JPH10330725A - Acid generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an acid generator which can generate a sulfonic acid at a temperature as low as room temperature or below when stimulated by moisture by selecting a compound having a specified chemical structure. SOLUTION: This generator has a chemical structure represented by formula I (wherein X is an element selected among O, S, Se and Te) or formula II. It is desirable that the chemical structure represented by formula I or II is the one represented by formula III [wherein X is as defined in formula I; R<1> is a chemical species selected among halogens, alkyls, aralkyls and aryls, and R<2> is hydrogen or a chemical species having a chemical structure represented by formula V (wherein Z<1> , Z<2> and Z<3> are chemical species selected among alkyls, aralkyls and aryls) or formula IV (wherein R<1> and R<2> are as defined in formula III]. This generator can be used in combination with a composition capable of reacting in the presence of an acid as a catalyst or an initiator. Such a composition is exemplified by a cationically polymerizable composition or a composition comprising a hydrolyzable silicon compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an acid generator, and more particularly to an acid generator capable of generating an acid at a low temperature.

[0002]

2. Description of the Related Art Conventionally, an acid generator, that is, a compound which generates an acid by a certain stimulus, has been used for curing an epoxy resin. Typical examples of the acid generator include benzylsulfonium salts, benzylammonium salts, and benzylphosphonium salts as described in “New Development of Epoxy Resin Curing Agent” (published by CMC Inc. in 1994). Most of these acid generators generate an acid by light or heat. For example, photostimulable acid generators have been used in the electronics field as curing catalysts for photoresist materials.

[0003]

However, in the case of the photostimulable acid generator, the irradiation range of the light is greatly affected by the shape of the light source and the reaction vessel due to the nature of the light, so that uniform irradiation of the reaction system is difficult. However, there is a problem that the generation of acid is insufficient in the reaction system. In addition, most of heat-stimulable acid generators require 10 to generate an acid.
Since it is necessary to raise the temperature to 0 to 150 ° C., there is a problem that the reaction system that can be used is limited.

[0004] It is an object of the present invention to provide a new type of acid generator capable of generating sulfonic acid even at a low temperature of room temperature or lower by stimulation of moisture.

Another object of the present invention is to provide an acid generator which does not have the above-mentioned disadvantages of photostimulation and heat irritation. .

[0006]

In order to achieve the above object, an acid generator of the present invention has a chemical structure represented by the following chemical formula (I) or (II). is there.

[0007]

Embedded image (X represents an element selected from O, S, Se, and Te.)

Embedded image

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION That is, the present inventors have found that a compound having the chemical structure represented by the above chemical formula (I) or (II) generates an acid even at a low temperature of room temperature or lower by hydrolysis. And arrived at the present invention.

In the above chemical formula (I), X is O, S, S
e is an element selected from e and Te, and among them, S is preferable from the viewpoint of easy acid generation.

In the present invention, the chemical structure represented by the chemical formula (I) or (II) is represented by the following chemical formula (II)
It is preferable that the compound has the chemical structure represented by I) or (IV).

[0011]

Embedded image (X represents an element selected from O, S, Se, and Te. R ¹
Represents a chemical species selected from a halogen group, an alkyl group, an aralkyl group, and an aryl group. R ² is hydrogen or the following chemical formula (V)

Embedded image Represents a chemical species having the chemical structure represented by Z ¹ , Z ² ,
Z ³ represents a chemical species selected from hydrogen, an alkyl group, an aralkyl group, and an aryl group. )

Embedded image (R ¹ represents a chemical species selected from a halogen group, an alkyl group, an aralkyl group, and an aryl group. R ² represents hydrogen or the following chemical formula (V)

Embedded image Represents a chemical species having the chemical structure represented by Z ¹ , Z ² ,
Z ³ represents a chemical species selected from hydrogen, an alkyl group, an aralkyl group, and an aryl group. In the chemical structure represented by formula (III) or (IV) of the present invention, examples of the halogen group for R ¹ include fluorine, chlorine, bromine, and iodine.

Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group and an n-pentyl group.
-Linear alkyl groups such as hexyl, n-octyl, n-decyl, n-dodecyl, n-octadecyl, isopropyl, isobutyl, sec-butyl, tert-
Examples thereof include branched alkyl groups such as butyl group, isopentyl group, neopentyl group, tert-pentyl group, and 2-ethylhexyl group, and cycloalkyl groups such as cyclopropyl group, cyclopentyl group, cyclohexyl group, norbornyl group, and adamantyl group. .

Examples of the aralkyl group include a benzyl group,
Examples include a phenethyl group, styryl group, cinnamyl group, benzhydryl group, and trityl group.

Examples of the aryl group include a phenyl group, a naphthyl group, a tolyl group, a xylyl group, a cumenyl group and a mesityl group.

The above alkyl, aralkyl and aryl groups are further substituted with various substituents such as halogen, cyano, carboxyl, sulfonic, nitro, hydroxy, and alkoxy groups. It may be something.

In the acid generator of the present invention, R ² is hydrogen or a chemical species having a chemical structure represented by the above chemical formula (V).

In R ² , Z ¹ , Z ² and Z ³ each represent a chemical species selected from hydrogen, an alkyl group, an aralkyl group and an aryl group. Specific examples of the alkyl group, aralkyl group, and aryl group include the same groups as those described for R ¹ .

R ¹ is a chemical species selected from a halogen group, a fluoroalkyl group and an aryl group in terms of the strength of the acid generated by the acid generator as a catalyst or an initiator and the ease of acid generation. Preferably, a chemical species selected from a tolyl group, a xylyl group, a chlorophenyl group, a trifluoromethyl group, and a chloro group is most preferable.

R ² represents hydrogen and trimethylsilyl, triethylsilyl, isopropyldimethylsilyl, methyldiisopropylsilyl, triisopropylsilyl, and trimethylsilyl, in terms of availability of industrial raw materials and economy. (Triphenylmethyl) dimethylsilyl group,
Triphenylsilyl group, t-butyldimethylsilyl group,
Methyl di-t-butylsilyl group, t-butyldiphenylsilyl group, tribenzylsilyl group, tri-p-xylylsilyl group, o-hydroxystyryldimethylsilyl group,
Dimethylphenylsilyl groups are preferred, hydrogen and trimethylsilyl groups are most preferred.

The above R ¹ and R ² are represented by the following formulas (1) to
Combinations as in (8) are preferred in terms of the strength of the acid generated by the acid generator as a catalyst or initiator, ease of acid generation, and economy, and are represented by formulas (1) to (5).
(4) is particularly preferred.

[0021]

Embedded image Next, a method for producing the acid generator of the present invention will be described with reference to an example.

A sulfonyl isocyanate compound represented by the following general formula (VI) is reacted with a compound having a group represented by the following general formula (VII) at a temperature in the range of -10 to 80 ° C.

[0023]

Embedded image

Embedded image In the formula, X, R ¹ and R ² represent the same substituents as those described in formulas (III) and (IV).

In the present invention, a catalyst can be used during the reaction, if necessary. Examples of the catalyst include tertiary amines such as triethylamine and 1,8-diazabicyclo [5.4.0] -7-undecene (DBU). Examples thereof include organic compounds such as amine compounds, dibutyltin dilaurate, and tin octylate. The amount of the catalyst used is 0.001 to 1 with respect to the sulfonyl isocyanate compound.
% By weight.

If necessary, a solvent may be used during the reaction.

The acid generator of the present invention can be used in combination with a composition capable of reacting with an acid as a catalyst or an initiator.

Examples of the composition capable of reacting with an acid as a catalyst or an initiator include a cationically polymerizable composition and a composition comprising a hydrolyzable silicon compound.
The present invention is not particularly limited to these.

Examples of the cationic polymerizable composition include a composition composed of a vinyl monomer and a composition composed of a ring-opening polymerizable monomer. A very large number of monomers are industrially used. Is illustrated.

As the vinyl monomer, styrene, α
Monovinyl aromatic compounds such as -methylstyrene and p-methoxystyrene, vinyl halides such as vinyl chloride, acrylic monomers such as methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate, isobutyl vinyl ether, etc. Vinyl ethers.

When water is added to a composition comprising a vinyl monomer and the acid generator of the present invention is added, an acid (proton) is generated by hydrolysis, and the proton is added to the olefin as an initiator. Generates a carbon cation and initiates polymerization.

Examples of ring-opening polymerizable monomers include cyclic ethers such as ethylene oxide, propylene oxide, epichlorohydrin, cyclohexene oxide, tetrahydrofuran and epoxy resins, and cyclic esters such as ε-caprolactone and β-propiolactone. .

When water is added to a system comprising the ring-opening polymerizable monomer and the acid generator of the present invention, the generated protons are added to ether oxygen as an initiator, and the oxygen and the adjacent carbon are added. Is cleaved to open the ring, producing a carbocation. The monomers react sequentially with this to form a polymer.

The amount of the acid generator used in the present invention is preferably 0.001 to 10 parts by weight, more preferably 0.01 to 1 part by weight, based on 100 parts by weight of the cationically polymerizable composition.

Examples of the composition comprising a hydrolyzable silicon compound include a composition comprising a hydrolyzable silane compound and a composition comprising a monomer or polymer having a hydrolyzable silyl group at a terminal or a side chain.

Examples of the hydrolyzable silane compound include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane and tetrabutoxysilane, or tetraacetoxysilane or tetrachlorosilane.
Methyltrimethoxysilane, methyltriethoxysilane, methyltris (methoxyethoxy) silane, methyltriacetoxysilane, methyltripropoxysilane,
Methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltris (methoxyethoxy) silane,
Phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, γ-chloropropyltriacetoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltri Methoxysilane, γ-aminopropyltriethoxysilane, γ
-Mercaptopropyltrimethoxysilane, γ-mercaptopropyltris (methoxyethoxy) silane, N-
β- (aminoethyl) -γ-aminopropyltrimethoxysilane, β-cyanoethyltriethoxysilane, methyltriphenoxysilane, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxy Methyltriethoxysilane, α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, β
-Glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane, α-glycidoxypropyltrimethoxysilane, α-glycidoxypropyltriethoxysilane, β-glycidoxypropyltrimethoxysilane, β -Glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ
-Glycidoxypropyltripropoxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltris (methoxyethoxy) silane, γ-
Glycidoxypropyl triphenoxy silane, α-glycidoxybutyl trimethoxy silane, α-glycidoxy butyl triethoxy silane, β-glycidoxy butyl trimethoxy silane, β-glycidoxy butyl triethoxy silane, γ -Glycidoxybutyltrimethoxysilane, γ-glycidoxybutyltriethoxysilane, δ-
Glycidoxybutyltrimethoxysilane, δ-glycidoxybutyltriethoxysilane, (3,4-epoxycyclohexyl) methyltrimethoxysilane, (3,4-
Epoxycyclohexyl) methyltriethoxysilane,
β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltripropoxysilane, β-
(3,4-epoxycyclohexyl) ethyl tributoxy silane, β- (3,4-epoxycyclohexyl)
Ethyltris (methoxyethoxy) silane, β- (3,
4-epoxycyclohexyl) ethyltriphenoxysilane, γ- (3,4-epoxycyclohexyl) propyltrimethoxysilane, γ- (3,4-epoxycyclohexyl) propyltriethoxysilane, δ- (3,4
-Epoxycyclohexyl) butyltrimethoxysilane, trialkoxysilanes such as δ- (3,4-epoxycyclohexyl) butyltriethoxysilane, triacyloxysilanes or triphenoxysilanes, and dimethyldimethoxysilane, phenylmethyldimethoxysilane, dimethyldimethoxysilane Ethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropylmethyldiethoxysilane, dimethyldiacetoxysilane, γ
-Methacryloxypropylmethyldimethoxysilane, γ
-Methacryloxypropylmethyldiethoxysilane, γ
-Mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, glycidoxymethylmethyldimethoxy Silane, glycidoxymethylmethyldiethoxysilane, α-glycidoxyethylmethyldimethoxysilane, α-glycidoxyethylmethyldiethoxysilane, β-glycidoxyethylmethyldimethoxysilane, β-glycidoxyethylmethyldi Ethoxysilane, α-glycidoxypropylmethyldimethoxysilane, α-glycidoxypropylmethyldiethoxysilane, β-glycidoxypropylmethyldimethoxysilane, β-glycidoxypropylmethyl Ludiethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldipropoxysilane, γ-glycidoxypropylmethyldibutoxysilane, γ-grid Sidoxypropylmethylbis (methoxyethoxy) silane, γ-glycidoxypropylmethyldiphenoxysilane, γ-glycidoxypropylmethyldiacetoxysilane, γ-glycidoxypropylethyldimethoxysilane, γ-glycidoxypropylethyl Diethoxysilane, γ-glycidoxypropylvinyldimethoxysilane, γ-glycidoxypropylvinyldiethoxysilane, γ-glycidoxypropylphenyldimethoxysilane, γ-glycidoxypropylphenyldiethoxysilane Alkoxysilane, and di phenoxy silane or diacyl oxy silanes.

Next, a monomer or polymer having a hydrolyzable silyl group at a terminal or a side chain will be described.

As the hydrolyzable silyl group, the following general formula (VIII)

Embedded image (N is an integer of 1 to 3).

Here, R ³ represents a chemical species selected from an alkyl group, an aralkyl group and an aryl group. Specific examples of the alkyl group, the aralkyl group and the aryl group include those represented by the formula (I)
II) include the same as described for R ¹ of (IV).

When n = 1, there are two R ^{3 in} the formula (VIII), in which case each may represent a different substituent.

X 'is not particularly limited as long as it is a functional group capable of being hydrolyzed, that is, a group which forms a silanol group by a hydrolysis reaction. Specific examples thereof include a halogen group, an alkoxy group, an acyloxy group and an oximo group. Groups.

Examples of the alkoxy group include a methoxy group,
An ethoxy group, a propoxy group, a butoxy group, a methoxyethoxy group, and an ethoxyethoxy group can be exemplified.

Examples of the acyloxy group include an acetoxy group, a propionyloxy group and a butanoyloxy group.

Examples of the oximo group include a methylethylketooximo group.

When n = 2 and 3, there are two or three X's in formula (VIII), in which case each may represent a different substituent.

Examples of the main chain portion of the monomer or polymer having a hydrolyzable silyl group at the terminal or side chain include polyether polymers, polyester polymers, acrylic polymers, and hydrocarbon polymers.

Examples of polyether polymers include polyoxyethylene, polyoxypropylene, and polyoxytetramethylene.

Examples of polyester-based polymers include polycondensation of dibasic acids such as adipic acid and azelaic acid with diols such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol, and ε-caprolactone such as ε-caprolactone. Examples include polyesters obtained by ring-opening polymerization of lactones.

Examples of the acrylic polymer include polymers obtained by radical copolymerization of acrylic monomers such as ethyl acrylate, butyl acrylate, and allyl acrylate, and polymers obtained by copolymerizing these acrylic monomers with methyl methacrylate, styrene, acrylonitrile, and the like. Can be used.

Examples of the hydrocarbon polymer include olefinic compounds having 1 to 6 carbon atoms, ie, ethylene, propylene, 1-butene, isobutene, 2-butene, 2-methyl-1-butene, 3-methyl-1-butene, Penten, 4-
Polymers obtained by homopolymerization or copolymerization of olefin compounds such as methyl 1-pentene, hexene, vinylcyclohexene, etc., for example, polyisobutylene, ethylene-propylene copolymers, or homopolymerization or copolymerization of diene compounds Examples of the polymer include polyisoprene or a hydrogenated product thereof, a copolymer of isobutylene and isoprene or a hydrogenated product thereof, and a copolymer of isoprene and butadiene or a hydrogenated product thereof.

When water is added to the composition comprising the hydrolyzable silicon compound to which the acid generator of the present invention has been added, the generated acid serves as a catalyst to cause hydrolysis of the silyl group, resulting in condensation between the monomers. Form a siloxane bond to form a polymer.

The amount of the acid generator of the present invention to be used is preferably 0.001 to 10 parts by weight, preferably 0.01 to 1 part by weight, per 100 parts by weight of the composition comprising the hydrolyzable silicon compound.
Parts by weight are more preferred.

When the acid generator of the present invention is used in combination with a composition capable of reacting with an acid as a catalyst or an initiator, an aliphatic hydrocarbon solvent or an aromatic hydrocarbon may be further used depending on the purpose of use. Solvents such as hydrogen solvent, ester solvent, ether solvent, ketone solvent, carbonate solvent, aprotic polar solvent, calcium carbonate, magnesium carbonate, talc, mica, graphite, kaolin, clay, silica, alumina, titania , Magnesia, zeolite, aluminum hydroxide, magnesium hydroxide, zinc oxide, diatomaceous earth, clay, wood flour, walnut husk flour, rice husk flour, pulp, cotton chips, resin particles, resin paste,
Filler such as glass beads, aluminum powder, zinc powder, glass balloon, resin balloon, asbestos, sepiolite, glass fiber, carbon fiber, resin fiber, gypsum fiber, benzoic acid, phthalic acid, trimellitic acid, pyromellitic acid, adipine Derivatives such as acid, sebacic acid, fumaric acid, maleic acid, itaconic acid and citric acid, plasticizers such as chlorinated hydrocarbons, polyesters, polyethers, and epoxy resins, coloring agents such as various pigments and dyes, and various silane cups Adhesion-imparting agents such as ring agents, various isocyanate compounds, various epoxy compounds, various UV absorbers, various UV reflectors, various antioxidants, various light stabilizers and other deterioration inhibitors, calcium chloride, lithium chloride, barium oxide , Calcium oxide, potassium fluoride, potassium thiocyanate, thiocyanic acid Thorium, ammonium thiocyanate, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, tetrahydrosulfolane, tetrahydrofuran, 1,4-dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene Glycol dimethyl ether, tetraethylene glycol dimethyl ether,
Polyethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol diethyl ether, triethylene glycol diethyl ether, tetraethylene glycol diethyl ether, polyethylene glycol diethyl ether, various cellosolves, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, etc. , But is not limited thereto.

A composition comprising the acid generator of the present invention and a composition capable of reacting with an acid as a catalyst or an initiator is used as a paint, coating material, adhesive,
It is suitable for applications such as inks, molded products, and sealants.

[0054]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but it should not be construed that the invention is limited thereto.

Each measurement in the examples is performed by the following method.

(A) 1H-NMR measurement: About 0.8 ml of the reaction solution was sampled and measured using a JNM-EX270 FT-NMR measurement device manufactured by JEOL Ltd.

(B) IR spectrum: DIGILAB F manufactured by Nippon Bio-Rad Laboratories, Inc.
It measured using the TS-40 FT-IR measuring device. A small amount of the reaction solution was sampled, diluted with chloroform, sandwiched between rock salt plates, and measured.

Example 1 Compound 65 of the following formula (IX)
To 3.4 mg (2 mmol) of chloroform-d (2 m
l) was added and mixed well. Here, 788.8 mg of p-toluenesulfonyl isocyanate represented by the formula (X)
(4 mmol) was slowly added dropwise.

When the reaction was traced by 1H-NMR measurement, it was found that the peak of hydrogen at the α-position of sulfur changed, and it was confirmed that the reaction proceeded almost quantitatively in 2 hours. The NMR spectrum of the product was 2.9 ppm.
It has a peak at an area ratio of 1: 2 at 4 ppm, and is considered to be hydrogen of methylene at the α-position of sulfur and hydrogen of methylene at the α-position of ether oxygen, respectively. Since the peak of hydrogen of the sulfonyl group was also confirmed, the compound was confirmed to be a compound of the following formula (XI).

After 0.04 g of water was added to the reaction system and mixed well, the aqueous layer was removed, and the 1H-NMR measurement of the organic layer was carried out. The peak of the sulfonic acid group of p-toluenesulfonic acid was found to be 5.1 ppm. , And a peak characteristic of hydrogen at the α-position of sulfur in thiourethane was confirmed. Also, I
In the R spectrum, characteristic absorption of the carbonyl group of thiourethane was confirmed at 1700 cm- ¹ , and 1620c
Characteristic absorption of amino group was observed at m- ¹ and 3270 cm- ¹ .

From these results, it was found that the hydrolysis of the compound of the following formula (XI) proceeds to generate an acid.

[0062]

Embedded image (Example 2) 142.3 mg of a compound of the following formula (XII)
Chloroform-d (2 ml) was added to (0.5 mmol) and mixed well. Here, 197.2 mg of p-toluenesulfonyl isocyanate represented by the above formula (X)
(1 mmol) was slowly added dropwise.

1H-NMR measurement showed that the peak of the hydrogen at the α-position of sulfur changed, confirming that the reaction had proceeded almost quantitatively. The NMR spectrum of the product has peaks at an area ratio of 1: 2 at 2.9 ppm and 3.4 ppm, respectively, hydrogen of methylene at α-position of sulfur,
It was considered to be hydrogen of methylene at the α-position of ether oxygen, and a hydrogen peak of a p-toluenesulfonyl group having an area ratio corresponding to these was also confirmed. In the IR spectrum, characteristic absorption of the amino group of thiourethane was observed at 1620 cm- ¹ . Thus, the compound was identified to be a compound represented by the following formula (XIII).

After 0.01 g of water was added to the reaction system and mixed well, the aqueous layer was removed, and the organic layer was subjected to 1 H-NMR measurement. As in Example 1, p-toluenesulfone was adjusted to 5.1 ppm. The peak of the sulfonic acid group of the acid was confirmed, and a peak characteristic of hydrogen at the α-position of sulfur of thiourethane was confirmed. In the IR spectrum, 1700 cm
- ¹ characteristic absorption of the carbonyl group of the thiourethane is confirmed, 1620cm- ^1, 3270cm- characteristic absorption of amino group was observed at ^1. From these results, the formula (XIII)
It has been found that the hydrolysis of the compound proceeds to generate an acid.

[0065]

Embedded image

[0066]

The acid generator of the present invention, unlike conventional acid generators, can generate an acid by stimulating moisture even at a low temperature of room temperature or lower, so that it can be widely used in reaction systems under various conditions. Can be used.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07F 7/10 C07F 7/10 P

Claims (2)

[Claims] 1. An acid generator having a chemical structure represented by the following chemical formula (I) or (II). Embedded image (In the formula, X represents an element selected from O, S, Se, and Te.) 2. The acid generator according to claim 1, wherein the acid generator has a chemical structure represented by the following chemical formula (III) or (IV). Embedded image (Wherein, X represents an element selected from O, S, Se, Te. R ¹ represents a halogen group, an alkyl group, an aralkyl group,
Represents a chemical species selected from an aryl group. R ² is hydrogen,
Or the following chemical formula (V): Represents a chemical species having the chemical structure represented by Z ¹ , Z ² ,
Z ³ represents a chemical species selected from hydrogen, an alkyl group, an aralkyl group, and an aryl group. ) (R ¹ represents a chemical species selected from a halogen group, an alkyl group, an aralkyl group, and an aryl group. R ² represents hydrogen or the following chemical formula (V): Represents a chemical species having the chemical structure represented by Z ¹ , Z ² ,
Z ³ represents a chemical species selected from hydrogen, an alkyl group, an aralkyl group, and an aryl group. )