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

Abstract

To provide a salt, a resist composition and the like which allow a resist pattern having good resolution to be produced.SOLUTION: An acid generator contains a salt represented by formula (I) [where R4 represents a halogen atom or a substituted / unsubstituted hydrocarbon group, and -CH2- in the group may be substituted with -O-, -CO-, -S- or -SO2-; R5 represents -X1-R10 or -X1-L10-X2-R10, X1 and X2 each represent *-CO-O-, *-O-CO-, *-O-CO-O- or the like, and L10 represents a substituted / unsubstituted hydrocarbon group; R10 represents a group represented by formula (IC); m3 represents 0 or 1, m4 represents 0-4, and m5 represents 1-4; Z+ represents an organic cation; RA represents a saturated hydrocarbon group; and u1 represents 0-2].SELECTED DRAWING: None

Description

Technical Field

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

Background Art

[0002] Patent Document 1 describes a resist composition containing a phenol salt represented by the following formula as a phenol generator. TIFF2025105523000001.tif2836

[0003] Patent Document 2 describes a resist composition containing a carboxylate represented by the following formula as a carboxylic acid generator. TIFF2025105523000002.tif2841

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention provides a salt or the like that can form a resist pattern with better resolution than a resist pattern formed by a resist composition containing the above phenol salt or carboxylate.

Means for Solving the Problems

[0006] The present invention includes the following inventions. [1] An acid generator containing a salt represented by formula (I). TIFF2025105523000003.tif25110[In formula (I), m3 represents 0 or 1. R 4 represents a halogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S-, or -SO2-. R 5 is -X 1 -R 10 or -X 1 -L 10 -X 2 -R 10 represents. X 1 and X 2 each independently represents *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * represents the bonding site to the benzene ring or L 10 ). L 10 represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. R 10 represents a group represented by formula (IC). m4 represents any integer from 0 to 4, and when m4 is 2 or more, a plurality of R 4 may be the same as or different from each other. m5 represents any integer from 1 to 4, and when m5 is 2 or more, a plurality of R 5 may be the same as or different from each other. However, 1 ≦ m4 + m5 ≦ 5. Z + represents an organic cation. TIFF2025105523000004.tif2670[In formula (IC), R A represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents any integer from 0 to 2, and when u1 is 2, a plurality of R A are the same or different. s1 represents 1 or 2. t1 represents 0 or 1. However, the sum of s1 and t1 is 1 or 2. L 12 represents a hydrocarbon group having 1 to 36 carbon atoms which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. * represents a bonding site.] [2] X 1 is the acid generator according to [1], wherein *-CO-O- or *-O-CO-. [3] The acid generator according to [1] or [2], wherein m5 is 2 or 3. [4] A resist composition containing the acid generator according to any one of [1] to [3] and an acid generator other than the acid generator. [5] The resist composition according to [4], wherein the acid generator other than the acid generator according to any one of [1] to [3] contains a salt represented by the formula (B1) or a salt represented by the formula (B3). TIFF2025105523000005.tif1396[In the formula (B1), L b1 represents a (nb1 + 1)-valent hydrocarbon group which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. L b2 represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. nb1 represents any integer from 1 to 6. When nb1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. Z1 + represents an organic cation.] TIFF2025105523000006.tif1293[In the formula (B3), A 1 represents a nitrogen atom or a carbon atom. L b2 ’ represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 ’ represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and two -SO2-L b2’ -Y b1’ may together form a ring containing A 1 thereby. nb5 represents 2 or 3. When nb5 is 2, A 1 represents a nitrogen atom, and when nb5 is 3, A 1 represents a carbon atom. The groups within multiple parentheses may be the same as or different from each other. Z2 + represents an organic cation. [6] Further, a resist composition according to [4] or [5] containing a compound having a phenolic hydroxyl group or a benzoic acid carboxy group and / or a compound in which the hydroxyl group of the phenolic hydroxyl group or the carboxy group of the benzoic acid carboxy group is protected with an acid-labile group. [7] The resist composition according to [6], wherein the compound is a resin, and the resin contains a resin containing a structural unit represented by formula (a2-A) or a structural unit represented by formula (a1-4). TIFF2025105523000007.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 a27represents a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO- or -NR a28 -. 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 any integer from 1 to 5, and when nA2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na21 represents any integer from 0 to 4, and when na21 is 2 or more, the plurality of R a27 may be the same as or different from each other. mc represents any integer from 0 to 2. TIFF2025105523000008.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 may be replaced by -O-, -CO- or -NR a18 -. 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 represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na11 represents any integer from 0 to 4. When na11 is 2 or more, the plurality of R a17 may be the same as or different from each other. mc represents any integer from 0 to 2. [8] The resist composition according to [7], wherein the resin further contains a structural unit having an acid-labile group other than the structural unit represented by the formula (a1-4), and the structural unit having an acid-labile group other than the structural unit represented by the formula (a1-4) contains at least one selected from the group consisting of the structural unit represented by the formula (a1-0), the structural unit represented by the formula (a1-1), the structural unit represented by the formula (a1-2), the structural unit represented by the formula (a1-5), and the structural unit represented by the formula (a1-6). TIFF2025105523000009.tif43144 [In the formula (a1-0), the formula (a1-1), and the formula (a1-2), L a01 L a1 and L a2 each independently represent -O- or *-O-(CH2) k1 -CO-O-, k1 represents any integer from 1 to 7, and * represents the bonding site to -CO-. R a01 R a4 and Ra5 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, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. R a6 and R a7 Each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. m1’ represents any integer from 0 to 14. n1 represents any integer from 0 to 10. n1’ represents any integer from 0 to 3. TIFF2025105523000010.tif4558[In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. Z a1 represents a single bond or *-(CH2) h3 -CO-L 54 -, h3 represents any integer from 1 to 4, and * represents the bonding site with 51 L. L 51 L 52 L 53 and L 54 Each independently represents -O- or -S-. s1 represents any integer from 1 to 3. s1’ represents any integer from 0 to 3. TIFF2025105523000011.tif3581[In formula (a1-6), Ra61 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 atom to which they are bonded. X a61 represents a single bond, -CO-O-*, or -CO-NR a65 -*, where * represents a bond to Ar, and R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 represents a single bond, *-O-L a61 -, or *-CO-O-L a62 -, where * represents a bond to Ar, and 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. [9] A step of applying the resist composition according to any one of [4] to [8] onto a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, a method for manufacturing a resist pattern including the above steps.

[10] The salt represented by the above-described formula (I).

[11] The salt according to

[10] , wherein X 1 is *-CO-O- or *-O-CO-.

[12] The salt according to

[10] or

[11] , wherein m5 is 2 or 3. [Effect of the Invention]

[0007] By using the resist composition containing the salt of the present invention, a resist pattern can be produced with good resolution.

Mode for Carrying Out the Invention

[0008] In the present specification, the “(meth)acrylic monomer” means “at least one of acrylic monomers and methacrylic monomers”. Notations such as “(meth)acrylate” and “(meth)acrylic acid” also represent the same meaning. Among the groups described in the present specification, those that can take both a linear structure and a branched structure may be either of them. When -CH2- contained in a hydrocarbon group or the like is replaced by -O-, -S-, -CO-, -SO-, -NR X -(X is an arbitrary symbol) or -SO2-, the same examples are applied to each group, and the carbon number before replacement is taken as the carbon number of the hydrocarbon group or the like. The “combined group” means a group formed by bonding two or more of the exemplified groups, and the valences of those groups may be appropriately changed depending on the bonding form. “Derived from” or “derived” means that the polymerizable C═C bond contained in the molecule becomes a -C-C- group (single bond) by polymerization. When stereoisomers exist, all stereoisomers are included. The “acid-labile group” means a group that, when contacted with an acid (for example, trifluoromethanesulfonic acid or the like), the leaving group is eliminated to form a hydrophilic group (for example, a hydroxy group or a carboxy group). The base-labile group means a group that, when contacted with a base (for example, trimethylamine, tetramethylammonium hydroxide or the like), the leaving group is eliminated to form a hydrophilic group (for example, a carboxy group or a hydroxy group). Each group may have any position and number of hydrogen atoms contained in the group replaced by a bond depending on the number of substituents and the like. The carbon number in the substituent is not included in the carbon number of the group to be substituted. In the present specification, the “solid content of the resist composition” means the total of the components excluding the solvent (E) described later from the total amount of the resist composition.

[0009] 〔Salt Represented by Formula (I)〕 The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as “salt (I)”). Among salts (I), the side with a negative charge may be referred to as "anion (I)", and the side with a positive charge may be referred to as "cation (I)". TIFF2025105523000012.tif25110[In formula (I), all symbols have the same meanings as described above respectively.]

[0010] In formula (I), R 4 Examples of the halogen atom of R include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. R 4 Examples of the hydrocarbon group having 1 to 18 carbon atoms of R include a chain hydrocarbon group such as an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. The alkyl group is a linear or branched alkyl group. For example, it includes 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, a dodecyl group, and the like. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples include groups represented below. The bonding site can be at any position. TIFF2025105523000013.tif46168Specifically, examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group, spirocyclohexane-1,2'-cyclopentane, spiroadamantane-2,3'-cyclopentane group and the like, and spiro rings having a norbornyl group or an adamantyl group and a cycloalkyl group respectively bonded thereto by spiro linkage. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and still more preferably 3 to 12. Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, biphenyl group, anthryl group, phenanthryl group, binaphthyl group and the like. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and still more preferably 6 to 10.

[0011] Examples of the group formed by combination include a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group (for example, aromatic hydrocarbon group - alkanediyl group - *, alkyl group - aromatic hydrocarbon group - *, and -CH2- contained in the alkanediyl group and the alkyl group may be replaced by -O-, -CO-, -S- or -SO2-), a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group (for example, alicyclic hydrocarbon group - alkanediyl group - *, alkyl group - alicyclic hydrocarbon group - *, and -CH2- contained in the alkanediyl group and the alkyl group may be replaced by -O-, -CO-, -S- or -SO2-), and a group formed by combining an aromatic hydrocarbon group and an alicyclic hydrocarbon group (for example, aromatic hydrocarbon group - alicyclic hydrocarbon group - *, alicyclic hydrocarbon group - aromatic hydrocarbon group - *). * represents a bonding site. Examples of the aromatic hydrocarbon group - alkanediyl group - * include aralkyl groups such as benzyl group and phenethyl group. Examples of the alkyl group - aromatic hydrocarbon group - * include tolyl group, xylyl group, cumenyl group and the like. Examples of the alicyclic hydrocarbon group-alkane diyl group-* include cycloalkylalkyl groups such as cyclohexylmethyl group, cyclohexylethyl group, 1-(adamantan-1-yl)methyl group, 1-(adamantan-1-yl)-1-methylethyl group, etc. Examples of the alkyl group-alicyclic hydrocarbon group-* include cycloalkyl groups having an alkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, 2-alkyladamantan-2-yl group, etc. Examples of the aromatic hydrocarbon group-alicyclic hydrocarbon group-* include phenylcyclohexyl group, etc. Examples of the alicyclic hydrocarbon group-aromatic hydrocarbon group-* include cyclohexylphenyl group, etc. In the combination, two or more kinds of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined respectively. Also, any of these groups may be bonded to the benzene ring.

[0012] R 4 When -CH2- contained in the hydrocarbon group represented by is replaced by -O-, -CO-, -S- or -SO2-, the carbon number before replacement is taken as the total carbon number of the haloalkyl group or the hydrocarbon group. Also, the number may be one or two or more. Examples of groups in which -CH2- contained in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkanedioxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -CO-O-), an alkanediylthio group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -S-),An alkanediylsulfonyl group (a group in which any -CH2- at an arbitrary position in the alkanediyl group is replaced by -SO2-), a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, a haloalkoxy group (a group in which any -CH2- at an arbitrary position in the haloalkyl group is replaced by -O-), a haloalkoxycarbonyl group (a group in which any -CH2-CH2- at an arbitrary position in the haloalkyl group is replaced by -O-CO-), a haloalkylcarbonyl group (a group in which any -CH2- at an arbitrary position in the haloalkyl group is replaced by -CO-), a haloalkylcarbonyloxy group (a group in which any -CH2-CH2- at an arbitrary position in the haloalkyl group is replaced by -CO-O-), a group formed by combining two or more of these groups, and the like can be mentioned. Examples of the alkoxy group include alkoxy groups having 1 to 71 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, and the like. The number of carbon atoms of the alkoxy group may be 1 to 48, preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 71 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group and the like. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 72 carbon atoms, such as acetyl group, propionyl group and butyryl group and the like. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 71 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group and the like. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 71 carbon atoms, such as butoxycarbonyloxy group and the like. The number of carbon atoms of the alkoxycarbonyl group may be 2 to 48, preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group may be 2 to 48, preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group and the alkoxycarbonyloxy group may each be 2 to 48, preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkylthio group include alkylthio groups having 1 to 17 carbon atoms, such as methylthio group, ethylthio group, propylthio group, butylthio group, pentylthio group, hexylthio group, octylthio group, 2-ethylhexylthio group, nonylthio group, decylthio group, undecylthio group and the like. The number of carbon atoms of the alkylthio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 17 carbon atoms, such as methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, butylsulfonyl group, pentylsulfonyl group, hexylsulfonyl group, octylsulfonyl group, 2-ethylhexylsulfonyl group, nonylsulfonyl group, decylsulfonyl group, undecylsulfonyl group and the like. The number of carbon atoms of the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanedioxy group include alkanedioxy groups having 1 to 17 carbon atoms, such as methyleneoxy group, ethyleneoxy group, propanedioloxy group, butanedioloxy group, pentanedioloxy group and the like. The number of carbon atoms of the alkanedioxy group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl oxycarbonyl group include alkanediyl oxycarbonyl groups having 2 to 17 carbon atoms, such as a methylene oxycarbonyl group, an ethylene oxycarbonyl group, a propanediyl oxycarbonyl group, and a butanediyl oxycarbonyl group. Examples of the alkanediyl carbonyl group include alkanediyl carbonyl groups having 2 to 18 carbon atoms, such as a methylene carbonyl group, an ethylene carbonyl group, a propanediyl carbonyl group, a butanediyl carbonyl group, and a pentanediyl carbonyl group. Examples of the alkanediyl carbonyloxy group include alkanediyl carbonyloxy groups having 2 to 17 carbon atoms, such as a methylene carbonyloxy group, an ethylene carbonyloxy group, a propanediyl carbonyloxy group, and a butanediyl carbonyloxy group. The number of carbon atoms in the alkanediyl oxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediyl carbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediyl carbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediyl thio group include alkanediyl thio groups having 1 to 17 carbon atoms, such as a methylene thio group, an ethylene thio group, and a propylene thio group. The number of carbon atoms in the alkanediyl thio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl sulfonyl group include alkanediyl sulfonyl groups having 1 to 17 carbon atoms, such as a methylene sulfonyl group, an ethylene sulfonyl group, and a propylene sulfonyl group. The number of carbon atoms in the alkanediyl sulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the cycloalkoxy group include cycloalkoxy groups having 3 to 71 carbon atoms, such as a cyclohexyloxy group. Examples of the cycloalkylalkoxy group include cycloalkylalkoxy groups having 4 to 71 carbon atoms, such as a cyclohexylmethoxy group. Examples of the aromatic hydrocarbon group-carbonyloxy group include aromatic hydrocarbon group-carbonyloxy groups having 7 to 71 carbon atoms, such as a benzoyloxy group. Examples of the aromatic hydrocarbon group-carbonyl group include aromatic hydrocarbon group-carbonyl groups having 7 to 72 carbon atoms, such as a benzoyl group. Examples of the aromatic hydrocarbon group-oxy group include aromatic hydrocarbon group-oxy groups having 6 to 72 carbon atoms, such as a phenyloxy group.

[0013] In addition, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S- or -CO- include the groups represented below. The bonding site can be at any position. TIFF2025105523000014.tif46168 Examples of the group in which -CH2- contained in the group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- also include the following groups. The bonding site can be at any position. TIFF2025105523000015.tif26164

[0014] R 4 Examples of the substituent that the hydrocarbon group of may have include a halogen atom and a cyano group. R 4 When R is a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group and an alkyl group, the alkyl group can be a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. Further, when -CH2- contained in the alkyl group contained in R is replaced by -O-, -CO-, -S- or -SO2-, R 4 4The hydrocarbon group can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, a sulfonyl group, etc. Examples of the halogen atom include the same groups as those described above. Examples of the hydrocarbon group having a halogen atom include a haloalkyl group, a haloalkoxy group, a haloalkoxycarbonyl group, a haloalkylcarbonyl group, a haloalkylcarbonyloxy group, and groups in which one or more hydrogen atoms in the alkyl group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, or alkylcarbonyloxy group exemplified above are replaced with halogen atoms. Examples of the haloalkyl group include a fluoroalkyl group, a chloroalkyl group, a bromoalkyl group, an iodoalkyl group, etc. Further, examples of the haloalkyl group include a perfluoroalkyl group (trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, etc.), 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, and 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, iodomethyl group, etc. The number of carbon atoms of the haloalkyl group is preferably 1 to 9, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. R 4 is preferably a halogen atom, an alkyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced with -O- or -CO-), or a haloalkyl group having 1 to 4 carbon atoms, more preferably an iodine atom, a fluorine atom, a hydroxy group, a carboxy group, or a fluoroalkyl group having 1 to 4 carbon atoms, still more preferably an iodine atom, a fluorine atom, a hydroxy group, a methyl group, a carboxy group, or a perfluoroalkyl group having 1 to 3 carbon atoms, and even more preferably an iodine atom, a fluorine atom, a hydroxy group, a carboxyl group, or a methyl group. m4 is preferably any integer represented by 0 to 3, and more preferably 0 or 1.

[0015] R 5 The X contained in 1 is preferably *-CO-O- or *-O-CO- (* represents the bonding site with the benzene ring).

[0016] R 5 The L contained in 10 Examples of the hydrocarbon group in include chain hydrocarbon groups such as alkanediyl groups, monocyclic or polycyclic (including spiro rings) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and groups formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and an alkanediyl group) may also be used. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-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, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. The terminal of the branched alkanediyl group may be a methyl group. The number of carbon atoms of the chain hydrocarbon group may be 1 to 24, preferably 1 to 18, more preferably 1 to 12, still more preferably 1 to 9, even more preferably 1 to 6, and even more preferably 1 to 4. TIFF2025105523000016.tif46168 Specifically, examples of the alicyclic hydrocarbon group include monocyclic divalent 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, etc., which are cycloalkanediyl groups, and polycyclic divalent alicyclic hydrocarbon groups such as spiro rings having a cycloalkyl group, norbornyl group or adamantyl group each spiro-bonded to a norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, spirocyclohexane-1,2’-cyclopentane, spiroadamantane-2,3’-cyclopentane group, etc. 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 phenylene group, naphthylene group, anthrylene group, biphenylene group, phenanthrylene group, etc., which are aromatic hydrocarbon groups. The number of carbon atoms in the aromatic hydrocarbon group may be 6 to 24, preferably 6 to 18, more preferably 6 to 14, and even more preferably 6 to 10. Examples of the group formed by combining two or more types include a group formed by combining an alicyclic hydrocarbon group and an alkanediyl group, a group formed by combining an aromatic hydrocarbon group and an alkanediyl group, and a group formed by combining an alicyclic 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 be combined respectively. Also, any group may be bonded to a carbonyl group or A 1 optionally. Examples of the group formed by combining an alicyclic hydrocarbon group and an alkanediyl group include, for example, -divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-, etc. Examples of the group formed by combining an aromatic hydrocarbon group and an alkanediyl group include, for example, -divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-, and the like. Examples of the group formed by combining an alicyclic saturated hydrocarbon group and an aromatic hydrocarbon group include -aromatic hydrocarbon group-alicyclic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-, and the like. L 10 The -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms of L may be replaced by -O-, -S-, -SO2- or -CO-. L 10 When the -CH2- contained in the hydrocarbon group having 1 to 28 carbon atoms of L is replaced by -O-, -S-, -SO2- or -CO-, the carbon number before replacement is regarded as the carbon number of the hydrocarbon group. Examples of groups in which -CH2- contained in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkoxy group (a group in which any -CH2- in an alkyl group is replaced by -O-), an alkylthio group (a group in which any -CH2- in an alkyl is replaced by -S-), an alkoxycarbonyl group (a group in which any -CH2-CH2- in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which any -CH2- in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which any -CH2-CH2- in an alkyl group is replaced by -CO-O-), an alkanediyl-oxy group (a group in which any -CH2- in an alkanediyl group is replaced by -O-), an alkanediyl-oxycarbonyl group (a group in which any -CH2-CH2- in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which any -CH2- in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which any -CH2-CH2- in an alkanediyl group is replaced by -CO-O-), an alkanediylsulfonyl group (a group in which any -CH2- in an alkanediyl group is replaced by -SO2-), an alkanediylthio group (a group in which any -CH2- in an alkanediyl group is replaced by -S-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), a cycloalkoxy group,Examples include cycloalkylalkoxy groups, alkoxycarbonyloxy groups, aromatic hydrocarbon group-carbonyl oxy groups, aromatic hydrocarbon group-carbonyl groups, aromatic hydrocarbon group-oxy groups, and groups formed by combining two or more of these groups. These substituted groups, within the range allowed by the upper limit of the number of carbon atoms, are the same as the groups exemplified by R, 4 and include the same groups as those exemplified. In addition, as for the group in which -CH2- contained in an alicyclic hydrocarbon group or a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, within the range allowed by the upper limit of the number of carbon atoms, R 4 and include the same groups as those exemplified.

[0017] L 10 Substituents that L 10 may have include a halogen atom and a cyano group. When L 10 is a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group and an alkyl group, the alkyl group can be a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. Further, when -CH2- contained in the alkyl group included in L 10 is replaced by -O-, -CO-, -S- or -SO2-, the hydrocarbon group of L can substantially have substituents such as a hydroxy group, a carboxyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, a thiol group, and a sulfonyl group. L 10 The substituent in L L 10Examples thereof include an alkanediyl group having 1 to 10 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), or a group formed by combining an alkanediyl group having 1 to 4 carbon atoms and an alicyclic hydrocarbon group having 3 to 12 carbon atoms (wherein -CH2- contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced by -O- or -CO-). It is preferably an alkanediyl group having 1 to 6 carbon atoms, more preferably a methylene group, and even more preferably a methylene group.

[0018] R 5 L contained in 10 Examples of the alkanediyl group in include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, and a hexane-1,6-diyl group; and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. L 10 is preferably an alkanediyl group having 1 to 3 carbon atoms, more preferably a methylene group.

[0019] R 5 X contained in 2 is preferably *-CO-O- (* represents the bonding site with L 10 ). R 5 R contained in 10 is a group represented by formula (IC). TIFF2025105523000017.tif2982 [In formula (IC), all symbols have the same meanings as described above.] L 12Examples of the hydrocarbon group having 1 to 36 carbon atoms include aliphatic hydrocarbon groups (chain hydrocarbon groups such as alkanediyl groups, alkenediyl groups, and alkynediyl groups, and monocyclic or polycyclic alicyclic hydrocarbon groups), aromatic hydrocarbon groups, etc., and a hydrocarbon group formed by combining two or more of these groups may also be used. L 12 In the hydrocarbon group in 12 , -CH2- may be replaced by -O-, -S-, -CO- or -SO2-. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-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, dodecane-1,12-diyl group; branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group are included. Examples of the alkenediyl group include ethenediyl group, propenediyl group, isopropenediyl group, butenediyl group, isobutenediyl group, tert-butenediyl group, pentenediyl group, hexenediyl group, heptenediyl group, octenediyl group, isooctenediyl group, nonenediyl group. Examples of the alkynediyl group include ethynediyl group, propynediyl group, isopropynediyl group, butynediyl group, isobutynediyl group, tert-butynediyl group, pentynediyl group, hexynediyl group, octynediyl group, nonynediyl group, etc. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3.

[0020] L 12When -CH2- contained in the hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2-, the number of carbon atoms before replacement is L 12 shall be the total number of carbon atoms of the hydrocarbon group. Also, the number may be one or two or more. Examples of the group in which -CH2- contained in the alkanediyl group is replaced by -O-, -S-, -CO- or -SO2- include a hydroxy group (a group in which -CH2- contained in the methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- contained in the methyl group is replaced by -S-), an alkanediyl oxy group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -O-), an alkanediyl oxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -O-CO-), an alkanediyl carbonyl group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -CO-), an alkanediyl carbonyl oxy group (a group in which -CH2-CH2- at any position contained in the alkanediyl group is replaced by -CO-O-), an alkanediyl thio group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -S-), an alkanediyl sulfonyl group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -SO2-), and the like. These replaced groups include those similar to the groups exemplified by R 4 within the range permitted by the upper limit of the number of carbon atoms. In addition, the replacement in the alkenediyl group and the alkynediyl group can include a carbon-carbon double bond or a carbon-carbon triple bond at any position in the examples of the replacement in the above-described alkanediyl group.

[0021] The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples include the groups represented below. The bonding site can be at any position. TIFF2025105523000018.tif46168Specifically, as the monocyclic alicyclic hydrocarbon group, there are monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclohexene-3,6-diyl group, cyclooctane-1,5-diyl group, etc. As the polycyclic alicyclic hydrocarbon group, there are polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, 5-norbornene-2,3-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. Examples also include spiro rings having a cycloalkyl group such as spirocyclohexane-1,2’-cyclopentane, spiroadamantane-2,3’-cyclopentane group, etc., a norbornyl group or an adamantyl group each having a cycloalkyl group spiro-bonded thereto. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. In addition, as the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, within the range allowed by the upper limit of the number of carbon atoms, there are those similar to the groups exemplified by R 4 The same groups as those exemplified above can be mentioned. Examples of the aromatic hydrocarbon group include phenylene group, naphthylene group, anthrylene group, biphenylene group, phenanthrylene group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and even more preferably 6 to 10.

[0022] Examples of the hydrocarbon group formed by combining two or more kinds of groups include a group formed by combining an alkanediyl group with an alicyclic hydrocarbon group and / or an aromatic hydrocarbon group. In the combination, two or more kinds of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined respectively. For example, -alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-aromatic hydrocarbon group-, -aromatic hydrocarbon group-alkanediyl group-, etc. are included. Any of the groups may be bonded to an oxygen atom or a carbonyl group.

[0023] L 12 Examples of the substituent of the hydrocarbon group of L 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, etc. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, etc. 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, a dodecyloxy group, etc. 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 a group in which a carbonyl group or a carbonyloxy group is bonded to the above-described alkyl group or alkoxy group. Examples of the alkoxycarbonyl group having 2 to 13 carbon atoms include a methoxycarbonyl group, an ethoxycarbonyl group, a butoxycarbonyl group and the like. Examples of the alkylcarbonyl group having 2 to 13 carbon atoms include an acetyl group, a propionyl group, a butyryl group and the like. Examples of the alkylcarbonyloxy group having 2 to 13 carbon atoms include an acetyloxy group, a propionyloxy group, a butyryloxy group and the like. L 12 The hydrocarbon group in 12 may have one substituent or a plurality of substituents.

[0024] L 12 L is preferably a single bond, an alkanediyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O-, -S-, -SO2- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-), or a group combining an alkanediyl group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the alkanediyl group and the alicyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-). More preferably, it is an alkanediyl group having 1 to 6 carbon atoms, still more preferably an alkanediyl group having 1 to 3 carbon atoms, and still more preferably a methylene group.

[0025] Preferably, s1 is 1, preferably, t1 is 1, and preferably, the sum of s1 and t1 is 2. The group represented by the formula (IC) is preferably a group represented by the following. TIFF2025105523000019.tif2396

[0026] In the group represented by the formula (IC), when u1 is 1 and R A is L 12 the group bonded to the carbon atom adjacent to L is represented by the following formula. TIFF2025105523000020.tif3144R AExamples of the saturated hydrocarbon group include chain saturated hydrocarbon groups such as alkyl groups, alicyclic saturated hydrocarbon groups, and groups formed by combining two or more of these. R A Examples of the alkyl group of A include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, octyl group, nonyl group, etc. The number of carbon atoms in the chain saturated hydrocarbon group is preferably 1 to 9, more preferably 1 to 6, and still more preferably 1 to 4. The alicyclic saturated hydrocarbon group may be monocyclic, polycyclic, or spirocyclic. Examples of the alicyclic saturated hydrocarbon group include monocyclic cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclododecyl group, etc., and polycyclic cycloalkyl groups such as norbornyl group, adamantyl group, etc. The number of carbon atoms in the alicyclic saturated hydrocarbon group is preferably 3 to 10, more preferably 3 to 8, and still more preferably 3 to 6. The combined group may be a group formed by combining one alkyl group and one alicyclic saturated hydrocarbon group as described above, or a group formed by combining two or more of either or both of them. R 5 is each independently, -O-R 10 , -CO-O-R 10 , -O-CO-O-R 10 , -O-CO-R 10 or -O-L 10 -CO-O-R 10 is preferably. m5 is preferably 2 or 3.

[0027] Examples of the anion (I) include, for example, the following anions. Among them, the anions represented by formula (Ia-1) to formula (Ia-16), formula (Ia-21) to formula (Ia-35) are preferred, and the anions represented by formula (Ia-1) to formula (Ia-16), formula (Ia-22), formula (Ia-31) to formula (Ia-35) are preferred. TIFF2025105523000021.tif253160

[0028] TIFF2025105523000022.tif108166

[0029] 〔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. Specifically, cations represented by any of formula (b2-1) to formula (b2-5) (hereinafter may be referred to as "cation (b2-1)" etc. according to the formula number) are included. TIFF2025105523000023.tif82159[In formula (b2-1) to formula (b2-5), R b4 ~R b6 each independently represents a linear 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. The hydrogen atoms contained in the linear 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. The hydrogen atoms 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. The hydrogen atoms 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 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S-, or -CO-. R b7 and R b8Each 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. m2 and n2 each independently represent any integer from 0 to 5. When m2 is 2 or more, a plurality of R b7 may be the same or different, and when n2 is 2 or more, a plurality of R b8 may be the same or different. R b9 and R b10 each independently represent a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S-, or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may be bonded to each other to form a ring including -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 represent 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. Rb13 and R b14 and R b21 and R b22 and may be bonded to each other to form a ring containing a sulfur atom together with the benzene ring to which they are bonded, and the -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 from 0 to 5. q2 and r2 each independently represent an integer from 0 to 4. u2 represents 0 or 1. When o2 is 2 or more, the plurality of R b13 are the same or different, when p2 is 2 or more, the plurality of R b14 are the same or different, when q2 is 2 or more, the plurality of R b15 are the same or different, when r2 is 2 or more, the plurality of R b16 are the same or different, when s2 is 2 or more, the plurality of R b17 are the same or different, when t2 is 2 or more, the plurality of R b18 are the same or different. u3 represents an integer from 1 to 3 and satisfies 1 ≦ u3 + q23 ≦ 5. u4 and u5 each independently represent an integer from 0 to 3 and satisfy 0 ≦ u4 + o21 ≦ 5 and 0 ≦ u5 + p22 ≦ 5. o21, p22, q23, r24, t25, and s26 each independently represent an integer from 0 to 4. When u3, u4, and u5 are each 2 or more, the groups in parentheses are each the same or different. When o21, p22, q23, r24, t25, and s26 are each 2 or more, the plurality of R b21 ~R b26 are each the same or different. When u3, u4, and u5 are each 2 or more, the groups in parentheses are each the same or different. When u2 is 0, at least one of o2, p2, q2, and r2 is 1 or more, and R b13 ~R b16 Preferably, at least one of them is a halogen atom. When u2 is 1, at least one of o2, p2, s2, t2, q2, and r2 is 1 or more, and R b13 ~R b18 Preferably, at least one of them is a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, more preferably 1. Also, when u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom.

[0030] The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, and 2-ethylhexyl group. In particular, the chain hydrocarbon group of R b9 ~R b12 Preferably has 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups. TIFF2025105523000024.tif11157In particular, the alicyclic hydrocarbon group of R b9 ~R b12 Preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.

[0031] 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 methylnorbornil group, an isobornyl group, and the like. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The alkyl fluoride group represents an alkyl group having 1 to 12 carbon atoms and having a fluorine atom, and examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, and a perfluorobutyl group. The number of carbon atoms of the alkyl fluoride group is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 4.

[0032] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples thereof include an aromatic hydrocarbon group having a chain hydrocarbon group (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 an aromatic hydrocarbon group having an alicyclic hydrocarbon group (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 the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include a p-methoxyphenyl group. 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.

[0033] 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, a dodecyloxy group, and the like. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, a butyryl group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. 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, a 2-ethylhexylcarbonyloxy group, and the like.

[0034] R b4 and R b5 The ring formed by R and R bonding to each other together with the sulfur atom to which they are bonded may be any of a monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include rings having 3 to 18 carbon atoms, preferably rings having 4 to 18 carbon atoms. Further, examples of the ring containing a sulfur atom include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings, and examples thereof include the following rings. * represents a bonding site. TIFF2025105523000025.tif24142

[0035] R b9 and R b10 The ring formed by R and R together may be any of a monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Examples of this ring include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. For example, a thiolan-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, a 1,4-oxathian-4-ium ring, and the like can be mentioned. R b11 and R b12The ring formed together with the [specific group] may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. This ring includes 3-membered rings to 12-membered rings, preferably 3-membered rings to 7-membered rings. Examples include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring, etc. R b27 ~R b29 Examples of the group containing an acid-labile group of ~R include -R c30 , -CO-O-R c30 or -L c10 -CO-O-R c30 where the group represented by (L c10 represents an alkanediyl group having 1 to 6 carbon atoms, and R c30 represents an acid-labile group.). etc. are included. R b27 ~R b29 Examples of the acid-labile group of ~R include the groups (1) and / or (2) described later.

[0036] Among cations (b2-1) to (b2-5), preferably, they are cation (b2-1), cation (b2-4) or cation (b2-5). Examples of cation (b2-1) include the following cations. TIFF2025105523000026.tif149164 Examples of cation (b2-2) include the following cations. TIFF2025105523000027.tif14136 Examples of cation (b2-3) include the following cations. TIFF2025105523000028.tif21129 Examples of cation (b2-4) include the following cations. TIFF2025105523000029.tif123163 Examples of cation (b2-5) include the following cations. TIFF2025105523000030.tif115157

[0037] Salt (I) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. As the salt (I), preferably, an anion represented by any of formula (Ia-1) to formula (Ia-12), formula (Ia-21) to formula (Ia-35), and a combination with cation (b2-1), cation (b2-2), cation (b2-3), cation (b2-4) or cation (b2-5) can be mentioned. Specific examples of salt (I) are shown in the following table. In the following table, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation, and "~" indicates that each of salt (I) and anion (I) corresponds. For example, salt (I-1) is a salt composed of an anion represented by formula (Ia-1) and a cation represented by formula (b2-c-1), salt (I-2) is a salt composed of an anion represented by formula (Ia-2) and a cation represented by formula (b2-c-1), and salt (I-31) is a salt composed of an anion represented by formula (Ia-1) and a cation represented by formula (b2-c-10). TIFF2025105523000031.tif5164

Table 1

[0038] Among them, as the salt (I), a salt in which an anion represented by any of formula (Ia-1) to formula (Ia-12), formula (Ia-21) to formula (Ia-35) and a cation represented by any of formula (b2-c-1), formula (b2-c-10), formula (b2-c-13), formula (b2-c-14), formula (b2-c-18) to formula (b2-c-20), formula (b2-c-27), formula (b2-c-30), formula (b2-c-31), formula (b2-c-50) to formula (b2-c-79) are combined is preferable.

[0039] <Method for producing salt (I)> The salt (I) can be produced, for example, by reacting a salt represented by the formula (I-a) with a compound represented by the formula (I-b1) or a compound represented by the formula (I-b2) in a solvent in the presence of a catalyst. TIFF2025105523000034.tif35163(In the formula, all the symbols have the same meanings as described above. n5 represents an integer of 0 to 4.) Examples of the catalyst include potassium carbonate, potassium iodide, pyridine, diethylaminopyridine, triethylamine, carbonyldiimidazole and the like. Examples of the solvent include chloroform, monochlorobenzene, dimethylformamide, acetonitrile, ethyl acetate, water and the like. The reaction temperature is usually from 15°C to 80°C, and the reaction time is usually from 0.5 to 24 hours.

[0040] Examples of the salt represented by the formula (I-a) include salts represented below, which can be easily obtained from the market and can also be easily produced by known production methods. TIFF2025105523000035.tif152162

[0041] Examples of the compound represented by the formula (I-b1) include compounds represented below, which can be easily obtained from the market and can also be easily produced by known production methods. TIFF2025105523000036.tif17165 The compound represented by the formula (I-b2) includes, for example, compounds represented below, which can be easily obtained from the market and can also be easily produced by known production methods. TIFF2025105523000037.tif17166

[0042] 〔Acid generator〕 The acid generator of the present invention is an acid generator containing salt (I). Salt (I) of the present invention can act as a quencher in the resist composition. When using salt (I) as a quencher in the resist composition, the acid generator may contain only one kind or two or more kinds of salt (I). The acid generator of the present invention may contain salts known in the resist field other than salt (I). In this case, the ratio (mass ratio) of the content of the salt other than salt (I) to the salt is usually 1:99 to 100:0, preferably 1:99 to 99:1, more preferably 2:98 to 98:2, and still more preferably 5:95 to 95:5.

[0043] 〔Resist composition〕 The resist composition of the present invention contains an acid generator containing salt (I) of the present invention and an acid generator other than the acid generator (hereinafter sometimes referred to as "acid generator (B)"). The acid generator (B) may be used alone or in combination of two or more. The resist composition of the present invention may contain a compound having a phenolic hydroxyl group or a benzoic acid carboxyl group and / or a compound in which the hydroxyl group of the phenolic hydroxyl group or the carboxyl group of the benzoic acid carboxyl group is protected by an acid-labile group (hereinafter sometimes referred to as "phenolic hydroxyl group-containing compound etc. (L)" or "compound (L)"). The phenolic hydroxyl group-containing compound etc. (L) may be in any form such as a low molecular weight compound, an oligomer, a resin, etc. The resist composition preferably further contains a quencher (hereinafter sometimes referred to as "quencher (C)") and / or a solvent (hereinafter sometimes referred to as "solvent (E)"). In the resist composition of the present invention, the content rate of salt (I) is preferably 0.1% by mass or more and 35% by mass or less, more preferably 0.5% by mass or more and 30% by mass or less, and still more preferably 1% by mass or more and 25% by mass or less with respect to the solid content of the resist composition.

[0044] <Acid generator (B)> In the resist composition of the present invention, the total content of the acid generator (B) is preferably 0.1% by mass or more and 99.9% by mass or less, more preferably 1% by mass or more and 45% by mass or less, still more preferably 1% by mass or more and 40% by mass or less, and even more preferably 3% by mass or more and 40% by mass or less, based on the solid content of the resist composition. When the resin (A) described later is included, the total content of the acid generator (B) is preferably 1 part by mass or more (more preferably 3 parts by mass or more) and preferably 55 parts by mass or less (more preferably 50 parts by mass or less, even more preferably 45 parts by mass or less) with respect to 100 parts by mass of the resin (A).

[0045] As the acid generator (B), either a nonionic compound or an ionic compound may be used. Examples of the nonionic compound include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxy ketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), and the like. Representative examples of the ionic compound include onium salts containing an onium cation (e.g., diazonium salt, phosphonium salt, sulfonium salt, iodonium salt). Examples of the anion of the onium salt include sulfonic acid anion, sulfonylimide anion, sulfonylmethide anion, and carboxylic acid anion. Further, the acid generator (B) may be one of the structural units constituting the resin contained in the resist composition of the present invention, such as the structural unit (a7) described above.

[0046] As the acid generator (B), compounds that generate an acid upon irradiation with radiation described in, for example, 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. Patent No. 3,779,778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc. can be used. Further, compounds produced by known methods may also be used. The acid generator (B) may be an acid generator having an acid-labile group. For example, the compound or resin serving as the acid generator may contain a partial structure that becomes an acid-labile group, and the acid-labile group preferably contains the group (1) or group (2) described below. When the resist composition of the present invention has a compound having an acid-labile group, a resin containing a structural unit having an acid-labile group may not be included.

[0047] As a preferred form of the acid generator (B), salts represented by formula (B1) (hereinafter sometimes referred to as "acid generator (B1)") and salts represented by formula (B3) (hereinafter sometimes referred to as "acid generator (B3)") can be mentioned. TIFF2025105523000038.tif1391[In formula (B1), all symbols have the same meanings as described above respectively.]

[0048] L b1 As the (nb1 + 1)-valent hydrocarbon group of L, from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining two or more of these groups, nb1 hydrogen atoms are removed, and a group bonding to one or more Ls can be mentioned. b2 is mentioned. The number of carbon atoms of the hydrocarbon group is preferably 1 to 48, more preferably 1 to 42, still more preferably 1 to 36, even more preferably 1 to 30, and even more preferably 1 to 24. Examples of the chain hydrocarbon group include a group formed by removing nb1 hydrogen atoms from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples include methyl group, ethyl group, propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decanyl group, undecanyl group, dodecanyl group, tridecanyl group, tetradecanyl group, pentadecanyl group, heptadecanyl group, and the like. Examples of the alkenyl group include ethenyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, isooctenyl group, and nonenyl group. The number of carbon atoms in the chain hydrocarbon group is preferably from 1 to 36, more preferably from 1 to 24, still more preferably from 1 to 20, even more preferably from 1 to 18, still even more preferably from 1 to 12, and even more preferably from 1 to 10. Examples of the alicyclic hydrocarbon group include a group formed by removing nb1 hydrogen atoms from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include cyclobutyl group, cyclopentane group, cyclohexane group, cyclopentyl group, cyclooctyl group, and the like. Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include norbornyl group, adamantanyl group, and the like. Examples of the cycloalkyl group in which two or more rings are condensed include bicyclo[4.4.0]decanyl group, steroid group (steroid skeleton), and the like. Examples of the ring in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of cyclopentyl group, cyclohexyl group, norbornyl group, and adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. 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 those represented by the following formula. TIFF2025105523000039.tif26168 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 24, more preferably 3 to 20, still more preferably 3 to 18, even more preferably 3 to 12, even still more preferably 3 to 10, and even more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 6 to 24, more preferably 6 to 20, still more preferably 6 to 18, even more preferably 6 to 12, and even still more preferably 7 to 12. Examples of the aromatic hydrocarbon group include a group in which nb1 hydrogen atoms of an aryl group are removed. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a fluorenyl group, and the like. More specifically, examples of the aromatic hydrocarbon group include those represented by the following formula. TIFF2025105523000040.tif1185 The number of carbon atoms in the aromatic hydrocarbon group is preferably 4 to 24, more preferably 4 to 20, still more preferably 4 to 18, even more preferably 5 to 14, even still more preferably 5 to 10, and even more preferably 6 to 10. L b1 When -CH2- contained in the hydrocarbon group of L is replaced by -O-, -CO-, -S- or -SO2-, the number of carbon atoms before replacement is taken as the number of carbon atoms of the hydrocarbon group. L b1Among the hydrocarbon groups, examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a hydroxy group (a group in which -CH2- contained in the methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- contained in the methylene group is replaced by -CO-), an oxy group (a group in which -CH2- contained in the methylene group is replaced by -O-), a thiol group (a group in which -CH2- contained in the methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in the methylene group is replaced by -SO2-), an alkoxy group (a group in which -CH2- at any position contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -CO-O-), an alkylthio group (a group in which -CH2- at any position contained in the alkyl group is replaced by -S-), an alkylsulfonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -SO2-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in the alkyl group is replaced by -O-CO-O-), an alkanedioxy group (a group in which -CH2- at any position contained in the alkanedioyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkanedioyl group is replaced by -O-CO-), an alkanedioylcarbonyl group (a group in which -CH2- at any position contained in the alkanedioyl group is replaced by -CO-), an alkanedioylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkanedioyl group is replaced by -CO-O-), an alkanediylthio group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -S-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in the alkanediyl group is-SO2- and the like. These substituted groups include those similar to the groups exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms. L b1 Among the hydrocarbon groups of, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include cyclic ethers, cyclic ketones, cyclic esters (lactones), cyclic thioethers, cyclic acetals, cyclic sultones and the like. Specifically, alicyclic hydrocarbon groups represented by the following formulas can be mentioned. The bonding position of the alicyclic hydrocarbon group exemplified by the following formulas can be any position. TIFF2025105523000041.tif48165L b1 Among the hydrocarbon groups of, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-. Examples of the group in which -CH2- is replaced by -O- or -S- include a furan ring and a thiophene ring, respectively. Examples of the group in which -CH2- contained in the group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include those similar to the groups exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms. Examples of the group combining two or more of a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group include the group combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, the group combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, the group combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and the group combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group. The above combined groups are included. The group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group may be a condensed ring. L b2 Examples of the divalent hydrocarbon group of include a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group formed by removing one hydrogen atom from a combination of two or more of these groups, and a group that binds to Y b1 are included. L b2The divalent chain hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group formed by combining two or more of these groups, each within the range allowed by the number of carbon atoms, are L b1 Examples include groups obtained by removing one hydrogen atom from the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and group formed by combining two or more of these exemplified in b1 . L b1 and L b2 Examples of the substituents that the hydrocarbon groups of L b1 and L b2 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, an iodine atom, etc. L b1 and L b2 When L b1 and L b2 are groups formed by combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with a chain hydrocarbon group, substantially, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. Also, when the -CH2- of the chain hydrocarbon group contained in the hydrocarbon groups of L b1 and L b2 is replaced by -O-, -CO-, -S-, or -SO2-, the hydrocarbon groups of L b1 and L b2 can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, a sulfonyl group, etc. b1 and L b2 The number of substituents that L b1 and L b2 may have is not particularly limited, and they may have a plurality of substituents. b1 and L b2 L b1 and L b2 Examples of the cyclic hydrocarbon groups of Y b1 include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 Examples of the alicyclic hydrocarbon group and the aromatic hydrocarbon group of Y b1 are the same as those of the alicyclic hydrocarbon group and the aromatic hydrocarbon group exemplified in L b1 , and when they have no substituents, they may be a monovalent alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of Y b1 are each the same as those of the alicyclic hydrocarbon group and the aromatic hydrocarbon group exemplified in L b1 , and when they have no substituents, they may be a monovalent alicyclic hydrocarbon group and an aromatic hydrocarbon group. b1 Y b1 ​​Examples of the substituent that the methyl group may have include a halogen atom, a cyano group, a hydroxy group, and a nitro group. Y b1 Examples of the substituent that the cyclic hydrocarbon group of Y b1 may have include a halogen atom, a cyano group, a nitro group, or a hydrocarbon group having 1 to 18 carbon atoms which may have a halogen atom, a cyano group, and a nitro group. -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of Y b1 may have as a substituent include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these groups. Examples of the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and a group 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 same groups as the chain hydrocarbon group, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and a group combining two or more of these groups exemplified by L b1 are included. Also, Y b1 Examples of the group in which -CH2- contained in the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of Y b1 may have as a substituent is replaced by -O-, -S-, -CO-, or -SO2- include, within the range permitted by the upper limit of the number of carbon atoms, L b1 Examples of the same groups as the groups exemplified by the group in which -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -CO-, or -SO2- are included. Also, Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of Y b1 may have as a substituent may constitute a protecting group or a leaving group (an acid-labile group or a base-labile group) generally used in the art.

[0049] The anion of the salt represented by formula (B1) is preferably an anion represented by the following formula (B1-A1) or an anion represented by formula (B1-A2). TIFF2025105523000042.tif31125[In formula (B1-A1), L b2 and Y b1 represent the same meaning as in formula (I-A). Q b1 、Qb2 , 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 any integer from 0 to 6. When z1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. X 1 represents -O-CO-, -CO-O-, -O-CO-O-, or -O-. L b3 represents a single bond or an (nb2 + 1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. nb2 represents any integer from 1 to 3. When nb2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. Q b1 , Q b2 , Q b3 and Q b4 Examples of the alkyl group of Q, Q, Q, and Q 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 of Q, Q, Q, and Q 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 are Q b1 and Q b2 It is preferable that at least one of Q and Q contains a fluorine atom or a perfluoroalkyl group, more preferably a fluorine atom or a perfluoroalkyl group, still more preferably a fluorine atom or a trifluoromethyl group, and even more preferably both are fluorine atoms. Q b3 and Q b4 is preferably, independently of each other, a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b3 is preferably a hydrogen atom, a fluorine atom or a perfluoroalkyl group having 1 to 3 carbon atoms, and Q b4 is preferably a hydrogen atom or a fluorine atom. z1 is preferably any integer from 0 to 3, more preferably 0, 1 or 2. X 1 is preferably -O-CO- or -CO-O-.

[0050] L b3 As the hydrocarbon group in, within the range allowed by the upper limit of the number of carbon atoms, L of the formula (I-A) b1 is exemplified by the same hydrocarbon groups as those of L of the formula (I-A). In the formula (B1-A1), L b3 is preferably a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), an optionally substituted aromatic hydrocarbon group having 6 to 10 carbon atoms (wherein -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-), or a group formed by combining two or more of these groups, more preferably a single bond, a chain hydrocarbon group having 1 to 6 carbon atoms or a group represented by the following formula (Lb3-1). When -CH2- contained in the chain hydrocarbon group is replaced by -O- or -CO-, the number thereof is preferably 1 to 4, and it is preferable that one -CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO- or -CO-O-, or one -CH2-CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO-O-. TIFF2025105523000043.tif1582 [In the formula (Lb3-1), nb2 represents the same meaning as in the formula (B1-A1). L b31 represents a single bond or an aliphatic hydrocarbon group having 1 to 12 carbon atoms, and the -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-, and the aliphatic 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, and the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-, and the -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 bonding sites, and * represents the bonding site with X 1 and is represented. ]] In formula (Lb3-1), the aliphatic hydrocarbon group of L b31 , as long as the upper limit of the number of carbon atoms permits, is the same group as the aliphatic hydrocarbon group exemplified by L b1 . In formula (Lb3-1), the alicyclic hydrocarbon group and aromatic hydrocarbon group of W b3 , as long as the upper limit of the number of carbon atoms permits, is the same group as the alicyclic hydrocarbon group and aromatic hydrocarbon group exemplified by L b1 . In formula (Lb3-1), the substituents that the aliphatic hydrocarbon group of L b31 may have and the substituents that the alicyclic hydrocarbon group and aromatic hydrocarbon group of W b3 may have are the same groups as the substituents exemplified as the substituents that the hydrocarbon group of L b1 may have. L b31 is preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, as the alicyclic hydrocarbon group and aromatic hydrocarbon group of W b3 , the alicyclic hydrocarbon group and aromatic hydrocarbon group represented below are preferred. In the alicyclic hydrocarbon group and aromatic hydrocarbon group represented below, * and ** represent bonding sites, and * represents X 1 or L b31represents a binding site with, and ** represents a hydrogen atom, a substituent, or L b2 represents a binding site with, and at least one ** is L b2 represents a binding site with. In addition, in the alicyclic hydrocarbon group represented by the following, -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. When -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO-, or -SO2-, it preferably forms an ether ring, an ester ring (lactone), a carbonate ester ring, a sulfonic acid ester ring (sultone), or an acetal ring. In formula (B1-A1), L b2 is preferably a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), and is a single bond, -O-, -O-CO-, -CO-O-, -O-CO-O-, or *-L b21 -X 2 -L b22 -**(L b21 and L b22 either one of which 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. X 2 represents -O-, -CO-O-, -O-CO-, or -O-CO-O-. * and ** represent binding sites, and ** represents the binding site with Y b1 represents the binding site with. However, the total number of carbon atoms of L b21 , X 2 and L b22 is 12 or less. It is more preferably). In formula (B1-A1), Y b1is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and still more preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, it is preferably a group represented by the following formula (Y1) to formula (Y36). In formula (Y1) to formula (Y36), R Yb represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms among the substituents which the cyclic hydrocarbon group of Y b1 may have, R Yc represents a hydrogen atom or a substituent which the cyclic hydrocarbon group of Y b1 may have, and * represents a bonding site with L b2 . The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formulae may have, although not particularly shown in the following formulae, other substituents which the cyclic hydrocarbon group of Y b1 may have. TIFF2025105523000045.tif83159

[0051] As the anion in the salt represented by formula (B1), anions represented by formula (B1-A1-1) to formula (B1-A1-85) [hereinafter sometimes referred to as "anion (B1-A1-1)" etc. according to the formula number] are preferable, and an anion represented by any of formula (B1-A1-1) to formula (B1-A1-4), formula (B1-A1-9), formula (B1-A1-10), formula (B1-A1-24) to formula (B1-A1-33), formula (B1-A1-36) to formula (B1-A1-40), formula (B1-A1-47) to formula (B1-A1-85) is more preferable. TIFF2025105523000046.tif216159

[0052] TIFF2025105523000047.tif249150

[0053] TIFF2025105523000048.tif254164

[0054] Here, R i2 ~R i7 are, independently of each other, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R 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. L A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 represent the same meaning as described above. Specific examples of the anion represented by formula (B1-A1) include the anions described in JP-A-2010-204646.

[0055] Preferred anions in the salt represented by formula (B1) include the anions represented by formula (B1a-1) to formula (B1a-70), respectively. TIFF2025105523000049.tif185163

[0056] TIFF2025105523000050.tif252166

[0057] TIFF2025105523000051.tif69166

[0058] Among them, an anion represented by any one of formula (B1a-1) to formula (B1a-3), formula (B1a-7) to formula (B1a-19), and formula (B1a-22) to formula (B1a-70) is preferred.

[0059] The anion represented by formula (B1-A2) is represented by the following formula. TIFF2025105523000052.tif24100 In formula (B1-A2), L b2 of the hydrocarbon group and Y b1 Examples of the cyclic hydrocarbon group of are, within the range permitted by the upper limit of the number of carbon atoms, the examples of the hydrocarbon group of L in formula (B1) b2 and the examples of the cyclic hydrocarbon group of Y b1 are the same as those of the examples of the hydrocarbon group of L in formula (B1) and the examples of the cyclic hydrocarbon group of Y b2 of the hydrocarbon group, Y b1 of the methyl group and the substituents that the cyclic hydrocarbon group may have are also the same as the examples of the hydrocarbon group of L in formula (B1) b2 of the hydrocarbon group, Y b1 of the methyl group and the substituents that the cyclic hydrocarbon group may have. These hydrocarbon groups, methyl groups and cyclic hydrocarbon groups may have one substituent or a plurality of substituents. In formula (B1-A2), L b2 is preferably a chain hydrocarbon group having 1 to 12 carbon atoms (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), more preferably, *-CO-O-L b41 -(L b41 is a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms, and the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-. * represents the bonding site with the benzene ring to which SO3 - is bonded. L 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 (the -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably a cycloaliphatic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the cycloaliphatic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and Y of formula (B1-A1)b1 or L b1 It is more preferable that it is an alicyclic hydrocarbon group or an aromatic hydrocarbon group exemplified by. Specifically, it is preferably a group represented by the above-described formulas (Y1) to (Y36), and more preferably a group represented by the above-described formulas (Y1) to (Y19).

[0060] In formula (B1-A2), nb4 is preferably any integer from 1 to 4, more preferably any integer from 1 to 3, still more preferably 1 or 2, and even more preferably 2. When nb4 is 1 or 2, -L b2 -Y b1 The bonding position of is preferably the following structure which is the m-position substitution of the benzene ring with respect to the bonding position of SO3 - . TIFF2025105523000053.tif24105[In the above formula, L b2 , Y b1 , R b1 , and nb3 represent 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 preferably represent the same group as each other.

[0061] Examples of the alkyl group having 1 to 6 carbon atoms for R b1 include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, and hexyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, and more preferably 1 to 3. Examples of the halogen atom for R b1 include fluorine atom, chlorine atom, bromine atom, iodine atom and the like. Examples of the group in which -CH2- contained in the alkyl group is replaced by -O- or -CO- include hydroxy group, carboxy group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, oxy group, carbonyl group and the like. These replaced groups include those similar to the groups exemplified in the present specification within the range where the upper limit of the number of carbon atoms allows. R b1 is 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 by -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 by -O- or -CO-), and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group or a methyl group. nb3 is any integer from 0 to 4 (that is, nb3 - 1 is any integer from 0 to 3), preferably any integer from 0 to 3, and more preferably any integer from 0 to 2. In one embodiment, nb3 is preferably 0. In another embodiment, nb3 is preferably 1 or 2. When nb3 is 1, b1 R b1 is preferably a halogen atom, and b1 R b1 is more preferably a fluorine atom or an iodine atom. When nb3 is 2,

[0062] Examples of the anion (B1 - A2) include the following anions. Among them, the anions represented by formula (B2a - 1) to formula (B2a - 20) are preferred, and the anions represented by formula (B2a - 1) to formula (B2a - 11), formula (B2a - 16) to formula (B2a - 20) are more preferred. TIFF2025105523000054.tif94162

[0063] TIFF2025105523000055.tif1293[In formula (B3), all symbols have the same meanings as described above.] In formula (B3), L b2 ’ and Y b1Examples of the hydrocarbon group, cyclic hydrocarbon group, and their substituents in ’ are the same groups as L in formula (B1). b2 and Y b1 include the same groups. In formula (B3), L b2’ is a single bond, *-L b23 -X 2 - or *-L b23 -X 2 -W 2 -X 3 -(L b23 represents an alkanediyl group having 1 to 6 carbon atoms which may have a fluorine atom, X 2 and X 3 each independently represent -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-, and * represents the bonding site with SO2.). It is preferably so. In formula (B3), Y b1’ is preferably a trifluoromethyl group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or a phenyl group which may have a substituent, and more preferably a trifluoromethyl group or a group represented by formula (Y1) to formula (Y36) in formula (B1). nb5 is preferably 2 or 3. In formula (B3), when two SO2-L b2’ -Y b1’ together form a ring containing A 1 for example, an anion represented by formula (B3’) is included. TIFF2025105523000056.tif21113 [In formula (B3’), A 1 ,, nb5 represent the same meaning as in formula (B3). Y b1 , L b2 represent the same meaning as in formula (B1). W b4 represents a disulfonylimide ring or a disulfonylmethide ring having 3 to 12 carbon atoms which may have a fluorine atom.] Wb4 The disulfonylimide ring or disulfonylmethide ring is preferably a ring having 3 to 6 carbon atoms, and the hydrogen atoms of the methylene groups contained in the ring are preferably replaced by fluorine atoms.

[0064] Examples of the anion represented by formula (B3) include the following. Among them, the anions represented by formula (Ba3-1) and formula (Ba3-2) are preferred. TIFF2025105523000057.tif189164

[0065] In another embodiment of the acid generator (B), examples of the acid generator (B) in which the anion is a carboxylic acid anion include the following. TIFF2025105523000058.tif41155

[0066] Z1 + and Z2 + Examples of the organic cation of and include the same organic cations as the organic cation Z+ in salt (I). The acid generator (B) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. Examples of the acid generator (B) preferably include any anion represented by any of formula (B1a-1) to formula (B1a-3), formula (B1a-7) to formula (B1a-19), formula (B1a-22) to formula (B1a-70), formula (B2a-1) to formula (B2a-11), formula (B2a-16) to formula (B2a-20), formula (B3a-1) to formula (B3a-3) or formula (B3a-11) to formula (B3a-14), and a combination with cation (b2-1), cation (b2-2), cation (b2-3), cation (b2-4) or cation (b2-5).

[0067] As the acid generator (B), those represented by formula (B1-1) to formula (B1-105), formula (B2-1) to formula (B2-20) and formula (B3-1) to formula (B3-28) are preferably exemplified. Among them, those containing an arylsulfonium cation are preferred, and those represented by formula (B1-1) to formula (B1-3), formula (B1-5) to formula (B1-7), formula (B1-11) to formula (B1-14), formula (B1-20) to formula (B1-26), formula (B1-29), formula (B1-31) to formula (B1-105), formula (B2-1) to formula (B2-20) and formula (B3-1) to formula (B3-28) are particularly preferred. TIFF2025105523000059.tif198167

[0068] TIFF2025105523000060.tif244163

[0069] TIFF2025105523000061.tif254165

[0070] TIFF2025105523000062.tif254160

[0071] TIFF2025105523000063.tif249163

[0072] TIFF2025105523000064.tif250150

[0073] TIFF2025105523000065.tif186160

[0074] <Compound (L) containing phenolic hydroxyl group etc.> The resist composition of the present invention preferably further contains a compound having a phenolic hydroxyl group or a benzoic acid carboxy group and / or a compound in which the hydroxyl group of the phenolic hydroxyl group or the carboxy group of the benzoic acid carboxy group is protected by an acid-labile group. The compound (L) contains one or more structures represented by formula (L0) as partial structures. TIFF2025105523000066.tif2470[In formula (L0), Ar lk represents an aromatic hydrocarbon ring having 6 to 18 carbon atoms which may have a substituent. X lk represents a single bond or a carbonyl group. R lk represents a hydrogen atom or an acid-labile group. lk represents an integer of 1 or more. When lk is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. * represents a bonding site. lo represents an integer of 1 or more.] Ar lk Examples of the aromatic hydrocarbon ring of Ar include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring and the like. Ar lk Examples of the substituent that the aromatic hydrocarbon ring of Ar may have include the groups exemplified by R lk11 and R lk22 and the like, and the same groups as those exemplified by the groups described below. Ar lk is preferably a benzene ring or a naphthalene ring which may have a substituent, and more preferably a benzene ring which may have a substituent. R lk Examples of the acid-labile group of R include a group represented by formula (1a) (hereinafter, sometimes referred to as "acid-labile group (1a)"), and a group represented by formula (2a) (hereinafter, sometimes referred to as "acid-labile group (2a)"). Among them, the group represented by formula (2a) is preferable. TIFF2025105523000067.tif2156[In formula (1a), R aa1 , R aa2 and R aa3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these, or R aa1 and R aa2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a halogen atom. * represents a binding site. TIFF2025105523000068.tif2160[In formula (2a), R aa1’ and R aa2’ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R aa3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R aa2’ and R aa3’ are bonded to each other to form a heterocyclic group having 3 to 20 carbon atoms together with the -C-X a - to which they are bonded, and the -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X a represents an oxygen atom or a sulfur atom. * represents a binding site.

[0075] R aa1 R aa2 and R aa3 Examples of the alkyl group of R aa1 R aa2 and R aa3 include a methyl group, an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, etc. The number of carbon atoms of the alkyl group of R R aa1 R aa2 and R aa3 Examples of the alkenyl group of R R aa1 R aa2 and R aa3The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include, for example, decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* represents the bonding site). R aa1 、R aa2 and R aa3 The number of carbon atoms of the alicyclic hydrocarbon group of R, R and R is, for example, 3 to 20, preferably 3 to 18, more preferably 3 to 16, and still more preferably 3 to 12. TIFF2025105523000069.tif9159R aa1 、R aa2 and R aa3 Examples of the aromatic hydrocarbon group of R, R and R include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group and the like. R aa1 、R aa2 and R aa3 The number of carbon atoms of the aromatic hydrocarbon group of R, R and R is, for example, 6 to 18, preferably 6 to 14, and more preferably 6 to 10. Examples of the combined groups include groups combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group and the like), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group and the like), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group and the like), aryl-cycloalkyl groups such as phenylcyclohexyl group and the like.

[0076] R aa1 and R aa2When they are bonded to each other to form an alicyclic hydrocarbon group together with the carbon atoms to which they are bonded, -C(R aa1 )(R aa2 )(R aa3 ) includes the following groups. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and still more preferably 3 to 12. * represents the bonding site with -O-. TIFF2025105523000070.tif27138

[0077] Examples of the group represented by formula (1a) include a 1,1,1-trialkyl group (a group in which R aa1 , R aa2 and R aa3 in formula (1a) are alkyl groups, preferably a tert-butyl group), a 2-alkyladamantan-2-yl group (in formula (1a), R aa1 , R aa2 and the carbon atoms to which they are bonded form an adamantyl group, and R aa3 is an alkyl group), and a 1-(adamantan-1-yl)-1,1-dialkyl group (in formula (1a), R aa1 and R aa2 are alkyl groups, and R aa3 is an adamantyl group), etc.

[0078] Examples of the hydrocarbon groups of R aa1' , R aa2' and R aa3' include chain hydrocarbon groups such as alkyl groups, cyclic hydrocarbon groups such as alicyclic hydrocarbon groups and aromatic hydrocarbon groups, and groups formed by combining these. The alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and the group formed by combining these are the same as those exemplified for R aa1 , R aa2 and R aa3 . R aa2' and R aa3' are bonded to each other to form a heterocyclic group together with the carbon atoms to which they are bonded and X a , then -C(R aa1' )(R aa2' )-Xa -(R aa3' ) includes the following groups. * represents the bonding site. The number of carbon atoms in the heterocyclic group is, for example, 3 to 20, preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. TIFF2025105523000071.tif21143R aa1 , R aa2 , R aa3 , R aa1' , R aa2' and R aa3' The halogen atoms that R may have include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. R aa1' and R aa2' Among them, at least one of them is preferably a hydrogen atom.

[0079] Specific examples of the acid-labile group (1a) include the following groups. * represents the bonding site. TIFF2025105523000072.tif60162 Specific examples of the acid-labile group (2a) include the following groups. * represents the bonding site. TIFF2025105523000073.tif59148

[0080] lk may be any integer of 2 or more. Also, lk may be, for example, any integer of 13 or less. Among them, lk is preferably any integer of 1 to 11, more preferably any integer of 1 to 9, even more preferably any integer of 1 to 7, still more preferably any integer of 1 to 6, even more preferably any integer of 1 to 5, and even more preferably any integer of 1 to 4. lo may be any integer of 2 or more. Also, lo may be, for example, any integer of 13 or less. Among them, lo is preferably any integer of 1 to 11, more preferably any integer of 1 to 9, even more preferably any integer of 1 to 7, still more preferably any integer of 1 to 6, even more preferably any integer of 1 to 5, and even more preferably any integer of 1 to 4.

[0081] Examples of the compound (L) containing one or more structures represented by the formula (L0) as partial structures include compounds represented by the formula (LX). TIFF2025105523000074.tif23130[In the formula (LX), Ar k1 and Ar k2 each independently represent an aromatic hydrocarbon ring having 6 to 18 carbon atoms. X lk1 and X lk2 each independently represent a single bond or a carbonyl group. R lk1 and R lk2 each independently represent a hydrogen atom or an acid-labile group. Lx represents a hydrocarbon group having 1 to 80 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. R lk11 and R lk22 each independently represent a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. R lk11 and R lk22 , R lk11 and Lx or R lk22 and Lx may each combine to form a ring, the ring may have a substituent, and -CH2- contained in the ring may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. lx2 represents any integer from 1 to 6, and when lx2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. lk1’ represents any integer from 1 to 13, and when lk1’ is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. lk11’ represents any integer from 0 to 12, and when lk11’ is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. lk2’ represents any integer from 1 to 13. When lk2’ is 2 or more, the groups within the plurality of parentheses may be the same as or different from each other. lk22’ represents any integer from 0 to 12. When lk22’ is 2 or more, the groups within the plurality of parentheses may be the same as or different from each other.] Ar k1 and Ar k2 Examples of the aromatic hydrocarbon ring of Ar lk include the same groups as those exemplified for the aromatic hydrocarbon ring of Ar R lk1 and R lk2 Examples of the acid-labile group of R lk include the same groups as those exemplified for the acid-labile group of R Examples of the hydrocarbon group of Lx include a chain hydrocarbon group, a monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.) alicyclic hydrocarbon group, and an aromatic hydrocarbon group, and a group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group) may also be used. The hydrocarbon group of Lx is a (lx2 + 1)-valent hydrocarbon group, and depending on lx2, it can be a 2- to 7-valent hydrocarbon group. The number of carbon atoms of the hydrocarbon group is preferably from 1 to 72, more preferably from 1 to 60, still more preferably from 1 to 48, even more preferably from 1 to 36, and even more preferably from 1 to 24. Examples of the chain hydrocarbon group include an alkanediyl group and the like. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-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, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group; and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. Note that the terminal of the branched alkanediyl group may be a methyl group. In addition, examples of the chain hydrocarbon group include a group in which one or more hydrogen atoms of the above-described group are replaced at the bonding site. The number of carbon atoms of the chain hydrocarbon group is preferably from 1 to 18, more preferably from 1 to 12, preferably from 1 to 10, even more preferably from 1 to 9, still more preferably from 1 to 8, even more preferably from 1 to 6, and even more preferably from 1 to 4. Examples of the alicyclic hydrocarbon group include monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group; polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group; spirocyclic alicyclic hydrocarbon groups such as spirocyclohexane-1,2′-cyclopentane group and spiroadamantane-2,3′-cyclopentane group; and spiro rings having a cycloalkyl group spiro-bonded to a norbornyl group or an adamantyl group, respectively. Examples of the alicyclic hydrocarbon group also include groups in which one or more hydrogen atoms of the above-described groups are replaced at the bonding site. Examples of the alicyclic hydrocarbon group include the following groups, etc. The bonding site can be at any position. TIFF2025105523000075.tif44163 The number of carbon atoms in the alicyclic hydrocarbon group is from 3 to 72, may be from 3 to 60, preferably from 3 to 24, more preferably from 3 to 20, still more preferably from 3 to 18, even more preferably from 3 to 16, and even more preferably from 3 to 12. Examples of the aromatic hydrocarbon group include aromatic hydrocarbon groups such as arylene groups such as phenylene group, naphthylene group, anthrylene group, biphenylene group, phenanthrylene group, etc. Examples of the aromatic hydrocarbon group also include groups in which one or more hydrogen atoms of the above-described groups are replaced at the bonding site. The number of carbon atoms in the aromatic hydrocarbon group is from 6 to 72, may be from 6 to 60, preferably from 6 to 24, more preferably from 6 to 20, still more preferably from 6 to 18, even more preferably from 6 to 14, and even more preferably from 6 to 10. Examples of the group formed by combining two or more types include a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group, a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group, and a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. In the combination, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and the chain hydrocarbon group may each be combined with two or more types. Also, any group may be bonded to Ar k1 or Ar k2 and may be bonded thereto. Examples of the group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group include, for example, -alicyclic hydrocarbon group-chain hydrocarbon group-, -chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-, -chain hydrocarbon group-alicyclic hydrocarbon group-, etc. Examples of a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group include -aromatic hydrocarbon group-chain hydrocarbon group-, -chain hydrocarbon group-aromatic hydrocarbon group-chain hydrocarbon group-, -chain hydrocarbon group-aromatic hydrocarbon group-, and the like. Examples of a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group include -aromatic hydrocarbon group-alicyclic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-, and the like. In addition, examples of the combined group include a group in which one or more hydrogen atoms of the above-described groups are replaced at the bonding site. The -CH2- contained in the hydrocarbon group of Lx may be replaced by -O-, -S-, -SO2- or -CO-. Examples of a group in which -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include, as described above, a hydroxy group, a carboxy group, a thiol group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkoxy group, an alkylthio group, an alkylsulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkanedioxy group, an alkanedioxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, a group formed by combining two or more of these groups, and the like. These replaced groups include those similar to the groups exemplified in the present specification within the range where the upper limit of the number of carbon atoms permits. In addition, examples of a group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include those similar to the groups exemplified in the present specification within the range where the upper limit of the number of carbon atoms permits. Examples of a group in which -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a group in which one or more hydrogen atoms of the above-described groups are replaced at the bonding site. Examples of the substituent that Lx may have include, for example, a halogen atom, a cyano group, and the like. When Lx is a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with a chain hydrocarbon group such as an alkyl group, the chain hydrocarbon group such as an alkyl group can be a substituent of the alicyclic hydrocarbon group or the aromatic hydrocarbon group. By replacing -CH2- contained in the chain hydrocarbon group such as an alkyl group contained in Lx with -O-, -CO-, -S- or -SO2-, Lx can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, a sulfonyl group, and the like. Examples of the substituent that Lx may have include R lk11 and R lk22 and the like, and groups similar to the groups exemplified by the following.

[0082] R lk11 and R lk22 Examples of the halogen atom of R and R include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. R lk11 and R lk22 Examples of the hydrocarbon group of R and R include chain hydrocarbon groups such as an alkyl group and an alkanediyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and groups formed by combining these. The alkyl group is a straight-chain or branched alkyl group, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, and the like. The alkandiyl group is a linear or branched alkandiyl group, including linear alkandiyl groups such as methylene group, ethylene group, propane-1,3-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, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group and heptadecane-1,17-diyl group, and branched alkandiyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group. The terminal of the branched alkandiyl group may be a methyl group. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the alicyclic hydrocarbon group include the groups represented below. The bonding site can be at any position. TIFF2025105523000076.tif43163Specifically, examples of the monocyclic alicyclic hydrocarbon group include monocyclic cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclododecyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group and the like. Examples of the spirocyclic alicyclic hydrocarbon group include cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane group, spiroadamantane-2,3'-cyclopentane group, and spiro rings having a cycloalkyl group spiro-bonded to a norbornyl group or an adamantyl group respectively. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and still more preferably 3 to 12. Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, biphenyl group, anthryl group, phenanthryl group, binaphthyl group and the like. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and still more preferably 6 to 10. Examples of the group formed by combining two or more groups include a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group (e.g., aromatic hydrocarbon group - alkane diyl group - *, alkyl group - aromatic hydrocarbon group - *, alkyl group - aromatic hydrocarbon group - alkane diyl group - *, wherein -CH2- contained in the alkane diyl group and the alkyl group may be replaced by -O-, -CO-, -S- or -SO2-), a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group (e.g., alicyclic hydrocarbon group - alkane diyl group - *, alkyl group - alicyclic hydrocarbon group - *, alkyl group - alicyclic hydrocarbon group - alkane diyl group - *, wherein -CH2- contained in the alicyclic hydrocarbon group, the alkane diyl group and the alkyl group may be replaced by -O-, -CO-, -S- or -SO2-), and a group formed by combining an aromatic hydrocarbon group and an alicyclic hydrocarbon group (e.g., aromatic hydrocarbon group - alicyclic hydrocarbon group - *, alicyclic hydrocarbon group - aromatic hydrocarbon group - *, wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2). * represents a bonding site. Examples of the aromatic hydrocarbon group - alkane diyl group - * include aralkyl groups such as benzyl group and phenethyl group. Examples of the alkyl group - aromatic hydrocarbon group - * include tolyl group, xylyl group, cumenyl group and the like. Examples of the alicyclic hydrocarbon group - alkane diyl group - * include cycloalkylalkyl groups such as cyclohexylmethyl group, cyclohexylethyl group, 1-(adamantan-1-yl)methyl group, 1-(adamantan-1-yl)-1-methylethyl group and the like. Examples of the alkyl group - alicyclic hydrocarbon group - * include cycloalkyl groups having an alkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, 2-alkyladamantan-2-yl group and the like. Examples of the aromatic hydrocarbon group - alicyclic hydrocarbon group - * include phenylcyclohexyl group and the like. Examples of the alicyclic hydrocarbon group - aromatic hydrocarbon group - * include cyclohexylphenyl group and the like. In the combination, the alicyclic hydrocarbon group, aromatic hydrocarbon group, and chain hydrocarbon group may be combined in two or more kinds respectively. Also, any of the groups may be bonded to the benzene ring. R lk11 and R lk22 When -CH2- contained in the hydrocarbon group represented by is replaced by -O-, -CO-, -S- or -SO2-, the carbon number before replacement is defined as the total carbon number of the hydrocarbon group. Also, the number may be one or two or more. Examples of the group in which -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include the same groups as those exemplified by Lx within the range where the upper limit of the carbon number allows. R lk11 and R lk22 Examples of the substituent that the hydrocarbon group of may have include a halogen atom, a cyano group, and the like. R lk11 and R lk22 When is a hydrocarbon group having a halogen atom, examples of the hydrocarbon group having a halogen atom of lk11 and R lk22 include a chain hydrocarbon group having a halogen atom such as a haloalkyl group, an alicyclic hydrocarbon group having a halogen atom, and an aromatic hydrocarbon group having a halogen atom. The haloalkyl group represents an alkyl group having a halogen atom. Examples of the haloalkyl group include haloalkyl groups having 1 to 12 carbon atoms such as alkyl fluoride groups having 1 to 12 carbon atoms, alkyl chloride groups having 1 to 12 carbon atoms, alkyl bromide groups having 1 to 12 carbon atoms, and alkyl iodide groups having 1 to 12 carbon atoms. Specific examples of the haloalkyl group include perfluoroalkyl groups having 1 to 12 carbon atoms (such as trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, etc.), 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, iodomethyl group, etc. The number of carbon atoms of the haloalkyl group is preferably 1 to 9, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. -CH2- contained in the haloalkyl group may be replaced by -O- or -CO- etc. Examples of such groups include haloalkoxy groups, haloalkoxycarbonyl groups, haloalkylcarbonyl groups, haloalkylcarbonyloxy groups, etc. Specifically, haloalkoxy groups having 1 to 11 carbon atoms, haloalkoxycarbonyl groups having 2 to 11 carbon atoms, haloalkylcarbonyl groups having 2 to 12 carbon atoms, haloalkylcarbonyloxy groups having 2 to 11 carbon atoms, etc. are included. For example, groups in which one or more hydrogen atoms of the groups exemplified above are replaced by halogen atoms are included. The hydrocarbon group may have one substituent or a plurality of substituents.

[0083] Examples of the compound (LX) include a compound represented by the formula (LX-0) (hereinafter sometimes referred to as "compound (LX-0)"). As the compound (LX-0), a compound represented by the formula (LX-1) (hereinafter sometimes referred to as "compound (LX-1)") is preferred. TIFF2025105523000077.tif23125[In the formula (LX-0), symbols other than the following have the same meanings as described above. lk1 represents any integer from 1 to 5. When lk1 is 2 or more, the groups within the plurality of parentheses may be the same as or different from each other. lk11 represents any integer from 0 to 4, satisfies 1 ≦ lk1 + lk11 ≦ 5, and when lk11 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. lk2 represents any integer from 1 to 5, and when lk2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. lk22 represents any integer from 0 to 4, satisfies 1 ≦ lk2 + lk22 ≦ 5, and when lk22 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. TIFF2025105523000078.tif42147 [In formula (LX-1), the symbols other than the following represent the same meaning as described above. X lk3 represents a single bond or a carbonyl group. R lk3 represents a hydrogen atom or an acid-labile group. Lx1 and Lx2 each independently represent a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. R lk33 represents a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. lx3 represents any integer from 0 to 6, and when lx3 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. lk3 represents any integer from 1 to 4, and when lk3 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. lk33 represents any integer from 0 to 3, satisfies 1 ≦ lk3 + lk33 ≦ 4, and when lk33 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. The hydrocarbon group which may have substituents of Lx1 and Lx2 (wherein -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) includes, within the range permitted by the upper limit of the number of carbon atoms etc., a hydrocarbon group which may have the substituents exemplified by Lx (wherein -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), and the like. R lk33 The halogen atom or the hydrocarbon group which may have a substituent of lk33 (wherein -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) includes, within the range permitted by the upper limit of the number of carbon atoms etc., a hydrocarbon group which may have the halogen atom or the substituent exemplified by R lk11 and R lk22 and the like, which may have the halogen atom or the substituent exemplified by R R lk11 and Lx1, or R lk22 and Lx2 may each be bonded to each other to form a ring. In this case, the ring may be a condensed ring which condenses with the benzene ring or a spiro ring which is spiro-bonded to the benzene ring, since R lk11 and R lk22 are each bonded to the benzene ring. The total number of carbon atoms of this condensed ring or spiro ring is, for example, 3 to 28, may be 3 to 24, and is preferably 3 to 20. The condensed ring or spiro ring may be a ring containing one or more of -O-, -CO-, -S- or -SO2-. In the benzene ring (-R lk11 )-Lx1- or the benzene ring (-R lk22 )-Lx2-, examples of the ring formed by the bonding of R lk11 and Lx1 or R lk22 and Lx2 include, for example, the following groups etc. Although the description of the following groups is omitted, they have at least one R lk1 -O-X lk1 - or R lk2 -O-X lk2 -, and may have other R lk11 or R lk22 . * represents the bonding site to the benzene ring. TIFF2025105523000079.tif20123R lk11 and R lk22 may be bonded to each other to form a ring. Examples of the ring in this case include rings having a structure represented by the formula (LX-13) described later, etc.

[0084] As the compound (LX-1), compounds represented by the formula (LX-11), the formula (LX-12), and the formula (LX-13) (hereinafter, may be referred to as "compound (LX-11)", "compound (LX-12)", and "compound (LX-13)", respectively) are preferable. TIFF2025105523000080.tif142158[In the formula (LX-11), the formula (LX-12), and the formula (LX-13), symbols other than the following represent the same meaning as described above. Ly represents a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. Examples of the hydrocarbon group having a substituent which may be possessed by Ly (wherein -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) include hydrocarbon groups having a substituent exemplified by Lx within the range allowed by the upper limit of the number of carbon atoms, etc. (wherein -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), which are the same as those groups. lk1 and lk2 are each independently preferably any integer from 1 to 4, more preferably any integer from 1 to 3, and still more preferably 1 or 2. lk11 and lk22 are each independently preferably any integer from 0 to 3, and more preferably any integer from 0 to 2. lk3 is preferably any integer from 1 to 3, and more preferably 1 or 2. lk33 is preferably any integer from 0 to 2. lx2 is preferably an integer of 1 to 5, more preferably an integer of 1 to 4, even more preferably an integer of 1 to 3, and even more preferably 1 or 2. lx3 is preferably an integer of 0 to 5, more preferably an integer of 0 to 4, even more preferably an integer of 0 to 3, and even more preferably an integer of 0 to 2. R lk11 , R lk22 and R lk33 are each independently preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the haloalkyl group or the alkyl group may be replaced with -O- or -CO-), more preferably a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-), even more preferably an iodine atom, a fluorine atom, a fluorinated alkyl group having 1 to 3 carbon atoms, a hydroxy group, a carboxy group, an alkoxy group having 1 to 3 carbon atoms, a hydroxyalkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 3 carbon atoms, and even more preferably an iodine atom, a fluorine atom, a trifluoromethyl group, a hydroxy group, a carboxy group, a methoxy group, or a methyl group. Lx1, Lx2 and Ly are each independently a linear hydrocarbon group having 1 to 10 carbon atoms (wherein -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-), or a combination of a linear hydrocarbon group having 1 to 6 carbon atoms and a cyclic hydrocarbon group having 3 to 18 carbon atoms (wherein -CH2- contained in the linear hydrocarbon group and the cyclic hydrocarbon group may be replaced by -O- or -CO-). Preferably, it is a linear hydrocarbon group having 1 to 8 carbon atoms (wherein -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-), or a combination of a linear hydrocarbon group having 1 to 4 carbon atoms and a cyclic hydrocarbon group having 3 to 16 carbon atoms (wherein -CH2- contained in the linear hydrocarbon group and the cyclic hydrocarbon group may be replaced by -O- or -CO-). More preferably, it is a linear hydrocarbon group having 1 to 6 carbon atoms or a combination of a linear hydrocarbon group having 1 to 4 carbon atoms and a cyclic hydrocarbon group having 3 to 12 carbon atoms. Also, R lk11 and Lx1 or R lk22 and Lx2 each preferably combine to form a ring, and R lk11 and R lk22 preferably combine to form a ring.

[0085] In one embodiment, the compound (L) may be a low molecular weight compound. A low molecular weight compound is a compound having a molecular weight of less than 10,000. When the compound (L) is a low molecular weight compound, the weight average molecular weight is preferably 7,500 or less, more preferably 5,000 or less, further preferably 4,000 or less, still more preferably 3,000 or less, even more preferably 2,500 or less, even more preferably 2,000 or less, and still more preferably 1,500 or less. Also, it is preferably 100 or more, more preferably 120 or more, further preferably 150 or more, still more preferably 300 or more.

[0086] Among the compounds (L), the compound (X) containing an aromatic hydrocarbon ring having a hydroxy group lkis a single bond, and R lk Examples of the compound in which is a hydrogen atom) include compounds represented by the following formula. TIFF2025105523000081.tif180164 Among the compounds (L), the compound (X) containing an aromatic hydrocarbon ring having a carboxy group lk is a carbonyl group, and R lk Examples of the compound in which is a hydrogen atom) include compounds in which at least one hydroxy group of the above compound is replaced with a carboxy group. In the compound (L), it may have both a hydroxy group and a carbonyl group.

[0087] Examples of the low molecular weight compound in which the hydroxy group of the phenolic hydroxy group is protected with an acid-labile group and the low molecular weight compound in which the carboxy group of benzoic acid is protected with an acid-labile group include compounds represented by the following formula. TIFF2025105523000082.tif205165 Examples of the compound in which the carboxy group of the compound containing an aromatic hydrocarbon ring having a carboxy group among the compounds (L) is protected with an acid-labile group include compounds in which at least one ethoxyethoxy group of the above compound is replaced with an ethoxyethoxycarbonyl group. In the compound (L), it may have both an ethoxyethoxy group and an ethoxyethoxycarbonyl group.

[0088] In the resist composition of the present invention, when it contains a low molecular weight compound of the compound (L), the total content of the low molecular weight compound having a phenolic hydroxy group, the low molecular weight compound having a phenylcarboxy group, the low molecular weight compound in which the hydroxy group of the phenolic hydroxy group is protected with an acid-labile group, and the low molecular weight compound in which the carboxy group of the phenylcarboxy group is protected with an acid-labile group is 0.1% by mass or more and 90% by mass or less, preferably 0.3% by mass or more and 45% by mass or less, more preferably 0.5% by mass or more and 40% by mass or less, and still more preferably 1% by mass or more and 35% by mass or less based on the solid content of the resist composition.

[0089] In another embodiment, the compound having a phenolic hydroxyl group or a benzoic acid carboxyl group and / or the compound (L) in which the hydroxyl group of the phenolic hydroxyl group or the carboxyl group of the benzoic acid carboxyl group is protected with an acid-labile group may be a resin. When the compound (L) is a resin, it is preferably a resin (A) containing a structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as the structural unit (a2-A)) and / or a structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as the structural unit (a1-4)). TIFF2025105523000083.tif30128[In the formula (a2-A), all the symbols have the same meanings as described above respectively.] TIFF2025105523000084.tif31119[In the formula (a1-4), all the symbols have the same meanings as described above respectively.] R a2 and R a1 、R a27 and R a17 Examples of the halogen atom in R, R, R, and R include a fluorine atom, a chlorine atom, and a bromine atom. R a2 and R a1 、R a27 and R a17 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R, R, R, and R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, more preferably 1 to 3, and still more preferably 1 or 2. R a2 and R a1is 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 still more preferably a hydrogen atom or a methyl group.

[0090] A a21 and A a11 Examples of the alkanediyl group of and A include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, etc. The number of carbon atoms of the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, still even more preferably 1 to 3, and still more preferably 1 or 2. R a28 and R a18 Examples of the alkyl group of and R include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, and tert-butyl group. A a21 and A a11 When the -CH2- contained in the alkanediyl group of and A is replaced by -O-, -CO- or -NR a28 - or -NR a18 -, the number of carbon atoms before replacement is taken as the number of carbon atoms of the hydrocarbon group. A a21 and A a11The group in which -CH2- contained in the alkanediyl group is replaced by -O- or -CO- includes a hydroxy group (the group in which -CH2- contained in the methyl group is replaced by -O-), a carboxy group (the group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), a carbonyl group (the group in which -CH2- contained in the methylene group is replaced by -CO-), an oxy group (the group in which -CH2- contained in the methylene group is replaced by -O-), an amino group (the group in which -CH2- contained in the alkanediyl group is replaced by -NR a28 - or -NR a18 -, an alkoxy group (the group in which any -CH2- contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (the group in which any -CH2-CH2- contained in the alkyl group is replaced by -O-CO-), an alkylcarbonyl group (the group in which any -CH2- contained in the alkyl group is replaced by -CO-), an alkylamino group (the group in which -CH2- contained in the alkyl group is replaced by -NR a28 - or -NR a18 -, etc. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. Examples of the alkylamino group include alkylamino groups having 1 to 11 carbon atoms, such as methylamino group, ethylamino group, propylamino group, butylamino group, pentylamino group, hexylamino group, octylamino group, etc. The number of carbon atoms of the alkylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylamino group include alkanediylamino groups having 1 to 11 carbon atoms, such as methyleneamino group, ethyleneamino group, propyleneamino group, etc. The number of carbon atoms of the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Among them, -CH2- contained in the alkanediyl group of A a21 is replaced by -O-, -CO- or -NR a28The groups replaced are *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a22 -CO-O-, *-O-CO-A a22 -O-, *-O-A a22 -CO-O-, *-CO-O-A a22 -O-CO-, *-O-CO-A a22 -O-CO-, etc. Among them, *-CO-O-, *-CO-O-A a22 -CO-O- or *-O-A a22 -CO-O-, *-CO-NR a28 - are preferred. Here, A a22 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site to the carbon atom to which R a2 is bonded. The alkanediyl group of A a22 includes, within the range allowed by the upper limit of the number of carbon atoms, the same alkanediyl group as A a21 . Also, the -CH2- contained in the alkanediyl group of A a11 is replaced by -O-, -CO- or -NR a18 -. The groups replaced are *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a12 -CO-O-, *-O-CO-A a12 -O-, *-O-A a12 -CO-O-, *-CO-O-A a12 -O-CO-, *-O-CO-A a12 -O-CO-, *-CO-NR a18 -. Among them, *-CO-O-, *-CO-O-A a12 -CO-O-, *-O-A a12 -CO-O-, *-CO-NR a18 - are preferred. Here, A a12 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site with the carbon atom to which R a1 is bonded. The alkanediyl group of A a12 includes, within the range allowed by the upper limit of the number of carbon atoms, the same alkanediyl group as A a11 . A a21 is a single bond, *-CO-O- or *-CO-O-A a22-CO-O- is preferred, more preferably a single bond, *-CO-O- or *-CO-O-CH2-CO-O-, and even more preferably a single bond or *-CO-O-. A a11 is a single bond, *-CO-O- or *-CO-O-A a12 -CO-O- is preferred, more preferably a single bond, *-CO-O- or *-CO-O-CH2-CO-O-, and even more preferably a single bond or *-CO-O-.

[0091] R a27 and R a17 Examples of the alkoxy group of R and R include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, and tert-butoxy group. The number of carbon atoms of the alkoxy group is preferably 1 to 4, more preferably 1 to 3, even more preferably methoxy group or ethoxy group, and still more preferably methoxy group. R a27 and R a17 Examples of the alkoxyalkyl group of R and R include methoxymethyl group, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, and tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably methoxymethyl group or ethoxyethyl group, and even more preferably methoxymethyl group. R a27 and R a17 Examples of the alkoxyalkoxy group of R and R include methoxymethoxy group, methoxyethoxy group, ethoxymethoxy group, ethoxyethoxy group, propoxymethoxy group, isopropoxymethoxy group, butoxymethoxy group, sec-butoxymethoxy group, and tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably methoxyethoxy group or ethoxyethoxy group. R a27 and R a17Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and more preferably an acetyl group. R a27 and R a17 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and more preferably an acetyloxy group. R a27 and R a17 are 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 ethoxy methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nA2 is preferably 1, 2, 3, or 4, more preferably 1, 2, or 3, and even more preferably 1 or 2. na21 is preferably 0, 1, 2, or 3, more preferably 0, 1, or 2, and even more preferably 0 or 1. mc is preferably 0 or 1. -X a2 -OH, in the case of a benzene ring, may be bonded to any of the o-position, m-position, or p-position with respect to the bonding position of A a21 . Among them, at least one is preferably bonded to the m-position or p-position, and more preferably bonded to the m-position. In the case of a naphthalene ring, when the bonding position of A a21 is at the 1-position, it may be bonded to any of the 2nd to 8th positions, and when the bonding position of A a21 is at the 2nd position, it may be bonded to any of the 1st and 3rd to 8th positions. Among them, when the bonding position of A a21 is at the 1st position, at least one is preferably bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. A a21When 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.

[0092] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A-2010-204634 and JP-A-2012-12577. Examples of the structural unit (a2-A) include structural units represented by formula (a2-2-1) to formula (a2-2-32), formula (a2-3-1) to formula (a2-3-24), and in the structural units represented by formula (a2-2-1) to formula (a2-2-32), formula (a2-3-1) to formula (a2-3-24), the methyl group corresponding to R a2 in the structural unit (a2-A) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. TIFF2025105523000085.tif107169

[0093] When the resin contains the structural unit (a2-A), the content of the structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 15 mol% or more, and even more preferably 20 mol% or more with respect to all the structural units. Also, it is preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, still more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%. The structural unit (a2-A) is a compound that induces the structural unit (a2-A) (for example, -CH2-C(-R a2 )- of the structural unit (a2-A) is CH2=C(-R of the double bond before cleavage a2The structural unit (a2-A) can be incorporated into the resin (A) by polymerizing a compound (a2-A') in the state of (a1-4) or the like. Alternatively, the structural unit (a2-A) can be incorporated into the resin by polymerizing the structural unit (a1-4) and then treating with an acid such as p-toluenesulfonic acid. Alternatively, the structural unit (a2-A) can be incorporated into the resin by polymerizing the structural unit (a1-4) and then treating with an alkali such as tetramethylammonium hydroxide.

[0094] na1 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na11 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and further preferably 0 or 1. mc is preferably 0 or 1. R a34 , R a35 and R a36 Examples of the hydrocarbon group in include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group consisting of a combination thereof. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl, adamantyl, and norbornyl groups, as well as the following groups (* indicates a bonding site): TIFF2025105523000087.tif10151 Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a phenanthryl group. Examples of the combined group include a group formed by combining the above-described alkyl group and alicyclic hydrocarbon group (e.g., an alkylcycloalkyl group or cycloalkylalkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornil group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), an aralkyl group such as benzyl group, an aromatic hydrocarbon group having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), an aromatic hydrocarbon group having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), an aryl-cycloalkyl group such as phenylcyclohexyl group, etc. In particular, R a36 Examples of R 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. a35 Examples of the divalent hydrocarbon group having 2 to 20 carbon atoms formed by R a36 and R a34 being bonded to each other and together with the -C-O- to which they are bonded include, for example, the following groups. * represents the bonding site, and one side is the bonding site with R TIFF2025105523000088.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, more preferably a methyl group or an ethyl group. R a36 The hydrocarbon group of R a36The alkyl group and alicyclic hydrocarbon group in are preferably unsubstituted. R a36 The aromatic hydrocarbon group in preferably has an aromatic ring having an aryloxy group with 6 to 10 carbon atoms.

[0096] -OC(R a34 )(R a35 )-O-R a36 in the structural unit (a1-4) eliminates 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 )-O-R a36 is In the case of a benzene ring, it may be bonded to any of the o-position, m-position, or p-position with respect to the bonding position of A a11 . Among them, it is preferably bonded to at least one of the o-position or p-position, and more preferably bonded to the p-position. In the case of a naphthalene ring, when the bonding position of A a11 is at the 1-position, it may be bonded to any of the 2-position to 8-position, and when the bonding position of A a11 is at the 2-position, it may be bonded to any of the 1-position and 3-position to 8-position. Among them, when the bonding position of A a11 is at the 1-position, it is preferably bonded to at least one of the 3-position to 6-position, and more preferably bonded to the 3-position or 4-position. When the bonding position of A a11 is at the 2-position, it is preferably bonded to the 4-position to 7-position, and more preferably bonded to the 5-position or 6-position.

[0097] Examples of the structural unit (a1-4) include structural units derived from the monomers described in JP-A-2010-204646. Preferably, the structural units represented by formula (a1-4-1) to formula (a1-4-42) and the structural unit in which the hydrogen atom corresponding to R a1 in the structural unit (a1-4) is replaced by a halogen atom, a haloalkyl group, or an alkyl group are mentioned, and more preferably, the structural units represented by formula (a1-4-1) to formula (a1-4-5), formula (a1-4-10), formula (a1-4-13), and formula (a1-4-14) are mentioned. When the resin contains the structural unit (a1-4), its content is 5 to 95 mol%, 5 to 60 mol%, 5 to 50 mol% based on the total of all the structural units of the resin, and preferably 10 to 40 mol%, 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, still even more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol%.

[0098] When the resin is included in the resist composition of the present invention, the resin may contain structural units other than the structural unit represented by the formula (a2-A) and the structural unit represented by the formula (a1-4). Examples of the structural units other than the structural unit represented by the formula (a2-A) and the structural unit represented by the formula (a1-4) include structural units having an acid-labile group other than the structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as "structural unit (a1)"), structural units having no acid-labile group other than the structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as "structural unit (s)"), and structural units derived from other monomers known in the art, etc.

[0099] 〈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 is preferably a group represented by the formula (1) (hereinafter also referred to as group (1)) and / or a group represented by the formula (2) (hereinafter also referred to as group (2)). TIFF2025105523000090.tif2298 [In the formula (1), R a1 , R a2 and R a3 each independently represent an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these, or R a1 and R a2are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded, and the alkyl group, alkenyl group, alicyclic hydrocarbon group, and 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. * represents a bonding site. TIFF2025105523000091.tif2278[In formula (2), R a1’ and R a2’ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and 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 a heterocyclic group having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded and X, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bonding site.

[0100] R a1 , R a2 and R a3 Examples of the alkyl group in R R a1 , R a2 and R a3 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, etc. R a1 , R a2 and R a3The alicyclic hydrocarbon group in [the compound] may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, etc. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups (* represents the bonding site). R a1 and R a2 and R a3 The number of carbon atoms of the alicyclic hydrocarbon groups of R TIFF2025105523000092.tif10159R a1 and R a2 and R a3 Examples of the aromatic hydrocarbon group in [the compound] include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group, etc. Examples of the combined groups include groups combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), aryl-cycloalkyl groups such as phenylcyclohexyl group, etc. Preferably, ma is 0 and na is 1. R a1 and R a2 When R a1 and R a2 and R a3 are bonded to each other to form an alicyclic hydrocarbon group, examples of -C(R TIFF2025105523000093.tif28139

[0101] R a1’ 、R a2’ and R a3’ Examples of the hydrocarbon group in R Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and the group formed by combining these include those similar to the groups exemplified for R a1 、R a2 and R a3 When R and R a2’ are bonded to each other to form a heterocyclic ring together with the carbon atom to which they are bonded and X, examples of -C(R a3’ )(R a1’ )(R a2’ )-X-R a3’ include the following rings. * represents the bonding site. TIFF2025105523000094.tif19124R a1 、R a2 、R a3 、R a1 、R a2’ and R a3’ Examples of the halogen atom that R 、R a1’ and R a2’ may have include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. na’ is preferably 0.

[0102] Examples of the group (1) include the following groups. In formula (1), when R a1 、R a2 and R a3 are alkyl groups, ma = 0, and na = 1. Examples of such a group include a tert-butoxycarbonyl group. In formula (1), a1 、R a2together 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 group. In formula (1), R a1 and R a2 are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and na = 1 group. Specific examples of group (1) include the following groups. * represents a bond. TIFF2025105523000095.tif150162

[0103] Specific examples of group (2) include the following groups. * represents a bond. TIFF2025105523000096.tif55153

[0104] 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. Among the (meth)acrylic monomers having an acid-labile group, preferably those having an alicyclic hydrocarbon group with 5 to 20 carbon atoms are mentioned. If a resin having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

[0105] As the structural unit derived from the (meth)acrylic monomer having the group (1), there may be mentioned a structural unit represented by the formula (a1-0) (hereinafter sometimes referred to as the structural unit (a1-0)), a structural unit represented by the formula (a1-1) (hereinafter sometimes referred to as the structural unit (a1-1)), or a structural unit represented by the formula (a1-2) (hereinafter sometimes referred to as the structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1), and the structural unit (a1-2), more preferably at least one or two structural units selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2025105523000097.tif44141[In the formula (a1-0), the formula (a1-1), and the formula (a1-2), all the symbols have the same meanings as described above respectively.]

[0106] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. R a01 、R a4 、R a5 Examples of the alkyl group of R R a01 、R a4 and R a5 are preferably a hydrogen atom or a methyl group, more preferably a methyl group. L a01 、L a1 and L a2 are preferably an oxygen atom or *-O-(CH2) k01 -CO-O- (wherein k01 is preferably any integer from 1 to 4, more preferably 1), more preferably an oxygen atom. R a02 、R a03 、R a04 、R a6 and R a7 Examples of the alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group combining these in R a1, R a2 and R a3 include groups similar to those exemplified above. R a02 , R a03 , and R a04 The alkyl group in R, R, and R 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 R and R 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 R and R is preferably an alkenyl group having 2 to 6 carbon atoms, 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 of R, R, R, R, and R preferably has 5 to 12 carbon atoms, more preferably 5 to 10 carbon atoms. R a02 , R a03 , R a04 , R a6 , and R a7 The aromatic hydrocarbon group of R, R, R, R, and R preferably has 6 to 12 carbon atoms, more preferably 6 to 10 carbon atoms. For the group combining an alkyl group and an alicyclic hydrocarbon group, it is preferable that the total carbon number of the combined alkyl group and alicyclic hydrocarbon group is 18 or less. For the group combining an alkyl group and an aromatic hydrocarbon group, it is preferable that the total carbon number of the combined alkyl group and aromatic hydrocarbon group is 18 or less. R a02 , and R a03is preferably an alkyl group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, which may have a halogen atom, and more preferably is a methyl group, an ethyl group, a phenyl group or a naphthyl group, which may have a halogen atom and may have a halogen atom. R a04 is preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 5 to 12 carbon atoms, which may have a halogen atom, and more preferably is a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group, which may have a halogen atom. R a6 and R a7 is preferably an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, which may have a halogen atom, and more preferably is a methyl group, an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group, a phenyl group or a naphthyl group, which may have a halogen atom, and still more preferably is an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group or a phenyl group, which may have a halogen atom. m1 is preferably any integer from 0 to 3, and more preferably is 0 or 1. n1 is preferably any integer from 0 to 3, and more preferably is 0 or 1. n1’ is preferably 0 or 1.

[0107] Examples of the structural unit (a1-0) include a structural unit represented by any of formula (a1-0-1) to formula (a1-0-24) and a structural unit in which the methyl group corresponding to R a01 in the structural unit (a1-0) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group (an alkyl group having a halogen atom) or another alkyl group, and a structural unit represented by any of formula (a1-0-1) to formula (a1-0-10), formula (a1-0-13), formula (a1-0-14), formula (a1-0-19) to formula (a1-0-21) is preferred. JPEG2025105523000098.jpg119159

[0108] Examples of the structural unit (a1-1) include structural units derived from the monomers described in JP-A-2010-204646. Among them, the structural units represented by any of formula (a1-1-1) to formula (a1-1-7) and the methyl group corresponding to R in the structural unit (a1-1) a4 in which is replaced by a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group are preferred, and the structural units represented by any of formula (a1-1-1) to formula (a1-1-4) are more preferred. TIFF2025105523000099.tif39169

[0109] Examples of the structural unit (a1-2) include structural units represented by any of formula (a1-2-1) to formula (a1-2-20) and structural units in which the methyl group corresponding to R in the structural unit (a1-2) a5 is replaced by a hydrogen atom, a halogen atom, a haloalkyl group or another alkyl group, and the structural units represented by any of formula (a1-2-2), formula (a1-2-5), formula (a1-2-6) and formula (a1-2-10) to formula (a1-2-20) are preferred. TIFF2025105523000100.tif91163When the resin contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin. Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 70 mol% or less, even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, still more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin contains the structural unit (a1-0), the content is 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 20 mol% or more, even more preferably 25 mol% or more, yet even more preferably 30 mol% or more, and still even more preferably 35 mol% or more, based on all the structural units of the resin. Also, it is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less. Specifically, it is 5 to 80 mol%, preferably 5 to 75 mol%, and more preferably 10 to 70 mol%. When the resin contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, yet even more preferably 40 mol% or more, and still even more preferably 50 mol% or more, based on all the structural units of the resin. Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, yet even more preferably 70 mol% or less, and still even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, still more preferably 20 to 80 mol%, and even more preferably 20 to 75 mol%.

[0110] Examples of the structural unit derived from the (meth)acrylic monomer having the group (2) also include the structural unit represented by the formula (a1-5) (hereinafter sometimes referred to as "structural unit (a1-5)"). TIFF2025105523000101.tif4760[In the formula (a1-5), all the symbols have the same meanings as described above.]

[0111] R in the formula (a1-5) a8Examples of the halogen atom and the alkyl group which may have a halogen atom include R of formula (a1-0) to formula (a1-2). a01 , R a4 , R a5 include the same ones as those exemplified by them. 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 them, it is preferable that one is -O- and the other is -S-. s1 is preferably 1. s1' is preferably any integer from 0 to 2. Z a1 is preferably a single bond or *-CH2-CO-O-.

[0112] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP-A-2010-61117. Among them, the structural units represented by formula (a1-5-1) to formula (a1-5-4) are preferable, and the structural unit represented by formula (a1-5-1) or formula (a1-5-2) is more preferable. When the TIFF2025105523000102.tif31130 resin contains the structural unit (a1-5), its content is 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, even more preferably 10 mol% or more, still even more preferably 20 mol% or more, and still more preferably 25 mol% or more with respect to all the structural units of the resin. Also, 80 mol% or less is mentioned, preferably 70 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 45 mol% or less, still even more preferably 40 mol% or less, and still more preferably 30 mol% or less. Specifically, 1 to 50 mol% is preferable, 3 to 45 mol% is more preferable, 5 to 40 mol% is still more preferable, and 5 to 30 mol% is still more preferably.

[0113] Examples of the structural unit having the base (1) in the structural unit (a1) include a structural unit represented by the formula (a1-6) (hereinafter sometimes referred to as "structural unit (a1-6)"). TIFF2025105523000103.tif3581 [In the formula (a1-6), all the symbols have the same meanings as described above.]

[0114] R in the formula (a1-6) a61 Examples of the halogen atom and the alkyl group which may have a halogen atom in include R in the formulas (a1-0) to (a1-2) a01 R a4 R a5 and those similar to the exemplified ones. 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 and the like. 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 still more preferably a methyl group or an ethyl group. R a62 R a63 and R a64 Examples of the cyclic hydrocarbon group in include an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group and the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group and the like. 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, a methacryloyloxy group, and the like. R a62 and R a63 The ring formed by their bonding to each other preferably has 3 to 16 carbon atoms, more preferably 3 to 12 carbon atoms. Examples of the ring include an adamantane ring, a cyclohexane ring, and the like. Specifically, when R a62 and R a63 bond to each other to form a ring, examples of -C(R a62 )(R a63 )(R a64 ) include the following groups. * represents the bonding site to the oxygen atom. TIFF2025105523000104.tif33109

[0115] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms in L L a61 and L a62 each independently preferably include a methylene group or an ethylene group. X a61 is preferably a single bond or -CO-O-*, more preferably a single bond. X a62 is preferably a single bond or *-O-L 1 -, more preferably a single bond.

[0116] Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms for Ar include a phenylene group, 1-naphthylene group, 2-naphthylene group, 1-anthrylene group, 9-anthrylene group, biphenylene group, 1-phenanthrylene group, 2-phenanthrylene group, and the like. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, hydroxy group, alkyl group having 1 to 6 carbon atoms, alkoxy group having 1 to 6 carbon atoms, alkoxyalkyl group having 2 to 12 carbon atoms, alkoxyalkoxy group having 2 to 12 carbon atoms, alkylcarbonyl group having 2 to 4 carbon atoms, alkylcarbonyloxy group having 2 to 4 carbon atoms, acryloyloxy group, or methacryloyloxy group. Examples of the halogen atom, alkyl group, alkoxy group, alkoxyalkyl group, alkoxyalkoxy group, alkylcarbonyl group, and alkylcarbonyloxy group include those similar to those exemplified in this specification.

[0117] Examples of the structural unit (a1-6) include structural units represented by Formula (a1-6-1) to Formula (a1-6-44), etc., structural units represented by Formula (a1-6-1) to Formula (a1-6-9) are preferred, structural units represented by Formula (a1-6-1), Formula (a1-6-2), Formula (a1-6-4), Formula (a1-6-5), Formula (a1-6-7), or Formula (a1-6-8) are more preferred, and structural units represented by Formula (a1-6-1) or Formula (a1-6-2) are even more preferred. In the following structural units, the hydrogen atom corresponding to R a61 substituted with a methyl group or the like, and in the following structural units, the methyl group corresponding to R a61 substituted with a hydrogen atom are also included as the structural unit (a1-6). TIFF2025105523000105.tif226161

[0118] When the resin contains the structural unit (a1-6), its content is 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, still more preferably 10 mol% or more, even more preferably 20 mol% or more, still even more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on all the structural units of the resin. Also, it is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 7 to 70 mol%, still even more preferably 7 to 65 mol%, and particularly preferably 10 to 60 mol%.

[0119] In addition, examples of the structural unit (a1) also include the following structural units. TIFF2025105523000106.tif33167

[0120] When the resin contains the structural units represented by the formulas (a1-7-1) to (a1-7-7), its content is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin. Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still 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%, still more preferably 20 to 85 mol%, still even more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol%.

[0121] In addition, examples of the structural unit (a1) also include the following structural units. When the resin contains structural units represented by the formulas (a1-8-1) to (a1-8-3), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin. Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 10 to 60 mol% is preferable, 15 to 55 mol% is more preferable, 20 to 50 mol% is still more preferable, 20 to 45 mol% is even more preferable, and 20 to 40 mol% is particularly preferable.

[0122] 〈Structural unit(s)〉 The structural unit(s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer(s)"). As the monomer that leads to the structural unit(s), a monomer having no acid-labile group known in the resist field can be used. As the structural unit(s), it is preferable to have a hydroxy group, a carboxy group or a lactone ring. By using a resin containing a structural unit having a hydroxy group or a carboxy group and not having an acid-labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and not having an acid-labile group (hereinafter sometimes referred to as "structural unit (a3)") in the resist composition of the present invention, the resolution of the resist pattern and the adhesion to the substrate can be improved. In addition to the above-described structural units, the structural unit(s) includes a structural unit having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"), a structural unit having a sultone structure (hereinafter sometimes referred to as "structural unit (a6)"), or a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)"), and the like.

[0123] 〈Structural unit (a2)〉 The structural unit (a2) is a structural unit represented by the formula (a2) excluding the structural unit of the structural unit (a2-A), and has an alcoholic hydroxy, phenolic hydroxy group or phenolic carboxy group. TIFF2025105523000108.tif4094[In the 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 may be replaced by -O-, -CO- or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. L a21 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. L a22represents a linear hydrocarbon group having 1 to 12 carbon atoms which may have a single bond or a fluorine atom, and -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-. na2 represents any integer from 1 to 4.

[0124] R a2 and A a21 are the same as those exemplified for R a2 and A a21 in formula (a2-A). The hydrocarbon group in L a21 is a (na2 + 1)-valent hydrocarbon group, and examples thereof include linear hydrocarbon groups, alicyclic hydrocarbon groups such as monocyclic or polycyclic (including spiro rings, condensed rings, bridged rings, etc.) alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and groups formed by combining two or more of these groups (for example, hydrocarbon groups formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a linear hydrocarbon group) may also be used. L a21 Examples of the linear hydrocarbon group of include divalent to pentavalent linear hydrocarbon groups such as alkanediyl groups, alkanetriyl groups, alkanetetrayl groups, and alkanepentayl groups. L a21 Examples of the alkanediyl group of a21 include the same alkanediyl groups as A L a21 Examples of the alkanetriyl group of include methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decanetriyl group, undecanetriyl group, dodecanetriyl group, tridecanetriyl group, tetradecanetriyl group, pentadecanetriyl group, hexadecanetriyl group, and 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 alkanepentayl group include a methanepentayl group, an ethanepentayl group, a propanepentayl group, a butanepentayl group, a pentanepentayl group, and a hexanepentayl group. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. L a21 The number of carbon atoms of the chain hydrocarbon group of L is preferably 1 to 18, more preferably 1 to 12, still more preferably 1 to 10, even more preferably 1 to 9, still even more preferably 1 to 8, still more preferably 1 to 6, still even more preferably 1 to 5, and particularly preferably 1 to 4. L a21 Examples of the monocyclic and polycyclic divalent alicyclic hydrocarbon groups in L include the following alicyclic hydrocarbon groups. The bonding site can be at any position. TIFF2025105523000109.tif46168For example, monocyclic alicyclic hydrocarbon groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, a cyclooctane-1,5-diyl group, a cyclopropanetriyl group, a cyclobutanetriyl group, a cyclopentanetriyl group, a cyclohexanetriyl group, a cycloheptanetriyl group, a cyclooctanetriyl group, a cyclodecanetriyl group, a cyclopropanetetrayl group, a cyclobutanetetrayl group, a cyclopentanetetrayl group, a cyclohexanetetrayl group, a cycloheptanetetrayl group, a cyclooctanetetrayl group, and a cyclodecanetetrayl group, and Examples of the polycyclic alicyclic hydrocarbon group 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]octanediy group, norbornanetril group, adamantanetril group, decahydronaphthalenetril group, bicyclo[3.3.0]octanetril group, norbornanetetrayl group, adamantanetetrayl group, decahydronaphthalenetetrayl group, bicyclo[3.3.0]octanetetrayl group, etc. The number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 20, more preferably 3 to 18, still more preferably 3 to 16, even more preferably 3 to 12, still even more preferably 6 to 12, and particularly preferably 6 to 10. L a21 Examples of the divalent aromatic hydrocarbon group in L include phenylene group, naphthylene group, anthrylene group, biphenylene group, phenanthrylene group, benzenetriyl group, naphthalenetriyl group, anthracenetriyl group, biphenylenetriyl group, phenanthrenetriyl group, benzenetetrayl group, naphthalenetetrayl group, anthracenetetrayl group, biphenylenetetrayl group, phenanthrenetetrayl group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 6 to 20, more preferably 6 to 18, still more preferably 6 to 14, even more preferably 6 to 12, and still even more preferably 6 to 10. Examples of the group formed by combining two or more of them include a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group, a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group, a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group, a group formed by combining an alicyclic hydrocarbon group, a chain hydrocarbon group and an aromatic hydrocarbon group, etc. In the combination, the alicyclic hydrocarbon group, the aromatic hydrocarbon group and the chain hydrocarbon group may each be combined with two or more of them. Also, any group may be bonded to A a21 and L a22 if necessary. L a21As the alkanediyl group, it may be replaced by -O- or -CO-, and L a21 When the alkanediyl group of a21 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-, and * represents the bonding site with X a2 .) is preferable. Examples of the group in which -CH2- contained in the hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group, a carboxy group, a thiol group, an amino group (, a carboxy group, an oxy group, a carbonyl group (, a thio group, a sulfonyl group (, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an alkylcarbonyl group, an alkylamino group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, an alkanediyloxy group, an alkanediyloxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, an alkanediylamino group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, an aromatic hydrocarbon group - carbonyloxy group, an aromatic hydrocarbon group - carbonyl group, an aromatic hydrocarbon group - oxy group, a group formed by combining two or more of these groups, etc. Further, groups in which one or more hydrogen atoms of these groups are replaced by a bonding site, etc. are also included. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits.

[0125] In addition, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group, the aromatic hydrocarbon group and the group combining the alicyclic hydrocarbon group and the aromatic hydrocarbon group is replaced by -O-, -S-, -CO-, -SO-, -NR 11 - or -SO2- include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. L a21The hydrocarbon group in may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), an acryloyloxy group, a methacryloyloxy group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. L a21 By having a halogen atom as a substituent, the hydrocarbon group in can substantially have a substituent such as a haloalkyl group. Examples of the haloalkyl group include a chloromethyl group, a bromomethyl group, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a perfluorobutyl group, etc. A haloalkyl group having 1 to 4 carbon atoms is preferred, and a haloalkyl group having 1 to 3 carbon atoms is more preferred. L a21 By including a branched structure, the hydrocarbon group of enables to substantially have a substituent such as an alkyl group. a21 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, etc. The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. L a21 Due to the group in which -CH2- contained in the hydrocarbon group of is replaced by -O- or -CO-, can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, etc. a21 Examples of the substituent include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, etc. L a21Examples of the substituent that the hydrocarbon group may have include a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-). A halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 10 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-) are more preferable. 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 are even more preferable. 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 are even more preferable. A fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group are even more preferable. L a21 is a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 20 carbon atoms (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO-, -SO-, -NR 11 -, or -SO2-), or a group formed by combining an optionally substituted chain hydrocarbon group having 1 to 8 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 20 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2-, -SO-, -NR 11 -, or -CO-). Preferably, it is 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-), 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 11-or may be replaced by -SO2-. ) Or a group formed by combining an optionally substituted linear hydrocarbon group having 1 to 6 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (provided that -CH2- contained in the linear hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the cyclic hydrocarbon group may be -O-, -S-, -SO2-, -SO-, -NR 11 -or may be replaced by -CO-. ) is more preferably.

[0126] L a22 Examples of the linear hydrocarbon group having 1 to 12 carbon atoms of L include 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, dodecane-1,12-diyl group and other linear alkanediyl groups, ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-dimethylpropane-1,3-diyl group, pentane-2,4-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group and the like. The number of carbon atoms of the linear hydrocarbon group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. L a22 The fluorine atom that L has may be one or two or more. L a22 -CH2- contained in the linear hydrocarbon group of L may be replaced by -O- or -CO-, and these replaced groups are, within the range allowed by the upper limit of the number of carbon atoms, the same as those exemplified by L a21 and the like. na2 is preferably any integer from 1 to 4, and more preferably any integer from 1 to 3. La21 When the structural unit (a2) is a single bond or a chain hydrocarbon group, examples of the structural unit (a2) include the following structural units. Among the following groups, the structural unit in which the methyl group corresponding to R a2 is replaced by a hydrogen atom or the like is also a preferred structural unit of the structural unit (a2) in the same manner as the following structural units. TIFF2025105523000110.tif68168

[0127] When producing a resist pattern from the resist composition of the present invention, when using a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) as an exposure light source, as the structural unit (a2), a structural unit (a2) having a phenolic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-A). Further, when using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), a structural unit (a2) having an alcoholic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-B), the structural unit (a2-C), and the structural unit (a2-D) described later. The structural unit (a2) may be included alone or in two or more kinds.

[0128] In the structural unit (a2), L a21 is a cyclic hydrocarbon group, and examples of the structural unit having an alcoholic hydroxy group or a carboxy group include the structural unit represented by the formula (a2-B) (hereinafter sometimes referred to as the "structural unit (a2-B)"), the structural unit represented by the formula (a2-C) (hereinafter sometimes referred to as the "structural unit (a2-C)"), or the structural unit represented by the formula (a2-D) (hereinafter sometimes referred to as the "structural unit (a2-D)"). TIFF2025105523000111.tif45100[In the formula (a2-B) and the formula (a2-C), R a2 represents the same meaning as in the formula (a2). R a27 represents the same meaning as in the formula (a2-A). L a25 is -O- or *-O-(CH2) k2-CO-O- represents, and k2 represents any integer from 1 to 7. * represents the bonding position with -CO-. X a2 represents a single bond or -CO-. R a25 and R a26 each independently represent a hydrogen atom, a methyl group, or a hydroxy group. nB2 represents any integer from 1 to 5. When nB2 is 2 or more, the plurality of X a2 may be the same as or different from each other. nB22 represents any integer from 0 to 8. When nB22 is 2 or more, the plurality of R a27 may be the same as or different from each other. nC22 represents any integer from 0 to 10. When nC22 is 2 or more, the plurality of R a27 may be the same as or different from each other. L a25 is preferably -O-, -O-(CH2) f1 -CO-O- (wherein f1 represents any integer from 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, 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 ethoxy methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nB2 is preferably 1, 2, 3, or 4, more preferably 1, 2, or 3, and even more preferably 1 or 2. nB22 is preferably an integer of 0 to 3, more preferably 0, 1 or 2, and further preferably 0 or 1. nC22 is preferably an integer of 0 to 6, more preferably an integer of 0 to 3, and further preferably 0 or 1.

[0129] Examples of the structural unit (a2-B) and the structural unit (a2-C) include structural units derived from monomers described in JP-A-2010-204646, the following structural units, and R a2 In particular, structural units represented by any one of formulae (a2-B-1) to (a2-B-5) and formulae (a2-C-1) to (a2-C-9) are preferred. TIFF2025105523000112.tif80164 When the resin contains the structural unit (a2-B) or formula (a2-C), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on the total structural units of the resin. Also, 45 mol% or less is mentioned, preferably 40 mol% or less, more preferably 35 mol% or less, even more preferably 20 mol% or less, and even more preferably 10 mol% or less. Specifically, 1 to 45 mol% is mentioned, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol% or 2 to 20 mol%, and even more preferably 1 to 10 mol% or 2 to 10 mol%.

[0130] TIFF2025105523000113.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 a24represents 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 any integer from 1 to 5. When nD2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. nD22 represents any integer from 0 to 4. When nD22 is 2 or more, the plurality of Rs a27 may be the same as or different from each other. ] R a21 and R a22 are preferably a trifluoromethyl group. L a24 Examples of the alkanediyl group of include a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, and the like. 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 the parentheses is bonded to the para position. nD22 is preferably any integer from 0 to 3, more preferably any integer from 0 to 2, even more preferably 0 or 1, and even more preferably 0.

[0131] 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)"). TIFF2025105523000114.tif51107[In formula (a2-D1), all the symbols represent the same meanings as described above.] In formula (a2-D1), R a2 is preferably a hydrogen atom or a methyl group. A a21 is preferably a single bond.

[0132] Examples of the structural unit (a2-D) include the structural units described below. TIFF2025105523000115.tif62167

[0133] In the structural units represented by formulas (a2-D-1) to (a2-D-8), the hydrogen atom corresponding to R a2 replaced by a methyl group or the like, and in the structural units represented by formulas (a2-D-9) to (a2-D-16), the methyl group corresponding to R a2 replaced by a hydrogen atom or the like can also be cited as specific examples of the structural unit (a2-D). Among them, the structural units represented by formulas (a2-D-1) to (a2-D-8) are preferable, the structural units represented by formulas (a2-D-1) to (a2-D-4) are more preferable, and the structural unit represented by formula (a2-D-1) is even more preferable.

[0134] When the resin contains the structural unit (a2-D), its content is preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more with respect to all the structural units of the resin. Also, it is preferably 80 mol% or less, more preferably 75 mol% or less, even more preferably 70 mol% or less, and still 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 still more preferably 10 to 65 mol%.

[0135] 〈Structural unit (a3)〉 The lactone ring of the structural unit (a3) ​​may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or may be a condensed ring of a monocyclic lactone ring and another ring. Preferred examples include a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, a structural unit represented by the following formula (a3-2)).

[0136] The structural unit (a3) ​​is preferably a structural unit represented by formula (a3-1), (a3-2), (a3-3) or (a3-4). One of these may be contained alone, or two or more of them may be contained. TIFF2025105523000116.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 any of 1 to 7). L a7 , -O-, *-OL a8 -O-, *-OL a8 -CO-O-, *-OL a8 -CO-OL a9 -CO-O- or *-OL a8 -O-CO-L a9 Represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * indicates the bonding site with the carbonyl group. R a18 , R a19 , R a20 and R a24 each independently represents 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 any integer from 0 to 5. q1 represents any integer from 0 to 3. r1 represents any integer from 0 to 3. w1 represents any integer from 0 to 8. When p1, q1, r1 and / or w1 is 2 or more, a plurality of R a21 、R a22 、R a23 and / or R a25 may be the same as or different from each other.

[0137] R a21 、R a22 、R a23 and R a25 Examples of the aliphatic hydrocarbon group in include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group and tert-butyl group. R a18 、R a19 、R a20 and R a24 Examples of the halogen atom and the alkyl group which may have a halogen atom in include the same as those exemplified by R of formula (a1-0) to formula (a1-2). a01 、R a4 、R a5 and the like. L a8 and L a9 Examples of the alkanediyl group in include 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, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group and 2-methylbutane-1,4-diyl group and the like. L a4 ~L a6is, independently of each other, preferably -O- or, *-O-(CH2) k3 -CO-O- wherein k3 is an integer of 1 to 4, more preferably -O- and, *-O-CH2-CO-O-, even more preferably an oxygen atom. L a7 is preferably -O- or *-O-L a8 -CO-O-, more preferably -O-, -O-CH2-CO-O- or -O-C2H4-CO-O-. R a18 R a19 R a20 and R a24 are 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, 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 are each independently preferably an integer of 0 to 2, more preferably 0 or 1. w1 is preferably an integer of 0 to 2, more preferably 0 or 1. In particular, formula (a3-4) is preferably formula (a3-4)'. TIFF2025105523000117.tif4051 (wherein R a24 and L a7 have the same meanings as described above.)

[0138] Examples of the structural unit (a3) include structural units derived from the monomers described in JP-A-2010-204646, the monomers described in JP-A-2000-122294, and the monomers described in JP-A-2012-41274. Examples of the structural unit (a3) include structural units represented by any of formula (a3-1-1), formula (a3-1-2), formula (a3-2-1), formula (a3-2-2), formula (a3-3-1), formula (a3-3-2), and formula (a3-4-1) to formula (a3-4-12), and in the said structural units, R in formula (a3-1) to formula (a3-4) a18 , R a19 , R a20 and R a24 The structural unit in which the methyl group corresponding to is replaced by a hydrogen atom is preferred. When the resin contains the structural unit (a3), the total content thereof is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, still more preferably 10 mol% or more, based on all the structural units of the resin. Further, it is 70 mol% or less, preferably 65 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 40 mol% or less, still 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 1 to 70 mol%, preferably 1 to 65 mol%, more preferably 1 to 60 mol%, and still more preferably 3 to 60 mol%. Also, the content rate of structural unit (a3-1), structural unit (a3-2), structural unit (a3-3), or structural unit (a3-4) is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, and even more preferably 10 mol% or more, respectively, based on all the structural units of resin (A). Also, it is preferably 60 mol% or less, more preferably 55 mol% or less, still more preferably 50 mol% or less, even more preferably 40 mol% or less, still even more preferably 30 mol% or less, even more preferably 25 mol% or less, and even more preferably 20 mol% or less. Specifically, 1 to 60 mol% is preferable, 3 to 50 mol% is more preferable, and 5 to 50 mol% is still more preferable.

[0139] 〈Structural unit (a4)〉 The structural unit represented by formula (a4) is shown below. TIFF2025105523000119.tif2770[In formula (a4), R 41 represents a hydrogen atom or a methyl group. R 42 represents an aliphatic hydrocarbon group having a halogen atom with 1 to 48 carbon atoms, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O- or -CO-.

[0140] R 42 The aliphatic hydrocarbon group represented by is a linear or branched chain hydrocarbon group, a monocyclic or polycyclic alicyclic hydrocarbon group, and a group formed by combining these, etc. Examples of the chain hydrocarbon group include linear alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentadecyl group, hexadecyl group, heptadecyl group, and octadecyl group, and branched alkyl groups such as isopropyl group and isobutyl group. 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 group (* represents a bonding site). Examples of the group formed by the combination of TIFF2025105523000120.tif10146 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, -alkanediyl group-alicyclic hydrocarbon group-alkyl group, and the like. 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, and a hexane-1,6-diyl group; and branched alkanediyl groups such as a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a 1-methylbutane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. The terminal of the branched alkanediyl group may be a methyl group. R 42 Examples of the halogen atom included in the aliphatic hydrocarbon group contained in 42 include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. R 42 Examples of the group in which -CH2- of the aliphatic hydrocarbon group contained in 42 is replaced by -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 alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, a cycloalkoxy group, a cycloalkylalkoxy group, and groups formed by combining two or more of these groups. These replaced groups include those similar to the groups exemplified in this specification as long as the upper limit of the number of carbon atoms permits.

[0141] As the structural unit (a4), R 42 is preferably an aliphatic hydrocarbon group having a fluorine atom, and R 42 Examples of the structural unit (a4) in which is an aliphatic hydrocarbon group having a fluorine atom include a structural unit represented by the formula (a4-1) (hereinafter, may be referred to as "structural unit (a4-1)"), a structural unit represented by the formula (a4-2) (hereinafter, may be referred to as "structural unit (a4-2)"), a structural unit represented by the formula (a4-3) (hereinafter, may be referred to as "structural unit (a4-3)"), and a structural unit represented by the formula (a4-A) (hereinafter, may be referred to as "structural unit (a4-A)"). The structural unit represented by the formula (a4-1) is the structural unit shown below. TIFF2025105523000121.tif3092 [In the 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 an alkanediyl group having 1 to 8 carbon atoms having a fluorine atom or a cycloalkanediyl group having 3 to 12 carbon atoms having a fluorine atom. R 42f represents a hydrogen atom or a fluorine atom.]

[0142] Examples of the alkanediyl group in L 41 include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a butane-1,4-diyl group, and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. The terminal of the branched alkanediyl group may be a methyl group. L 42fExamples of the alkanediyl group having a fluorine atom in [L] include linear alkanediyl groups having a fluorine atom such as a methylene group having a fluorine atom, an ethylene group having a fluorine atom, a propane-1,3-diyl group having a fluorine atom, a butane-1,4-diyl group having a fluorine atom, a pentane-1,5-diyl group having a fluorine atom, a hexane-1,6-diyl group having a fluorine atom, a heptane-1,7-diyl group having a fluorine atom, and an octane-1,8-diyl group having a fluorine atom; branched alkanediyl groups having a fluorine atom such as an ethane-1,1-diyl group having a fluorine atom, a propane-1,1-diyl group having a fluorine atom, a propane-1,2-diyl group having a fluorine atom, a propane-2,2-diyl group having a fluorine atom, a pentane-2,4-diyl group having a fluorine atom, a 2-methylpropane-1,3-diyl group having a fluorine atom, a 2-methylpropane-1,2-diyl group having a fluorine atom, a pentane-1,4-diyl group having a fluorine atom, and a 2-methylbutane-1,4-diyl group having a fluorine atom. The terminal of the branched alkanediyl group may be a methyl group which may have a fluorine atom. L 42f Examples of the cycloalkanediyl group having a fluorine atom in [L] include monocyclic cycloalkanediyl groups 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, and a cyclooctane-1,5-diyl group having a fluorine atom, and polycyclic cycloalkanediyl groups having a fluorine atom such as 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 of the alkanediyl group and the cycloalkanediyl group having a fluorine atom in [L] may be 1 or more, and is preferably 2 or more. L42f The alkanediyl group and the cycloalkanediyl group having a fluorine atom in are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0143] L 42f Examples of the perfluoroalkanediyl group in 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, a perfluorohexane-1,6-diyl group, a perfluorohexane-2,2-diyl group, a perfluorohexane-3,3-diyl group, a perfluoroheptane-1,7-diyl group, a perfluoroheptane-2,2-diyl group, a perfluoroheptane-3,4-diyl group, a perfluoroheptane-4,4-diyl group, a perfluorooctane-1,8-diyl group, a perfluorooctane-2,2-diyl group, a perfluorooctane-3,3-diyl group, a perfluorooctane-4,4-diyl group, and the like. L 42f Examples of the perfluorocycloalkanediyl group in include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, a perfluoroadamantanediyl group, and the like.

[0144] 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 still more preferably a single bond or a methylene group. L 42fis preferably a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and even more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0145] Examples of the structural unit (a4-1) include the structural units shown below and the structural units in the structural unit (a4-1) in the following structural units where the methyl group corresponding to R 41 is replaced by a hydrogen atom. The structural unit represented by the formula (a4-2) is the structural unit shown below. TIFF2025105523000123.tif33101 [In the 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 by -O- or -CO-. R 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, at least one of L 43f and R 43f has a fluorine atom, and the upper limit of the total number of carbon atoms of L 43f and R 43f is 21.

[0146] Examples of the aliphatic hydrocarbon group in L 43f and R 43f include linear or branched chain hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these. Examples of the aliphatic hydrocarbon group in L 43f and R 43f are, as long as the upper limit of the total number of carbon atoms of L 43f and R 43f allows, R in the formula (a4)42 Examples of the aliphatic hydrocarbon group of 42 include the same groups as the exemplified aliphatic hydrocarbon groups.

[0147] L 43f As the aliphatic hydrocarbon group of 43f , an alkanediyl group having 1 to 6 carbon atoms or a group represented by the formula (L43f-1) is preferable. TIFF2025105523000124.tif14120 [In the formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represent a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. L 47f represents a single bond or a divalent aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. X 46f and X 47f each independently represent -O-, -CO-, -CO-O- or -O-CO-. However, the total number of carbon atoms of L 45f , L 46f , L 47f , X 46f and X 47f is 7 or less. * and ** are bonding sites, and ** is the bonding site with -O-CO-R 43f .

[0148] Examples of the divalent aliphatic hydrocarbon group represented by L 45f , L 46f and L 47f in the group represented by the formula (L43f-1) 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 and a divalent alicyclic hydrocarbon group. Specifically, a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, etc. are included. s is preferably 0.

[0149] Examples of the group represented by formula (L43f-1) include the following groups. In the following examples, * and ** each represent a bonding site, and ** is the bonding site with -O-CO-R 43f TIFF2025105523000125.tif47140

[0150] 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 the structural units represented by formula (a4-2A) or (formula a4-2B). TIFF2025105523000126.tif41157[In formula (a4-2A) and formula (a4-2B), R 41 and L 43f represent the same as those in formula (a4-2). R 43fA represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms and having 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 by -O- or -CO-. X 43 represents **-O-CO- or **-CO-O-, and ** represents the bonding site with A 43f R 43fB represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, in formula (a4-2A), the total number of carbon atoms of L 43f and R 43fA is 21 or less, and in formula (a4-2B), the total number of carbon atoms of L 43f , A 43f , X 43 and R 43fB is 21 or less, and at least one of A 43f and R 43fB has at least one fluorine atom.​​ R 43fA The aliphatic hydrocarbon group of R, as long as the upper limit of the number of carbon atoms permits, is an aliphatic hydrocarbon group similar to the aliphatic hydrocarbon group exemplified by R 42 and includes the same aliphatic hydrocarbon groups as those exemplified for the aliphatic hydrocarbon groups of R R 43fA is preferably an alkyl group having 1 to 13 carbon atoms and having fluorine atoms, a cycloalkyl group having 3 to 12 carbon atoms and having fluorine atoms, or a group combining them, *-(CF2) n43f -R 42’ (* represents the bonding site with the carbonyl group. n43f represents any integer from 1 to 6. R 42’ represents a hydrogen atom or a fluorine atom.), or more preferably a perfluorocycloalkyl group having 3 to 12 carbon atoms A 43f and the aliphatic hydrocarbon group of R, as long as the upper limit of the number of carbon atoms permits, is an aliphatic hydrocarbon group similar to the aliphatic hydrocarbon group exemplified by R in formula (a4) 43fB and includes the same aliphatic hydrocarbon groups as those exemplified for the aliphatic hydrocarbon groups of R 42 in formula (a4) A 43f is preferably a divalent chain hydrocarbon group which may have fluorine atoms, a divalent alicyclic hydrocarbon group, or a group combining them, more preferably a divalent chain hydrocarbon group having fluorine atoms, and even more preferably a fluoroalkanediyl group having 1 to 6 carbon atoms R 43fBThe aliphatic hydrocarbon group which may have a fluorine atom is preferably a chain hydrocarbon group, an alicyclic hydrocarbon group or a combination thereof which may have a fluorine atom, more preferably an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms or a combination thereof which may have a fluorine atom, and trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, pentyl group, hexyl group, perfluorohexyl group, heptyl group, perfluoroheptyl group, octyl group, perfluorooctyl group and other alkyl fluoride groups, cyclopropylmethyl group, cyclopropyl group, cyclobutylmethyl group, cyclopentyl group, cyclohexyl group, perfluorocyclohexyl group, adamantyl group, adamantylmethyl group, adamantyldimethyl group, norbornyl group, norbornylmethyl group, perfluoroadamantyl group, perfluoroadamantylmethyl group and the like are more preferable.

[0151] In formula (a4-2B), *-A f43 -X 43 -R f43B An example of the structure that the group represented by can take is the following structure (* is the bonding site with the carbonyl group). TIFF2025105523000127.tif14170

[0152] As the structural unit represented by formula (a4-2A), there may be mentioned the following structural units and the structural units in which the methyl group corresponding to R in the structural unit represented by formula (a4-2A) below is replaced by a hydrogen atom. 41 TIFF2025105523000128.tif99167

[0153] Examples of the structural unit represented by the formula (a4-2B) include the following structural units and structural units in which the methyl group corresponding to R in the following structural units is replaced with a hydrogen atom. 41 Examples include structural units in which the methyl group corresponding to R in the following structural units is replaced with a hydrogen atom. TIFF2025105523000129.tif111163

[0154] Examples of the structural unit (a4) also include a structural unit represented by the formula (a4-3). TIFF2025105523000130.tif3589 [In the 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 have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-. R 44f 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, at least one of 44f L and 44f R has a fluorine atom, and the upper limit of the total number of carbon atoms of 44f L and 44f R is 21.

[0155] Examples of the aliphatic hydrocarbon group in 44f L and 44f R include linear or branched chain aliphatic hydrocarbon groups, monocyclic or polycyclic alicyclic hydrocarbon groups, and groups formed by combining these. Examples of the aliphatic hydrocarbon group in 44f L and 44f R are, as long as the upper limit of the total number of carbon atoms of 44f L and 44f R permits, the same groups as the aliphatic hydrocarbon groups exemplified as the aliphatic hydrocarbon group of R in the formula (a4). 42 Examples of the aliphatic hydrocarbon group of R in the formula (a4) include the same groups as the aliphatic hydrocarbon groups exemplified above. L 44fis preferably an alkanediyl group having 1 to 14 carbon atoms (wherein -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 - (where j1 to j5 each independently represent an integer of 1 to 6). More preferably, it is an alkanediyl group having 1 to 4 carbon atoms (where one -CH2- contained in the alkanediyl group may be replaced by -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced by -CO-O- or -O-CO-). R 44f is preferably an aliphatic hydrocarbon group having 1 to 10 carbon atoms having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, an alicyclic hydrocarbon group having 3 to 10 carbon atoms having a fluorine atom, or a group combining them, still more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms having a fluorine atom.

[0156] Examples of the structural unit represented by the formula (a4-3) include structural units represented by the following structural units and the following formulas, in which the methyl group corresponding to R in the structural unit (a4-3) is replaced by a hydrogen atom. 41 TIFF2025105523000131.tif85170

[0157] Examples of the structural unit (a4) also include a structural unit represented by the formula (a4-A). TIFF2025105523000132.tif3686 [In the formula (a4-A), all symbols represent the same meaning as described above.]

[0158] R 1 ​The alkyl group having 1 to 6 carbon atoms in [X] includes a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R 1 Examples of the halogen atom in [X] include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 1 Examples of the alkyl group having 1 to 6 carbon atoms and having a halogen atom in [X] include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a dichloromethyl group, a triiodomethyl group, a diiodomethyl group, a tribromomethyl group, and a dibromomethyl group. R 1 R is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0159] L 1 Examples of the aliphatic hydrocarbon group in [X] include a chain hydrocarbon group, a monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.) alicyclic hydrocarbon group, and a group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group) may also be used. Examples of the chain hydrocarbon group include a divalent to pentavalent chain hydrocarbon group such as an alkanediyl group, an alkanetriyl group, an alkanetetrayl group, and an alkanpentayl group. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-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, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. Examples also include groups in which one or more hydrogen atoms of the above-described groups are replaced with a bonding site. The number of carbon atoms in the chain hydrocarbon group is preferably from 1 to 18, more preferably from 1 to 12, still more preferably from 1 to 10, even more preferably from 1 to 9, still even more preferably from 1 to 8, still more preferably from 1 to 6, still even more preferably from 1 to 5, and particularly preferably from 1 to 4.

[0160] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups. The bonding site can be at any position. TIFF2025105523000133.tif45164 For example, alicyclic hydrocarbon groups such as cycloalkanediyl groups. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group, and Polycyclic alicyclic hydrocarbon groups such as spiro rings having a cycloalkanediyl group such as a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, a decahydronaphthalenediyl group, a bicyclo[3.3.0]octanediyl group, a spirocyclohexane-1,2'-cyclopentane-diyl group, a spiroadamantane-2,3'-cyclopentane-diyl group, etc., or a cycloalkanediyl group spiro-bonded to each of a norbornyl group or an adamantyl group, etc. are exemplified. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 20, more preferably 3 to 18, still more preferably 3 to 16, and even more preferably 3 to 12.

[0161] Examples of the group combined with two or more types include a group combining 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 respectively. Also, any of the groups may be bonded to X 11 in any manner. Examples of the group 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-), a group in which a chain hydrocarbon group is bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-), 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-), a group in which a chain hydrocarbon group and an alicyclic hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which an alicyclic hydrocarbon group, a chain hydrocarbon group, and an alicyclic hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which a chain hydrocarbon group, an alicyclic hydrocarbon group, and a chain hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-), etc. * represents the bonding site to X 11 in each case.

[0162] L 1 In the aliphatic hydrocarbon group having 1 to 28 carbon atoms of L, -CH2- may be replaced by -O-, -S-, -SO2- or -CO-. L 1 When -CH2- contained in the aliphatic hydrocarbon group of L is replaced by -O-, -S-, -SO2- or -CO-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the aliphatic hydrocarbon group. Examples of the group in which -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-, -S-, -SO2- 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 alkanedioxy group, an alkanedioxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, and a group formed by combining two or more of these groups. These replaced groups include those similar to the groups exemplified herein as long as the upper limit of the number of carbon atoms permits. Also included are groups in which one or more hydrogen atoms of the above-described groups are replaced by a bonding site. Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include those similar to the groups exemplified herein as long as the upper limit of the number of carbon atoms permits.

[0163] L 1 The aliphatic hydrocarbon group in L may have one or more substituents. Examples of the substituent include 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 (in the alkyl group or the alicyclic hydrocarbon group, -CH2- may be replaced by -O- or -CO-). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. The C1-C4 haloalkyl group includes a C1-C4 fluoroalkyl group, a C1-C4 chloroalkyl group, a C1-C4 bromoalkyl group, a C1-C4 iodoalkyl group, etc. Examples of the haloalkyl group include a C1-C4 perfluoroalkyl group (such as a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, etc.), 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, an iodomethyl group, etc. The number of carbon atoms in the haloalkyl group is preferably 1-3, more preferably 1 or 2. Examples of the C1-C12 alkyl group 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 1-9, more preferably 1-6, still more preferably 1-4, and even more preferably 1-3. When -CH2- contained in the alkyl group is replaced by -O- or -CO-, the total number of carbon atoms before replacement is defined as the total number of carbon atoms of the alkyl group. Examples of the replaced group include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxycarbonyloxy group, etc. L 1Examples of the substituent that the aliphatic hydrocarbon group in [compound name] may have include 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 (wherein -CH2- contained in the alkyl group or the alicyclic hydrocarbon group may be replaced by -O- or -CO-). Preferred are 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 (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-). More preferred are a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group. L 1 is R 3When it does not form an alkyl fluoride group and an alicyclic hydrocarbon group, it may have a substituent and a chain hydrocarbon group having 1 to 12 carbon atoms (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), or a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), preferably a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -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 chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), more preferably a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent, a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), or a group formed by combining an alicyclic hydrocarbon group having 5 to 12 carbon atoms, a chain hydrocarbon group having 1 to 6 carbon atoms, and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), even more preferably.

[0164] R 2Examples of the alkyl fluoride group having 1 to 8 carbon atoms include difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1-(trifluoromethyl)-1,2,2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis(trifluoro)methyl-2,2,2-trifluoroethyl group, 2-(perfluoropropyl)ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl group, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group, 2-(perfluorobutyl)ethyl group, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group, perfluorohexyl group, perfluoroheptyl group, and perfluorooctyl group. The number of carbon atoms of the alkyl fluoride group is preferably 1 to 6, more preferably 1 to 5, still more preferably 1 to 4, and even more preferably 1 to 3. R 3 When the alkyl fluoride group having 1 to 6 carbon atoms is R 2 the alkyl fluoride groups having 1 to 6 carbon atoms exemplified in the examples of the alkyl fluoride group of R R 2 is preferably an alkyl fluoride group having 1 to 6 carbon atoms, more preferably an alkyl fluoride 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 when R 3 is an alkyl fluoride group having 1 to 6 carbon atoms. R2 When R 3 is a hydrogen atom, it is preferably an alkyl fluoride group having 1 to 6 carbon atoms, more preferably an alkyl fluoride group having 1 to 5 carbon atoms, and still more preferably an alkyl fluoride group having 3 to 5 carbon atoms. R 3 is bonded to L 1 to form an alicyclic hydrocarbon group having 3 to 6 carbon atoms, R 3 is bonded to L 1 Examples of the group formed by the combination include groups represented by the following formulas. In the following formulas, * and ** represent bonding sites, and the two ** represent that one represents the bonding site with a hydroxy group and the other represents the bonding site with R 2 and L 1A is a part of the hydrocarbon group of L 1 and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. TIFF2025105523000134.tif22138R 3 is preferably a hydrogen atom or an alkyl fluoride group having 1 to 3 carbon atoms. mi is preferably any integer from 1 to 3, more preferably 1 or 2, and still more preferably 1.

[0165] Examples of the structural unit (a4-A) include the following structural units and the like. In the following structural units, structural units in which the methyl group corresponding to R 1 is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or an alkyl group other than a methyl group, and structural units in which the hydrogen atom corresponding to R 1 is replaced with a halogen atom, a haloalkyl group or an alkyl group can also be cited as specific examples of the structural unit (a4-A). TIFF2025105523000135.tif192167

[0166] When the resin has the structural unit (a4), its content is preferably 1 to 97 mol%, more preferably 2 to 95 mol%, and still more preferably 3 to 90 mol% based on all the structural units of the resin.

[0167] <Structural unit (a5)> Examples of the non-detachable hydrocarbon group included in the structural unit (a5) include groups having a linear, branched or cyclic hydrocarbon group. Among them, the structural unit (a5) preferably has a group having an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by the formula (a5-1). TIFF2025105523000136.tif3971[In the 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 the hydrogen atoms contained in the alicyclic hydrocarbon group may be substituted with aliphatic hydrocarbon groups 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 by -O- or -CO-.]

[0168] R 52 The alicyclic hydrocarbon group in R may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group and a norbornyl group. Examples of the aliphatic hydrocarbon group having 1 to 8 carbon atoms include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group and a 2-ethylhexyl group. Examples of the alicyclic hydrocarbon group having a substituent include a 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group or a cyclohexyl group. L 55Examples of the divalent saturated hydrocarbon group include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, preferably a divalent chain saturated hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include alkanediyl groups such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, and a pentanediyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic divalent alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as a cyclopentanediyl group and a cyclohexanediyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include an adamantanediyl group and a norbornanediyl group.

[0169] L 55 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced with -O- or -CO- include the groups represented by formula (L1-1) to formula (L1-4). In the following formulas, * and ** each represent a bonding site, and * represents a bonding site with an oxygen atom. TIFF2025105523000137.tif18165[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents a bonding site with L x1 .). 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, the total number of carbon atoms of L x1 and L x2 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, the total number of carbon atoms of L x3 and L x4 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 represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the total number of carbon atoms of L x5 , L x6 and L x7 is 15 or less. In formula (L1-4), L x8 and L x9 each represent 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, the total number of carbon atoms of L x8 , L x9 and W x1 is 15 or less.

[0170] 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 x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, 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.

[0171] Examples of the group represented by the formula (L1-1) include the following divalent groups. TIFF2025105523000138.tif36147 Examples of the group represented by the formula (L1-2) include the following divalent groups. TIFF2025105523000139.tif23130 Examples of the group represented by the formula (L1-3) include the following divalent groups. TIFF2025105523000140.tif16147 Examples of the group represented by the formula (L1-4) include the following divalent groups. TIFF2025105523000141.tif13168L 55 is preferably a single bond or a group represented by the formula (L1-1).

[0172] Examples of the structural unit (a5-1) include the following structural units and the structural units in the following structural units where the methyl group corresponding to R in the structural unit (a5-1) is replaced by a hydrogen atom. 51 are mentioned. TIFF2025105523000142.tif104151 When the resin contains the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and still more preferably 3 to 15 mol% based on all the structural units of the resin.

[0173] 〈Structural unit (a6)〉 The structural unit (a6) is a structural unit having a -SO2- group, and preferably has a -SO2- group in the side chain. The structural unit having a -SO2- group may have a linear structure having a -SO2- group, a branched structure having a -SO2- group, or a cyclic structure (monocyclic and polycyclic structures) having a -SO2- group. Preferably, it is a structural unit having a cyclic structure having a -SO2- group, and more preferably, it is a structural unit having a cyclic structure (sultone ring) containing -SO2-O-.

[0174] Examples of the sultone ring include the following formula (T 1 -1), formula (T 1 -2), formula (T 1 -3) and formula (T 1 -4). The bonding site can be at any position. The sultone ring may be monocyclic, but is preferably polycyclic. The polycyclic sultone ring means a bridged ring containing -SO2-O- as an atomic group constituting the ring, and examples include the rings represented by formula (T 1 -1) and formula (T 1 -2). The sultone ring may contain, in addition to -SO2-O-, a heteroatom as an atomic group constituting the ring, like the ring represented by formula (T 1 -2). Examples of the heteroatom include an oxygen atom, a sulfur atom or a nitrogen atom, and preferably an oxygen atom. TIFF2025105523000143.tif2977

[0175] The sultone ring may have a substituent, and examples of the substituent include a halogen atom or an alkyl group having 1 to 12 carbon atoms which may have 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.

[0176] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, and a decyl group. Preferably, it is an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group. Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. Preferably, a trifluoromethyl group is included. Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a hydroxyalkyl group such as a 2-hydroxyethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkoxycarbonyl group include a group in which an alkoxy group such as a methoxycarbonyl group and an ethoxycarbonyl group is bonded to a carbonyl group. Preferably, an alkoxycarbonyl group having 6 or less carbon atoms is included, and more preferably a methoxycarbonyl group is included. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. From the viewpoint that the production of the monomer leading to the structural unit (a6) is easy, a sultone ring having no substituent is preferable.

[0177] As the sultone ring, a ring represented by the following formula (T1’) is preferable. TIFF2025105523000144.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 any integer from 0 to 9. When ma is 2 or more, a plurality of R 41 may be the same or different. The bonding site is at an arbitrary position.] X 11 is preferably an oxygen atom or a methylene group, more preferably a methylene group. R 41 Examples thereof are the same as those of the substituent of the sultone ring, and an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group is preferable. ma is preferably 0 or 1, more preferably 0.

[0178] Examples of the ring represented by formula (T1’) include the following rings. The bonding site is at an arbitrary position. Among them, those in which the bonding site is at the 1-position or the 3-position are preferable. TIFF2025105523000145.tif44147

[0179] The structural unit having a -SO2- group preferably further has a group derived from a polymerizable group. Examples of the polymerizable group include a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, a methacryloylthio group and the like. Among them, the monomer leading to the structural unit (a6) is preferably a monomer having an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer.

[0180] The structural unit (a6) is preferably a structural unit represented by the formula (a6-0). TIFF2025105523000146.tif4075[In the formula (a6-0), R x represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. A xx represents 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 may be replaced by -O-, -CO- or -N(R d )-. X 11 represents an oxygen atom, a sulfur atom or a methylene group. R 41 represents the same group as described above. ma represents any integer from 0 to 9. When ma is 2 or more, a plurality of R 41 may be the same or different. R c and R d each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.]

[0181] R x Examples of the halogen atom of R include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. R x 、R c and R d Examples of the alkyl group of include, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group and an n-hexyl group, etc., preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group. R xExamples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. R x is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group. A x Examples of the divalent saturated hydrocarbon group of A include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and those obtained by combining two or more of these groups may also be used. Specifically, linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, an undecane-1,11-diyl group, a dodecane-1,12-diyl group, a tridecane-1,13-diyl group, a tetradecane-1,14-diyl group, a pentadecane-1,15-diyl group, a hexadecane-1,16-diyl group, a heptadecane-1,17-diyl group, an ethane-1,1-diyl group, a propane-1,1-diyl group, and a propane-2,2-diyl group; branched alkanediyl groups such as 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; monocyclic divalent alicyclic saturated hydrocarbon groups which are cycloalkanediyl groups such as a cyclobutane-1,3-diyl group, a cyclopentane-1,3-diyl group, a cyclohexane-1,4-diyl group, and a cyclooctane-1,5-diyl group; Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, and the like. A x The bonding position to the sultone ring of x can be any position, but the position at the 1-position is preferred.

[0182] Examples of the structural unit (a6-0) include the following structural units. TIFF2025105523000147.tif93150

[0183] Among them, the 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 the structural units represented by formula (a6-1), formula (a6-2), formula (a6-7) and (a6-8) are more preferred. When the resin has the structural unit (a6), its content is preferably 1 to 50 mol%, more preferably 2 to 40 mol%, and still more preferably 3 to 30 mol% based on all the structural units of the resin.

[0184] <Structural unit (a7)> The resin may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)"). Specific examples of the structural unit (a7) include the structural units described in JP-A-2016-79235, and preferably a structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain or a structural unit having a sulfonio group and an organic anion in the side chain. The structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain is preferably a structural unit represented by formula (a7-A). TIFF2025105523000148.tif26117[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 a71represents a single bond, *-O-, *-CO-O-, *-O-CO-O-**, *-CO-NR a71 -**, *-NR a71 -CO-O-**, *-O-CO-NR a71 -** or *-Ax-Ph-Ay-**. R a71 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. * and ** represent bonding sites, and * represents the bonding site with the carbon atom to which R a7 is bonded. L a71 and L a72 each independently represent a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. X a72 represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, and *** represents the bonding site with L a71 na7 represents any integer from 0 to 2. When na7 is an integer of 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. RA - represents a sulfonate anion or a carboxylate anion. ZA + represents an organic cation.

[0185] R a7 and R a71 Examples of the alkyl group having 1 to 6 carbon atoms in include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. R a7 Examples of the halogen atom in include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.​ R a7 Examples of the alkyl group having 1 to 6 carbon atoms and a halogen atom in include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a dichloromethyl group, a triiodomethyl group, a diiodomethyl group, a tribromomethyl group, a dibromomethyl group, and the like. R a7 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0186] X a71 When is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025105523000149.tif3351[In the formula (X10), Ax represents a bonding species that binds to the carbon atom to which R a7 is bonded, and represents one or more bonding species selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond. Ay represents a bonding species that binds to L a71 and represents one or more bonding species selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond. Rx represents a halogen atom, a hydroxy group, a fluorinated alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. mx represents any integer from 0 to 4, and when mx is an integer of 2 or more, a plurality of Rx may be the same as or different from each other.] When either Ax or Ay is a single bond, the other is preferably at least one selected from the group consisting of an ether bond, a thioether bond, an ester bond, a carbonate ester bond, and an amide bond. When either of Ax and Ay is an amide bond, it is preferably a bond represented by -CO-NR a71 -. The bonding position of Ay in the phenylene group is preferably the m-position or the p-position relative to the bonding position of Ax, and more preferably the p-position. Rx is preferably, among others, 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 As, for example, a single bond, the following formula (X 10 -1) to formula (X 10 -10) groups represented. * is -R a7 represents the bonding site with the carbon atom to which it is bonded. ** represents the bonding site with L a71 . X 20 represents -O- or -NR a71 -. TIFF2025105523000150.tif43162 Formula (X 10 -1) to formula (X 10 -10) specific examples of the groups represented include the following groups. TIFF2025105523000151.tif87163 Among them, X 10 is preferably a single bond or a group represented by formula (X 10 -1') and formula (X 10 -3') to formula (X 10 -10'), more preferably a single bond or a group represented by formula (X 10 -1'), formula (X 10 -4'), formula (X 10 -5'), formula (X 10 -6') and formula (X 10 -10'), still more preferably a single bond, a group represented by formula (X 10 -1'), a group represented by formula (X 10 -5') or formula (X10 It is more preferably a group represented by -6’).

[0187] L a71 As the hydrocarbon group of L, one hydrogen atom is removed from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group formed by combining two or more of these groups, and X a71 and X a72 and the group that binds to a72 As the hydrocarbon group of L, one hydrogen atom is removed from a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group formed by combining two or more of these groups, and X a72 and RA - and the group that binds to L a71 and L a72 Examples of the chain hydrocarbon group of L and L include a group obtained by removing one hydrogen atom from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specifically includes a methyl group, an ethyl group, a propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, an iso-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decanyl group, an undecanyl group, a dodecanyl group, a tridecanyl group, a tetradecanyl group, a pentadecanyl group, a heptadecanyl group, etc. Examples of the alkenyl group include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, a nonenyl group. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 20, and even more preferably 1 to 10. L a71 and L a72 Examples of the alicyclic hydrocarbon group of L and L include a group obtained by removing one hydrogen atom from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cyclopentane group, a cyclohexane group, a cyclopentyl group, a cyclooctyl group, etc. L a71 and La72 Examples of the polycyclic cycloalkyl group of L and L include a cycloalkyl group having a cross-linked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a cross-linked structure include a norbornyl group and an adamantanyl group. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4.4.0]decanyl group and a steroid group (steroid skeleton). Examples of the ring in which two rings are spiro-bonded include a spirocycloalkyl 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 and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. Further, a double bond may be formed between two carbon atoms included in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group represented by the following formula can be given. TIFF2025105523000152.tif28158 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 12, more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms of the alicyclic hydrocarbon group is preferably 7 to 12. L a71 and L a72 Examples of the aromatic hydrocarbon group of L and L include an aryl group from which one hydrogen atom has been removed. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, and a fluorene group. The number of carbon atoms of the aromatic hydrocarbon group is preferably 5 to 14, more preferably 5 to 10. L a71 and L a72 When -CH2- included in the hydrocarbon group of L and L is replaced by -O-, -CO-, -S-, or -SO2-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the hydrocarbon group. L a71 and L a72Among the hydrocarbon groups, examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- 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 alkanedioxy group, an alkanedioxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, and the like. These replaced groups include the same ones as those described above within the range allowed by the upper limit of the number of carbon atoms. L a71 and L a72 Among the hydrocarbon groups, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a cyclic ether, a cyclic ketone, a cyclic ester (lactone), a cyclic thioether, a cyclic acetal, a cyclic sultone, and the like. Specifically, alicyclic hydrocarbon groups represented by the following formulas can be mentioned. The bonding positions of the alicyclic hydrocarbon groups mentioned in the following formulas can be at arbitrary positions. TIFF2025105523000153.tif46146L a71 and L a72 Among the hydrocarbon groups, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-. Examples of the group in which -CH2- is replaced by -O- or -S- include a furan ring and a thiophene ring, respectively. L a71 and L a72 Examples of the group formed by combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group include the group formed by combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, the group formed by combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, the group formed by combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and the group formed by combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group, and the above aromatic hydrocarbon group. The above combined groups are included. The group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group may be a condensed ring. Examples of the group in which -CH2- contained in the group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include the same groups as those exemplified in the present specification as long as the upper limit of the number of carbon atoms permits. L a71 and L a72 Examples of the substituent that the hydrocarbon group of a72 may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a71 and L a72 When a72 is a group combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group, substantially, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. Also, L a71 and L a72 By replacing -CH2- of the chain hydrocarbon group contained in the hydrocarbon group of a72 with -O-, -CO-, -S- or -SO2-, the hydrocarbon group of L a71 and L a72 can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, a thiol group, and a sulfonyl group. ZA in formula (a7-A) + is the same as the cation Z1 in the salt represented by the above-described formula (B1). + Examples thereof include the same ones.

[0188] Examples of the structural unit represented by formula (a7-A) include, for example, the following structural units, R a7 structural units in which the group corresponding to the methyl group of a7 is replaced by 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, etc.) and the structural units described in International Publication No. 2012 / 050015. ZA + represents an organic cation. TIFF2025105523000154.tif244163

[0189] TIFF2025105523000155.tif131157

[0190] The structural unit having a sulfonio group and an organic anion in the side chain is preferably a structural unit represented by the formula (a7-B). TIFF2025105523000156.tif27104[In the 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 represent a hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, and R b72 and R b73 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. A - represents an organic anion.] R a7 Examples of the halogen atom and the alkyl group which may have a halogen atom of R include the same halogen atoms and alkyl groups which may have a halogen atom as those in the formula (a7-A). R b71 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by include a phenylene group and a naphthylene group. R b72 and R b73 Examples of the hydrocarbon group represented by include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and group formed by combining these are the same as those described above. A b7Examples of the divalent linking group represented by 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 linear or branched alkanediyl groups, monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, or combinations thereof. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group; branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; and divalent polycyclic alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group. Examples of those in which -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- include the following divalent groups. However, the number of carbon atoms before -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- is 17 or less, respectively. In the following formula, * and ** represent bonding sites, and * represents the bonding site with R b71 and represents the bonding site with R. TIFF2025105523000157.tif123161[wherein 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 5represents 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 8 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0191] Examples of the structural unit containing the cation in formula (a7-B) include the structural units represented below and groups corresponding to the methyl group of R a7 in which the hydrogen atom, halogen atom (e.g., fluorine atom) or alkyl group having 1 to 6 carbon atoms which may have a halogen atom (e.g., trifluoromethyl group, etc.) is replaced with a group such as those. TIFF2025105523000158.tif75163

[0192] A - Examples of the organic anion represented by include sulfonate anions, sulfonylimide anions, sulfonylmethide anions, etc. A - The organic anion represented by is preferably a sulfonate anion, and more preferably an anion contained in the salt represented by the above-described formula (B1). Examples of the sulfonylimide anion, sulfonylmethide anion and carboxylate anion are the same as those exemplified as the anions of the acid generator (B) and the salt represented by formula (B3).

[0193] Examples of the structural unit represented by formula (a7-B) include the structural units represented below. TIFF2025105523000159.tif95157

[0194] When the resin contains the structural unit (a7), the structural unit (a7) may be contained alone or in combination of two or more. The total content of the structural unit (a7) is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, still more preferably 3 to 20 mol%, and even more preferably 3 to 15 mol% based on all the structural units of the resin.

[0195] The resin contained in the resist composition of the present invention is preferably a resin containing the structural unit (a2-A) and / or the structural unit (a1-4).

[0196] Each structural unit constituting the resin may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using a monomer that leads to these structural units. The content of each structural unit of the resin can be adjusted by the amount of the monomer used in the polymerization. The weight average molecular weight of the resin is preferably 2,000 or more (more preferably 2,500 or more, still more preferably 3,000 or more) and 50,000 or less (more preferably 30,000 or less, still more preferably 15,000 or less). In this specification, the weight average molecular weight is a value determined by gel permeation chromatography under the conditions described in the examples. In the resist composition of the present invention, when the resin is contained, the total content of the resin is preferably 1 mass% or more and 80 mass% or less, more preferably 3 mass% or more and 60 mass% or less, still more preferably 5 mass% or more and 50 mass% or less based on the solid content of the resist composition. The solid content of the resist composition and the content of the resin relative thereto can be measured by known analytical means such as liquid chromatography or gas chromatography.

[0197] <Other resins> The resist composition of the present invention may further contain a resin regardless of the presence or absence of a resin such as a phenolic hydroxyl group-containing compound (L). Examples of such resins include resins that do not contain the structural unit represented by formula (a2-A) and the structural unit represented by formula (a1-4), for example, a resin that contains the structural unit (a1) and does not contain the structural unit (a2) (hereinafter sometimes referred to as resin (AA)), a resin that contains the structural unit (a4) and / or the structural unit (a5) (hereinafter sometimes referred to as resin (X)), and the like. In addition to the structural unit (a1), resin (AA) may contain the structural unit (a3), the structural unit (a4), the structural unit (a5), the structural unit (a6), the structural unit (a7), and the like. Also, in resin (AA), the content ratio of each of the structural unit (a1), the structural unit (a3), the structural unit (a4), the structural unit (a5), the structural unit (a6), and / or the structural unit (a7) may be the same as the content ratio with respect to all the structural units of the resin described above.

[0198] Among the resins (X), a resin containing the structural unit (a4) is preferable. That is, it is preferably a resin containing a structural unit having a fluorine atom. Examples of the structural units that the resin (X) may further have include the structural unit (a3), the structural unit (a6), the structural unit (a7), and structural units derived from other known monomers. Among them, the resin (X) is preferably a resin composed only of the structural unit (a4) and / or the structural unit (a5), and more preferably a resin composed only of the structural unit (a4). When the resin (X) contains the structural unit (a4), in the resin (X), the content of the structural unit (a4) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, still more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. When the resin (X) contains the structural unit (a5), the content of the structural unit (a5) is 20 mol% or more, preferably 30 mol% or more, more preferably 40 mol% or more, and still more preferably 45 mol% or more, based on the total of all the structural units of the resin (X). Also, it is 100 mol% or less, preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less, and even more preferably 55 mol% or less. Specifically, it is 20 to 100 mol%, preferably 20 to 80 mol%, more preferably 30 to 70 mol%, still more preferably 40 to 60 mol%, and even more preferably 45 to 55 mol%. Further, 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) is 40 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more, and still more preferably 80 mol% or more, based on the total of all the structural units of the resin (X). Further, it is 100 mol% or less. Specifically, it is 40 to 100 mol%, preferably 60 to 100 mol%, more preferably 70 to 100 mol%, and still more preferably 80 to 100 mol%.The content rate of the structural unit (a2) that may further be contained is 1 to 45 mol%, preferably 2 to 30 mol%, more preferably 2 to 20 mol%, based on the total of all the structural units of the resin (X).

[0199] Each of the structural units constituting the resin (AA) and the resin (X) may be used alone or in combination of two or more, and can be produced by a known polymerization method (for example, radical polymerization method) using monomers that induce these structural units. The content rate of each structural unit of the resin (AA) and the resin (X) can be adjusted by the amount of monomers used for polymerization. The weight average molecular weight of the resin (AA) is preferably 2,000 or more (more preferably 2,500 or more, still more preferably 3,000 or more), and 50,000 or less (more preferably 30,000 or less, still more preferably 15,000 or less). The weight average molecular weight of the 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). The means for measuring the weight average molecular weight of the resin (AA) and the resin (X) is the same as that for resins. When the resist composition contains the resin (AA) and / or the resin (X), the content thereof is preferably 1 to 60 parts by mass, more preferably 1 to 50 parts by mass, still more preferably 1 to 40 parts by mass, even more preferably 2 to 30 parts by mass, and still even more preferably 2 to 8 parts by mass, based on 100 parts by mass of the resin.

[0200] <Solvent (E)> The content rate of the solvent (E) in the resist composition is usually 90% by mass or more and 99.9% by mass or less, preferably 92% by mass or more and 99% by mass or less, more preferably 94% by mass or more and 99% by mass or less. The content rate of the solvent (E) can be measured by known analysis means such as liquid chromatography or gas chromatography. 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; and the like. One kind of the solvent (E) may be used alone, or two or more kinds may be used.

[0201] <Quencher (C)> The quencher (C) includes a basic nitrogen-containing organic compound or a salt that generates an acid having a lower acidity than the acid generated from the acid generator (acid generator (B)) (however, excluding the salt represented by the formula (I)). When the resist composition contains the quencher (C), the content of the quencher (C) is preferably about 0.01 to 15% by mass, more preferably about 0.01 to 10% by mass, further preferably about 0.1 to 8% by mass, and even more preferably about 0.1 to 7% by mass based on the solid content of the resist composition. Examples of the basic nitrogen-containing organic compound include amines and ammonium salts. Examples of the amines include aliphatic amines and aromatic amines. Examples of the aliphatic amines include primary amines, secondary amines, and tertiary amines. Examples of the amine include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyldihexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonylamine, ethyldidecylamine, dicyclohexylmethylamine, tris[2-(2-methoxyethoxy)ethyl]amine, triisopropanolamine, ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'-diethyldiphenylmethane, 2,2'-methylenebisaniline, imidazole, 4-methylimidazole, pyridine, 4-methylpyridine, 1,2-di(2-pyridyl)ethane, 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'-dipyridylsulfide, 4,4'-dipyridyldisulfide, 2,2'-dipyridylamine, 2,2'-dipicolylamine, bipyridine, etc. Aromatic amines such as diisopropylaniline are preferable, and 2,6-diisopropylaniline is more preferable. 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.

[0202] The acidity of a salt that generates an acid with a lower acidity than the acid generated from the acid generator is indicated by the acid dissociation constant (pKa). A salt that generates an acid with a lower acidity than the acid generated from the acid generator is a salt having an acid dissociation constant of the acid generated from the salt usually of -3 < pKa, preferably -1 < pKa < 7, and more preferably 0 < pKa < 5. 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. Preferably, it is 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 containi...

Claims

1. An acid generator containing a salt represented by formula (I). [In formula (I), m3 represents 0 or 1. R ４ represents a halogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and the hydrocarbon group may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -CO-, -S-, -SO ２ -. R ５ is -X １ -R １０ or -X １ -L １０ -X ２ -R １０ represents. X １ and X ２ each independently represents *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * represents the binding site to the benzene ring or L １０ ).) L １０ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and the -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -SO ２ - or -CO-. R １０ represents a group represented by the formula (IC). m4 represents any integer from 0 to 4, and when m4 is 2 or more, the plurality of Rs ４ may be the same as or different from each other. m5 represents any integer from 1 to 4, and when m5 is 2 or more, the plurality of Rs ５ may be the same as or different from each other. However, 1 ≤ m4 + m5 ≤ 5. Z ＋ represents an organic cation. [In formula (IC), R Ａ represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents any integer from 0 to 2. When u1 is 2, the plurality of Rs Ａ are either the same or different. s1 represents 1 or 2. t1 represents 0 or 1. However, the sum of s1 and t1 is 1 or 2. L １２ represents a hydrocarbon group having 1 to 36 carbon atoms which may have a single bond or a substituent, and the -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO ２ -. * represents a bonding site. ]

2. X １ The acid generator according to claim 1, wherein X is *-CO-O- or *-O-CO-.

3. The acid generator according to claim 1, wherein m5 is 2 or 3.

4. A resist composition containing the acid generator according to any one of claims 1 to 3 and an acid generator other than the acid generator.

5. The resist composition according to claim 4, wherein the acid generator other than the acid generator according to any one of claims 1 to 3 contains a salt represented by formula (B1) or a salt represented by formula (B3). [In formula (B1), L b1 represents a (nb1 + 1)-valent hydrocarbon group which may have a single bond or substituents, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -. L b2 represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO 2 -. Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH 2 - in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO 2 - or -CO-. nb1 represents any integer from 1 to 6. When nb1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. Z1 ＋ represents an organic cation. [In formula (B3), A １ represents a nitrogen atom or a carbon atom. L ｂ２ ' represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH 2 - may be replaced by -O-, -S-, -CO- or -SO 2 -. Y ｂ１ ' represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH contained in the cyclic hydrocarbon group 2 - may be replaced by -O-, -S-, -SO 2 - or -CO-, and two -SO 2 -L ｂ２’ -Y ｂ１’ may combine together to form a ring containing A １ may be formed. nb5 represents 2 or 3. When nb5 is 2, A １ represents a nitrogen atom, and when nb5 is 3, A １ represents a carbon atom. The groups within the plurality of parentheses may be the same as or different from each other. Z2 ＋ represents an organic cation.

6. Furthermore, the resist composition according to claim 4, further containing a compound having a phenolic hydroxyl group or a benzoic acid carboxy group and / or a compound in which the hydroxyl group of the phenolic hydroxyl group or the carboxy group of the benzoic acid carboxy group is protected by an acid-labile group.

7. The resist composition according to claim 6, wherein the compound is a resin, and the resin contains a resin containing a structural unit represented by formula (a2 - A) or a structural unit represented by formula (a1 - 4). [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, an optionally halogenated 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. A ａ２１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ２８ -. 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 any integer from 1 to 5. When nA2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na21 represents any integer from 0 to 4, and when na21 is 2 or more, a plurality of Rs ａ２７ may be the same as or different from each other. mc represents any integer from 0 to 2. ] [In formula (a1 - 4), R ａ１ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ１７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group. A ａ１１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the -CH ２ - in the alkanediyl group may be replaced by -O-, -CO- or -NR ａ１８ -. 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, and R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the -CH 2 - contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na11 represents any integer from 0 to 4, and when na11 is 2 or more, a plurality of Rs ａ１７ may be the same as or different from each other. mc represents any integer from 0 to 2. ]

8. The resin further contains a structural unit having an acid-labile group other than the structural unit represented by formula (a1 - 4), and the structural unit having an acid-labile group other than the structural unit represented by formula (a1 - 4) is 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 - 5), and a structural unit represented by formula (a1 - 6). The resist composition according to claim 7, comprising at least one selected from the group consisting of: [In formula (a1 - 0), formula (a1 - 1), and formula (a1 - 2), L a01 , L ａ１ and L ａ２ each independently represents -O- or *-O-(CH ２ ), ｋ１ -CO-O-, k1 represents any integer from 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 combining these, and the alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. R ａ６ and R ａ７ each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. m1' represents any integer from 0 to 14. n1 represents any integer from 0 to 10. n1' represents any integer from 0 to 3. ] [In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Z a1 represents a single bond or *-(CH 2 ) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, and * represents the bonding site with L 51 . L 51 、 L 52 、 L 53 and L 54 each independently represents -O- or -S-. s1 represents any integer from 1 to 3. s1' represents any integer from 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. X a61 represents a single bond, -CO-O-*, or -CO-NR a65 -*, where * represents a bond to Ar, and R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 represents a single bond, *-O-L a61 - or *-CO-O-L a62 -, where * represents a bond to Ar, and L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an optionally substituted aromatic hydrocarbon group having 6 to 20 carbon atoms. ]

9. (1) A step of applying the resist composition according to claim 4 onto a substrate, (2) A step of drying the applied composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, A method for manufacturing a resist pattern including these steps.

10. A salt represented by formula (I). [In formula (I), m3 represents 0 or 1. R ４ represents a halogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and the hydrocarbon group may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -CO-, -S-, -SO ２ -. R ５ is -X １ -R １０ or -X １ -L １０ -X ２ -R １０ represents. X １ and X ２ each independently represents *-CO-O-, *-O-CO-, *-O-CO-O- or *-O- (where * represents the bonding site to the benzene ring or L １０ .). L １０ represents a hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -SO ２ - or -CO-. R １０ represents a group represented by the formula (IC). m4 represents any integer from 0 to 4, and when m4 is 2 or more, the plurality of Rs ４ may be the same as or different from each other. m5 represents any integer from 1 to 4, and when m5 is 2 or more, the plurality of Rs ５ may be the same as or different from each other. Provided that 1 ≤ m4 + m5 ≤ 5. Z ＋ represents an organic cation. [In formula (IC), R Ａ represents a saturated hydrocarbon group having 1 to 12 carbon atoms. u1 represents any integer from 0 to 2. When u1 is 2, the plurality of Rs Ａ are 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 １２ represents a hydrocarbon group having 1 to 36 carbon atoms which may have a single bond or a substituent, and -CH 2 - in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO ２ -. * represents a bonding site. ]

11. X １ The salt according to claim 10, wherein X is *-CO-O- or *-O-CO-

12. The salt according to claim 10, wherein m5 is 2 or 3.

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