TWI607989B - Compounds containing thiol groups and single-liquid epoxy resin compositions - Google Patents

Description

Thiol group-containing compound and single-liquid epoxy resin composition

The present invention relates to a specific thiol group-containing compound, and further relates to a curing agent for an epoxy resin containing the thiol compound, and a one-component epoxy resin composition containing the same.

As a curing agent for an epoxy resin, a composition containing a thiol group-containing compound is excellent in low-temperature curability, and various studies have been conducted. For example, Japanese Laid-Open Patent Publication No. Hei 8-269203 (Patent Document 1) discloses a resin composition obtained by reacting a halogen-terminated polyether polymer with a hydrosulfide base and/or a polysulfide base in an amide. A thiol group-containing polyether polymer as a resin hardener, wherein the halogen terminal polyether polymer is added to an epihalohydrin having a polyether moiety in the main chain and having three or more hydroxyl groups at the terminal. Obtained from a polyol. Depending on the hardened material, the hardening properties such as hardening time and hardening temperature are different. Therefore, the hardener is required to prepare a plurality of specific hardeners suitable for a specific use in a manner compatible with various uses of the hardened materials. .

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 8-269203

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel thiol group-containing compound, and to provide a novel single-liquid epoxy resin hardener comprising the thiol group-containing compound.

Another object of the present invention is to provide an epoxy resin cured product obtained by hardening the one-liquid epoxy resin composition.

In order to solve the above problems, the inventors of the present invention have solved the above problems by a specific novel thiol group-containing compound.

That is, the present invention is as follows.

[1] A compound containing a thiol group, which is represented by the formula (1),

(In the formula (1), R represents a hydrogen atom, a hydrocarbon group which may have a substituent, or -CH ₂ -OC(O)-[CH ₂ ] _l -SH (1 is an integer of 1 to 8); X and The Z series independently represents a divalent aliphatic hydrocarbon group which may have a substituent; the Y system represents a selected from -OC(O)-, -C(O)O-, -NHC(O)-, -C(O)NH- , -C(O)- and -C(O)S-, a divalent group; m is an integer from 1 to 8; n is an integer from 1 to 8).

[2] The thiol group-containing compound according to [1], wherein R is a hydrogen atom or a saturated or unsaturated linear or branched hydrocarbon group having 1 to 15 carbon atoms, and the X and Z systems are independently A divalent alkylene group having 1 to 20 carbon atoms which may have a substituent.

[3]. The thiol group-containing compound of [1] or [2], which is 2-ethyl-2-{{{3-[(3-mercaptopropyl)thio]propanyl}oxy Methyl}propane-1,3-diylbis(3-mercaptopropionate).

[4] A curing agent for an epoxy resin, which comprises the thiol group-containing compound according to any one of [1] to [3].

[5] A one-component epoxy resin composition containing the thiol group-containing compound (component (1)) according to any one of [1] to [3], and having two or more molecules in the molecule. Epoxy based epoxy resin (ingredient (2)).

[6] The one-component epoxy resin composition according to [5], which further contains a solid dispersion type latent curing accelerator (ingredient (3)).

[7] The one-component epoxy resin composition according to [6], wherein the content of the component (3) is 0.1 to 100 parts by mass, when the content of the component (2) is 100 parts by mass.

[8] The one-component epoxy resin composition according to any one of [5] to [7] wherein further comprising a boronic acid ester compound, a titanate compound, an aluminate compound, and a zirconate One or more compounds (component (4)) of a compound, an isocyanate compound, a carboxylic acid, an acid anhydride, and a mercapto organic acid.

[9] The one-component epoxy resin composition according to [8], wherein the content of the component (4) is 0.001 to 50 parts by mass, when the content of the component (2) is 100 parts by mass.

[10] The one-component epoxy resin composition according to any one of [5] to [9], further comprising a compound having two or more thiol groups in the molecule different from the component (1) ( Ingredients (5)).

[11] The one-component epoxy resin composition according to [10], wherein the component (5) is trimethylolpropane ginseng (3-mercaptopropionate).

[12]. The liquid-liquid epoxy resin composition according to [10] or [11], wherein the mass of the component (1) is relative to the mass of the component (1) and the component (5) [ingredient (1) / (ingredient (1) + component (5))] is 0.001 to 1.0.

[13] The one-component epoxy resin composition according to any one of [5] to [12] wherein the epoxy equivalent of the epoxy resin of the component (2) is contained in the component (1) The total equivalent of the thiol group [the total number of thiol groups equivalents / the number of epoxy equivalents) is 0.2 to 2.0.

[14] The one-component epoxy resin composition according to any one of [10] to [12], wherein the epoxy equivalent of the epoxy resin of the component (2), the component (1) and the component ( 5) The total equivalent of the thiol group contained in the thiol group (the total number of thiol groups / the number of epoxy equivalents) is 0.2 to 2.0.

[15] A cured epoxy resin obtained by heating the one-component epoxy resin composition according to any one of [5] to [14].

The novel thiol group-containing compound of the present invention can harden an epoxy resin. Further, a resin comprising a novel thiol group-containing compound of the present invention is prepared by combining a curing agent with a component (2) and optionally a component (3), a component (4) and/or (5). By this, it is possible to obtain a one-liquid epoxy resin composition which exhibits low-temperature-speed hardenability and is excellent in storage stability.

[Best Mode for Carrying Out the Invention] [compound containing thiol group]

The thiol group-containing compound of the present invention is represented by the formula (1).

Formula 1):

(In the formula (1), R represents a hydrogen atom, a hydrocarbon group which may have a substituent, or -CH ₂ -OC(O)-[CH ₂ ] _l -SH (l represents an integer of 1 to 8, and It is preferably an integer of 1 to 6, more preferably an integer of 2 to 4. It is preferably a hydrogen atom or a saturated or unsaturated linear or branched hydrocarbon group which may have a substituent, and is preferably a hydrogen atom. Or a linear or branched hydrocarbon group having a saturated or unsaturated saturated carbon number of 1 to 30, which may have a substituent.

The R system is more preferably a hydrogen atom or a saturated or unsaturated linear or branched hydrocarbon group having 1 to 15 carbon atoms, more preferably a hydrogen atom or a saturated or unsaturated linear chain having 1 to 6 carbon atoms or A branched hydrocarbon group is particularly preferably a hydrogen atom or a saturated or unsaturated linear or branched hydrocarbon group having 1 to 4 carbon atoms. Further preferred is a saturated linear hydrocarbon group.

Examples of the hydrocarbon group which may have a substituent include a methyl group, an ethyl group, an isopropyl group, a propyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a sec-pentyl group. Tert-pentyl, isopentyl, hexyl, heptyl, octyl, 2-ethylhexyl, tert-octyl, decyl, isodecyl, fluorenyl, isodecyl, eleven, twelfth, Tertiary, isotridecyl, tetradecyl, fifteen, and the substituents containing such substituents.

In the formula (1), the X and Z groups each independently represent a divalent aliphatic hydrocarbon group which may have a substituent. The divalent aliphatic hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group, and the number of carbon atoms is preferably from 1 to 20, more preferably from 1 to 10, still more preferably from 2 to 6. The number of carbon atoms of the substituent is not included in the above carbon number.

The divalent aliphatic hydrocarbon group may, for example, be an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a cycloalkenyl group, an alkenelenylene group or an alkylene group. Diacetylene Alkadiynylene), alkalynynylene, etc., preferably an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group. Therefore, in a preferred embodiment, the X and Z groups are each independently a divalent alkylene group having 1 to 20 carbon atoms which may have a substituent. Further preferably, they are each independently a divalent alkylene group having 1 to 20 carbon atoms.

Examples of the above alkylene group include a methylene group, an ethylidene group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, a decyl group, a hydrazine group, a hydrazine group, and a stretching group. Undecyl, dodecyl, thirteen, alkyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, Alkyl and the like.

Y series means selected from -OC(O)-, -C(O)O-, -NHC(O)-, -C(O)NH-, -SC(O)-, and -C(O)S- Divalent base. The Y system is preferably selected from the group consisting of -OC(O)-, -C(O)O-, -SC(O)-, and -C(O)S-, and is preferably selected from -SC. The divalent group of (O)- and -C(O)S-.

The m system represents an integer from 1 to 8. Further preferably, it is an integer of 1 to 6, more preferably an integer of 2 to 4.

The n system represents an integer from 1 to 8. Further preferably, it is an integer of 1 to 6, more preferably an integer of 2 to 4.

In the present specification, the term "substituent" means, unless otherwise specified, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkyloxy group, an aryl group or an aryloxy group. An arylalkyl group, an arylalkoxy group, a monovalent heterocyclic group, an amine group, a decyl group, a decyl group, a decyloxy group, a carboxyl group, a cyano group, a nitro group, a hydroxyl group, a fluorenyl group and an oxo group.

As the halogen atom to be used as a substituent, For example: a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The alkyl group used as a substituent may be either linear or branched. The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 14 carbon atoms, still more preferably 1 to 12 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 3 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.壬 base, and 癸 base. As described later, an alkyl group which is used as a substituent may further have a substituent ("secondary substituent"). The alkyl group having a related secondary substituent may, for example, be an alkyl group substituted with a halogen atom, and specific examples thereof include a trifluoromethyl group, a trichloromethyl group, a tetrafluoroethyl group, a tetrachloroethyl group, and the like. .

The number of carbon atoms of the cycloalkyl group to be used as a substituent is preferably from 3 to 20, more preferably from 3 to 12, still more preferably from 3 to 6. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group.

The alkoxy group used as a substituent may be either linear or branched. The alkoxy group preferably has 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, an isobutoxy group, a tert-butoxy group, and a pentyloxy group. Base, hexyloxy, heptyloxy, octyloxy, decyloxy, and decyloxy.

The number of carbon atoms of the cycloalkyloxy group to be used as a substituent is preferably from 3 to 20, more preferably from 3 to 12, still more preferably from 3 to 6. Examples of the cycloalkyloxy group include a cyclopropoxy group, a cyclobutoxy group, and a cyclopentane group. Oxyl, and cyclohexyloxy.

The aryl group used as a substituent is a group obtained by removing one hydrogen atom on an aromatic ring from an aromatic hydrocarbon. The number of carbon atoms of the aryl group used as a substituent is preferably from 6 to 24, more preferably from 6 to 18, still more preferably from 6 to 12. Examples of the aryl group include a phenyl group, a naphthyl group, and an anthracenyl group.

The number of carbon atoms of the aryloxy group used as a substituent is preferably from 6 to 24, more preferably from 6 to 18, still more preferably from 6 to 12. Examples of the aryloxy group to be used as a substituent include a phenoxy group, a 1-naphthyloxy group, and a 2-naphthyloxy group.

The number of carbon atoms of the arylalkyl group to be used as a substituent is preferably from 7 to 25, more preferably from 7 to 19, still more preferably from 7 to 13. Examples of the arylalkyl group include a phenyl-C1 to C12 alkyl group, a naphthalene-C1 to C12 alkyl group, and a fluorene-C1 to C12 alkyl group.

The number of carbon atoms of the arylalkoxy group to be used as a substituent is preferably from 7 to 25, more preferably from 7 to 19, still more preferably from 7 to 13. Examples of the arylalkoxy group include a phenyl-C1 to C12 alkoxy group and a naphthalene-C1 to C12 alkoxy group.

The monovalent heterocyclic group used as a substituent means a group obtained by removing one hydrogen atom on a heterocyclic ring from a heterocyclic compound. The monovalent heterocyclic group preferably has 3 to 21 carbon atoms, more preferably 3 to 15 carbon atoms, still more preferably 3 to 9 carbon atoms. A monovalent aromatic heterocyclic group (heteroaryl) may also be included in the monovalent heterocyclic group. Examples of the monovalent heterocyclic ring include a thienyl group, a pyrrolyl group, a furyl group, a pyridyl group, and an anthracene. Base, pyrimidinyl, pyridyl Base, three A pyrrolidinyl group, a piperidinyl group, a quinolyl group, and an isoquinolyl group.

The amine group to be used as a substituent may be any of a linear or branched aliphatic group or an aromatic group. The number of carbon atoms of the amine group is preferably from 1 to 20, preferably from 1 to 12, more preferably from 1 to 6. Examples of the amine group include an aminomethyl group, an aminoethyl group, an aminopropyl group, an isopropylamine group, an aminobutoxy group, a sec-butylamino group, an isobutylamino group, and a tert-butylamine group. An aminopentyl group, an aminohexyl group, an aminoheptyl group, an aminooctyl group, an amine fluorenyl group, an amine fluorenyl group, an aminophenyl group, and the like.

The alkyl group to be used as a substituent may be any of a linear chain or a branched chain. The alkylene group preferably has 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms. Examples of the decylalkyl group include methylmercaptoalkyl group, ethylmercaptoalkyl group, propylmethylidene alkyl group, isopropylformamidinyl group, butoxymethyl sulfonyl group, sec-butyl formalyl group, and isobutyl formane. Base, tert-butylformamidinyl, amylforminyl, hexylmethyl decyl, heptylmethyl decyl, octyl decylalkyl, fluorenyl decyl, and fluorenyl decyl.

The thiol group used as a substituent is a group represented by the formula: -C(=O)-R1 (wherein R1 is an alkyl group or an aryl group). The alkyl group represented by R1 may be either linear or branched. Examples of the aryl group represented by R1 include a phenyl group, a naphthyl group, and an anthracenyl group. The carbon number of the fluorenyl group is preferably from 2 to 20, more preferably from 2 to 13, more preferably from 2 to 7. Examples of the fluorenyl group include an ethyl fluorenyl group, a propyl fluorenyl group, a butyl fluorenyl group, an isobutyl fluorenyl group, a trivalyl group, and a benzamidine group.

The methoxy group used as a substituent is called a formula: a group represented by -O-C(=O)-R2 (wherein R2 is an alkyl group or an aryl group). The alkyl group represented by R2 may be either linear or branched. Examples of the aryl group represented by R2 include a phenyl group, a naphthyl group, and an anthracenyl group. The number of carbon atoms of the decyloxy group is preferably from 2 to 20, more preferably from 2 to 13, more preferably from 2 to 7. Examples of the decyloxy group include an ethoxycarbonyl group, a propenyloxy group, a butoxy group, an isobutyloxy group, a pivaloyloxy group, and a benzhydryloxy group.

The thiol group-containing compound of the present invention, wherein R is a hydrogen atom or a saturated or unsaturated linear or branched hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 6 carbon atoms, in the formula (1), The X and Z series independently represent a divalent alkylene group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and Y is -SC(O)- or -C(O)S-, m. It is an integer from 2 to 4, and n is an integer from 2 to 4.

Further, as the thiol group-containing compound of the present invention, a structural formula having the following formula (2) is particularly preferred: 2-ethyl-2-{{{3-[(3-mercaptopropyl)sulfide] Propionyl}oxy}methyl}propane-1,3-diylbis(3-mercaptopropionate).

[hardener for epoxy resin]

The thiol group-containing compound of the present invention can be used as a curing agent for an epoxy resin because it can harden an epoxy resin. In this case, it is preferred to adjust the total equivalent amount of the thiol groups (the total number of thiol groups/epoxy equivalents) to 0.2 to 2.0, and preferably 0.6 to 1.2, based on the epoxy equivalent of the epoxy resin. . Here, the epoxy equivalent means the mass of the epoxy resin containing one equivalent of the epoxy group, and can be measured, for example, according to JIS K 7236 (2009). The thiol group total equivalent means the mass of the thiol group-containing compound containing 1 equivalent of a thiol group.

The curing agent for an epoxy resin of the present invention may contain the above-described thiol group-containing compound of the present invention, and may further contain an imidazole or an amine as another component. The curing agent for the epoxy resin may contain other components in an amount of, for example, 0.01 to 10% by mass, preferably 0.1 to 5% by mass.

[Single liquid epoxy resin composition]

The one-component epoxy resin composition of the present invention contains at least the above compound (component (1)) and an epoxy resin (component (2)) having two or more epoxy groups in the molecule. The one-liquid epoxy resin composition of the present invention preferably contains a solid dispersion type latent curing accelerator (component (3)) arbitrarily. Furthermore, the one-component epoxy resin composition of the present invention preferably optionally contains the component (4) and/or the component (5); the component (4): selected from the group consisting of a boronic acid ester compound, a titanate compound, and aluminum. One or more of an acid salt compound, a zirconate compound, an isocyanate compound, a carboxylic acid, an acid anhydride, and a mercapto organic acid; and the component (5): different from the component (1) in the molecule A compound having two or more thiol groups, that is, a compound having two or more thiol groups in the molecule and having no hydroxyl group in the molecule. By containing such a component, the one-liquid epoxy resin composition of the present invention can have both low-temperature quick-curing property and storage stability.

In addition, when the content of the epoxy resin of the component (2) is 100 parts by mass, the content of the thiol group-containing compound of the component (1) is preferably 0.1 to 100 parts by mass, preferably 1 ~98 parts by mass, more preferably 5 to 95 parts by mass.

. Ingredients (2)

The epoxy resin of the component (2) used in the present invention may be any one having two or more epoxy groups per molecule. For example, polyhydric water obtained by reacting a polyhydric phenol such as bisphenol A, bisphenol F, bisphenol AD, catechol or resorcin, or a polyhydric alcohol such as glycerin or polyethylene glycol with epichlorohydrin may be mentioned. a glyceryl ether; a glycidyl ether ester obtained by reacting a hydroxycarboxylic acid such as p-hydroxybenzoic acid or β-hydroxynaphthoic acid with epichlorohydrin; and a polycarboxylic acid such as phthalic acid or terephthalic acid. Polyglycidyl ester obtained by reaction with epichlorohydrin; further, such as epoxidized phenol phenolic resin, epoxidized cresol novolac resin, epoxidized polyolefin, cyclic aliphatic epoxy resin, other modified urethane modified ring Oxygen resin or the like, but is not limited to these.

Specifically, as the epoxy resin of the component (2), among these, bisphenol A type epoxy resin and bisphenol F type ring are preferable from the viewpoint of maintaining high heat resistance and low moisture permeability. Oxygen resin, phenol novolak type epoxy resin, biphenyl aralkyl type epoxy resin, phenol aralkyl type epoxy resin, aromatic Aromatic glycidylamine type epoxy resin, epoxy resin having a dicyclopentadiene structure, etc., preferably a bisphenol A type epoxy resin and a bisphenol F type epoxy resin, and a bisphenol A type ring An oxy resin is preferred.

The epoxy resin of the component (2) may be in a liquid state or a solid shape, and both a liquid form and a solid shape may be used. Here, the "liquid" and "solid shape" mean the state of the epoxy resin at normal temperature (25 ° C). From the viewpoint of coatability, workability, and adhesion, it is preferred that at least 10% by mass or more of the entire epoxy resin used is liquid. Specific examples of the liquid epoxy resin include liquid bisphenol A type epoxy resin ("EPIKOTE 828EL", "EPIKOTE 827", manufactured by Mitsubishi Chemical Corporation), and liquid bisphenol F type epoxy resin. ("EPIKOTE 807" manufactured by Mitsubishi Chemical Corporation), naphthalene type 2-functional epoxy resin ("HP4032" manufactured by DIC Corporation, "HP4032D"), liquid bisphenol AF epoxy resin (Dongdu Chemical Co., Ltd.) "ZX1 O59"), an epoxy resin having a hydrogenated structure ("EPIKOTE YX8000" manufactured by Mitsubishi Chemical Corporation). Among them, "EPIKOTE 828EL", "EPIKOTE 827", and "EPIKOTE 807" manufactured by Mitsubishi Chemical Corporation, which is high in heat resistance and low in viscosity, are preferably "EPIKOTE 828EL". Moreover, as a specific example of the solid epoxy resin, a naphthalene type tetrafunctional epoxy resin ("HP4700" manufactured by DIC Co., Ltd.) and a dicyclopentadiene type polyfunctional epoxy resin (made by DIC) can be exemplified. HP7200"), naphthol type epoxy resin ("ESN-475V" manufactured by Tohto Kasei Co., Ltd.), epoxy resin having a butadiene structure ("PB-3600" manufactured by DAICEL Chemical Industry Co., Ltd.), and Epoxy resin of phenyl structure ("NC3000H" made by Nippon Kayaku Co., Ltd., "NC3000L", "YX4000" manufactured by Mitsubishi Chemical Corporation).

When the mass of the entire resin composition of the present invention is 100% by mass, the content of the epoxy resin of the component (2) is preferably, for example, 5% by mass or more, more preferably 10% by mass or more, and still more preferably 20% by mass. The mass% or more is more preferably 30% by mass or more, particularly preferably 40% by mass or more, and particularly preferably 45% by mass or more. Further, it is preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less, still more preferably 80% by mass or less, still more preferably 75% by mass or less, and particularly preferably 70% by mass or less. Below mass%.

. Ingredients (3)

The solid dispersion type latent hardening accelerator of the component (3) used in the present invention means a solid which is insoluble in the component (2) (epoxy resin) at room temperature (25 ° C), and is heated by heating. The compound which can be dissolved and acts as a hardening accelerator for an epoxy resin can be, for example, a solid imidazole compound at room temperature and a solid dispersion type amine adduct latent curing accelerator, but is not limited thereto. in. As an example of the latent amine-additive latent curing accelerator, a reaction product of an amine compound with an epoxy compound (amine-epoxy adduct), an amine compound and an isocyanate compound or a urea compound can be exemplified. A product (urea type adduct system) or the like. Among these, a solid dispersion type amine adduct is preferably a latent curing accelerator.

Examples of the imidazole compound which is solid at normal temperature include, for example, 2-heptadecylimidazole and 2-phenyl-4,5-dihydroxymethylimidazole. 2-undecylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4-benzyl-5-hydroxymethylimidazole, 2,4-diamino- 6-(2-methylimidazolyl-(1))-ethyl-S-triazine, 2,4-diamino-6-(2'-methylimidazolyl-(1)')-ethyl -S-triazine. Isocyanuric acid adduct, 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2 -methylimidazole-p-benzoic acid ester, 1-cyanoethyl-2-phenylimidazole-p-benzoic acid ester, N-(2-methylimidazolyl-1-ethyl)-urea, N,N '-(2-methylimidazolyl-(1)-ethyl)-hexamethylenediamine or the like, but is not limited thereto.

The epoxy compound which is one of the raw materials for the production of the solid dispersion type amine addition type latent curing accelerator (amine-epoxy adduct system), for example, bisphenol A, bisphenol F, a polyglycidyl ether obtained by reacting a polyhydric phenol such as catechol or resorcin, or a polyhydric alcohol such as glycerin or polyethylene glycol with epichlorohydrin; and p-hydroxybenzoic acid, β-hydroxynaphthoic acid a glycidyl ether ester obtained by reacting a hydroxycarboxylic acid with epichlorohydrin; a polyglycidyl ester obtained by reacting a polycarboxylic acid such as phthalic acid or terephthalic acid with epichlorohydrin; a glycidylamine compound obtained by reacting with epichlorohydrin such as 4'-diaminodiphenylmethane or m-amine phenol; and further, such as an epoxidized phenol phenolic resin, an epoxidized cresol novolac resin, an epoxidized polyolefin, etc. The monofunctional epoxy compound such as a polyfunctional epoxy compound, butyl glycidyl ether, phenyl glycidyl ether or glycidyl methacrylate is not limited thereto.

The amine compound to be used as a raw material for producing the latent solid amine-based amine-based latent curing accelerator is one having at least one active hydrogen which can react with an epoxy group in the molecule, and at least in the molecule. It is sufficient to have one or more functional groups selected from the group consisting of a primary amine group, a secondary amine group, and a tertiary amine group. As such an amine compound, for example, diethylenetriamine, triethylenetetramine, n-propylamine, 2-hydroxyethylaminopropylamine, cyclohexylamine, 4,4'-diamine can be mentioned. An aliphatic amine such as bis-cyclohexylmethane; an aromatic amine compound such as 4,4'-diaminodiphenylmethane or 2-methylaniline; 2-ethyl-4-methylimidazole; 2-ethyl-4-methylimidazoline, 2,4-dimethylimidazoline, piperidine, piperidine The heterocyclic compound or the like containing a nitrogen atom is not limited thereto.

Further, among them, a compound having a tertiary amino group in the molecule, which is a raw material which provides a latent hardening accelerator having excellent hardening-promoting ability, and examples of such a compound include, for example, dimethylamine. Propylamine, diethylaminopropylamine, di-n-propylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, N-methylper An amine compound, or an imidazole compound such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole or 2-phenylimidazole, which has a tertiary amino group in the molecule. Grade 1 or 2 amines; 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2-dimethylaminoethanol, 2- Diethylaminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, 1-(2-hydroxy-3-phenoxypropyl)-2-methylimidazole, 1-(2 -hydroxy-3-phenoxypropyl)-2-ethyl-4-methylimidazole, 1-(2-hydroxy-3-butoxypropyl)-2-methylimidazole, 1-(2- Hydroxy-3-butoxypropyl)-2-ethyl-4-methylimidazole, 1-(2-hydroxy-3-phenoxypropyl)-2-phenylimidazoline, 1-(2- Hydroxy-3-butoxypropyl)-2-methylimidazoline, 2-(dimethylaminomethyl)phenol, 2,4,6-gin(dimethylaminomethyl)phenol, N -β-hydroxyethyl orfolin, 2-dimethylaminoethanethiol, 2-mercaptopyridine, 2-benzimidazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 4-mercaptopyridine , N,N-dimethylaminobenzoic acid, N,N-dimethylglycine, nicotinic acid, isonicotinic acid, 2-picolinic acid, N,N-dimethyl Alcohols, phenols, etc. having a tertiary amino group in the molecule, such as guanyl glycinate, N,N-dimethylpropionate, nicotinic acid bismuth, isonianic acid bismuth or the like Mercaptans, carboxylic acids and terpenes.

When the above-mentioned epoxy compound and the amine compound are subjected to an addition reaction to produce a latent curing accelerator, an active hydrogen compound having two or more active hydrogens in the molecule may be further added. Examples of the active hydrogen compound include polyphenols such as bisphenol A, bisphenol F, bisphenol S, hydroquinone, catechol, resorcin, pyrogallol, and phenol novolac. Polyols such as trimethylolpropane, polyvalent carboxylic acids such as adipic acid and phthalic acid, 1,2-dimercaptoethane, 2-mercaptoethanol, 1-mercapto-3-phenoxy- 2-propanol, thioglycolic acid, ortho-amino acid, lactic acid, and the like, but are not limited thereto.

An isocyanate compound which is used as a raw material for producing the solid dispersion type amine addition type latent curing accelerator, for example, a monofunctional isocyanate compound such as n-butyl isocyanate, isopropyl isocyanate, phenyl isocyanate or benzyl isocyanate ; hexamethylene diisocyanate, tolylene diisocyanate, 1,5-naphthalene diisocyanate, diphenylmethane-4,4'-diisocyanate, isophorone diisocyanate, xylene diisocyanate , p-phenyl diisocyanate, 1,3,6-six A polyfunctional isocyanate compound such as methylene triisocyanate or bicycloheptane triisocyanate; and a terminal isocyanate group-containing compound obtained by a reaction between a polyfunctional isocyanate compound and an active hydrogen compound. As an example of such a compound containing a terminal isocyanate group, an addition compound having a terminal isocyanate group obtained by reacting methylphenyl diisocyanate with trimethylolpropane, by methylphenyl diisocyanate, and The addition compound having a terminal isocyanate group obtained by the reaction of pentaerythritol is not limited thereto.

In addition, examples of the urea compound to be used as a raw material for producing the latent solid amine-based amine-based latent curing accelerator include urea, thiourea, and the like, but are not limited thereto.

The solid dispersion type latent hardening accelerator of the component (3) can be cooled and solidified by, for example, appropriately mixing the above-mentioned raw materials, and reacted at room temperature to 200 ° C, followed by pulverization or pulverization. It is reacted in a solvent such as methyl ethyl ketone, dioxane or tetrahydrofuran, and after the solvent is removed, the solid fraction is pulverized and can be easily obtained.

A commercially available representative example of the solid dispersion type latent curing accelerator of the component (3), for example, an amine-epoxy adduct system (amine addition system), for example, "AMICURE PN-23" (Ajumimoto PN-H) (Ajurimoto PN-H) (Hardosin X-3661S) (ACR (share) brand name), "HARDENER X-3670S" ( ACR (share) product name), "NOVACURE HX-3742" (Asahi Kasei (share) product name), "NOVACURE HX-3721" (Asahi Kasei (share) product name), etc. In addition, as the urea-type adduct system, "FUJICURE FXE-1000" (Fuji Kasei Co., Ltd. product name) and "FUJICURE FXR-1030" (Fuji Kasei Co., Ltd.) may be exemplified, but it is not limited thereto. in.

When the content of the epoxy resin of the component (2) is 100 parts by mass, the content of the solid dispersion type latent curing accelerator of the component (3) is preferably 0.1 to 100 parts by mass, more preferably 1 to 1 part. 60 parts by mass, more preferably 5 to 30 parts by mass.

. Ingredients (4)

In order to achieve superior storage stability, the composition of the present invention preferably further contains a compound selected from the group consisting of a boronic acid ester compound, a titanate compound, an aluminate compound, a zirconate compound, an isocyanate compound, a carboxylic acid, and an acid anhydride. One or more kinds of sulfhydryl organic acids (ingredient (4)).

Examples of the boric acid ester compound include trimethyl borate, triethyl borate, tri-n-propyl borate, triisopropyl borate, tri-n-butyl borate, triamyl borate, triallyl borate, and the like. Trihexyl borate, tricyclohexyl borate, trioctyl borate, tridecyl borate, tridecyl borate, tri-dodecyl borate, tri-hexadecane borate, tri-octadecyl borate,参(2-ethylhexyloxy)borane, bis(1,4,7,10-tetraoxaundecyl)(1,4,7,10,13-pentaoxatetradecyl) (1,4,7-trioxadecyl)borane, tribenzyl borate, triphenyl borate, tri-o-tolyl borate, tri-m-cresyl borate, triethanolamine boric acid Ester and the like.

Examples of the titanate compound include tetraethyl titanate, tetrapropyl titanate, tetraisopropyl titanate, tetrabutyl titanate, and titanic acid. Tetraoctyl ester and the like.

Examples of the aluminate compound include triethyl aluminate, tripropyl aluminate, triisopropylaluminate, tributyl aluminate, and trioctyl aluminate.

Examples of the zirconate compound include tetraethyl zirconate, tetrapropyl zirconate, tetraisopropyl zirconate, and tetrabutyl zirconate.

Examples of the isocyanate compound include n-butyl isocyanate, isopropyl isocyanate, 2-chloroethyl isocyanate, phenyl isocyanate, p-chlorophenyl isocyanate, benzyl isocyanate, hexamethylene diisocyanate, and 2 -ethylphenylisocyanate, 2,6-dimethylphenylisocyanate, 2,4-toluene diisocyanate, methylphenylene diisocyanate, 2,6-toluene diisocyanate, 1,5-naphthalene diisocyanate, Phenylmethane-4,4'-diisocyanate, di-toluidine diisocyanate, isophorone diisocyanate, xylene diisocyanate, p-phenyl diisocyanate, bicycloheptane triisocyanate, and the like.

Examples of the carboxylic acid include saturated aliphatic monobasic acids such as formic acid, acetic acid, propionic acid, butyric acid, caproic acid, and caprylic acid, and unsaturated aliphatic monobasic acids such as acrylic acid, methacrylic acid, and crotonic acid, and monochlorobenzene. Halogenated fatty acid such as acetic acid or dichloroacetic acid, monovalent oxyacid such as glycolic acid or lactic acid, aliphatic aldehyde acid such as glyoxylic acid or racemic tartaric acid, and keto acid, oxalic acid, malonic acid, succinic acid An aromatic monobasic acid, phthalic acid, trimesic acid such as aliphatic polybasic acid such as maleic acid, benzoic acid, halogenated benzoic acid, toluic acid, phenylacetic acid, cinnamic acid or mandelic acid Such as aromatic polybasic acids.

Examples of the acid anhydride include succinic anhydride, dodecenyl succinic anhydride, maleic anhydride, an adduct of methylcyclopentadiene and maleic anhydride, hexahydrophthalic anhydride, and methyltetrahydrogen. An aromatic polybasic acid anhydride such as an aliphatic or aliphatic polybasic acid anhydride such as phthalic anhydride or phthalic anhydride, trimellitic anhydride or pyromellitic dianhydride.

Examples of the mercapto organic acid include mercapto aliphatic monocarboxylic acids such as mercaptoacetic acid, mercaptopropionic acid, mercaptobutyric acid, mercaptosuccinic acid, and dimercaptosuccinic acid, and esterification of a hydroxy organic acid with a mercapto organic acid. The obtained mercapto aliphatic monocarboxylic acid, mercapto aromatic monocarboxylic acid such as mercaptobenzoic acid, or the like.

As a component (4), it is highly versatile. From the viewpoint of safety and improvement in storage stability, a borate compound is preferred, and triethyl borate, tri-n-propyl borate, triisopropyl borate, tri-n-butyl borate, and the like are preferred. Preferably, it is triethyl borate. The content of the component (4) is not particularly limited as long as it can improve the storage stability of the resin, but when the content of the epoxy resin of the component (2) is 100 parts by mass, the component (4) The content of the compound is preferably 0.001 to 50 parts by mass, more preferably 0.05 to 30 parts by mass, still more preferably 0.1 to 10 parts by mass.

As a method of blending the epoxy resin composition of the present invention with respect to the component (4), in addition to the simultaneous blending with the components of the components (1) to (3), the solid dispersion type of the component (3) may be previously The hardening accelerator is mixed with the component (4). As a mixing method at this time, it may be in a solvent such as methyl ethyl ketone toluene or the like, or in a liquid epoxy resin. Or in the absence of a solvent, by bringing the two into contact.

. Ingredients (5)

In addition to the above-mentioned composition, from the viewpoint of low-temperature curability, it is preferred to formulate a compound (component (5)) having two or more thiol groups in the molecule different from the component (1).

Examples of the compound having two or more thiol groups in the molecule include, for example, trimethylolpropane (3-mercaptopropionate), trimethylolpropane (mercaptoacetate), and neopentyl Alcohol oxime (mercaptoacetate), ethylene glycol dimercaptoacetate, trimethylolpropane ginseng (β-mercaptopropionate), neopentyl quinone oxime (β-mercaptopropionate), dioxane A thiol compound obtained by esterification of a polyol such as tetraol poly(β-mercaptopropionate) with a mercapto organic acid. From the viewpoint of preserving stability, it is preferred that the content of the basic impurity is small, and a user who does not need an alkaline substance in production, for example, trimethylolpropane ginseng (3-mercaptopropionate) is used. Preferably.

Further, as a compound having two or more thiol groups in the molecule different from the component (1), for example, 1,4-butanedithiol, 1,6-hexanedithiol, 1,10-decanedisulfide An alkyl polythiol compound such as an alcohol; a polyether having a terminal thiol group; a polythioether having a terminal thiol group; a thiol compound obtained by reacting an epoxy compound with hydrogen sulfide; and a polythiol a thiol compound having a terminal thiol group obtained by reacting a compound with an epoxy compound; and thus, a basic substance can be used as a reaction catalyst in the production step, but desalting treatment is preferably carried out, and an alkali metal is used. The ion concentration was set to 50 ppm or less.

A polythiol compound produced by using a basic substance as a reaction catalyst, and a method for de-alkali treatment of the polythiol compound, for example, a polythiol compound to be treated is dissolved in an organic solvent such as acetone or methanol. After neutralization by adding acid such as dilute hydrochloric acid or dilute sulfuric acid, via extraction. A method of washing or the like, a method of adsorbing by using an ion exchange resin, a method of purifying by distillation, or the like, but is not limited thereto.

When the content of the epoxy resin of the component (2) is 100 parts by mass, the content of the component (5) is preferably 20 to 100 parts by mass, more preferably 30 to 90 parts by mass, still more preferably 45 to 45 parts by mass. 80 parts by mass.

In the present invention, when the component (5) is used, the mass of the component (1) relative to the mass of the component (1) and the component (5) [ingredient (1) / (component (1) + component (5))]] It is preferably 0.001 to 1.0. The lower limit is preferably 0.01, 0.03, or 0.1. The upper limit is not particularly limited, but is preferably 1.0, 0.95, and 0.9.

The total equivalent of the thiol group (the total number of thiol groups/epoxy equivalents) of the thiol group contained in the component (1) and the component (5) with respect to the epoxy equivalent of the epoxy resin of the component (2) is preferably It is set to 0.2 to 2.0, and preferably set to 0.4 to 1.6, and more preferably set to 0.6 to 1.2.

The component (1) and the component (2) described above, and the components of the component (3), the component (4) and the component (5) of any component are used as raw materials to prepare the one-component epoxy resin of the present invention. The composition is not particularly difficult to carry out according to a conventionally known method. For example, a mixer such as a Henschel mixer (HENSCHEL MIXER) can be used to mix each The composition is used to prepare the one-component epoxy resin composition of the present invention.

Further, the single-liquid epoxy resin composition obtained by curing is not particularly difficult, and this can also be carried out according to a conventionally known method. For example, the single-liquid epoxy resin composition obtained by heating can be hardened. The heating system is, for example, at a temperature of 70 to 150 ° C, preferably 75 to 120 ° C, and more preferably 80 to 100 ° C, for example, 1 to 60 minutes, preferably 3 to 30 minutes, and more preferably 5 to 5 15 minutes to proceed as appropriate. In particular, by heating at 80 ° C or 100 ° C for 10 minutes or less, if it is possible to cure, it can be judged to have moderate low-temperature-speed hardenability.

In the single-liquid epoxy resin composition of the present invention, a filler, a diluent, a solvent, a pigment, a flexibility imparting agent, a coupling agent, an antioxidant, and a thixotropic property which are commonly used in the field of the present invention can be added as needed. Various additives such as a dispersing agent and a dispersing agent are added.

In the present invention, the cured epoxy resin obtained by heating the above-mentioned single-liquid epoxy resin composition, and a functional product containing the cured epoxy resin are also included. Examples of the functional product include an adhesive, an injection molding agent, a sealant, a sealant, a fiber-reinforced resin, a coating agent, and a paint.

[Examples]

Hereinafter, the present invention will be more specifically described based on examples, but the present invention is not limited to the following examples. In addition, the "parts" in the following description means "parts by mass".

<Synthesis Example 1>

2-Ethyl-2-{{{3-[(3-mercaptopropyl)sulfanyl]propenyl}oxy}methyl}propane-1,3- of the thiol group-containing compound of the present invention Dikis bis(3-mercaptopropionate) was prepared in the following manner.

That is, first, 800 g (5.96 mol) of 1,1,1-paraxyl (hydroxymethyl)propane, 569.6 g (5.37 mol) of 3-mercaptopropionic acid, and 8.0 g of p-toluenesulfonic acid monohydrate were added to the reaction vessel ( 4.21 mmol) and stirred. After confirming the reaction, the obtained reactant was dissolved in 8 L of acetone, and 40 g (21.05 mmol) of p-toluenesulfonic acid monohydrate was added and stirred to obtain a crude product. The obtained crude product was further purified through a hydrazine gel column, and one thiol group was introduced to obtain a compound protected by two hydroxy groups.

Next, 314.1 g (0.90 mol) of 3-mercaptopropionic acid protected with trityl group, 600 ml of acetonitrile, N-methylimidazole (201.8 g, 2.46 mol) were added to the obtained compound, and stirred to obtain a crude product. product. The obtained crude product is further purified by a hydrazine gel column to obtain a thioesterified compound.

Further, to 400 g (675 mmol) of the obtained compound, 1.5 L of methanol and 267 ml of water were added, and further 41 ml of hydrochloric acid was added thereto and stirred to carry out deprotection of a hydroxyl group to obtain 380 g of a crude product. To the obtained crude product, 189 g (543 mmol) of 3-mercaptopropionic acid protected with trityl group, 350 ml of acetonitrile, N-methylimidazole (134 g, 1.63 mol) were added and stirred, and then kept at 0-5 ° C ( At an average of 3 ° C), in a solution of 500 ml of acetonitrile, a solution of 124 g (651 mmol) dissolved in tosyl chloride was added dropwise. liquid. The obtained crude product is purified by a hydrazine gel to obtain a purified compound in which a thiol group is introduced into a residual hydroxyl group.

Among the above-mentioned compounds, tritr-acetic acid was added to carry out de-tritylation, and the crude product obtained by de-tritification was subjected to hydrazine gel purification to obtain 94 g of the object (2-ethyl-2). -{{{3-[(3-Mercaptopropyl)thio]propanyl}oxy}methyl}propane-1,3-diylbis(3-mercaptopropionate)). The NMR data of the obtained object was as follows.

1H-NMR (400MHz, CDCL3, rt): δ4.07 (6H, s), 3.14 (2H, t), 2.90-2.60 (14H, m), 1.70-1.50 (5H, m), 0.90 (3H, t ), ESI-MS (positive): m/z 487 [M+H]+

The abbreviation of the raw materials used in the examples is as follows.

Ingredients (2): Epoxy resin: "EPIKOTE 828EL" (trade name of Mitsubishi Chemical Corporation); bisphenol A epoxy resin epoxy equivalent 184~194

Ingredient (5): Polythiol compound: "TMTP" (trade name of Sigma-Aldrich); Trimethylolpropane ginseng (3-mercaptopropionate)

Ingredient (3): Solid dispersion type hardening accelerator: "AMICURE PN-23" (Ajinomoto Fine-Techno company trade name)

Additive: Thixotropy-imparting agent: cerium oxide micro-powder "AEROSIL 200" (Japan AEROSIL Co., Ltd.)

Modulation method of Embodiments 1 to 5

To the bisphenol A type epoxy resin "EPIKOTE 828EL", triethyl borate was mixed, and the specific amount shown in the formulation of Table 1 was added thereto, and the object of the present invention (2-ethyl-2) was added thereto. -{{{3-[(3-Mercaptopropyl)thio]propanyl}oxy}methyl}propane-1,3-diylbis(3-mercaptopropionate) and "TMTP", And mix evenly. Finally, "AMICURE PN-23" and a thixotropy fine powder "AEROSIL 200", which was added with a thixotropic agent, were sufficiently stirred to prepare a uniform single-liquid epoxy resin composition. The blending amount and the evaluation results are shown in Table 1.

(evaluation method) [Gelification time measurement test]

According to JIS C6521, the single-liquid epoxy resin composition obtained in the examples was measured at 80 ° C and 100 ° C by a hot plate gelation tester (GT-D: manufactured by Nisshin Scientific Co., Ltd.). Time (refer to Table 80 "80 ° C (seconds)" and "100 ° C (seconds)"). Specifically, 0.5 g of the one-component epoxy resin composition was placed on a hot plate of the above-described hot plate type gelation tester adjusted to a measurement temperature of 80 ° C or 100 ° C, and the time point of the placement was taken as a At the beginning, the single-liquid epoxy resin composition was contacted on a hot plate in a range of 25 mm in diameter, and the resin composition was repeatedly contacted with a spatula having a tip width of 5 mm (one rotation per second). In a circular motion, the single-liquid epoxy resin composition is vertically pulled up from the heating plate by 30 mm, and the time from the start point to the end point is regarded as gelation when the filament is to be cut. When The measurement was performed between. The measurement was repeated 3 times and the average value thereof was used. (Refer to "80 °C evaluation" and "100 °C evaluation" in Table 1).

The time until the gelation was 5 minutes or less was evaluated as ○; the 15 minute or less was evaluated as Δ; and over 15 minutes, the evaluation was ×. When the measurement temperature is 80 ° C or 100 ° C, if it is hardenable for 15 minutes or less, it is judged to have low-temperature rapid hardenability.

[Save stability test]

The initial viscosity of the one-liquid epoxy resin composition obtained in the examples was measured at 20 rpm and 25 ° C by an E-type viscometer according to JIS K-6870. Moreover, these were stored in a thermostatic chamber at 25° C., and after 4 days, the viscosity was measured at 20 rpm and 25° C. using an E-type viscometer, and the storage stability was evaluated in comparison with the initial viscosity. [Viscosity after 4 days]/[Initial viscosity] If it is less than 1.2, it is evaluated as ○; if it is less than 1.2, it is evaluated as △; if it is 2.0 or more, it is evaluated as ×.

[Adhesive strength]

According to JIS K-6850, an adhesive portion having a size of 100 mm × 25 mm was produced between two pieces of ground iron (thickness 1.6 mm), and the one-liquid epoxy resin composition obtained in the examples was applied thereto and given 120. The heat of °C, for 60 minutes, hardened the resin composition and adhered two pieces of ground iron. The thickness of the cured resin was 3 mm. The above resin was hardened by setting a tensile speed of 25 ° C and 1 mm/min by a TENSILON universal testing machine (TENSILON UTM-ST manufactured by Toyo Seiki Co., Ltd.). Tensile shear of the object.

[Peeling test]

According to JIS K-6854, an adhesive portion having a size of 150 mm × 300 mm was prepared between two pieces of ground iron (thickness: 1.6 mm), and the one-liquid epoxy resin composition obtained in the examples was applied thereto and given 120. The heat of °C, for 60 minutes, hardened the resin composition and adhered two pieces of ground iron. The cured resin had a thickness of 3 mm. This was subjected to a peeling test by setting a tensile speed of 25 ° C and 50 mm/min by a TENSILON universal testing machine (RTM-500 manufactured by ORIENTEC Co., Ltd.).

The resin compositions of Examples 1 to 4 were confirmed to be hardened within 5 minutes at 80 ° C and 100 ° C; the resin composition of Example 5 The material was confirmed to be hardened within 5 minutes at 100 ° C, and it was revealed that the thiol compound of the present invention is useful as a curing agent for an epoxy resin. It was found that the adhesion strength and the peeling test result were also good, and it was a resin composition which can be fully used.

In the epoxy equivalent of the epoxy resin of the component (2), the total equivalent amount of the thiol groups (the total number of thiol groups/epoxide equivalents) contained in the component (1) is 1.0.

As long as the mass of the component (1) [component (1) / (component (1) + component (5))]] is 0.1 to 1.0, as long as it is the total mass of the component (1) and the component (5), It is known that it is a one-liquid epoxy resin composition which has both good storage stability and quick-curing property.

The hardener of the present invention can have a storage stability of 4 days or more even at 25 ° C, and exhibits low-temperature quick-curing property.

[Industry Utilization]

A novel hardener for epoxy resins can be provided by the present invention. By combining the curing agent for a resin of the present invention with the component (2) and optionally with the component (3), the component (4) and/or (5) to form a resin composition, it is possible to exhibit a low temperature speed. A single-liquid epoxy resin composition which is excellent in hardenability and storage stability.

It is suitable for applications such as adhesives, injection molding agents, sealants, sealants, fiber-reinforced resins, coating agents, and coatings in all fields including the field of low-temperature-speed hardening.

Claims (15)

a compound containing a thiol group, which is represented by the formula (1), (In the formula (1), R represents a hydrogen atom, a hydrocarbon group which may have a substituent, or -CH ₂ -OC(O)-[CH ₂ ] _l -SH (1 is an integer of 1 to 8); X and The Z series independently represents a divalent aliphatic hydrocarbon group which may have a substituent; the Y system represents a selected from -OC(O)-, -C(O)O-, -NHC(O)-, -C(O)NH- , -C(O)- and -C(O)S-, a divalent group; m is an integer from 1 to 8; n is an integer from 1 to 8). The thiol group-containing compound of claim 1, wherein R represents a hydrogen atom or a saturated or unsaturated linear or branched hydrocarbon group having 1 to 15 carbon atoms, and the X and Z systems independently represent a substitutable group. A divalent alkyl group having 1 to 20 carbon atoms. A thiol group-containing compound according to claim 1 or 2 which is 2-ethyl-2-{{{3-[(3-indolylpropyl)thio]propanyl}oxy}methyl}propane -1,3-diylbis(3-mercaptopropionate). A hardener for an epoxy resin, which comprises the thiol group-containing compound according to any one of claims 1 to 3. A one-component epoxy resin composition containing the thiol group-containing compound (component (1)) according to any one of claims 1 to 3, and an epoxy having two or more epoxy groups in the molecule Resin (ingredient (2)). The one-component epoxy resin composition according to claim 5, which further contains a solid dispersion type latent curing accelerator (ingredient (3)). When the content of the component (2) is 100 parts by mass, the content of the component (3) is 0.1 to 100 parts by mass. The one-component epoxy resin composition according to any one of claims 5 to 7, which further comprises a boronic acid ester compound, a titanate compound, an aluminate compound, a zirconate compound, an isocyanate compound, and a carboxyl group. One or more of an acid, an acid anhydride, and a mercapto organic acid (ingredient (4)). When the content of the component (2) is 100 parts by mass, the content of the component (4) is 0.001 to 50 parts by mass. The one-component epoxy resin composition according to any one of claims 5 to 7, further comprising a compound (component (5)) having two or more thiol groups in the molecule different from the component (1). The one-component epoxy resin composition of claim 10, wherein the component (5) is trimethylolpropane ginseng (3-mercaptopropionate). The single-liquid epoxy resin composition of claim 10, wherein the mass of the component (1) is relative to the total mass of the component (1) and the component (5) The amount [ingredient (1) / (component (1) + component (5)))] is 0.001 to 1.0. The one-component epoxy resin composition according to any one of claims 5 to 7, wherein the epoxy equivalent of the epoxy resin of the component (2) and the total equivalent of the thiol group contained in the component (1) [The total number of thiol groups/number of epoxy equivalents] is 0.2 to 2.0. The single-liquid epoxy resin composition of claim 10, wherein the epoxy equivalent of the epoxy resin of the component (2), the total equivalent of the thiol groups contained in the component (1) and the component (5) [ The total number of thiol groups/number of epoxy equivalents is 0.2 to 2.0. An epoxy resin cured product obtained by heating the one-component epoxy resin composition according to any one of claims 5 to 14.