in formula (B1-A1). L b31represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms, and -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-, and the chain hydrocarbon group may have a substituent. W b3 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-, and -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-, and the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent. * and ** represent binding sites, * represents X 1 represents the binding site with In formula (Lb3-1), L b31 The chain hydrocarbon group of L is as long as the upper limit of the carbon number allows. b1 Examples of the chain hydrocarbon groups include the same groups as those exemplified above. In formula (Lb3-1), W b3 The alicyclic hydrocarbon group and aromatic hydrocarbon group of L are as long as the upper limit of the carbon number allows. b1 Examples of the alicyclic hydrocarbon groups and aromatic hydrocarbon groups are the same as those exemplified above. In formula (Lb3-1), L b31 The substituents which the chain hydrocarbon group of W may have and b3 The substituents that the alicyclic hydrocarbon group and aromatic hydrocarbon group may have are b1 Examples of the substituent that the hydrocarbon group may have include the same groups as the substituents exemplified above. L b31 is preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (-CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, W b3 Examples of the alicyclic hydrocarbon group and aromatic hydrocarbon group include the alicyclic hydrocarbon group and aromatic hydrocarbon group shown below. In the alicyclic hydrocarbon group and aromatic hydrocarbon group shown below, * and ** represent a bonding site, * represents X 1 or L b31represents a bonding site with L, and ** represents a hydrogen atom, a substituent, or L b2 represents a binding site with at least one ** b2 represents a bonding site with. In the alicyclic hydrocarbon groups represented below, -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO-, -SO-, or -SO2-. When -CH2- contained in the alicyclic hydrocarbon group is replaced with -O-, -S-, -CO-, -SO-, or -SO2-, it is preferable that an ether ring, ester ring (lactone ring), carbonate ester ring, sulfonate ester ring (sultone ring), or acetal ring is formed. TIFF2026042751000044.tif37163In the formula (B1-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 represents the binding site with L b21 , X 2 and L b22 The total number of carbon atoms is 12 or less. In formula (B1-A1), Y b1is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S-, -SO-, or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S-, -SO-, or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and even more preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (-CH2- in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S-, -SO-, or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, groups represented by the following formulae (Y1) to (Y36) are preferred. In formulas (Y1) to (Y36), R Yb is a hydrogen atom or Y b1 Among the substituents that the cyclic hydrocarbon group may have, R represents an alkyl group having 1 to 4 carbon atoms. Yc is a hydrogen atom or Y b1 represents a substituent that the cyclic hydrocarbon group of the formula (I) may have, and * represents a substituent that the cyclic hydrocarbon group of the formula (I) may have, b2 The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formulae may have other substituents, although not specifically shown in the following formulae. TIFF2026042751000045.tif83160

[0051] The anion represented by formula (B1-A1) is preferably an anion represented by formula (B1-A1-1) to formula (B1-A1-85) (hereinafter, sometimes referred to as "anion (B1-A1-1)" depending on the formula number), and more preferably an anion represented by any of formulas (B1-A1-1) to (B1-A1-4), (B1-A1-9), (B1-A1-10), (B1-A1-24) to (B1-A1-33), (B1-A1-36) to (B1-A1-40), and (B1-A1-47) to (B1-A1-85). TIFF2026042751000046.tif216160

[0052] TIFF2026042751000047.tif249151

[0053] TIFF2026042751000048.tif254157

[0054] where R i2 ~R i7 are each independently, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. i8 is, for example, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 has the same meaning as above. Specific examples of the anion represented by formula (B1-A1) include the anions described in JP-A-2010-204646.

[0055] Preferred anions represented by formula (B1-A1) include those represented by formulas (B1a-1) to (B1a-72). Of these, anions represented by any of formulas (B1a-1) to (B1a-4), (B1a-7) to (B1a-11), (B1a-14) to (B1a-30), and (B1a-35) to (B1a-70) are preferred. TIFF2026042751000049.tif182157

[0056] TIFF2026042751000050.tif252161

[0057] TIFF2026042751000051.tif90165

[0058] The anion represented by formula (B1-A2) is represented by the following formula: TIFF2026042751000052.tif23100[In formula (B1-A2), L b2 and Y b1 has the same meaning as in formula (B1). R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and one --CH.sub.2-- contained in the alkyl group may be replaced with --O-- or --CO--. nb4 represents an integer of 1 to 5. When nb4 is 2 or greater, the groups in the parentheses may be the same or different. nb3 represents an integer of 0 to 4. When nb3 is 2 or more, a plurality of R b1 may be the same or different from each other. However, 1≦nb4+nb3≦5 is satisfied.

[0059] In formula (B1-A2), L b2 and Y b1 Examples of the cyclic hydrocarbon group include, within the upper limit of the carbon number, L in formula (B1). b2 and Y b1 Examples of the cyclic hydrocarbon group are the same as those of L. b2 hydrocarbon group, Y b1 The substituents that the methyl group and the cyclic hydrocarbon group may have are also defined as follows: b2 hydrocarbon group, Y b1 Examples of the substituents that the methyl group and cyclic hydrocarbon group may have are the same as those listed above. These hydrocarbon groups, methyl groups and cyclic hydrocarbon groups may have one or more substituents. L b2 is preferably a chain hydrocarbon group having 1 to 12 carbon atoms (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and more preferably -CO-OL b41 -(L b41 is a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms, and -CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-. * is SO3- represents the bonding site with the benzene ring to which L is attached. b41 is preferably a single bond or a chain hydrocarbon group having 1 to 3 carbon atoms. ) and even more preferably *-CO-O-. Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and Y in formula (B1-A1) is b1 or L b1 More preferably, it is an alicyclic hydrocarbon group or an aromatic hydrocarbon group exemplified by the following: Specifically, it is preferably a group represented by the above formulas (Y1) to (Y36), and more preferably a group represented by the above formulas (Y1) to (Y19). Y b1 The substituents that the cyclic hydrocarbon group may have are preferably a halogen atom or an alkyl group having 1 to 6 carbon atoms (wherein -CH2- in the alkyl group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-), more preferably a fluorine atom, an iodine atom or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- in the alkyl group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-), even more preferably a fluorine atom, an iodine atom, a hydroxy group, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 4 carbon atoms, and even more preferably a fluorine atom, an iodine atom, a hydroxy group or an alkyl group having 1 to 4 carbon atoms. b1 The substituent of may constitute a protecting group or leaving group (acid labile group or base labile group) commonly used in the art.

[0060] In formula (B1-A2), nb4 is preferably an integer of 1 to 4, more preferably an integer of 1 to 3, even more preferably 1 or 2, and even more preferably 2. When nb4 is 1 or 2, -L b2 -Y b1 The bond position of SO3 - The following structure, which is substituted at the m-position of the benzene ring relative to the bonding position of TIFF2026042751000053.tif28106 [In the above formula, L b2 , Y b1 , R b1 , nb3 has the same meaning as in formula (B1-A2). In formula (B1-A2), when nb4 is 2 or more, a plurality of L b2 and Y b1 are preferably the same group.

[0061] R b1 Examples of the alkyl group having 1 to 6 carbon atoms include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 4, and more preferably 1 to 3. R b1 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of groups in which -CH- in an alkyl group is replaced with -O- or -CO- include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an oxy group, a carbonyl group, etc. These substituted groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. R b1are each independently preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms (wherein —CH2— contained in the alkyl group may be replaced with —O— or —CO—), more preferably a fluorine atom, an iodine atom or an alkyl group having 1 to 3 carbon atoms (wherein —CH2— contained in the alkyl group may be replaced with —O— or —CO—), and further preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group or a methyl group. nb3 is an integer of 0 to 4 (i.e., nb3-1 is an integer of 0 to 3), preferably an integer of 0 to 3, and more preferably an integer of 0 to 2. In one embodiment, nb3 is preferably 0. In another embodiment, nb3 is preferably 1 or 2. When nb3 is 1, R b1 is preferably a halogen atom, and R b1 is more preferably a fluorine atom or an iodine atom. When nb3 is 2, R b1 Preferably, one of R is a halogen atom and the other is a halogen atom or an alkyl group having 1 to 4 carbon atoms, b1 It is more preferable that one of the groups is a fluorine atom or an iodine atom, and the other is a fluorine atom, an iodine atom, or an alkyl group having 1 to 3 carbon atoms.

[0062] Examples of the anion represented by formula (B1-A2) include the following anions. Among them, the anions represented by formulas (B2a-1) to (B2a-32) are preferred, and the anions represented by formulas (B2a-1) to (B2a-11) and (B2a-16) to (B2a-26) are more preferred. The following anions are also preferred in the case of some R b1 is omitted, and may contain substituents not shown. TIFF2026042751000054.tif173159

[0063] Examples of the acid generator (B2) include salts represented by the following formula: TIFF2026042751000055.tif1192[In formula (B2), A 1 represents a nitrogen atom or a carbon atom. L b2’ represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. Y b1’ represents an optionally substituted methyl group or an optionally substituted cyclic hydrocarbon group having 3 to 24 carbon atoms, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. nb5 represents an integer of 2 or 3. When nb5 is 2, A 1 is a nitrogen atom, and when nb5 is 3, A 1 is a carbon atom. The groups in parentheses may be the same or different, and two groups in parentheses are bonded to form A 1 may form a ring containing: Z2 + represents an organic cation.

[0064] In formula (B2), L b2’ and Y b1’ Examples of the formula (B1-A1) include L b2 and Y b1 The same groups as those shown below can be mentioned. 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. 2 and X 3 each independently represents -O-, -CO-O-, -O-CO-, -O-CO-O- or -O-. W 2 represents an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-. * represents a bonding site with SO2. ) is preferred. Y b1 is preferably a methyl group having a fluorine atom or a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (-CH2- contained in the cyclic hydrocarbon group may be replaced with -O-, -CO-, -S-, -SO- or -SO2-), and more preferably a trifluoromethyl group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-, -S-, -CO-, -SO- or -SO2-), or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. Specifically, it is preferably a trifluoromethyl group or a group represented by formulae (Y1) to (Y36) exemplified in formula (B1-A1). In the anion of the salt represented by formula (B2), two -SO2-L b2 '-Y b1 When "A" and "B" are taken together to form a ring, examples of the anion include an anion represented by formula (B2'). TIFF2026042751000056.tif21112[In formula (B2'), A 1 , Y b1’ , L b2’ and nb5 have the same meaning as in formula (B2). W b4 represents a disulfonylimide ring or disulfonylmide ring having 2 to 12 carbon atoms which may have a fluorine atom.] W b4 The disulfonylimide ring or disulfonylmide ring preferably has 3 to 12 carbon atoms, more preferably 3 to 6 carbon atoms, and the hydrogen atom of the methylene group contained in the ring is preferably substituted with a fluorine atom.

[0065] Examples of the anion of the salt represented by formula (B2) include the following: Among these, the anions represented by formulae (B3a-1), (B3a-2), and (B3a-12) to (B3a-14) are preferred. TIFF2026042751000057.tif174165

[0066] In another embodiment of the compound (B), a salt in which the anion in the salt represented by formula (B1) is replaced with a carboxylate anion is also preferably used as the compound (B). Examples of carboxylate anions include the following: TIFF2026042751000058.tif41155

[0067] Z1 + and Z2 + As the organic cation, Z in formula (I) + Examples of the organic cations include the same as those listed above. Compound (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be combined arbitrarily. Preferred examples of acid generator (B) include a combination of an anion represented by any of formulas (B1a-1) to (B1a-4), (B1a-7) to (B1a-11), (B1a-14) to (B1a-30), (B1a-35) to (B1a-70), (B2a-1) to (B2a-11), (B2a-16) to (B2a-20), (B3a-1) to (B3a-3), or (B3a-11) to (B3a-14) with cation (b2-1), (b2-2), (b2-3), (b2-4), or (b2-5).

[0068] Preferred examples of compound (B) include those represented by formulae (B1-1) to (B1-106), (B2-1) to (B2-20), and (B3-1) to (B3-28). Among these, those containing an arylsulfonium cation are preferred, and those represented by formulae (B1-1) to (B1-3), (B1-5) to (B1-7), (B1-11) to (B1-14), (B1-20) to (B1-26), (B1-29), (B1-31) to (B1-105), (B2-1) to (B2-20), and (B3-1) to (B3-28) are particularly preferred. TIFF2026042751000059.tif176161

[0069] TIFF2026042751000060.tif254159

[0070] TIFF2026042751000061.tif250154

[0071] TIFF2026042751000062.tif252160

[0072] TIFF2026042751000063.tif252162

[0073] TIFF2026042751000064.tif250150

[0074] TIFF2026042751000065.tif186160

[0075] When the acid generator contains salt (I) and compound (B), the ratio of the 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.

[0076] [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. Examples of the resin include 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 term "acid labile group" refers to a group that has a leaving group and that is eliminated upon contact with an acid, converting the structural unit into a structural unit having a hydrophilic group (e.g., a hydroxy group or a carboxy group). The resist composition of the present invention preferably contains a quencher such as a salt that generates an acid with 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)").

[0077] <Acid generator> In the resist composition of the present invention, the content of the acid generator containing salt (I) is preferably 0.1 to 99.9% by mass, more preferably 1 to 45% by mass, even more preferably 1 to 40% by mass, and even more preferably 3 to 40% by mass, based on the solid content of the resist composition. When the resist composition contains a resin (A) described below, the total content of the acid generator containing salt (I) is preferably 1 to 45 parts by mass, more preferably 1 to 40 parts by mass, and even more preferably 3 to 40 parts by mass, based on 100 parts by mass of the resin (A) described below. When the resist composition contains compound (B) as an acid generator, the total content of salt (I) and compound (B) is preferably 0.1 to 99.9% by mass, more preferably 1 to 45% by mass, even more preferably 1 to 40% by mass, and even more preferably 3 to 40% by mass. When the resist composition contains resin (A), the total content of salt (I) and compound (B) is preferably 1 to 45 parts by mass, more preferably 1 to 40 parts by mass, and even more preferably 3 to 40 parts by mass, per 100 parts by mass of resin (A).

[0078] <Resin (A)> Resin (A) contains a structural unit having an acid labile group (hereinafter sometimes referred to as "structural unit (a1)"). Resin (A) preferably further contains a structural unit other than structural unit (a1). Examples of structural units other than structural unit (a1) include a structural unit not having an acid labile group (hereinafter sometimes referred to as "structural unit (s)") and structural units derived from other monomers known in the art.

[0079] <Structural unit (a1)> The structural unit (a1) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as "monomer (a1)"). The acid labile group contained in the resin (A) is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF2026042751000066.tif2298[In formula (1), R a1 , R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining any of these; or R a1 and R a2 are bonded to each other to form, together with the carbon atoms to which they are bonded, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * denotes a binding site.] TIFF2026042751000067.tif2278[In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’ are bonded to each other to form, together with the carbon atom to which they are bonded and X, a heterocyclic group having 3 to 20 carbon atoms, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced with -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X represents an oxygen atom or a sulfur atom. na' represents 0 or 1. * denotes a binding site.]

[0080] R a1 , R a2 and R a3 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. Ra1 , R a2 and R a3 Examples of the alkenyl group in the formula (I) include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl groups. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site): a1 , R a2 and R a3 The alicyclic hydrocarbon group preferably has 3 to 16 carbon atoms. TIFF2026042751000068.tif10159R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, or a norbornylethyl group), an aralkyl group such as a benzyl group, an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, or the like), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, or the like), and an aryl-cycloalkyl group such as a phenylcyclohexyl group. Preferably, ma is 0 and na is 1. R a1 and R a2 -C(R a1 )(R a2 )(R a3 ) includes the following groups. The alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-. TIFF2026042751000069.tif27138

[0081] R a1’ , R a2’ and R a3’ Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these groups are R a1 , R a2 and R a3 Examples of the groups include the same as those listed in the above. R a2’ and R a3’ When they are bonded to each other to form a heterocyclic group together with the carbon atoms to which they are bonded and X, -C(R a1’ )(R a2’ )-XR a3’ Examples of the groups include the following: * represents a binding site. TIFF2026042751000070.tif19124R a1’ and R a2’ At least one of these is preferably a hydrogen atom. na' is preferably 0. R a1 , R a2 , R a3 , R a1 , R a2’ and R a3’ The halogen atom that may be contained in the ring may be a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.

[0082] Examples of the group (1) include the following groups. In formula (1), R a1 , R a2 and R a3 is an alkyl group, ma=0, and na=1. The group is preferably a tert-butoxycarbonyl group. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, and R a3 is an alkyl group, ma=0, and na=1. In formula (1), R a1 and R a2 are each independently an alkyl group, and R a3 is an adamantyl group, ma=0, and na=1. Specific examples of the group (1) include the following: * represents a binding site. TIFF2026042751000071.tif149164

[0083] Specific examples of group (2) include the following groups: * represents a binding site. TIFF2026042751000072.tif55153

[0084] The monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid labile group. Of the (meth)acrylic monomers having an acid labile group, preferred are those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms. When a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in a resist composition, the resolution of the resist pattern can be improved.

[0085] Examples of structural units derived from a (meth)acrylic monomer having group (1) include a structural unit represented by formula (a1-0) (hereinafter sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter sometimes referred to as structural unit (a1-2)). Preferably, at least one structural unit selected from the group consisting of structural unit (a1-0), structural unit (a1-1), and structural unit (a1-2) is used, and more preferably at least one or two structural units selected from the group consisting of structural unit (a1-1) and structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2026042751000073.tif44144 [In formula (a1-0), formula (a1-1) and formula (a1-2), all symbols have the same meanings as defined above.]

[0086] R a01 , R a4 , R a5 The halogen atom in the formula (I) may be a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. R a01 , R a4 , R a5 Examples of the alkyl group optionally having a halogen atom in the formula (I) include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. The alkyl group is preferably a methyl group or an ethyl group, and more preferably a methyl group. R a01, R a4 and R a5 is preferably a hydrogen atom or a methyl group, more preferably a methyl group. L a01 , L a1 and L a2 is preferably an oxygen atom or —O—(CH2) k01 It is —CO—O— (wherein k01 is preferably an integer of any one of 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 , R a04 , R a6 and R a7 The alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group and combinations thereof in the formula (1) include R a1 , R a2 and R a3 Examples of the groups include the same groups as those listed in the above. R a02 , R a03 , and R a04 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a6 and R a7 The alkyl group in the formula (I) is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, an isopropyl group, or a t-butyl group, and even more preferably an ethyl group, an isopropyl group, or a t-butyl group. R a6 and R a7 The alkenyl group in the formula (I) is preferably an alkenyl group having 2 to 6 carbon atoms, and more preferably an ethenyl group, a propenyl group, an isopropenyl group, or a butenyl group. R a02 , R a03 , R a04 , R a6 and R a7 The alicyclic hydrocarbon group preferably has 5 to 12 carbon atoms, and more preferably 5 to 10 carbon atoms. R a02 , R a03 , Ra04 , R a6 and R a7 The aromatic hydrocarbon group preferably has 6 to 12 carbon atoms, and more preferably 6 to 10 carbon atoms. In the group in which an alkyl group and an alicyclic hydrocarbon group are combined, the total number of carbon atoms in the combination of the alkyl group and the alicyclic hydrocarbon group is preferably 18 or less. In the group in which an alkyl group and an aromatic hydrocarbon group are combined, the total number of carbon atoms in the combination of the alkyl group and the aromatic hydrocarbon group is preferably 18 or less. R a02 and R a03 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, ethyl group, phenyl group or naphthyl group which may have a halogen atom. R 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, ethyl group, cyclohexyl group or adamantyl group which may have a halogen atom. R a6 and R a7 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkenyl group having 2 to 6 carbon atoms which may have a halogen atom, or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, more preferably a methyl group, ethyl group, isopropyl group, t-butyl group, ethenyl group, phenyl group, or naphthyl group which may have a halogen atom, and even more preferably an ethyl group, isopropyl group, t-butyl group, ethenyl group, or phenyl group which may have a halogen atom. m1' is preferably an integer of 0 to 3, and more preferably 0 or 1. n1 is preferably an integer of 0 to 3, and more preferably 0 or 1. n1' is preferably 0 or 1.

[0087] Examples of the structural unit (a1-0) include structural units represented by any one of formulas (a1-0-1) to (a1-0-24) and R a01 and structural units in which the methyl group corresponding to the formula (a1-0-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group (an alkyl group having a halogen atom) or another alkyl group, and structural units represented by any of formulas (a1-0-1) to (a1-0-10), (a1-0-13), (a1-0-14), and (a1-0-19) to (a1-0-24) are preferred. TIFF2026042751000074.tif119160

[0088] Examples of the structural unit (a1-1) include structural units derived from monomers described in JP-A-2010-204646. Among these, structural units represented by any one of formulas (a1-1-1) to (a1-1-7) and R in the structural unit (a1-1) are preferred. a4 A structural unit in which the methyl group corresponding to the formula (a1-1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group is preferred, and a structural unit represented by any one of formulas (a1-1-1) to (a1-1-4) is more preferred. TIFF2026042751000075.tif35170

[0089] The structural unit (a1-2) includes a structural unit represented by any one of formulas (a1-2-1) to (a1-2-20) and R a5 and structural units in which the methyl group corresponding to the formula (a1-2-2), (a1-2-5), (a1-2-6), and (a1-2-10) to (a1-2-20) are substituted with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. TIFF2026042751000076.tif92164

[0090] When the resin (A) contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these structural units, based on the total structural units of the resin (A), can be 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more. Also, the total content can be 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, the total content can be 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, even more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin (A) contains the structural unit (a1-0), the content thereof, based on the total structural units of the resin (A), can be 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, even more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, and still more preferably 35 mol% or more. It can also be 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less, and still more preferably 60 mol% or less. Specifically, it can be 5 to 80 mol%, preferably 5 to 75 mol%, more preferably 10 to 70 mol%, even more preferably 10 to 65 mol%, and still more preferably 10 to 60 mol%. When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content of these units relative to the total structural units of the resin (A) can be 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, still more preferably 30 mol% or more, even more preferably 40 mol% or more, and still more preferably 50 mol% or more. Also, the total content can be 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, still more preferably 75 mol% or less, even more preferably 70 mol% or less, and still more preferably 65 mol% or less. Specifically, it can be 10 to 90 mol%, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, even more preferably 20 to 80 mol%, still more preferably 20 to 75 mol%, even more preferably 20 to 70 mol%, even more preferably 20 to 60 mol%, and still more preferably 20 to 55 mol%.

[0091] An example of the structural unit (a1) having the group (2) is a structural unit represented by formula (a1-4) (hereinafter, sometimes referred to as "structural unit (a1-4)"). TIFF2026042751000077.tif31118 [In formula (a1-4), all symbols have the same meanings as defined above.]

[0092] R a1 and R a17 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 and R a5 Examples include the same as those exemplified above. R a1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a17As the alkoxy group, alkoxyalkyl group, alkoxyalkoxy group, alkylcarbonyl group and alkylcarbonyloxy group in the above, the same groups as exemplified in this specification can be mentioned, within the range permitted by the upper limit of the number of carbon atoms. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably an alkoxy group having 1 to 3 carbon atoms, even more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably an alkoxyalkyl group having 2 to 4 carbon atoms, even more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably an alkoxyalkoxy group having 2 to 4 carbon atoms, and even more preferably a methoxyethoxy group or an ethoxyethoxy group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 4 carbon atoms, more preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and even more preferably an acetyl group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 4 carbon atoms, more preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and even more preferably an acetyloxy group. R a17 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group.

[0093] A a11Examples of the alkanediyl group include straight-chain alkyl groups such as methylene, ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, and dodecane-1,12-diyl. Examples of branched alkanediyl groups include branched alkanediyl groups such as butane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, 2-methylbutane-1,4-diyl, heptane-1,6-diyl, octane-1,7-diyl, nonane-1,8-diyl, decane-1,9-diyl, and undecane-1,10-diyl. The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, still more preferably 1 to 4, even more preferably 1 to 3, and even more preferably 1 or 2. a11 is also preferably a methylene group or an ethylene group. R a18 Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group. A a11 -CH2- in the alkanediyl group is -O-, -CO- or -NR a18 Examples of the group substituted for - include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an amino group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylamino group, a peptide group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, an alkanediylamino group, etc. These substituted groups include the same as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. For example, A a11 -CH2- in the alkanediyl group is -O-, -CO- or -NR a18Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, and *-CO-OA. a12 -CO-O-, *-O-CO-A a12 -O-, *-OA a12 -CO-O-, *-CO-OA a12 -O-CO-, *-O-CO-A a12 -O-CO-, *-CO-NR a18 Among them, *-CO-O- and *-CO-OA a12 -CO-O-, *-OA a12 -CO-O-, *-CO-NR a18 - is preferred, where 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, within the limits of the upper limit of the carbon number, a11 Examples of the alkanediyl groups include the same alkanediyl groups as those shown in the above. A a11 is a single bond, *-CO-O- or *-CO-OA a12 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. na1 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na11 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. mc is preferably 0 or 1.

[0094] R a34 , R a35 and R a36 Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which these groups are combined. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of polycyclic alicyclic hydrocarbon groups include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site): TIFF2026042751000078.tif10151 Examples of aromatic hydrocarbon groups include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group in which the above-mentioned alkyl group and alicyclic hydrocarbon group are combined (for example, an alkylcycloalkyl group or cycloalkylalkyl group such as a methylcyclohexyl group, a dimethylcyclohexyl group, a methylnorbornyl group, a cyclohexylmethyl group, an adamantylmethyl group, an adamantyldimethyl group, or a norbornylethyl group), an aralkyl group such as a benzyl group, an aromatic hydrocarbon group having an alkyl group (a p-methylphenyl group, a p-tert-butylphenyl group, a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a 2,6-diethylphenyl group, a 2-methyl-6-ethylphenyl group, or the like), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (a p-cyclohexylphenyl group, a p-adamantylphenyl group, or the like), and an aryl-cycloalkyl group such as a phenylcyclohexyl group. In particular, R a36 Examples of the group include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these groups. R a35 and R a36 Examples of the divalent heterocyclic group having 3 to 20 carbon atoms that are formed by bonding together with the -CO- to which they are bonded include the following groups: * represents a bonding site, and one of the groups is R a34 This is the binding site for TIFF2026042751000079.tif15105

[0095] 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. R a36 The hydrocarbon group in R is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. a36 The alkyl group and alicyclic hydrocarbon group in R are preferably unsubstituted. a36 The aromatic hydrocarbon group in is preferably an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0096] -OC(R a34 )(R a35 )-OR a36 is eliminated upon contact with an acid (e.g., p-toluenesulfonic acid) to form a hydroxy group or a carboxy group. -X a1 -OC(R a34 )(R a35 )-OR a36 In the case of a benzene ring, A a11 It is preferable that at least one of them is bonded to the o-position or the m-position, and more preferable that it is bonded to the p-position. In the case of a naphthalene ring, A a11 When the bonding position of A is the 1st position, it may be bonded to any of the 2nd to 8th positions. a11 When the bonding position of A is the 2nd position, it may be bonded to any of the 1st position and the 3rd to 8th positions. a11 When the bonding position of A is position 1, at least one of A is preferably bonded to position 3 to 6, and more preferably bonded to position 3 or 4. a11 When the bonding position is the 2nd position, it is preferably bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0097] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferred are structural units represented by formulas (a1-4-1) to (a1-4-42) and R in the structural unit (a1-4). a1 and more preferably, the structural units represented by formulae (a1-4-1) to (a1-4-5), (a1-4-10), (a1-4-13), (a1-4-14), (a1-4-19), and (a1-4-20). TIFF2026042751000080.tif228165

[0098] When the resin (A) contains the structural unit (a1-4), the content thereof, based on the total of all structural units in the resin (A), can be 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more. The content can also be 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, the content is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, even more preferably 20 to 85 mol%, even more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol%.

[0099] Examples of the structural unit derived from a (meth)acrylic monomer having the group (2) include a structural unit represented by formula (a1-5) (hereinafter, sometimes referred to as "structural unit (a1-5)"). TIFF2026042751000081.tif4558 [In formula (a1-5), all symbols have the same meanings as defined above.] R in formula (a1-5) a8 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 and R a5 Examples include the same as those exemplified above. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. L 51 is preferably an oxygen atom. L 52 and L 53 Among these, it is preferred that one is —O— and the other is —S—. s1 is preferably 1. s1' is preferably an integer of 0 to 2. Z a1 is preferably a single bond or —CH2—CO—O—.

[0100] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP-A-2010-61117. Among these, the structural units represented by formulas (a1-5-1) to (a1-5-4) are preferred, and the structural unit represented by formula (a1-5-1) or (a1-5-2) is more preferred. When the resin (A) contains the structural unit (a1-5), the content thereof, based on the total structural units of the resin (A), is preferably 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, even more preferably 10 mol% or more, even more preferably 20 mol% or more, and even more preferably 25 mol% or more. It may also be 80 mol% or less, preferably 70 mol% or less, more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 45 mol% or less, even more preferably 40 mol% or less, and even more preferably 30 mol% or less. Specifically, it is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, even more preferably 5 to 40 mol%, and even more preferably 5 to 30 mol%.

[0101] An example of the structural unit (a1) having the group (1) is a structural unit represented by formula (a1-6) (hereinafter, sometimes referred to as "structural unit (a1-6)"). TIFF2026042751000083.tif3479 [In formula (a1-6), all symbols have the same meanings as defined above.] R in formula (a1-6) a61 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 and R a5 Examples include the same as those exemplified above. R a61 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. R a62 , R a63 , R a64 and R a65 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group or an ethyl group. R a62 , R a63 and R a64 The cyclic hydrocarbon group in the formula (I) includes an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of polycyclic alicyclic hydrocarbon groups include a decahydronaphthyl group, an adamantyl group, and a norbornyl group. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, and more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group and a naphthylene group. Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. These groups are represented by R a17 Examples include the same as those exemplified above. R a62 and R a63 Examples of the ring formed by bonding together include an adamantane ring, a cyclopentane ring, and a cyclohexane ring. a62 and R a63 -C(R a62 )(R a63 )(R a64 ) includes the following groups. * represents the bonding site with the oxygen atom. The number of carbon atoms in the ring is preferably 3 to 16, and more preferably 3 to 12. TIFF2026042751000084.tif33109

[0102] L a61 and L a62Examples of the alkanediyl group having 1 to 4 carbon atoms in the formula include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. L a61 and L a62 are each preferably independently a methylene group or an ethylene group. X a61 is preferably a single bond or —CO—O—*, and more preferably a single bond. X a62 is preferably a single bond or *-OL a61 -, and more preferably a single bond.

[0103] Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms for Ar include a phenylene group, a 1-naphthylene group, a 2-naphthylene group, a 1-anthrylene group, a 9-anthrylene group, a biphenylene group, a 1-phenanthrylene group, and a 2-phenanthrylene group. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. These groups are preferably used in the R a17 Examples include the same as those exemplified above. Among these, the substituent is preferably a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. Ar is preferably a phenylene group which may have a substituent, and more preferably a phenylene group which may have a hydroxy group.

[0104] Examples of the structural unit (a1-6) include structural units represented by formulas (a1-6-1) to (a1-6-44), preferably structural units represented by formulas (a1-6-1) to (a1-6-9), and (a1-6-37) to (a1-6-44), more preferably structural units represented by formulas (a1-6-1), (a1-6-2), (a1-6-4), (a1-6-5), (a1-6-7), (a1-6-8), and (a1-6-37) to (a1-6-44), and even more preferably structural units represented by formulas (a1-6-7), (a1-6-8), and (a1-6-37) to (a1-6-44). a61 In the structural units shown below, the hydrogen atom corresponding to R is replaced by a methyl group or the like. a61 The structural unit (a1-6) also includes a structural unit in which the methyl group corresponding to the following is replaced with a hydrogen atom or the like. TIFF2026042751000085.tif227165

[0105] When the resin (A) contains the structural unit (a1-6), the content thereof, based on the total structural units of the resin (A), can be 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, even more preferably 10 mol% or more, still more preferably 20 mol% or more, even more preferably 30 mol% or more, and even more preferably 40 mol% or more. Also, the content can be 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, the content is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 60 mol%.

[0106] Further, examples of the structural unit (a1) include the following structural units. When resin (A) contains structural units represented by formulas (a1-7-1) to (a1-7-7), the content thereof, based on the total structural units of resin (A), can be 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more. Also, the content can be 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, it is preferably 10 to 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 %.

[0107] Further, examples of the structural unit (a1) include the following structural units. When resin (A) contains structural units represented by formulas (a1-8-1) to (a1-8-3), the content thereof, based on the total structural units of resin (A), can be 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 25 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and even more preferably 50 mol% or more. Also, the content can be 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, it is preferably 10 to 60 mol %, more preferably 15 to 55 mol %, even more preferably 20 to 50 mol %, even more preferably 20 to 45 mol %, and particularly preferably 20 to 40 mol %.

[0108] <Structural unit(s)> The structural unit (s) is derived from a monomer (hereinafter sometimes referred to as "monomer (s)") that does not have an acid labile group. As the monomer from which the structural unit (s) is derived, a monomer that does not have an acid labile group known in the resist field can be used. The structural unit (s) preferably has a hydroxy group, a carboxy group, or a lactone ring. The resist composition of the present invention may contain a resin containing a structural unit having a hydroxy group or a carboxy group but no acid labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring but no acid labile group (hereinafter sometimes referred to as "structural unit (a3)"), thereby improving the resolution of the resist pattern and adhesion to the substrate. In addition to the structural units described above, structural units (s) may also include structural units having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), structural units having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"), structural units having a sultone structure (hereinafter sometimes referred to as "structural unit (a6)"), structural units that decompose upon exposure to generate acid (hereinafter sometimes referred to as "structural unit (a7)"), and other structural units known in the art.

[0109] <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, or a carboxy group. TIFF2026042751000088.tif4095[In formula (a2), R a2 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group is -O-, -CO- or -NR a28 - may be replaced with R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. L a21 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms, and the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group is not -O-, -CO-, -S-, -SO-, or -NR a28 It may be replaced by - or -SO2-. La22 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 is not selected from -O-, -CO-, -S-, -SO-, -NR a28 It may be replaced by - or -SO2-. na2 represents an integer of 1 to 5. When na2 is 2 or more, a plurality of L a22 may be the same or different from each other. R in equation (a2) a2 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 and R a5 Examples include the same as those exemplified above. R a2 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0110] A a21 and R a28 are A in formula (a1-4), respectively. a11 and R a18 The same can be mentioned. A a21 -CH2- in the alkanediyl group is -O-, -CO- or -NR a28 Groups substituted with - include *-O-, *-CO-O-, *-O-CO-, and *-CO-OA. a22 -CO-O-, *-O-CO-A a22 -O-, *-OA a22 -CO-O-, *-CO-OA a22 -O-CO-, *-O-CO-A a22 -O-CO-, *-CO-NR a28 Among them, *-CO-O- and *-CO-OA a22 -CO-O-, *-OA a22 -CO-O-, *-CO-NR a28 - is preferred, where A a22 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents R a2A represents the bonding site with the carbon atom to which it is attached. a22 The alkanediyl group of A is, within the limits of the upper limit of the carbon number, a21 Examples of the alkanediyl groups include the same alkanediyl groups as those shown in the above. A a21 is a single bond, *-CO-O- or *-CO-OA a22 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. L a21 The hydrocarbon group in is a (na2+1)-valent hydrocarbon group, and examples thereof include linear or branched chain hydrocarbon groups, monocyclic or polycyclic (including spiro rings, fused rings, or bridged rings) alicyclic hydrocarbon groups, and cyclic hydrocarbon groups such as aromatic hydrocarbon groups, and may also be a group combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group). L a21 Examples of the chain hydrocarbon group include divalent to hexavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, an alkanpentyl group, and an alkanehexyl group. Examples of the alkanediyl group include A a21 Examples of the alkanediyl groups include the same alkanediyl groups as those shown in the above. Examples of the alkanetriyl group include a methanetriyl group, an ethanetriyl group, a propanetriyl group, a butanetriyl group, a pentanetriyl group, a hexanetriyl group, a heptanetriyl group, an octanetriyl group, a nonanetriyl group, a decantriyl group, an undecanetriyl group, a dodecanetriyl group, a tridecanetriyl group, a tetradecanetriyl group, a pentadecanetriyl group, a hexadecanetriyl group, and a heptadecanetriyl group. Examples of the alkanetetrayl group include a methanetetrayl group, an ethanetetrayl group, a propanetetrayl group, a butanetetrayl group, a pentanetetrayl group, a hexanetetrayl group, a heptanetetrayl group, an octanetetrayl group, a nonanetetrayl group, a decanetetrayl group, an undecanetetrayl group, a dodecanetetrayl group, a tridecanetetrayl group, a tetradecanetetrayl group, a pentadecanetetrayl group, a hexadecanetetrayl group, and a heptadecanetetrayl group. Examples of the alkanpentyl group include a methanepentyl group, an ethanepentyl group, a propanepentyl group, a butanepentyl group, a pentanepentyl group, and a hexanepentyl group. Examples of the alkanehexyl group include a methanehexyl group, an ethanehexyl group, a propanehexyl group, a butanehexyl group, a pentanehexyl group, and a hexanehexyl group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 10, still more preferably 1 to 9, even more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 5, and particularly preferably 1 to 4. L a21 Examples of the monocyclic and polycyclic alicyclic hydrocarbon groups in the above formula include the following alicyclic hydrocarbon groups: The binding site can be at any position. TIFF2026042751000089.tif41165 Examples include divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkanepentyl group, and a cycloalkanehexyl group. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclodecanetriyl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, and cyclodecanetetrayl group; Examples of polycyclic alicyclic hydrocarbon groups include norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, decahydronaphthalenediyl group, bicyclo[3.3.0]octanediyl group, norbornanetriyl group, adamantanetriyl group, decahydronaphthalenetriyl group, bicyclo[3.3.0]octanetriyl group, norbornanetetrayl group, adamantanetetrayl group, decahydronaphthalenetetrayl group, and bicyclo[3.3.0]octanetetrayl group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 18 carbon atoms, even more preferably 3 to 16 carbon atoms, still more preferably 3 to 12 carbon atoms, even more preferably 6 to 12 carbon atoms, and particularly preferably 6 to 10 carbon atoms. L a21 Examples of the aromatic hydrocarbon group in include divalent to hexavalent aromatic hydrocarbon groups such as an arylene group, an arenetriyl group, an arenetetrayl group, an arenetyl group, and an arenehexyl group. Specific examples include a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, a phenanthrylene group, a benzenetriyl group, a naphthalenetriyl group, an anthracenetriyl group, a biphenylenetriyl group, a phenanthrenetriyl group, a benzenetetrayl group, a naphthalenetetrayl group, an anthracenetetrayl group, a biphenylenetetrayl group, a phenanthrenetetrayl group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 20, more preferably 6 to 18, even more preferably 6 to 14, still more preferably 6 to 12, and even more preferably 6 to 10. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. Examples of the group combining two or more types include a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group, a group combining an aromatic hydrocarbon group with a chain hydrocarbon group, a group combining an alicyclic hydrocarbon group with an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group with a chain hydrocarbon group and an aromatic hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may each be combined. In addition, when any group is A a21 and L a22 may be bound to L a21 The alkanediyl group may be substituted with -O- or -CO-, etc., and L a21 When the alkanediyl group is replaced by -O- or -CO-, for example, *-L a23 -X a21 -(L a23 represents an alkanediyl group having 1 to 8 carbon atoms, and X a21 represents -O-, -O-CO-, -CO-O- or -O-CO-O-, * represents X a2 It is preferable that the bond is The -CH2- contained in the hydrocarbon group can be -O-, -S-, -SO2-, -SO-, or -NR a28Examples of groups substituted with - or -CO- include hydroxy, carboxy, thiol, alkoxy, alkylthio, alkoxycarbonyl, alkylsulfonyl, alkylcarbonyl, alkylcarbonyloxy, oxy, carbonyl, thio, sulfonyl, peptide, amino, alkylamino, alkoxycarbonyloxy, alkanediyloxy, alkanediyloxycarbonyl, alkanediylcarbonyl, alkanediylcarbonyloxy, alkanediylsulfonyl, alkanediylthio, alkanediylamino, alkanediylpeptide, cycloalkoxy, cycloalkylalkoxy, alkoxycarbonyloxy, aromatic hydrocarbon-carbonyloxy, aromatic hydrocarbon-carbonyl, aromatic hydrocarbon-oxy, and combinations of two or more of these groups. Also included are groups in which one or more hydrogen atoms of these groups have been replaced with a bonding site. These substituted groups include the same groups as those exemplified in this specification, within the limits permitted by the upper limit of the number of carbon atoms.

[0111] In addition, -CH2- contained in an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group combining these may be -O-, -S-, -CO-, -SO-, -NR a28 As the group substituted with - or -SO2-, the same groups as those exemplified in this specification can be mentioned, within the range permitted by the upper limit of the number of carbon atoms. a21 The hydrocarbon group in may have one or more substituents, such as a halogen atom, a haloalkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 16 carbon atoms (wherein —CH2— contained in the alkyl group may be replaced by —O— or —CO—), an acryloyloxy group, or a methacryloyloxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a21The hydrocarbon group in the formula (I) may have a halogen atom as a substituent, thereby substantially having a substituent such as a haloalkyl group. Examples of the haloalkyl group include alkyl fluoride, alkyl chloride, alkyl bromide, and alkyl iodide, such as a chloromethyl group, bromomethyl group, iodomethyl group, fluoromethyl group, difluoromethyl group, trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, and perfluorobutyl group. The number of carbon atoms in the haloalkyl group is preferably 1 to 8, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. L a21 The hydrocarbon group of L a21 can substantially have a substituent such as an alkyl group. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 10, even more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. L a21 The -CH2- contained in the hydrocarbon group is -O-, -S-, -CO-, -SO-, -NR a28 - or -SO2-, L a21 can substantially have a substituent such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, a thiol group, an alkylthio group, an alkylsulfonyl group, an alkoxyalkyl group, an alkoxyalkoxy group, an alkoxycarbonyloxy group, an amino group, an alkylamino group, an alkylpeptide group, an acryloyloxy group, or a methacryloyloxy group. Such groups include the same groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. L a21The substituent that the hydrocarbon group in the formula (I) may have is preferably a halogen atom, a haloalkyl group having 1 to 8 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (wherein —CH— in the alkyl group may be replaced with —O— or —CO—), more preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 10 carbon atoms (wherein —CH— in the alkyl group may be replaced with —O— or —CO—), 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 is more preferred, 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 is even more preferred, and a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, or an ethoxyethoxy group is even more preferred. Also, L a21 When the alkanediyl group is replaced by -O- or -CO-, etc., for example, *-L a23 -X a21 -(L a23 represents an alkanediyl group having 1 to 8 carbon atoms, and X a21 represents -O-, -O-CO-, -CO-O- or -O-CO-O-, * represents A a21 It is also preferred that the bond is L a21 represents a single bond, a chain hydrocarbon group having 1 to 12 carbon atoms which may have a substituent (provided that -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (provided that -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO-, -NR a28- or -SO2-) or a group formed by combining a chain hydrocarbon group of 1 to 8 carbon atoms which may have a substituent with a cyclic hydrocarbon group of 3 to 20 carbon atoms which may have a substituent (wherein -CH2- in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR a28 - or -CO-), and examples thereof include an optionally substituted chain hydrocarbon group having 1 to 10 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO-, -NR a28 - or -SO2-) or a group formed by combining a chain hydrocarbon group of 1 to 6 carbon atoms which may have a substituent with a cyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent (provided that -CH2- in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR a28 - or -CO- may be substituted.) is more preferred. L a22 Examples of the chain hydrocarbon group having 1 to 12 carbon atoms include L a21 The linear or branched alkanediyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, even more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms. L a22 may have one or more fluorine atoms. L a22 The -CH2- contained in the chain hydrocarbon group is -O-, -S-, -CO-, -SO-, -NR a28 These substituted groups may be replaced by - or -SO2-, within the range permitted by the upper limit of the carbon number. a21 Examples include the same as those exemplified above. na2 is preferably an integer of 1 to 4, and more preferably an integer of 1 to 3. L a21 When R is a single bond or a chain hydrocarbon group, examples of the structural unit (a2) include the following structural units: a2 A structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom or the like is also a suitable structural unit of the structural unit (a2), similar to the structural unit below. TIFF2026042751000090.tif67169

[0112] When producing a resist pattern from the resist composition of the present invention, if a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet) is used as an exposure light source, the structural unit (a2) preferably has a phenolic hydroxy group, and more preferably the structural unit (a2-A) described below. Furthermore, if an ArF excimer laser (193 nm) or the like is used, the structural unit (a2) preferably has an alcoholic hydroxy group, and more preferably the structural unit (a2-C) described below. The structural unit (a2) may contain one type alone or two or more types.

[0113] In the structural unit (a2), L a21 is a cyclic hydrocarbon group, and examples of the structural unit having a phenolic hydroxy group or a carboxy group include a structural unit represented by formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF2026042751000091.tif30128 [In formula (a2-A), all symbols have the same meanings as defined above.]

[0114] R in formula (a2-A) a2 , R a27 , A a21 , mc and R a28 is R in formula (a1-4) a1 , R a17 , Aa11 , mc and R a18 and similar examples are listed below. nA2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na21 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. mc is preferably 0 or 1. -X a2 -OH is a benzene ring, A a21 It is preferable that at least one of them is bonded to the m-position or p-position, and more preferable that it is bonded to the m-position. In the case of a naphthalene ring, A a21 When the bonding position of A is the 1st position, it may be bonded to any of the 2nd to 8th positions. a21 When the bonding position of A is the 2nd position, it may be bonded to any of the 1st position and the 3rd to 8th positions. a21 When the bonding position of A is position 1, at least one of A is preferably bonded to position 3 to 6, and more preferably bonded to position 3 or 4. a21 When the bonding position is the 2nd position, it is preferably bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0115] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A Nos. 2010-204634 and 2012-12577. The structural unit (a2-A) includes structural units represented by formulae (a2-2-1) to (a2-2-32), (a2-3-1) to (a2-3-24), and structural units represented by formulae (a2-2-1) to (a2-2-32), (a2-3-1) to (a2-3-24), where R in the structural unit (a2-A) a2 and a structural unit in which the methyl group corresponding to the following formula is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group. TIFF2026042751000092.tif109169

[0116] 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. It is also preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 65 mol% or less, even more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 45 mol% or less, and even more preferably 40 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, even more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%. The structural unit (a2-A) is derived from a compound represented by formula (a2-A') (hereinafter, sometimes referred to as "compound (a2-A)"). TIFF2026042751000094.tif31120 [In formula (a2-A'), the symbols have the same meanings as above.] The compound (a2-A') may be a commercially available product or may be produced by a known method. The structural unit (a2-A) can be incorporated into the resin (A) by polymerizing the compound (a2-A'). Alternatively, for example, the structural unit (a1-4) can be polymerized, followed by treatment with an acid such as p-toluenesulfonic acid, to incorporate the structural unit (a2-A). Alternatively, the structural unit (a2-A) can be polymerized using acetoxystyrene or the like, followed by treatment with an alkali such as tetramethylammonium hydroxide, to incorporate the structural unit (a2-A).

[0117] In the structural unit (a2), L a21is a cyclic hydrocarbon group, examples of the structural unit having an alcoholic hydroxy group or a carboxy group include a structural unit represented by formula (a2-B) (hereinafter may be referred to as "structural unit (a2-B)"), a structural unit represented by formula (a2-C) (hereinafter may be referred to as "structural unit (a2-C)"), and a structural unit represented by formula (a2-D) (hereinafter may be referred to as "structural unit (a2-D)"). TIFF2026042751000095.tif46100[In formula (a2-B) and formula (a2-C), R a2 has the same meaning as formula (a2). R a27 has the same meaning as formula (a2-A). L a25 is -O- or *-O-(CH2) k2 represents —CO—O—, and k2 represents an integer of 1 to 7. * represents the bonding site with —CO—. X a2 represents a single bond or -CO-. R a25 and R a26 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. nB2 represents an integer of 1 to 5. When nB2 is 2 or more, a plurality of X a2 may be the same or different from each other. nB22 represents an integer of 0 to 8. When nB22 is 2 or more, a plurality of R a27 may be the same or different from each other. nC22 represents an integer of 0 to 10. When nC22 is 2 or more, a plurality of R a27 may be the same or different from each other. L a25 is preferably —O— or —O—(CH2) f1 It is —CO—O— (wherein f1 represents an integer of 1 to 4), and more preferably —O—. R a2 is preferably a methyl group. X a2 is preferably a single bond. R a25 is preferably a hydrogen atom. R a26 is preferably a hydrogen atom or a hydroxy group. R a27 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. nB2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. nB22 is preferably an integer of 0 to 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. nC22 is preferably an integer of 0 to 6, more preferably an integer of 0 to 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1.

[0118] Examples of the structural unit (a2-B) and the structural unit (a2-C) include structural units derived from monomers described in JP-A-2010-204646, the following structural units, and R in the following structural units: a2 In particular, structural units represented by any one of formulas (a2-B-1) to (a2-B-5) and formulas (a2-C-1) to (a2-C-9) are preferred. When the resin (A) contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof, based on the total structural units of the resin (A), is 1 mol% or more, preferably 2 mol% or more. Alternatively, the content may be 45 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less, even more preferably 20 mol% or less, and even more preferably 10 mol% or less. Specifically, the content may be 1 to 45 mol%, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol%, and even more preferably 1 to 10 mol%.

[0119] TIFF2026042751000097.tif51106[In formula (a2-D), R a2 and A a21 have the same meaning as in formula (a2). R a27 has the same meaning as formula (a2-A). R a21 and R a22 each independently represents a fluorinated alkyl group having 1 to 4 carbon atoms. L a24 represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents an integer of 1 to 5. When nD2 is 2 or greater, the groups in the parentheses may be the same or different. nD22 represents an integer of 0 to 4. When nD22 is 2 or more, a plurality of R a27 may be the same or different from each other. However, 1≦nD2+nD22≦5. R a21 and R a22 Examples of the fluorinated alkyl groups are each independently a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a 3,3,3-trifluoropropyl group, a 4,4,4-trifluorobutyl group, and the like. R a21 and R a22As the aryl group, a trifluoromethyl group is preferred. L a24 Examples of the alkanediyl group include a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group. L a24 is preferably a single bond or a methylene group. R a27 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. nD2 is preferably 1, 2, 3, or 4, more preferably 1, 2, or 3, even more preferably 1 or 2, and even more preferably 1. Also preferably, nD2 is 1, and the group in parentheses is bonded to the para position. nD22 is preferably an integer of 0 to 3, more preferably an integer of 0 to 2, even more preferably 0 or 1, and even more preferably 0.

[0120] 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)"). TIFF2026042751000098.tif51107[In formula (a2-D1), R a2 , A a21 , R a27 , nD2 and nD22 have the same meaning as in formula (a2-D). In formula (a2-D1), R a2 is preferably a hydrogen atom or a methyl group. A a21 is preferably a single bond. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms, a haloalkyl 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 still more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nD22 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. nD2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2.

[0121] Examples of the structural unit (a2-D) include the structural units shown below. TIFF2026042751000099.tif62168

[0122] In the structural units represented by formulae (a2-D-1) to (a2-D-8), R a2 In the structural units represented by formulas (a2-D-9) to (a2-D-16), the hydrogen atom corresponding to R a2 Specific examples of the structural unit (a2-D) include structural units in which the methyl group corresponding to the following formula is replaced with a hydrogen atom, etc. Among these, structural units represented by formulas (a2-D-1) to (a2-D-8) are preferred, structural units represented by formulas (a2-D-1) to (a2-D-4) are more preferred, and structural units represented by formula (a2-D-1) are even more preferred.

[0123] When the resin (A) contains the structural unit (a2-D), its content is preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A). It is also preferably 80 mol% or less, more preferably 75 mol% or less, even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, even more preferably 10 to 70 mol%, and even more preferably 10 to 65 mol%.

[0124] <Structural unit (a3)> The lactone ring contained in the structural unit (a3) ​​may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or a condensed ring of a monocyclic lactone ring with another ring. Preferred examples include a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)).

[0125] The structural unit (a3) ​​is preferably a structural unit represented by formula (a3-1), formula (a3-2), formula (a3-3), or formula (a3-4). One of these may be contained alone, or two or more may be contained. TIFF2026042751000100.tif51164 [In formula (a3-1), formula (a3-2), formula (a3-3) and formula (a3-4), L a4 , L a5 and L a6 are each independently -O- or -O-(CH2) k3 It represents a group represented by —CO—O— (k3 represents an integer of 1 to 7). L a7 -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -CO-OL a9 -CO-O- or *-OL a8 -O-CO-L a9 Represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * indicates the bonding site with the carbonyl group. R a18 , R a19 , R a20 and R a24 each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 , R a23 and R a25 each independently represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents an integer of 0 to 5. q1 represents an integer of 0 to 3. r1 represents an integer of 0 to 3. w1 represents an integer of 0 to 8. When p1, q1, r1 and / or w1 are 2 or more, multiple R a21 , R a22 , R a23 and / or R a25 may be the same as or different from each other. R a21 , R a22 , R a23 and R a25 Examples of the aliphatic hydrocarbon group in include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a tert-butyl group. R a18 , R a19 , R a20 and R a24 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 , R a5Examples include the same as those exemplified above. L a8 and L a9 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. L a4 ~L a6 are each independently preferably -O- or -O-(CH2) k3 In -CO-O-, k3 is a group in which k3 is any integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and further preferably an oxygen atom. L a7 is preferably -O- or *-OL a8 It is —CO—O—, and more preferably —O—, —O—CH 2 —CO—O— or —O—C 2 H 4 —CO—O—. R a18 , R a19 , R a20 and R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a21 is preferably a methyl group. R a22 , R a23 and R a25 are each independently preferably a carboxy group, a cyano group, or a methyl group. p1, q1 and r1 each independently represent an integer of preferably 0 to 2, and more preferably 0 or 1. 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'). TIFF2026042751000101.tif2855 (in the formula, R a24 , L a7 has the same meaning as above.)

[0126] Examples of the structural unit (a3) ​​include structural units derived from monomers described in JP 2010-204646 A, JP 2000-122294 A, and JP 2012-41274 A. Examples of the structural unit (a3) ​​include structural units represented by any of formulas (a3-1-1), (a3-1-2), (a3-2-1), (a3-2-2), (a3-3-1), (a3-3-2), and (a3-4-1) to (a3-4-12), and in the structural units, R in formulas (a3-1) to (a3-4) a18 , R a19 , R a20 and R a24 A structural unit in which a methyl group corresponding to the following is replaced with a hydrogen atom is preferred. When the resin (A) contains the structural unit (a3), the total content thereof, based on all structural units in the resin (A), is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more. It may also be 70 mol% or less, preferably 65 mol% or less, more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 40 mol% or less, even more preferably 30 mol% or less, even more preferably 25 mol% or less, and even more preferably 20 mol% or less. Specifically, it may be 1 to 70 mol%, preferably 3 to 70 mol%, more preferably 3 to 65 mol%, even more preferably 5 to 65 mol%, even more preferably 5 to 60 mol%, and even more preferably 10 to 60 mol%. Furthermore, the content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3), or the structural unit (a3-4) is preferably 1 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on the total structural units of the resin (A). It is also preferably 60 mol% or less, more preferably 55 mol% or less, even more preferably 50 mol% or less, still more preferably 40 mol% or less, even more preferably 30 mol% or less, still more preferably 25 mol% or less, and even more preferably 20 mol% or less. Specifically, it is preferably 1 to 60 mol%, more preferably 3 to 60 mol%, even more preferably 3 to 55 mol%, even more preferably 5 to 55 mol%, even more preferably 5 to 50 mol%, and even more preferably 10 to 50 mol%.

[0127] <Structural unit (a4)> The structural unit represented by formula (a4) is shown below. TIFF2026042751000103.tif3553[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents an aliphatic hydrocarbon group having 1 to 48 carbon atoms and containing a halogen atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-.]

[0128] R 42 Examples of the aliphatic hydrocarbon group represented by the formula (I) include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups. Examples of the chain hydrocarbon group include linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, dodecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups, and branched alkyl groups such as isopropyl and isobutyl groups. Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include monocyclic alicyclic hydrocarbon groups which are monocyclic cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic hydrocarbon groups which are polycyclic cycloalkyl groups such as a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* indicates a bonding site): TIFF2026042751000104.tif10146 Examples of groups formed by combination include groups formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic hydrocarbon groups, such as -alkanediyl group-alicyclic hydrocarbon group, -alicyclic hydrocarbon group-alkyl group, and -alkanediyl group-alicyclic hydrocarbon group-alkyl group. Examples of the alkanediyl group include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and hexane-1,6-diyl; and branched alkanediyl groups such as propane-1,2-diyl, butane-1,3-diyl, 2-methylpropane-1,2-diyl, 1-methylbutane-1,4-diyl, and 2-methylbutane-1,4-diyl. The terminal of the branched alkanediyl group may be a methyl group. R 42 Examples of the halogen atom contained in the aliphatic hydrocarbon group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 42 Examples of the aliphatic hydrocarbon group in which -CH- is replaced with -O- or -CO- include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, a cycloalkoxy group, a cycloalkylalkoxy group, and a group combining two or more of these groups. These substituted groups include the same groups as exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms.

[0129] The structural unit (a4) is R 42 is preferably an aliphatic hydrocarbon group having a fluorine atom, and R 42 However, examples of the structural unit (a4) that is an aliphatic hydrocarbon group having a fluorine atom include a structural unit represented by formula (a4-1) (hereinafter, may be referred to as "structural unit (a4-1)"), a structural unit represented by formula (a4-2) (hereinafter, may be referred to as "structural unit (a4-2)"), a structural unit represented by formula (a4-3) (hereinafter, may be referred to as "structural unit (a4-3)"), and a structural unit represented by formula (a4-A) (hereinafter, may be referred to as "structural unit (a4-A)"). The structural unit represented by formula (a4-1) is a structural unit shown below. TIFF2026042751000105.tif3092[In formula (a4-1), R 41 represents a hydrogen atom or a methyl group. L 41 represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 42f represents a fluorine atom-containing alkanediyl group having 1 to 8 carbon atoms or a fluorine atom-containing cycloalkanediyl group having 3 to 12 carbon atoms. R 42f represents a hydrogen atom or a fluorine atom.

[0130] L 41 The alkanediyl group in R 42 Examples include those exemplified in. L 42f Examples of the alkanediyl group having a fluorine atom in the formula (I) include a linear alkanediyl group having a fluorine atom, such as a methylene group having a fluorine atom, an ethylene group having a fluorine atom, a propane-1,3-diyl group having a fluorine atom, a butane-1,4-diyl group having a fluorine atom, a pentane-1,5-diyl group having a fluorine atom, a hexane-1,6-diyl group having a fluorine atom, a heptane-1,7-diyl group having a fluorine atom, and an octane-1,8-diyl group having a fluorine atom; Examples of branched alkanediyl groups having fluorine atoms include ethane-1,1-diyl groups having fluorine atoms, propane-1,1-diyl groups having fluorine atoms, propane-1,2-diyl groups having fluorine atoms, propane-2,2-diyl groups having fluorine atoms, pentane-2,4-diyl groups having fluorine atoms, 2-methylpropane-1,3-diyl groups having fluorine atoms, 2-methylpropane-1,2-diyl groups having fluorine atoms, pentane-1,4-diyl groups having fluorine atoms, and 2-methylbutane-1,4-diyl groups having fluorine atoms. The terminal of the branched alkanediyl group may be a methyl group which may have a fluorine atom. L 42f Examples of the cycloalkanediyl group having a fluorine atom in the formula (I) include monocyclic cycloalkanediyl groups having a fluorine atom, such as a cyclobutane-1,3-diyl group having a fluorine atom, a cyclopentane-1,3-diyl group having a fluorine atom, a cyclohexane-1,4-diyl group having a fluorine atom, a cyclohexene-3,6-diyl group having a fluorine atom, a cycloheptane-1,4-diyl group having a fluorine atom, and a cyclooctane-1,5-diyl group having a fluorine atom; Examples of polycyclic cycloalkanediyl groups having a fluorine atom include a norbornane-1,4-diyl group having a fluorine atom, a norbornane-2,5-diyl group having a fluorine atom, a 5-norbornene-2,3-diyl group having a fluorine atom, an adamantane-1,5-diyl group having a fluorine atom, and an adamantane-2,6-diyl group having a fluorine atom. L 42f The number of fluorine atoms contained in the alkanediyl group and cycloalkanediyl group having a fluorine atom in the formula (I) may be 1 or more, and is preferably 2 or more. L 42f The alkanediyl group and cycloalkanediyl group having a fluorine atom in the formula (I) are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0131] L 42fExamples of the perfluoroalkanediyl group in the formula (I) include a difluoromethylene group, a perfluoroethylene group, a perfluoroethylfluoromethylene group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-2,2-diyl group, a perfluorobutane-1,4-diyl group, a perfluorobutane-2,2-diyl group, a perfluorobutane-1,2-diyl group, a perfluoropentane-1,5-diyl group, a perfluoropentane-2,2-diyl group, a perfluoropentane-3 ,3-diyl group, perfluorohexane-1,6-diyl group, perfluorohexane-2,2-diyl group, perfluorohexane-3,3-diyl group, perfluoroheptane-1,7-diyl group, perfluoroheptane-2,2-diyl group, perfluoroheptane-3,4-diyl group, perfluoroheptane-4,4-diyl group, perfluorooctane-1,8-diyl group, perfluorooctane-2,2-diyl group, perfluorooctane-3,3-diyl group, and perfluorooctane-4,4-diyl group. L 42f Examples of the perfluorocycloalkanediyl group in the formula (I) include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, and a perfluoroadamantanediyl group.

[0132] L 41 is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms, more preferably a single bond, a methylene group or an ethylene group, and even more preferably a single bond or a methylene group. L 42f is preferably a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and even more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0133] The structural unit (a4-1) includes the structural units shown below and R in the structural unit (a4-1) in the structural units shown below. 41The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026042751000106.tif55167The structural unit represented by formula (a4-2) is the structural unit shown below. TIFF2026042751000107.tif33101[In formula (a4-2), R 41 represents a hydrogen atom or a methyl group. L 43f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. R 43f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. However, L 43f and R 43f At least one of L has a fluorine atom, 43f and R 43f The maximum total number of carbon atoms is 21.

[0134] L 43f and R 43f Examples of the aliphatic hydrocarbon group in L include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups. 43f and R 43f Examples of the aliphatic hydrocarbon group in 43f and R 43f As long as the upper limit of the total number of carbon atoms in 42 Examples of the aliphatic hydrocarbon group include the same groups as the exemplified aliphatic hydrocarbon groups.

[0135] L 43f The aliphatic hydrocarbon group is preferably an alkanediyl group having 1 to 6 carbon atoms or a group represented by formula (L43f-1). TIFF2026042751000108.tif13120[In formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represents a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may contain a fluorine atom. L 47f represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may contain a fluorine atom. X 46f and X 47f each independently represents -O-, -CO-, -CO-O- or -O-CO-. However, L 45f , L 46f , L 47f , X 46f and X 47f The total number of carbon atoms is 7 or less. * and ** are binding sites, and ** is -O-CO-R 43f ]

[0136] L in the group represented by formula (L43f-1) 45f , L 46f and L 47f Examples of the divalent aliphatic hydrocarbon group represented by include a linear or branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic hydrocarbon group, and a divalent aliphatic hydrocarbon group formed by combining an alkanediyl group with a divalent alicyclic hydrocarbon group. Specific examples include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. Preferably, s is 0.

[0137] 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 TIFF2026042751000109.tif47140

[0138] R 43f is preferably an aliphatic hydrocarbon group having a fluorine atom. In this case, examples of the structural unit represented by formula (a4-2) include structural units represented by formula (a4-2A) or (a4-2B). TIFF2026042751000110.tif42157 [In formula (a4-2A) and formula (a4-2B), R 41 and L 43f represents the same as in formula (a4-2). R 43fA represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms and containing a fluorine atom. A 43f represents a divalent aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. X 43 represents **-O-CO- or **-CO-O-, and ** represents A 43f represents the binding site with R 43fB represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may contain a fluorine atom. However, in formula (a4-2A), L 43f and R 43fA The total number of carbon atoms in formula (a4-2B) is 21 or less, and in formula (a4-2B), L 43f , A 43f , X 43 and R 43fB The total number of carbon atoms in A is 21 or less. 43f and R 43fB At least one of them has at least one fluorine atom.] R 43fA The aliphatic hydrocarbon group of R 42 Examples of the aliphatic hydrocarbon groups include the same aliphatic hydrocarbon groups as those exemplified above. R 43fA is preferably an alkyl group having 1 to 13 carbon atoms and containing a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms and containing a fluorine atom, or a group combining these, and *-(CF2) n43f-R 42’ (* represents the bonding site with the carbonyl group. n43f represents an integer of 1 to 6. R 42’ represents a hydrogen atom or a fluorine atom.) or a perfluorocycloalkyl group having 3 to 12 carbon atoms is more preferred. A 43f and R 43fB The aliphatic hydrocarbon group of R in formula (a4) is as long as the upper limit of the number of carbon atoms permits. 42 Examples of the aliphatic hydrocarbon groups include the same aliphatic hydrocarbon groups as those exemplified above. A 43f is preferably a divalent chain hydrocarbon group which may have a fluorine atom, a divalent alicyclic hydrocarbon group, or a combination thereof, more preferably a divalent chain hydrocarbon group which has a fluorine atom, and even more preferably a fluorinated alkanediyl group having 1 to 6 carbon atoms. R 43fB The aliphatic hydrocarbon group which may have a fluorine atom is preferably a chain hydrocarbon group which may have a fluorine atom, an alicyclic hydrocarbon group or a group combining these, more preferably an alkyl group having 1 to 12 carbon atoms which may have a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms or a group combining these, and more preferably a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluoropropyl group, a ... More preferred are fluorinated alkyl groups such as nonafluorobutyl, butyl, perfluoropentyl, 2,2,3,3,4,4,5,5,5-nonafluoropentyl, pentyl, hexyl, perfluorohexyl, heptyl, perfluoroheptyl, octyl, and perfluorooctyl groups, cyclopropylmethyl, cyclopropyl, cyclobutylmethyl, cyclopentyl, cyclohexyl, perfluorocyclohexyl, adamantyl, adamantylmethyl, adamantyldimethyl, norbornyl, norbornylmethyl, perfluoroadamantyl, and perfluoroadamantylmethyl groups.

[0139] In formula (a4-2B), *-A 43f -X 43 -R 43fB An example of a structure that the group represented by the formula (I) can take is the following structure (* indicates the bonding site with the carbonyl group). TIFF2026042751000111.tif15170

[0140] The structural unit represented by formula (a4-2A) includes the structural units shown below and R in the structural unit represented by formula (a4-2A) in the structural units shown below. 41 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026042751000112.tif99167

[0141] The structural unit represented by formula (a4-2B) includes the structural units shown below and R in the structural unit represented by formula (a4-2B) in the structural units shown below. 41 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026042751000113.tif111163

[0142] The structural unit (a4) also includes a structural unit represented by formula (a4-3). TIFF2026042751000114.tif3589[In formula (a4-3), R 41 represents a hydrogen atom or a methyl group. L 44f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. R 44f represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may contain a fluorine atom, and -CH2- contained in the aliphatic hydrocarbon group may be replaced with -O- or -CO-. However, L 44f and R 44f At least one of L has a fluorine atom,44f and R 44f The maximum total number of carbon atoms is 21.

[0143] L 44f and R 44f Examples of the aliphatic hydrocarbon group in L include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these groups. 44f and R 44f Examples of the aliphatic hydrocarbon group in 44f and R 44f As long as the upper limit of the total number of carbon atoms in 42 Examples of the aliphatic hydrocarbon group include the same groups as the exemplified aliphatic hydrocarbon groups. L 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 - (j1 to j5 each independently represent an integer of 1 to 6). Also preferred is an alkanediyl group having 1 to 4 carbon atoms (one -CH2- contained in the alkanediyl group may be replaced with -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced with -CO-O- or -O-CO-). R 44f is preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms and having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, an alicyclic hydrocarbon group having 3 to 10 carbon atoms and having a fluorine atom, or a group combining these, further preferably an alkyl group having 1 to 10 carbon atoms and having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms and having a fluorine atom.

[0144] Examples of the structural unit represented by formula (a4-3) include the following structural units and structural units represented by the following formulas: 41 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. TIFF2026042751000115.tif85170

[0145] The structural unit (a4) also includes a structural unit represented by formula (a4-A). TIFF2026042751000116.tif3573[In formula (a4-A), R 44 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X 44 represents a single bond or *-CO-O-. * represents R 44 represents the bonding site with the carbon atom to which it is bonded. L 44 represents an aliphatic hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO- or -CO-. R 45 represents a fluorinated alkyl group having 1 to 8 carbon atoms. R 46 represents a hydrogen atom or a fluorinated alkyl group having 1 to 6 carbon atoms, and the fluorinated alkyl group is L 44 may bond to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O-. mi represents an integer of 1 to 4. When mi is 2 or more, the groups in the parentheses may be the same or different.]

[0146] R 44 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) to the formula (a1-2) include R a01 , R a4 and R a5 Examples include the same as those exemplified above. R 44 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, further preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0147] L 44 Examples of the aliphatic hydrocarbon group in include chain hydrocarbon groups and monocyclic or polycyclic (including spiro rings, fused rings, bridged rings, etc.) alicyclic hydrocarbon groups, and may also be groups that combine two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group). Examples of the chain hydrocarbon group include divalent to pentavalent chain hydrocarbon groups such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, and an alkanpentyl group. Examples of the alkanediyl group include linear alkanediyl groups such as methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, and heptadecane-1,17-diyl groups; Examples of branched alkanediyl groups include an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, even more preferably 1 to 10, still more preferably 1 to 9, even more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 5, and particularly preferably 1 to 4.

[0148] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups: The binding site can be any position. TIFF2026042751000117.tif45164 Examples include divalent to pentavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, and a cycloalkanepentyl group. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, and the like; Examples include cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, decahydronaphthalenediyl group, bicyclo[3.3.0]octanediyl group, spirocyclohexane-1,2'-cyclopentane-diyl group, and spiroadamantane-2,3'-cyclopentane-diyl group; and polycyclic alicyclic hydrocarbon groups such as spiro rings having cycloalkanediyl groups bonded to norbornanediyl groups or adamantanediyl groups via spiro bonds. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 18 carbon atoms, even more preferably 3 to 16 carbon atoms, and even more preferably 3 to 12 carbon atoms.

[0149] Examples of groups that combine two or more types include groups that combine an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, two or more types of alicyclic hydrocarbon groups and chain hydrocarbon groups may be combined. In addition, when any of the groups is X 44 may be bound to Examples of groups combining an alicyclic hydrocarbon group and a chain hydrocarbon group include a group in which an alicyclic hydrocarbon group is bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-, etc.), a group in which a chain hydrocarbon group is bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), a group in which a chain hydrocarbon group and an alicyclic hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.), Examples of such a group include a group having a hydrocarbon group bonded thereto (for example, *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-, etc.), a group having an alicyclic hydrocarbon group, a chain hydrocarbon group, and an alicyclic hydrocarbon group bonded to a chain hydrocarbon group (for example, *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-, etc.), and a group having an alicyclic hydrocarbon group, a chain hydrocarbon group, and a chain hydrocarbon group bonded to an alicyclic hydrocarbon group (for example, *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, etc.). * is X 44 represents the binding site with Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites.

[0150] L 44 -CH2- contained in the aliphatic hydrocarbon group having 1 to 28 carbon atoms may be replaced by -O-, -S-, -SO-, -SO2- or -CO-. L 44 When —CH2— contained in the aliphatic hydrocarbon group having 1 to 28 carbon atoms is replaced with —O—, —S—, —SO—, —SO2— or —CO—, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the aliphatic hydrocarbon group. Examples of groups in which -CH- in an aliphatic hydrocarbon group is replaced with -O-, -S-, -SO-, -SO-, or -CO- include a hydroxy group, a carboxy group, a thiol group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, and groups in which two or more of these groups are combined. Examples of these substituted groups include the same groups exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. Further examples include groups in which one or more hydrogen atoms of the above groups are replaced with bonding sites. Examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced by -O-, -S-, -SO-, -CO- or -SO2- include the same groups as exemplified in this specification, within the upper limit of the number of carbon atoms permitted.

[0151] L 44 The aliphatic hydrocarbon group in may have one or more substituents, such as a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms (wherein -CH2- in the alkyl group or the alicyclic hydrocarbon group may be replaced by -O- or -CO-). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of haloalkyl groups having 1 to 4 carbon atoms include fluorinated alkyl groups having 1 to 4 carbon atoms, chlorinated alkyl groups having 1 to 4 carbon atoms, brominated alkyl groups having 1 to 4 carbon atoms, and iodinated alkyl groups having 1 to 4 carbon atoms. Examples of haloalkyl groups include perfluoroalkyl groups having 1 to 4 carbon atoms (such as trifluoromethyl, pentafluoroethyl, heptafluoropropyl, and nonafluorobutyl), 2,2,2-trifluoroethyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 3,3,4,4,4-pentafluorobutyl, chloromethyl, bromomethyl, and iodomethyl. The number of carbon atoms in the haloalkyl group is preferably 1 to 3, and more preferably 1 or 2. Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, etc. The number of carbon atoms in the alkyl group is preferably 1 to 9, more preferably 1 to 6, even more preferably 1 to 4, and still more preferably 1 to 3. Examples of the alicyclic hydrocarbon group having 3 to 18 carbon atoms include monocyclic cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and cyclodecyl, and polycyclic cycloalkyl groups such as decahydronaphthyl, adamantyl, and norbornyl. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12, and even more preferably 3 to 10. Examples of aromatic hydrocarbon groups having 6 to 18 carbon atoms include a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, a binaphthyl group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 14, more preferably 6 to 12, and even more preferably 6 to 10. When -CH2- in an alkyl group is replaced with -O- or -CO-, the number of carbon atoms before the replacement is counted as the total number of carbon atoms in the alkyl group. Examples of the substituted group include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, and an alkoxycarbonyloxy group. These substituted groups include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the carbon number. The number of carbon atoms in the alkoxy group is preferably 1 to 9, more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 9, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkylcarbonyl group is preferably 2 to 10, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkylcarbonyloxy group is preferably 2 to 9, more preferably 2 to 6, even more preferably 2 to 4, and even more preferably 2 or 3. Furthermore, examples of groups in which -CH2- in an alicyclic hydrocarbon group is replaced with -O- or -CO- include the same groups as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. L 44 The substituent that the aliphatic hydrocarbon group in the formula (I) may have is preferably a halogen atom, a haloalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms (-CH2- contained in the alkyl group or the alicyclic hydrocarbon group may be replaced with -O- or -CO-), more preferably a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), and even more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group. L 44 is R 46When the fluorinated alkyl group does not form an alicyclic hydrocarbon group with the fluorinated alkyl group, the alicyclic hydrocarbon group is a chain hydrocarbon group of 1 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), or a chain hydrocarbon group of 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent. and a group formed by combining a hydrocarbon group with a hydroxyl group (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-, and -CH2- contained in the alicyclic hydrocarbon group may be replaced with -O- or -CO-), and examples thereof include a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a substituent, or a group formed by combining a hydrocarbon group with a hydroxyl group with a hydroxyl group (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-). It is more preferably a group formed by combining a chain hydrocarbon group of 1 to 6 carbon atoms with an alicyclic hydrocarbon group of 3 to 18 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and examples thereof include a chain hydrocarbon group of 1 to 8 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group of 5 to 12 carbon atoms which may have a substituent, a chain hydrocarbon group of 1 to 6 carbon atoms and More preferably, it is a group formed by combining an alicyclic hydrocarbon group of 5 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-), or a group formed by combining an alicyclic hydrocarbon group of 5 to 12 carbon atoms which may have a substituent, a chain hydrocarbon group of 1 to 6 carbon atoms, and an alicyclic hydrocarbon group of 5 to 12 carbon atoms which may have a substituent (-CH2- contained in the chain hydrocarbon group may be replaced with -O- or -CO-).

[0152] R 45Examples of the fluorinated alkyl group having 1 to 8 carbon atoms in the formula (I) include a difluoromethyl group, a trifluoromethyl group, a 1,1-difluoroethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a perfluoroethyl group, a 1,1,2,2-tetrafluoropropyl group, a 1,1,2,2,3,3-hexafluoropropyl group, a perfluoroethylmethyl group, a 1-(trifluoromethyl)-1,2,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 1,1,2,2-tetrafluorobutyl group, a 1,1,2,2,3,3-hexafluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluorobutyl group, a 1,1-bis(trifluoro)methyl group, a Examples of the fluorinated alkyl group include 2,2,2-trifluoroethyl, 2-(perfluoropropyl)ethyl, 1,1,2,2,3,3,4,4-octafluoropentyl, perfluoropentyl, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl, perfluoropentyl, 2-(perfluorobutyl)ethyl, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl, perfluoropentylmethyl, perfluorohexyl, perfluoroheptyl, and perfluorooctyl. The number of carbon atoms in the fluorinated alkyl group is preferably 1 to 6, more preferably 1 to 5, even more preferably 1 to 4, and even more preferably 1 to 3. R 46 The fluorinated alkyl group having 1 to 6 carbon atoms in R is as large as possible within the upper limit of the carbon number. 45 The same fluorinated alkyl groups having 1 to 6 carbon atoms as those given as examples of the fluorinated alkyl groups in the above can also be used. R 45 is R 46 When is a fluorinated alkyl group having 1 to 6 carbon atoms, it is preferably a fluorinated alkyl group having 1 to 6 carbon atoms, more preferably a fluorinated alkyl group having 1 to 3 carbon atoms, still more preferably a trifluoromethyl group, a perfluoroethyl group or a perfluoropropyl group, and even more preferably a trifluoromethyl group. R45 is R 46 When is a hydrogen atom, it is preferably a fluorinated alkyl group having 1 to 6 carbon atoms, more preferably a fluorinated alkyl group having 1 to 5 carbon atoms, and even more preferably a fluorinated alkyl group having 3 to 5 carbon atoms. R 46 L 44 When R is bonded to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, 46 L 44 Examples of groups formed by bonding with include groups represented by the following formulae: In the following formulae, * and ** represent bonding sites, and one of the two ** represents a bonding site with a hydroxy group and the other represents a bonding site with R 45 represents the binding site with L 44A L 44 R is a part of the hydrocarbon group and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. 46 L 44 The alicyclic hydrocarbon group formed by bonding with the above preferably has 3 to 10 carbon atoms, more preferably 3 to 8 carbon atoms, and even more preferably 3 to 6 carbon atoms. TIFF2026042751000118.tif22138R 46 is preferably a hydrogen atom or a fluorinated alkyl group having 1 to 3 carbon atoms. mi is preferably an integer of 1 to 3, more preferably 1 or 2, and even more preferably 1.

[0153] Examples of the structural unit (a4-A) include the following structural units. In the following structural units, R 44 and structural units in which the methyl group corresponding to R is replaced by a hydrogen atom, a halogen atom, a haloalkyl group, or an alkyl group other than a methyl group. 44 Specific examples of the structural unit (a4-A) include structural units in which the hydrogen atom corresponding to the following is replaced with a halogen atom, a haloalkyl group, or an alkyl group. TIFF2026042751000119.tif191165

[0154] When the resin (A) contains the structural unit (a4), the content thereof is preferably 1 to 20 mol %, more preferably 2 to 15 mol %, and even more preferably 3 to 10 mol %, based on all structural units in the resin (A).

[0155] <Structural unit (a5)> The non-leaving hydrocarbon group contained in the structural unit (a5) may be a group containing a linear, branched, or cyclic hydrocarbon group, and among these, the structural unit (a5) is preferably a group containing an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by formula (a5-1). TIFF2026042751000120.tif3971[In formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and a hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.]

[0156] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of monocyclic alicyclic hydrocarbon groups include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Examples of polycyclic alicyclic hydrocarbon groups include adamantyl and norbornyl. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, pentyl, hexyl, octyl, and 2-ethylhexyl. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. R 52is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and more preferably an adamantyl group, a norbornyl group, or a cyclohexyl group. L 55 The divalent saturated hydrocarbon group in the formula (I) includes a divalent saturated chain hydrocarbon group and a divalent saturated alicyclic hydrocarbon group, and is preferably a divalent saturated chain hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include a methylene group, an ethylene group, and an alkanediyl group such as a propanediyl group, a butanediyl group, and a pentanediyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as cyclopentanediyl and cyclohexanediyl. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include adamantanediyl and norbornanediyl. L 55 Examples of the divalent saturated hydrocarbon group represented by formula (L1-1) in which one -CH2- is replaced with -O- or -CO- include groups represented by formula (L1-1) to formula (L1-4). In the following formulae, * and ** each represent a bonding site, and * represents a bonding site to an oxygen atom. TIFF2026042751000121.tif18165[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents L x1 represents the binding site with ). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, L x1 and L x2 The total number of carbon atoms is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, L x3 and L x4 The total number of carbon atoms is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, L x5 , L x6 and L x7 The total number of carbon atoms is 15 or less. In formula (L1-4), L x8 and L x9 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, L x8 , L x9 and W x1 The total number of carbon atoms is 15 or less. L x1 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group. Examples of the group represented by formula (L1-1) include the divalent groups shown below. TIFF2026042751000122.tif36147 Examples of the group represented by formula (L1-2) include the divalent groups shown below. TIFF2026042751000123.tif23130 Examples of the group represented by formula (L1-3) include the divalent groups shown below. TIFF2026042751000124.tif16147 Examples of the group represented by formula (L1-4) include the divalent groups shown below. TIFF2026042751000125.tif13167L 55 is preferably a single bond or a group represented by formula (L1-1).

[0157] The structural unit (a5-1) includes the structural units shown below and R in the structural unit (a5-1) in the structural units shown below. 51 The structural unit in which a methyl group corresponding to the above is replaced with a hydrogen atom is an example. When the resin (A) contains the structural unit (a5), the content thereof is preferably 1 to 30 mol %, more preferably 2 to 20 mol %, and even more preferably 3 to 15 mol %, based on all structural units in the resin (A).

[0158] <Structural unit (a6)> The structural unit (a6) is a structural unit having an -SO2- group, and preferably has an -SO2- group in a side chain. The structural unit having an -SO2- group may have a linear structure having an -SO2- group, a branched structure having an -SO2- group, or a cyclic structure (monocyclic or polycyclic structure) having an -SO2- group. A structural unit having a cyclic structure having an -SO2- group is preferred, and a structural unit having a cyclic structure containing an -SO2-O- group (sultone ring) is more preferred. The sultone ring may be a ring having the following formula (T 1 -1), formula (T 1 -2), formula (T 1 -3) and the formula (T 1 The bonding site can be any position. The sultone ring may be monocyclic, but is preferably polycyclic. A polycyclic sultone ring refers to a bridged ring containing -SO2-O- as an atomic group constituting the ring, and is represented by the formula (T 1 -1) and the formula (T 1 The sultone ring is represented by the formula (T 1 As in the ring represented by formula (2), the atomic group constituting the ring may further contain a heteroatom in addition to —SO—O—. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom, and an oxygen atom is preferred. The sultone ring may have a substituent, and examples of the substituent include an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, and an alkylcarbonyl group having 2 to 4 carbon atoms. Examples of these 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. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Aralkyl groups include benzyl, phenethyl, phenylpropyl, naphthylmethyl, and naphthylethyl groups. 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.

[0159] The sultone ring is preferably a ring represented by the following formula (T1'). TIFF2026042751000128.tif2665[In formula (T1'), X 11 represents an oxygen atom, a sulfur atom or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms. ma represents an integer of 0 to 9. When ma is 2 or more, multiple R 41 may be the same or different. The binding site is at any position.] X 11 is preferably an oxygen atom or a methylene group, more preferably a methylene group. R 41 Examples of the substituent include the same as the substituent on the sultone ring, and an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group is preferred. ma is preferably 0 or 1, and more preferably 0. Examples of the ring represented by formula (T1') include the following rings: The bonding site may be any position, and the bonding site is preferably the 1st or 3rd position. The structural unit having the -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. 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.

[0160] The structural unit (a6) is preferably a structural unit represented by the formula (a6-0). TIFF2026042751000130.tif4077[In formula (a6-0), R x represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, a hydrogen atom, or a halogen atom. 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 -CH2- contained in the saturated hydrocarbon group is not -O-, -CO- or -N(R d )- may be replaced. X 11 represents an oxygen atom, a sulfur atom or a methylene group. R 41 represents the same meaning as above. 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.

[0161] Rx , R c and R d is R in formula (a1-0) to formula (a1-2) a01 , R a4 and R a5 Examples include the same as those exemplified above. 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. Specifically, methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group linear alkanediyl groups such as a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, a heptadecane-1,17-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group; branched alkanediyl groups such as butane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4-diyl, and 2-methylbutane-1,4-diyl; monocyclic divalent alicyclic saturated hydrocarbon groups such as cycloalkanediyl groups, such as cyclobutane-1,3-diyl, cyclopentane-1,3-diyl, cyclohexane-1,4-diyl, and cyclooctane-1,5-diyl; Examples include 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. A x The bonding position of to the sultone ring can be any position, but the 1-position is preferred.

[0162] Examples of the structural unit (a6-0) include the following structural units. TIFF2026042751000131.tif93150

[0163] Of these, structural units represented by formula (a6-1), formula (a6-2), formula (a6-6), formula (a6-7), formula (a6-8), and formula (a6-12) are preferred, and structural units represented by formula (a6-1), formula (a6-2), formula (a6-7), and formula (a6-8) are more preferred. When the resin (A) contains the structural unit (a6), the content thereof is preferably 1 to 50 mol %, more preferably 2 to 40 mol %, and even more preferably 3 to 30 mol %, based on all structural units in the resin (A).

[0164] <Structural unit (a7)> The resin (A) or the like may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter, sometimes referred to as "structural unit (a7)"). The structural unit (a7) functions in the resist composition in the same manner as an acid generator. Specific examples of the structural unit (a7) include structural units described in JP 2016-79235 A, and are preferably structural units having a sulfonate anion or a carboxylate anion and an organic cation in a side chain, or a structural unit having a sulfonium cation and an organic anion in a side chain. The structural unit having a sulfonate anion or a carboxylate anion and an organic cation in the side chain is preferably a structural unit represented by formula (a7-A). TIFF2026042751000132.tif26124[In formula (a7-A), R a7 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a71 is a single bond, or -O-, -CO-, -S-, -SO-, -SO2-, -NRa71 represents -, a phenylene group which may have a substituent, or a group in which these are combined. R a71 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. 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-, SO- or -SO2-. X a72 represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, and *** represents L a71 represents the binding site with na7 represents an integer of 0 to 2. When na7 is 2, the groups in the parentheses may be the same or different. RA - represents a sulfonate anion or a carboxylate anion. ZA + represents an organic cation.

[0165] R a7 is R in formula (a1-0) a01 Among them, 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, further preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. 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. X a71 represents a single bond, -O-, -CO-, -NR a71 -, a phenylene group which may have a substituent, or a group in which these are combined is preferred, and a single bond, *-O-**, *-CO-O-**, *-O-CO-O-**, *-CO-NR a71 -**, *-NR a71-CO-O-**, *-O-CO-NR a71 It is more preferable that it is -** or *-Ax-Ph-Ay-**. In the above groups, * and ** represent binding sites, * represents R a7 represents a bonding site with the carbon atom to which Ax and Ay are bonded. Ax and Ay each independently represent one or more bonding types selected from the group consisting of a single bond, an ether bond, a thioether bond, an amide bond, an ester bond, and a carbonate ester bond. Ph represents a phenylene group which may have a substituent. X a71 is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2026042751000133.tif3351[In formula (X10), Ax and Ay have the same meanings as above. 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 greater, multiple Rx's may be the same or different. When either Ax or Ay is a single bond, the other is preferably one or more bonds selected from the group consisting of an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond. When either Ax or Ay is an amide bond, -CO-NR a71 A bond represented by - is preferred. The bonding position of Ay in the phenylene group is preferably the m-position or p-position relative to the bonding position of Ax, and more preferably the p-position. Among these, Rx is preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, or an ethyl group. mx is preferably 0, 1 or 2. X a71 Examples of the group include a single bond and a group represented by the following formula (X 10 -1)~Formula(X 10 X-10)20 is -O- or -NR a71 - represents. TIFF2026042751000134.tif42162 expression (X 10 -1)~Formula(X 10 Specific examples of the group represented by -10) include the following groups: TIFF2026042751000135.tif78161Among them, X a71 is a single bond and a group of formula (X 10 -1'), expression (X 10 -3')~expression(X 10 -10'), and is preferably a single bond or a group represented by the formula (X 10 -1'), expression (X 10 -4'), expression (X 10 -5'), expression (X 10 -6') and formula (X 10 -10'), and more preferably a single bond, a group represented by the formula (X 10 -1'), a group represented by the formula (X 10 -5') or a group represented by the formula (X 10 -6') is more preferred.

[0166] L a71 The hydrocarbon group may be 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 In addition, L a72 The hydrocarbon group may be 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 following: L a71 and L a72Examples of the chain hydrocarbon group include groups 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 include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decanyl, undecanyl, dodecanyl, tridecanyl, tetradecanyl, pentane decanyl, and heptadecanyl. Examples of the alkenyl group include ethenyl, propenyl, isopropenyl, butenyl, isobutenyl, tert-butenyl, pentenyl, hexenyl, heptenyl, octenyl, isooctenyl, and nonenyl. 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 groups 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 cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. L a71 and L a72Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a bridged structure, a cycloalkyl group in which two or more rings are fused, or a cycloalkyl group in which two rings are bonded via 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 fused include a bicyclo[4.4.0]decanyl group and a steroid group (steroid skeleton). Examples of the cycloalkyl group in which two rings are bonded via a spiro bond include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group is bonded via a spiro bond to a cycloalkyl group having 5 to 8 carbon atoms. 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 alicyclic hydrocarbon groups represented by the following formula: TIFF2026042751000136.tif28158When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the alicyclic hydrocarbon group preferably has 3 to 18 carbon atoms, more preferably 3 to 12 carbon atoms, and even more preferably 3 to 8 carbon atoms.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 carbon atoms. L a71 and L a72 Examples of the aromatic hydrocarbon group include groups 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 even more preferably 6 to 10. L a71 and L a72 When -CH2- in the hydrocarbon group is replaced with -O-, -CO-, -S-, -SO- or -SO2-, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the hydrocarbon group. L a71 and L a72Among the hydrocarbon groups, examples of groups in which -CH2- in a chain hydrocarbon group is replaced with -O-, -CO-, -S-, -SO-, or -SO2- include, as described above, a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, and an alkanediylcarbonyloxy group. These substituted groups include the same as those exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. a71 and L a72 Among the hydrocarbon groups, examples of groups in which -CH2- contained in alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups combining these groups is replaced with -O-, -CO-, -S-, -SO-, or -SO2- include groups containing structures such as cyclic ethers, cyclic ketones, cyclic esters (lactone rings), cyclic thioethers, cyclic acetals, and cyclic sulfonate esters (sultone rings), as well as groups derived from furan rings or thiophene rings. These substituted groups include the same groups as exemplified in this specification, within the range permitted by the upper limit of the number of carbon atoms. a71 and L a72 Examples of the group combining two or more groups selected from the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group include a group combining the chain hydrocarbon group with the alicyclic hydrocarbon group, a group combining the chain hydrocarbon group with the aromatic hydrocarbon group, a group combining the alicyclic hydrocarbon group with the aromatic hydrocarbon group, and a group combining the chain hydrocarbon group with the alicyclic hydrocarbon group and the aromatic hydrocarbon group, and examples of the above-mentioned combined groups include the group combining the alicyclic hydrocarbon group with the aromatic hydrocarbon group. The group combining the alicyclic hydrocarbon group with the aromatic hydrocarbon group may be a fused ring. L a71 and L a72 Examples of the substituent that the hydrocarbon group may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a71 and L a72When 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 substantially 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 alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, a thiol group, an alkylthio group, or an alkylsulfonyl group. na7 is preferably 0 or 1. ZA in formula (a7-A) + The cations are the same as those in the salt represented by formula (B1).

[0167] 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, A b7 The divalent linking group may contain the same groups as those exemplified above. Examples of the structural unit represented by formula (a7-A) include a structural unit represented by formula (a7-A1). TIFF2026042751000137.tif31137[In formula (a7-A1), R a7 , X a71 , L a71 , X a72 , na7, RA - and ZA + has the same meaning as above. 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 greater, a plurality of R z71and R z72 may be the same or different from each other. Q a7 , Q b7 , R z71 and R z72 In the formula, the perfluoroalkyl group having 1 to 6 carbon atoms or the alkyl group having 1 to 6 carbon atoms is R a7 Examples of the groups include the same groups as those exemplified in the above.

[0168] Examples of the structural unit represented by formula (a7-A) include the following structural units, R a7 Examples of such a structural unit include a structural unit in which the group corresponding to the methyl group in the formula (1) 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), and the structural units described in WO 2012 / 050015. + represents an organic cation. TIFF2026042751000138.tif244163

[0169] TIFF2026042751000139.tif140161

[0170] 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). TIFF2026042751000140.tif28104[In formula (a7-B), R a7 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A b7 represents a single bond or a divalent linking group. R b71 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. R b72 and R b73 each independently represents a hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, and R b72 and R b73may be bonded to each other to form a ring together with the sulfur atom to which they are attached. A - represents an organic anion. R a7 Examples of the halogen atom and the alkyl group which may have a halogen atom include the same halogen atom and the alkyl group which may have a halogen atom as those of formula (a7-A). R b71 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by the formula include a phenylene group and a naphthylene group. R b72 and R b73 Examples of the hydrocarbon group represented by the formula (I) include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and group formed by combining these groups include the same as those described above. A b7 Examples of the divalent linking group represented by the formula (I) include divalent saturated hydrocarbon groups having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S-, or -CO-. Examples of the divalent saturated hydrocarbon group include divalent chain saturated hydrocarbon groups such as linear or branched alkanediyl groups, and monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and combinations thereof are also possible. Specific examples thereof include linear 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; and linear alkanediyl groups such as butane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-methylpropane-1,2-diyl, pentane-1,4 divalent monocyclic alicyclic saturated hydrocarbon groups such as branched alkanediyl groups, e.g., cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, and the like; and divalent polycyclic alicyclic saturated hydrocarbon groups such as polycyclic cycloalkanediyl groups, e.g., norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, and the like. Examples of saturated hydrocarbon groups in which -CH2- is replaced with -O-, -S-, or -CO- include the divalent groups shown below. 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 formula, * and ** represent bonding sites, and * represents R b71 represents the binding site with TIFF2026042751000141.tif123162[where, X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X 4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0171] The structural unit containing a cation in formula (a7-B) includes the structural unit represented by the following formula and R a7 Examples of 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 (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group). TIFF2026042751000142.tif80144

[0172] A - Examples of the organic anion represented by the formula (A) 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 anions 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).

[0173] Examples of the structural unit represented by formula (a7-B) include structural units represented by the following formulas: TIFF2026042751000143.tif95157

[0174] When the structural unit (a7) is contained in the resin (A) or the like, the content of the structural unit (a7) is preferably 1 to 20 mol %, more preferably 2 to 15 mol %, and even more preferably 3 to 10 mol %, based on all structural units in the resin (A) or the like.

[0175] 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). 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), and more preferably at least one selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). The structural unit (s) is preferably at least one selected from the group consisting of the structural unit (a2) and the structural unit (a3). The structural unit (a2) is preferably a structural unit represented by formula (a2-A) or a structural unit represented by formula (a2-C). The structural unit (a3) ​​is preferably at least one selected from the group consisting of a structural unit represented by formula (a3-1), a structural unit represented by formula (a3-2), and a structural unit represented by formula (a3-4).

[0176] The structural units constituting the resin (A) may be used singly or in combination of two or more, and can be produced by a known polymerization method (e.g., radical polymerization) using monomers that lead to these structural units. The content of each structural unit in the resin (A) can be adjusted by the amount of monomer used in the polymerization. The weight-average molecular weight of 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 it may contain oligomers with lower weight-average molecular weights. In this specification, the weight-average molecular weight is a value determined by gel permeation chromatography under the conditions described in the Examples.

[0177] <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 a resin (hereinafter sometimes referred to as "resin (AX)") that contains the same structural units as resin (A) except that it does not contain structural unit (a1), and a resin (hereinafter sometimes referred to as "resin (X)") that contains structural unit (a4) and / or structural unit (a5). Resin (AX) includes a resin containing the structural unit (a2), and preferably a resin containing the structural unit (a2-A). In resin (AX), the content of structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, based on the total of all structural units in resin (AX). Furthermore, it is preferably 80 mol% or less, more preferably 70 mol% or less. Examples of structural units that may be further contained in the resin (X) include the structural unit (a2), the structural unit (a3), and structural units derived from other known monomers. Among these, the resin (X) is preferably a resin consisting only of the structural unit (a4) and / or the structural unit (a5), and more preferably a resin consisting only of the structural unit (a4). When resin (X) contains structural unit (a4), the content of structural unit (a4) in resin (X) is, based on the total of all structural units in resin (X), 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more. Also, it may be 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it may be 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, even more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. When resin (X) contains structural unit (a5), the content of structural unit (a5) in resin (X) is, based on the total of all structural units in resin (X), 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and even more preferably 45 mol% or more. Further, it may be 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specific examples include 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%. Furthermore, 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) relative to the total of all structural units in the resin (X) 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. Specific examples include 100 mol% or less. Specific examples include 40 to 100 mol%, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and even more preferably 80 to 100 mol%. 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):the 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. The structural units constituting resins (AX) and (X) may be used singly or in combination of two or more, and can be produced by known polymerization methods (e.g., radical polymerization) using monomers that derive these structural units. The content of each structural unit in resins (AX) and (X) can be adjusted by the amount of monomer used in polymerization. The weight-average molecular weight of resin (AX) and resin (X) is preferably 6,000 or more (more preferably 7,000 or more) and 80,000 or less (more preferably 60,000 or less), but they may contain oligomers with a lower weight-average molecular weight. The weight-average molecular weight of resin (AX) and resin (X) can be measured by the same method as for resin (A).

[0178] 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).

[0179] When the resist composition of the present invention contains resin (A), the content of resin (A) is preferably from 60 to 99% by mass, more preferably from 70 to 99% by mass, even more preferably from 80 to 99% by mass, and even more preferably from 90 to 99% by mass, based on the solid content of the resist composition. Furthermore, when a resin other than resin (A) is contained, the total content of resin (A) and the resin other than resin (A) is preferably from 60 to 99% by mass, more preferably from 70 to 99% by mass, even more preferably from 80 to 99% by mass, and even more preferably from 90 to 99% by mass, based on the solid content of the resist composition. The solid content of the resist composition and the resin content relative to the solid content can be measured using known analytical methods such as liquid chromatography or gas chromatography.

[0180] <Solvent (E)> The content of the solvent (E) in the resist composition is usually from 90 to 99.9% by mass, preferably from 92 to 99% by mass, and more preferably from 94 to 99% by mass. The content of the solvent (E) can be measured by known analytical means such as liquid chromatography or gas chromatography.

[0181] 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.

[0182] <Quencher (C)> Examples of the quencher (C) include a basic nitrogen-containing organic compound and a salt that generates an acid that is weaker in acidity than the acid generated from 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 solids content of the resist composition. 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.

[0183] Examples of 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, tributaryamine, benzophenone ... ethylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldi Decylamine, 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-pyridinyl)-2-methylpropanol, 2,2 ... 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, 2,2'-methylenebisaniline, Examples thereof include 1,2-di(4-pyridyl)ethane, 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, preferably diisopropylaniline, and more preferably 2,6-diisopropylaniline. 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.

[0184] The acidity in 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. Examples of the salt that generates an acid with a lower acidity than the acid generated from the acid generator include a salt represented by the following formula, a salt 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). TIFF2026042751000144.tif95157

[0185] The weak acid inner salt (D) is preferably a diphenyliodonium salt having an iodonium cation to which two phenyl groups are bonded and a carboxylic acid anion substituted for at least one of the two phenyl groups bonded to the iodonium cation, and specifically, examples thereof include salts represented by the following formula.

[0186] TIFF2026042751000145.tif1775[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. 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 a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these groups. Examples of the chain hydrocarbon group include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, and nonyl groups. 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. Examples of aromatic hydrocarbon groups 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. Examples of 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). 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. Examples of the acyloxy group include groups in which an oxy group (—O—) is bonded to the above-mentioned acyl group. Examples of the alkoxycarbonyl group include a group in which a carbonyl group (—CO—) is bonded to the above alkoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R D1 and R D2 are 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. 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.

[0187] More specifically, the following salts are included: TIFF2026042751000146.tif72165

[0188] <Other ingredients> The resist composition of the present invention may optionally contain components other than those described above (hereinafter, these may be referred to as "other components (F)"). There are no particular limitations on the other components (F), and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, and dyes, can be used.

[0189] <Preparation of Resist Composition> The resist composition of the present invention can be prepared by mixing the salt (I), and, if necessary, the compound (B), the resin (A), 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 other factors. The mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is also not particularly limited, and stirring and mixing can be used. After mixing the components, it is preferable to filter the mixture using a filter with a pore size of about 0.003 to 0.2 μm.

[0190] <Method for producing a 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 substrate; (2) 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) A step of developing the composition layer after heating is included. The resist composition can be applied to a substrate using a commonly used device such as a spin coater. Examples of the substrate include inorganic substrates such as silicon wafers, and organic substrates having a resist film or the like formed on their surfaces. Before applying the resist composition, the substrate may be cleaned, and an anti-reflective film or the like may be formed on the substrate. The composition after coating is dried to remove the solvent and form a composition layer. Drying is carried out, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking), or by using a vacuum device. The heating temperature is preferably 50 to 200°C, and the heating time is preferably 10 to 180 seconds. The pressure during vacuum drying is preferably 1 to 1.0 x 10 5 It is preferable that the pressure is about Pa. The resulting composition layer is typically exposed using an exposure machine. The exposure machine may be an immersion exposure machine. Various exposure light sources can be used, including those that emit ultraviolet laser light such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), and F2 excimer laser (wavelength 157 nm); those that convert the wavelength of laser light from a solid-state laser source (such as a YAG or semiconductor laser) to emit harmonic laser light in the far ultraviolet or vacuum ultraviolet range; and those that irradiate with electron beams or extreme ultraviolet light (EUV). In this specification, irradiation with these types of radiation may be collectively referred to as "exposure." During exposure, exposure is typically performed through a mask corresponding to the desired pattern. When the exposure light source is an electron beam, exposure may be performed by direct writing without using a mask. The composition layer after exposure is subjected to a heat treatment (so-called post-exposure bake) to promote the deprotection reaction of the acid labile groups. The heating temperature is usually about 50 to 200°C, preferably about 70 to 150°C. A chemical treatment (silylation) may be performed to adjust the hydrophilicity or hydrophobicity of the resin on the surface side of the heated composition. Furthermore, before development, the steps of applying a resist composition, drying, exposing, and heating may be repeated on the composition layer after exposure. The heated composition layer is usually developed using a developer in a developing device. Development methods include dipping, puddling, spraying, and dynamic dispensing. The development temperature is preferably, for example, 5 to 60°C, and the development time is preferably, for example, 5 to 300 seconds. By selecting the type of developer as follows, a positive resist pattern or a negative resist pattern can be produced. When a positive resist pattern is produced from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be any of various alkaline aqueous solutions used in this field. Examples include aqueous solutions of tetramethylammonium hydroxide and (2-hydroxyethyl)trimethylammonium hydroxide (commonly known as choline). The alkaline developer may also contain a surfactant. After development, the resist pattern is preferably washed with ultrapure water, and then water remaining on the substrate and pattern is removed. When a negative resist pattern is produced from the resist composition of the present invention, a developer containing an organic solvent (hereinafter sometimes referred to as an "organic developer") is used as the developer. Examples of organic solvents contained in organic developers include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycol ether solvents such as propylene glycol monomethyl ether; amide solvents such as N,N-dimethylacetamide; and aromatic hydrocarbon solvents such as anisole. The content of the organic solvent in the organic developer is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and even more preferably substantially only the organic solvent. Among these, the organic developer is preferably a developer containing butyl acetate and / or 2-heptanone. The total content of butyl acetate and 2-heptanone in the organic developer is preferably 50% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably substantially only butyl acetate and / or 2-heptanone. The organic developer may contain a surfactant and a small amount of water. During development, development may be stopped by replacing the organic developer with a different type of solvent. The developed resist pattern is preferably washed with a rinse solution. There are no particular limitations on the rinse solution as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, preferably an alcohol solvent or an ester solvent. After cleaning, it is preferable to remove the rinse liquid remaining on the substrate and the pattern.

[0191] <Application> The resist composition of the present invention is suitable as a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, and is particularly suitable as a resist composition for electron be...

Claims

1. An acid generator containing a salt represented by formula (I): [In formula (I), Q １ , Q ２ , R １ and R ２ each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents an integer of 0 to 6, and when z is 2 or more, a plurality of R １ and R ２ may be the same or different from each other. X 1Ｚ is -O-, -CO-, -S-, -SO-, -SO ２ -, -NR ６ - or a group combining these. mm1 represents 0 or 1. L 1 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO-, -SO ２ -, -NR ６ It may be replaced by - or -CO-. L ２ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO-, -SO ２ -, -NR ６ However, L contained in the hydrocarbon group may be replaced by - or -CO-. １ -CH directly attached to the benzene ring ２ - does not replace -O-. R ６ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R ４ represents a halogen atom, a cyano group, an amino group, a nitro group, or an alkyl group having 1 to 12 carbon atoms, a hydrogen atom contained in the alkyl group may be substituted with a halogen atom, a cyano group, an amino group, or a nitro group, and —CH 2 - is -O-, -CO-, -S-, -SO-, -SO ２ -or-NR ６ It may be replaced with -. R ５ is -X １ -L １２ -R １０ , -X ２ -L １１ -X １ -L １２ -R １０ Represents. X １ and X ２ are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * represents L ２ or L １１ represents the binding site with. L １１ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ -, -SO-, -NR ６ It may be replaced by - or -CO-. L 1２ represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ -, -SO-, -NR ６ It may be replaced by - or -CO-. R １０ represents a group containing a cyclic ether structure. m4 represents an integer of 1 to 4, and when m4 is 2 or more, a plurality of R ４ may be the same or different from each other. m5 represents an integer of 1 to 4, and when m5 is 2 or greater, the groups in the parentheses may be the same or different. However, 2≦m4+m5≦5. mm2 represents an integer of 1 to 3, and when mm2 is 2 or more, the groups in the parentheses may be the same or different. Z ＋ represents an organic cation.

2. At least one L ２ -R ５ is L in the benzene ring １ 2. The acid generator according to claim 1, wherein the bond is at the o-position or p-position relative to the bonding position of

3. L 1 is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining these (however, the alkanediyl group and the cyclic hydrocarbon group may have a substituent, and the —CH 2 - is -O-, -S-, -SO ２ -, -SO-, -NR ６ 2. The acid generator according to claim 1, wherein:

4. R １０ 2. The acid generator according to claim 1, wherein the group containing a cyclic ether structure is a group represented by formula (IA), a group represented by formula (IB), or a group represented by formula (IC). [In formula (IA) and formula (IB), R Ａ represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R Ａ are either the same or different. s1 represents 1 or 2. t1 represents 0 or 1, provided that the sum of s1 and t1 is 1 or 2. L １２Ａ represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO-, -SO-, -NR ７ -or-SO ２ It may be replaced with -. L １３Ａ represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO-, -SO-, -NR ７ -or-SO ２ It may be replaced with -. R ７ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * indicates a binding site.] [In formula (IC), R Ａ represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R Ａ are either the same or different. s12 represents an integer of 0 to 2. t12 represents an integer of 0 to 2, provided that the sum of s12 and t12 is an integer of 0 to 2. L １３Ａ represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO-, -SO-, -NR ７ -or-SO ２ It may be replaced with -. R ７ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * indicates a binding site.]

5. L ２ 2. The acid generator according to claim 1, wherein is a linear alkanediyl group having 1 to 6 carbon atoms.

6. A resist composition comprising the acid generator according to any one of claims 1 to 5.

7. Further, the composition contains a resin containing a structural unit having an acid labile group, The resist composition according to claim 6, wherein the structural unit having an acid labile group comprises at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). [In formula (a1-0), formula (a1-1) and formula (a1-2), L ａ０１ , L ａ１ and L ａ２ are each independently —O— or *—O—(CH ２ ) ｋ１ represents —CO—O—, k1 represents an integer of 1 to 7, and * represents the bonding site with —CO—. R ａ０１ , R ａ４ and R ａ５ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ０２ , R ａ０３ and R ａ０４ each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may contain a halogen atom. R ａ６ and R ａ７ each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may contain a halogen atom. m1′ represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1′ represents an integer of 0 to 3. [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 —CH ２ - represents -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 a34 represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R a35 and R a36 are bonded to each other to form a divalent heterocyclic group having 3 to 20 carbon atoms together with the —C—O— to which they are bonded, 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 from each other. na11 represents an integer of 0 to 4, and when na11 is 2 or more, a plurality of R ａ１７ may be the same or different from each other. mc represents an integer of 0 to 2. [In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have one or more halogen atoms, a hydrogen atom, or a halogen atom. Z a1 is a single bond or *-(CH 2 ) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents —O— or —S—. s1 represents an integer of 1 to 3. s1′ represents an integer of 0 to 3.] [In formula (a1-6), R a61 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a6２ , R a63 and R a6４ each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a6２ and R a63 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and R a6４ 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. X a61 represents a single bond, —CO—O—*, or —CO—NR a65 - represents *, * represents the bonding site with Ar, R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 is a single bond, *-O-L a61 - or *-CO-O-L 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.]

8. 7. The resist composition according to claim 6, further comprising a resin containing a structural unit represented by formula (a2-A). [In formula (a2-A), R ａ２ represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ２７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and —CH ２ - represents -O-, -CO- or -NR ａ２８ May be replaced with -. R ａ２８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ２ represents a single bond or a carbonyl group. nA2 represents an integer of 1 to 5, and when nA2 is 2 or greater, the groups in the parentheses may be the same or different from each other. 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.

9. 7. The resist composition according to claim 6, further comprising a salt that generates an acid weaker in acidity than the acid generated from the acid generator.

10. (1) a step of applying the resist composition according to claim 6 onto a substrate; (2) drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) a step of heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising:

11. A salt represented by formula (I): [In formula (I), Q １ , Q ２ , R １ and R ２ each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms. z represents an integer of 0 to 6, and when z is 2 or more, a plurality of R １ and R ２ may be the same or different from each other. X 1Ｚ is -O-, -CO-, -S-, -SO-, -SO ２ -, -NR ６ - or a group combining these. mm1 represents 0 or 1. L 1 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO-, -SO ２ -, -NR ６ It may be replaced by - or -CO-. L ２ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO-, -SO ２ -, -NR ６ However, L contained in the hydrocarbon group may be replaced by - or -CO-. １ -CH directly attached to the benzene ring ２ - does not replace -O-. R ６ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R ４ represents a halogen atom, a cyano group, an amino group, a nitro group, or an alkyl group having 1 to 12 carbon atoms, a hydrogen atom contained in the alkyl group may be substituted with a halogen atom, a cyano group, an amino group, or a nitro group, and —CH 2 - is -O-, -CO-, -S-, -SO-, -SO ２ -or-NR ６ It may be replaced with -. R ５ is -X １ -L １２ -R １０ , -X ２ -L １１ -X １ -L １２ -R １０ Represents. X １ and X ２ are each independently *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * represents L ２ or L １１ represents the binding site with. L １１ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ -, -SO-, -NR ６ It may be replaced by - or -CO-. L 1２ represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -SO ２ -, -SO-, -NR ６ It may be replaced by - or -CO-. R １０ represents a group containing a cyclic ether structure. m4 represents an integer of 1 to 4, and when m4 is 2 or more, a plurality of R ４ may be the same or different from each other. m5 represents an integer of 1 to 4, and when m5 is 2 or greater, the groups in the parentheses may be the same or different. However, 2≦m4+m5≦5. mm2 represents an integer of 1 to 3, and when mm2 is 2 or more, the groups in the parentheses may be the same or different. Z ＋ represents an organic cation.

12. At least one L ２ -R ５ is L in the benzene ring １ The salt according to claim 11, wherein the compound is bonded at the o- or p-position relative to the bonding position of

13. L 1 is a single bond, an alkanediyl group having 1 to 6 carbon atoms, a cyclic hydrocarbon group having 3 to 18 carbon atoms, or a group formed by combining these (however, the alkanediyl group and the cyclic hydrocarbon group may have a substituent, and the —CH 2 - is -O-, -S-, -SO ２ -, -SO-, -NR ６ 13. The salt according to claim 11 or 12, wherein:

14. R １０ The salt according to claim 11 or 12, wherein the group containing a cyclic ether structure is a group represented by formula (IA), a group represented by formula (IB), or a group represented by formula (IC). [In formula (IA) and formula (IB), R Ａ represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R Ａ are either the same or different. s1 represents 1 or 2. t1 represents 0 or 1, provided that the sum of s1 and t1 is 1 or 2. L １２Ａ represents a single bond or a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO-, -SO-, -NR ７ -or-SO ２ It may be replaced with -. L １３Ａ represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO-, -SO-, -NR ７ -or-SO ２ It may be replaced with -. R ７ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * indicates a binding site.] [In formula (IC), R Ａ represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents an integer of 0 to 2, and when u1 is 2, a plurality of R Ａ are either the same or different. s12 represents an integer of 0 to 2. t12 represents an integer of 0 to 2, provided that the sum of s12 and t12 is an integer of 0 to 2. L １３Ａ represents a hydrocarbon group having 1 to 36 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO-, -SO-, -NR ７ -or-SO ２ It may be replaced with -. R ７ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. * indicates a binding site.]

15. L ２ The salt according to claim 11 or 12, wherein is a linear alkanediyl group having 1 to 6 carbon atoms.

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