KR20120000103A - Epoxy resin, epoxy resin composition, and cured object - Google Patents

Abstract

Provided is an epoxy resin, an epoxy resin composition, and a cured product having low chlorine content, excellent heat resistance and mechanical strength, and are useful for paints, laminates, adhesives, and the like.
It is an epoxy resin obtained by making diepoxyethylbenzene and the compound which has two phenolic hydroxyl groups react, It depends on the epoxy resin represented by Formula (1), or the epoxy resin which has this as a main component. In Formula (1), A is a residue derived from the compound which has two phenolic hydroxyl groups. The present invention also relates to an epoxy resin composition containing the epoxy resin and a curing agent.

Description

Epoxy resin, epoxy resin composition and cured product {EPOXY RESIN, EPOXY RESIN COMPOSITION, AND CURED OBJECT}

The present invention relates to epoxy resins, epoxy resin compositions, and cured products useful for paints, laminates, adhesives, and the like.

Epoxy resins conventionally used in paints, laminates and adhesives have a low epoxy equivalent and poor adhesion and toughness of the cured product. So-called polymer epoxy resins polymerized with bromine bisphenol A or the like are generally used.

However, this polymer epoxy resin has excellent adhesiveness compared to liquid resin, but has the disadvantage of poor heat resistance and mechanical strength. As these improvement measures, Patent Document 1 uses an alkali metal compound and imidazole as a catalyst as a bifunctional epoxy resin and a bifunctional phenol, and uses a solvent having a boiling point of 130 ° C. or higher as a synthetic solvent to obtain a solid content concentration at the time of synthesis. By setting it as weight% or less, the method of making high molecular weight epoxy polymer with few branches, and improving strength is disclosed. Although there is no restriction | limiting in the bifunctional epoxy resin to be used, the illustrated epoxy resin is bisphenol-A epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, etc. It is a general thing, such as diglycidyl ether compound of functional phenols, the diglycidyl ether compound of bifunctional alcohol, these halides, hydrogenated substance, etc., and does not take the structure of an epoxy resin.

In addition, Patent Document 2 obtains by reacting a bifunctional epoxy resin (X) and a divalent phenol compound (Y) in the presence of a catalyst, and the requirements of the following (a) to (d):

(a) Mass average molecular weight is 30,000-200,000

(b) epoxy equivalent 5,000-20,000 g / equivalent

(c) Content of residual bifunctional epoxy resin (X) is 1000 ppm or less

(d) Content of residual dihydric phenolic compound (Y) is 100ppm or less

The high molecular weight epoxy resin composition comprising a high molecular weight epoxy resin and a curing agent reacting with the epoxy group has low elution, and has chemical resistance, solvent resistance, heat resistance, moldability, flexibility, impact resistance, It discloses to provide hardened | cured material excellent in adhesiveness and adhesiveness.

However, it is well known that reducing the remaining raw material improves the physical properties of the cured product. Although there is no restriction on the bifunctional epoxy resin to be used, the illustrated epoxy resins are bisphenol-type epoxy resins such as bisphenol-A epoxy resin, bisphenol-F epoxy resin, bisphenol-S epoxy resin and tetrabromobisphenol-A epoxy resin. Epoxy resin, 4,4'-biphenol, 3,3 ', 5,5'-tetramethyl-4,4'-biphenol and a biphenol type epoxy resin obtained by condensation reaction of epihalohydrin, cate Diglycidyl ether of monocyclic dihydric phenol, diglycidyl ether of dihydroxy naphthalene, epoxy resin which hydrogenated the aromatic ring of the said aromatic epoxy resin, diol of dihydric alcohol, such as chol, resorcinol, hydroquinone, etc. It is common to diglycidyl ester of dihydric carboxylic acid such as glycidyl ether, alicyclic epoxy resin, phthalic acid, isophthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, etc. It is not.

In addition, since the epoxy resin illustrated by patent documents 1 and 2 uses epichlorohydrin as a raw material, it contains chlorine of several tens to thousands ppm. Epoxy resins with low chlorine concentrations are desired in electrical and electronic component applications, and high-temperature epoxy resins with low chlorine content are expected.

Japanese Patent Laid-Open No. 11-147930 Japanese Laid-Open Patent Publication 2006-36801

Accordingly, an object of the present invention is to provide an epoxy resin, an epoxy resin composition, and a cured product having low chlorine content, excellent heat resistance and mechanical strength, and are useful for paints, laminates, adhesives, and the like.

In light of the above-described conventional state of the art, the present inventors have made diepoxyethylbenzene and phenolic properties as epoxy resins as a result of diligent research to obtain epoxy resins having low chlorine content, excellent heat resistance, and useful for paints, laminates and adhesives. By using the epoxy resin obtained by making the compound which has two hydroxyl groups react, it discovered that the said subject was solved and came to complete this invention.

The present invention relates to an epoxy resin represented by the following general formula (1).

Here, A represents the bivalent aromatic group which may have a substituent, n shows the number of 1-15.

In addition, the present invention is an epoxy resin obtained by reacting a diepoxyethylbenzene with a compound having two phenolic hydroxyl groups, and containing the epoxy resin represented by the general formula (1) as a main component. This epoxy resin can contain a subcomponent, and it is preferable to contain the epoxy resin represented by following General formula (2) as a subcomponent.

Here, A and n are synonymous with General formula (1). B ₁ is a divalent group represented by the following formula (3) or (4), B ₂ is a divalent group represented by the following formula (5) or the following formula (6), and B ₁ is a formula (3 Except for the divalent group represented by), B ₂ is a divalent group represented by (5).

The present invention also relates to a method for producing an epoxy resin, characterized by reacting a diepoxyethylbenzene with a compound having two phenolic hydroxyl groups. The epoxy resin obtained by this manufacturing method is an epoxy resin containing the epoxy resin represented by the said General formula (1) as a main component, and it is preferable to include the epoxy resin represented by the said General formula (2) as a subcomponent.

In the manufacturing method of the said epoxy resin, a bisphenol type compound or a biphenol type compound is mentioned preferably as a compound which has two phenolic hydroxyl groups.

The present invention also relates to an epoxy resin composition comprising the above epoxy resin and a curing agent. It is preferable that this epoxy resin composition also contains a hardening accelerator. Moreover, this invention relates to the epoxy resin hardened | cured material formed by shape-hardening this epoxy resin composition.

ADVANTAGE OF THE INVENTION According to this invention, the epoxy resin, epoxy resin composition, and hardened | cured material which are low in chlorine content, are excellent in heat resistance and mechanical strength, and are useful for a coating material, a laminated board, an adhesive agent, etc. can be provided.

1 shows the 1 H-NMR spectrum of the epoxy resin (A) of the present invention.

First, the epoxy resin of this invention is demonstrated.

The epoxy resin of this invention is represented by the said General formula (1). Here, since A is a divalent aromatic group which may have a substituent and is formed from a compound having two phenolic hydroxyl groups (hereinafter also referred to as a divalent phenol compound), it is also understood from the divalent phenol compound described below.

As these preferable bivalent aromatic groups, a phenylene group, a naphthylene group, an anthracene group, a diphenylmethane group, a 1, 1- diphenyl ethane group, a 1, 1, 1- methyl diphenyl ethane group, a diphenyl ether group, diphenyl Sulfide group, diphenyl sulfoxide group, diphenyl sulfone group, diphenyl ketone group, phenyl benzoate group, biphenyl group, stilbene group, diazobenzene group, aniline benzylidene group, derivatives thereof and the like. Here, the anthracene group refers to a group formed by removing two hydrogens from anthracene, and refers to a diphenylmethane group, a 1,1-diphenylethane group, a 1,1,1-methyldiphenylethane group, a diphenylether group, and a diphenylsulfur. Feed group, diphenyl sulfoxide group, diphenyl sulfone group, diphenyl ketone group, phenyl benzoate group, biphenyl group, stilbene group, diazobenzene group, aniline benzylidene group refers to the group represented by -Ph-X-Ph- , Ph is a benzene ring, X is CH ₂ , C ₂ H ₄ , C ₃ H ₆ , O, S, SO, SO ₂ , CO, COO, single bond, C ₂ H ₂ , N ₂ or CHN.

The divalent aromatic group may have a substituent, and preferred substituents include alkoxy groups such as hydrocarbon groups such as methyl group, ethyl group, allyl group, propargyl group, phenyl group and benzyl group, methoxy group, ethoxy group, allyloxy group and phenoxy group. And halogen groups such as fluorine, chlorine and bromine. Preferably they are a C1-C6 alkyl group, a C1-C6 alkoxy group, a C6-C8 aromatic hydrocarbon group, or halogen, such as chlorine and a bromine.

Especially, as a divalent aromatic group, it is preferable to have a structure excellent in symmetry with few steric hindrances from a viewpoint of high heat resistance, low thermal expansion, and low hygroscopicity, and especially a 2, 6- naphthylene group and a 1, 5- nap Tylene group, 4,4'- diphenylmethane group, 4,4'- diphenyl ether group, or 4,4'-biphenyl group is suitably selected.

In General formula (1), n represents the number of 1 to 15, and a preferable value of n changes with the use to apply. This number is an average value (number average). For example, it is preferable that it is low viscosity for the use of the semiconductor sealing material which requires high filling rate of a filler, The value of n is 1-5, Preferably it is 1-3, More preferably, it is 30 wt% that n is 1. That is to be included.

The epoxy resin of this invention can be manufactured by making diepoxy ethylbenzene and the bivalent phenol compound which has two phenolic hydroxyl groups react. In this reaction, an epoxy group of diepoxyethylbenzene is ring-opened to form a divalent phenol compound and an ether bond to bond and polymerize. The ring-opening can occur from either the α-position or the β-position, but the epoxy resin of formula (1) is the main component, and the epoxy resin of the general formula (2) is the minor component. When n is increased, an epoxy resin containing both of the structural units ring-opened at the α position and the β position is also included as a minor component. The structural unit ring-opened at the α position or the β position is represented by the formulas (3) to (6). Here, when the B ₁ and B ₂ of formula (2) at the same time have a structural unit of formula (3) and equation (5) becomes equal to the formula (1), the case is excluded.

The epoxy resin of this invention is an epoxy resin of Formula (1) or an epoxy resin which has this epoxy resin as a main component. In the case of the epoxy resin which has the epoxy resin of Formula (1) as a main component, the epoxy resin of Formula (2) is contained as a subcomponent. Moreover, the epoxy resin (henceforth also called epoxy resin 3) containing the structural unit ring-opened at the (alpha) position and the (beta) position as needed is contained. In the case of the epoxy resin containing the epoxy resin of the formula (1) as a main component, the epoxy resin of the formula (1) is usually 50% or more, preferably 60% or more. The epoxy resin of Formula (2) is less than 50%, Preferably it contains 10 to 40%. In addition, although the quantity of the epoxy resin 3 changes with n numbers, since the probability of ring opening in the alpha position and the beta position is the said range, it can be calculated from it substantially. But at most it is less than 50%. Further, the epoxy resin of formula (1), the epoxy resin of formula (2), and the epoxy resin (3) all have the same compositional formula and have similar epoxy groups and hydroxy.

The epoxy resin of this invention is obtained by reacting diepoxyethylbenzene and a bivalent phenolic compound at 50-200 degreeC for 1 to 20 hours in presence of a catalyst as needed.

The reaction ratio of diepoxyethylbenzene and the divalent phenolic compound is preferably a reaction ratio of 100/10 to 100/95, preferably 100/15 to 100/70 in the molar ratio of diepoxyethylbenzene and the divalent phenolic compound. Do. By adjusting this molar ratio, the number of n can be controlled. Moreover, the terminal can be made into an epoxy group by using diepoxyethylbenzene excessively.

As the catalyst which can be used at this time, for example, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, tertiary amines such as triethylamine and benzyldimethylamine, quaternary ammonium salts such as tetramethylammonium chloride, and imidazole compounds And phosphonium salts such as phosphine such as triphenylphosphine and tetra-n-butylphosphonium tetraphenylborate. Although the amount of the catalyst used varies depending on the catalyst to be used, the amount of the catalyst is preferably 0.001 to 3%, more preferably 0.01% to 2% based on the weight of diepoxyethylbenzene.

When performing reaction, you may use an organic solvent as needed. As an organic solvent, aromatic hydrocarbon solvents, such as toluene and xylene, ketone solvents, such as MIBK and MEK, etc. are mentioned, for example. As a usage-amount of a solvent, it is 10-1000 weight part normally with respect to 100 weight part of total weights of diepoxy ethylbenzene and a bivalent phenolic compound, Preferably it is 20-200 weight part.

Diepoxy ethylbenzene can use what epoxidized divinylbenzene with peroxide. Since epichlorohydrin is not used, the compound obtained has little chlorine content. As the peroxide, peracid, hydrogen peroxide, or organic peroxide obtained by a conventional method can be used. When divinylbenzene is an isomer mixture, this epoxy compound also becomes an isomer mixture, but it does not interfere.

As the divalent phenolic compound used in the production method of the present invention, any known one can be used, and a divalent phenolic compound represented by A (OH) ₂ having a phenolic hydroxyl group bonded to A can be used. Preferably, it is a bisphenol type compound or a biphenol type compound.

The epoxy resin obtained by the manufacturing method of this invention is an epoxy resin which has the epoxy resin of Formula (1) or this epoxy resin and the epoxy resin of Formula (2) as a main component. And a small amount of the epoxy resin (3).

As the curing agent used in the epoxy resin composition of the present invention, all known and conventional compounds can be used. Among them, latent curing agents such as dicyandiamide, imidazole, BF ₃ -amine complex, guanidine derivative, phenol, Various novolac resins and their modified products derived from substituted phenols and bisphenols, aromatic amines such as metaphenylenediamine, diaminodiphenylmethane and diaminodiphenylsulfone, polyamide resins and modified products thereof, and maleic anhydride And acid anhydride curing agents such as phthalic anhydride, hexahydrophthalic anhydride and pyromellitic anhydride. These curing agents may be used alone or in combination of two or more. It is preferable to use a hardening | curing agent separately for what is for normal temperature hardening, and for heat-hardening according to a use.

Although the usage-amount of these hardening | curing agents is not specifically limited, It is 2-70 weight part with respect to 100 weight part of solid content of an epoxy resin. However, since this mixing ratio changes greatly with the kind of hardening | curing agent to be used, it is necessary to determine optimal conditions suitably.

When using each said compound as a hardening | curing agent, a hardening accelerator can be used suitably. As a hardening accelerator, all well-known and conventional things can be used, For example, tertiary amine, imidazole, an organic acid metal salt, Lewis acid, an amine complex salt, etc. are mentioned, These are not only single, but also 2 or more types of combined use. It is possible.

Other components, such as a filler, a fiber, a coupling agent, a flame retardant, a mold release agent, a foaming agent, can be added to the epoxy resin composition of this invention as needed. As the filler at this time, for example, polyethylene powder, polypropylene powder, quartz, silica, silicate, calcium carbonate, magnesium carbonate, gypsum, bentonite, fluorspar, titanium dioxide, carbon black, graphite, iron oxide, aluminum powder, Examples of the fiber include iron, talc, mica, kaolin clay, and the like, such as cellulose fiber, glass fiber, carbon fiber, aramid fiber, and the like. As the coupling agent, for example, a silane coupling agent, a titanium coupling agent, and the like, are examples of the flame retardant. For example, bisphenol A, antimony trioxide, a phosphorus compound, etc., as a mold release agent, for example, stearic acid salt, silicone, wax, etc., As a blowing agent, Freon, dichloroethane, butane, pentane, dinitropentamethylenetetramine, para Toluenesulfonylhydrazide, or freon, dichloroethane, butane, pentane, etc. may be used for vinyl chloride-vinylidene chloride copolymer or styrene- (meth) acrylic acid. Expandable thermoplastic resin particles etc. which are filled in the shell of an ester copolymer are mentioned.

The epoxy resin composition of this invention can be easily made into the hardened | cured material of an epoxy resin composition by the method similar to the method known conventionally. For example, the epoxy resin and the curing agent of the present invention, if necessary, a curing accelerator and other additives, if necessary, by using an extruder, kneader, roll or the like until the mixture is sufficiently mixed to obtain an epoxy resin composition, the epoxy resin composition After melt | dissolution, it shape | molds using a mold or a transfer molding machine, etc., and can harden | cure a cured | cured material by heating at 80-200 degreeC.

In addition, the prepreg obtained by dissolving the epoxy resin composition of the present invention in a solvent, impregnating a substrate such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, paper, or the like by heating and drying, is cured by hot press molding. It can also be obtained. For example, the epoxy resin of the present invention, a curing agent, a dilution solvent, and the like are heated and stirred until uniform, impregnated in a glass cross, heated and semi-dried, and a prepreg containing a solvent powder is overlapped with the required number of sheets at 80 to 200 ° C. The glass cross laminated board can be produced by heat-pressing for 1 hour or more.

As a specific example of the dilution solvent which can be used at this time, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, methyl cellosolve, etc. are preferable, The usage-amount is 10 with respect to the total weight of an epoxy resin composition and the said dilution solvent. 70 weight%, Preferably it is 15-65 weight%.

Since the hardened | cured material obtained in this way has low chlorine content and high heat resistance, the epoxy resin composition of this invention can be used in a wide range of fields. Specifically, it can be used for a wide range of applications such as molding materials, casting materials, laminated materials, paints, adhesives, and resists.

<Examples>

Next, examples will be described in detail to clarify the features of the present invention. In addition, all "part" and "%" in a main body show a basis of weight.

Synthesis Example 1

300 parts of divinylbenzene (97% of DVB-960 divinylbenzene from Shin-Nitetsu Chemical Co., Ltd. content, m-body / p-body = 62: 38), and 1200 parts of ethyl acetate were charged and stirred in the 3 L reactor. Subsequently, 1640 parts of ethyl acetate solution containing 30% of peracetic acid were added dropwise for 3 hours. During dripping, it controlled so that reaction temperature might be 30 degreeC. After dripping was further performed at 30 ° C. for 3 hours. After cooling the reaction solution to room temperature, 1208 parts of 20% aqueous NaOH solution was added, and after stirring for 1 hour, the aqueous layer was separated and unreacted peracetic acid and acetic acid produced were removed. After distilling off ethyl acetate under reduced pressure with an evaporator, purified distillation (outflow temperature of 10 torr 150 ° C) was performed to obtain 151.6 parts of diepoxyethylbenzene. The epoxy equivalent of the obtained diepoxy ethylbenzene was 81 g / eq, the viscosity in 25 degreeC was 18 mPa * s, the purity was 97.1% (gas chromatography area%), m-form / p-form = 64:36 (1H-NMR) Integral ratio).

&Lt; Example 1 >

In a detachable flask equipped with a stirrer, a condenser and a thermometer, 61 parts of diepoxyethylbenzene prepared in Synthesis Example 1, 41 parts of bisphenol A (manufactured by Tokyo Kasei Kogyo Co., Ltd.) and methyl isobutyl ketone (Tokyo Kasei Kogyo Co., Ltd.) 102 parts of Co., Ltd. products were added, and the mixture was heated to 80 ° C and completely dissolved under stirring. Then, 0.07 part of triphenylphosphine was added as a catalyst, and the reaction was carried out for 6 hours by heating up to 130 ° C. After completion | finish of reaction, devolatilization was performed at 120 degreeC under reduced pressure of 5torr. 100 parts of epoxy resins (A) which are epoxy equivalent 259g / eq and a pale yellow transparent viscous liquid were obtained. The total chlorine content by the cylinder combustion method was less than 0.5 ppm. 1H-NMR spectrum of the epoxy resin (A) is shown in FIG. 1.

<Example 2>

Into a detachable flask equipped with a stirrer, a condenser and a thermometer, 61 parts of diepoxyethylbenzene prepared in Synthesis Example 1, 41 parts of bisphenol F (manufactured by Honshu Chemical Co., Ltd.) and 101 parts of methyl isobutyl ketone were added. The mixture was heated to 80 ° C and completely dissolved under stirring. Then, 0.07 part of triphenylphosphine was added as a catalyst, and the temperature was raised to 130 ° C to carry out the reaction for 6 hours. After completion | finish of reaction, devolatilization was performed at 120 degreeC under reduced pressure of 5torr. 100 parts of epoxy resins (B) which are an epoxy equivalent of 298 g / eq and a pale yellow transparent viscous liquid were obtained. The total chlorine content was less than 0.5 ppm.

<Example 3>

To a detachable flask equipped with a stirrer, a condenser and a thermometer, 61 parts of diepoxyethylbenzene prepared in Synthesis Example 1 and 4,4'-dihydroxybiphenyl ether (manufactured by Tokyo Kasei Kagaku Kogyo Co., Ltd.) 38 parts and 75 parts of methyl isobutyl ketones were added, and it heated at 80 degreeC, melt | dissolving completely under stirring, and added 0.07 part of triphenylphosphines as a catalyst, it heated up to 130 degreeC, and reacted for 6 hours. After completion | finish of reaction, devolatilization was performed at 120 degreeC under reduced pressure of 5torr. 82 parts of epoxy resins (C) which are an epoxy equivalent of 279 g / eq and a pale yellow transparent viscous liquid were obtained. The total chlorine content was less than 0.5 ppm.

<Example 4>

82 parts of 9,9-bis (4-hydroxyphenyl) fluorene (Tokyo Kasei Kagaku Kogyo Co., Ltd.) of diepoxyethylbenzene prepared in Synthesis Example 1 was added to a detachable flask equipped with a stirrer, a condenser and a thermometer. 88 parts of products and 80 parts of methyl isobutyl ketones were added, and it heated at 80 degreeC, melt | dissolving completely under stirring, 0.09 parts of triphenylphosphines were added as a catalyst, it heated up to 130 degreeC, and reaction was performed for 6 hours. After completion | finish of reaction, devolatilization was performed at 120 degreeC under reduced pressure of 5torr. 165 parts of epoxy resins (D) which are epoxy equivalent 342g / eq and light yellow solid were obtained. The total chlorine content was less than 0.5 ppm.

Epoxy resins (A) to (D) obtained in Examples 1 to 4 all have an epoxy resin represented by the general formula (1) as a main component, and the ratio thereof is about 70 wt%, which is represented by the general formula (2). The epoxy resin contained about 30 wt%.

<Examples 5-8>

To epoxy resins A to D obtained in Examples 1 to 4, lycaside MH-700 (4-methylhexahydro phthalic anhydride / hexahydro phthalic anhydride mixture (70/30) manufactured by Shin-Nihon Rika Co., Ltd.) has an equivalent ratio of 1.0. Mix so as to. 0.3% 2-ethyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd.) was added to the mixture and mixed uniformly, followed by heat curing at 120 ° C for 1 hour + 150 ° C for 3 hours. Got it.

Comparative Example 1

The bisphenol A type epoxy resin (YD-134 epoxy equivalent 246 g / eq total chlorine content 1700 ppm) and lycaside MH-700 were mixed so that an equivalent ratio might be 1.0. To the mixture, 0.3% 2-ethyl-4-methylimidazole was added and uniformly mixed, followed by heat curing at 120 ° C for 1 hour + 150 ° C for 3 hours to obtain a cured product.

Comparative Example 2

Bisphenol F type epoxy resin (YDF-170 epoxy equivalent 246 g / eq total chlorine content 1600 ppm) and lycaside MH-700 were mixed so that an equivalent ratio might be 1.0. To the mixture, 0.3% 2-ethyl-4-methylimidazole was added and uniformly mixed, followed by heat curing at 120 ° C for 1 hour + 150 ° C for 3 hours to obtain a cured product.

About the hardened | cured material obtained in Examples 5-8 and Comparative Examples 1-2, Tg (TMA method), bending elastic modulus, and bending strength were measured. Measurement conditions are as follows.

Tg: TMA method

Bending elastic modulus, bending strength; 3-point bend

The epoxy resin of the present invention has a lower chlorine content, excellent heat resistance and mechanical strength than epoxy resins generally used in the past, and can provide epoxy resins, epoxy resin compositions, and cured products useful for paints, laminates, adhesives, and the like. Can be.

Claims (9)

Epoxy resin, characterized by the following general formula (1).

Here, A represents the bivalent aromatic group which may have a substituent, n shows the number of 1-15. An epoxy resin obtained by reacting a diepoxyethylbenzene with a compound having two phenolic hydroxyl groups, and containing an epoxy resin represented by the following general formula (1) as a main component.

Here, A represents the bivalent aromatic group which may have a substituent, n shows the number of 1-15. The method of claim 2,
Epoxy resin characterized by including the epoxy resin represented by following General formula (2) as a subcomponent.

Here, A represents the bivalent aromatic group which may have a substituent, n shows the number of 1-15. B ₁ is a divalent group represented by the following formula (3) or (4), B ₂ is a divalent group represented by the following formula (5) or (6), and B ₁ is a formula (3 Except for the divalent group represented by), B ₂ is a divalent group represented by (5).

A method for producing an epoxy resin, wherein diepoxyethylbenzene and a compound having two phenolic hydroxyl groups are reacted. The method of claim 4, wherein
A method for producing an epoxy resin, wherein the compound having two phenolic hydroxyl groups is a bisphenol compound. The method of claim 4, wherein
A method for producing an epoxy resin, wherein the compound having two phenolic hydroxyl groups is a biphenol compound. An epoxy resin composition comprising the epoxy resin according to any one of claims 1 to 3 and a curing agent. The method of claim 7, wherein
Furthermore, the epoxy resin composition containing a hardening accelerator. A cured epoxy resin product obtained by molding and curing the epoxy resin composition according to claim 7.

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