JP4372532B2 - Epoxy resin composition - Google Patents

Description

  The present invention relates to an epoxy resin composition. Specifically, the epoxy resin composition contains a specific aliphatic diglycidyl compound, has excellent curability, and has excellent coating film properties and chemical resistance, and molding. The present invention relates to an epoxy resin composition having excellent properties and releasability.

  Epoxy resins are widely used as paints, adhesives, molded products and the like because they are excellent in adhesion to various substrates, heat resistance, chemical resistance, electrical properties, mechanical properties, and the like.

  Among epoxy resins, aromatic group-containing epoxy resins such as bisphenol A type epoxy resins and phenol novolac type epoxy resins are excellent in curability, adhesion to substrates, heat resistance, chemical resistance, etc., and inexpensive. For this reason, it is widely used in all fields.

  However, these aromatic group-containing epoxy resins have a disadvantage that workability is inferior because of their high viscosity at room temperature. In order to solve this problem, workability is improved by using a diluent.

Diluents include non-reactive diluents and reactive diluents.
As the non-reactive diluent, a solvent, a plasticizer and the like are usually used. As solvents, toluene, methyl ethyl ketone, etc. are widely used as excellent diluents, but these volatile organic solvents are increasingly being avoided due to their toxicity and impact on air pollution. . Further, unlike a volatile organic solvent, the plasticizer has little influence on the outside world, but it may remain in the cured product and adversely affect its physical properties.

  On the other hand, reactive diluents have reactive groups such as epoxy groups in the molecule, so release to the environment is suppressed, and further, they do not remain in a cured product in a free state, affecting the physical properties. Is also small. As reactive diluents, monoglycidyl ethers of alcohols such as butyl monoglycidyl ether and diglycidyl ethers of aliphatic glycols such as polypropylene diglycidyl ether are used. From the viewpoint of wearability, many monoglycidyl ethers having an aliphatic chain are used (for example, see Patent Documents 1 to 4).

  However, when a monoglycidyl-based diluent is used, the crosslink density of the cured product is lowered, which adversely affects various physical properties such as the surface hardness of the cured product, chemical resistance and water resistance.

  Moreover, when manufacturing a molded article, the mold release property of an epoxy resin and a metal mold | die becomes a problem. Therefore, various release agents have been used so far. Examples of the release agent include hydrocarbons such as paraffin and low molecular weight polyethylene, fatty acids such as stearic acid, fatty alcohols such as stearyl alcohol, fatty acid amides such as ethylenebisstearoamide, glycerin triester and the like. A partial ester type such as an ester type or a glycerin monoester, a metal soap type such as calcium stearate, magnesium stearate or lead stearate, a special ester type or a mixture thereof is used.

  However, particularly when these mold release agents are used as internal mold release agents, there is a problem that if an effective amount is used, the physical properties of the molded product are deteriorated and the appearance is deteriorated due to the bleeding out of the mold release agent. It was.

JP-A-5-32868 JP-A-6-172336 JP-A-7-97431 Japanese Patent Application Laid-Open No. 8-119955

  An object of the present invention is to provide an epoxy resin composition excellent in various physical properties and various resistances by providing a reactive diluent such as a polyfunctional glycidyl ether having an aliphatic chain in the side chain, and molding. An object of the present invention is to provide an epoxy resin composition excellent in releasability from a mold during processing.

  As a result of intensive studies, the present inventors have found that an epoxy resin composition containing a specific aliphatic diglycidyl compound, in particular, an epoxy resin composition using the aliphatic diglycidyl compound and an aromatic group-containing epoxy resin in combination. The present inventors have found that the above-described demand can be satisfied and have reached the present invention.

That is, the present invention provides an epoxy resin composition comprising a compound represented by the following general formula (I) and a curing agent .

  According to the present invention, there is provided an epoxy resin composition suitable for use in paints, adhesives, etc., which has a high curing speed and excellent cured material properties, or an epoxy resin composition which is excellent in releasability and suitable for use in molded products. can do.

  Hereinafter, the epoxy resin composition of the present invention will be described in detail.

In the general formula (I), examples of the alkyl group having 1 to 30 carbon atoms represented by R ₁ include methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, nonyl, decyl, undecyl, dodecyl, Examples include groups such as tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl, etc. It may have.
Further, in the general formula (I), n is a 0.2 to 5, preferably from 0.5 to 2, but X ₁ and X ₂ are at least 50 mol% combined are glycidyl groups, 60 mole % Or more is preferably a glycidyl group.

Among the compounds represented by the above general formula (I), a compound in which R ₁ is an alkyl group having an average carbon number of 8 to 14 can exert an effect as a reactive diluent of an epoxy resin. Is polyfunctionalized, the epoxy resin composition using this is excellent in various physical properties and various resistances, and is suitable for applications such as paints and adhesives. Moreover, since the compound whose R < ₁ > is a C15-C30 alkyl group can also show the effect as an internal mold release agent, the epoxy resin composition using this is suitable for the use of a molded article. It is.

  Although the manufacturing method of the polyepoxy compound represented with the said general formula (I) used for the epoxy resin composition of this invention is not specifically limited, For example, mono of glycerol (1-30 carbon atoms) ) It can be easily prepared by adding epichlorohydrin to an alkyl ether.

As the above-mentioned mono (carbon atom number 1 to 30) alkyl ether of glycerin, a commercially available one can be used as it is. For example, a diol is produced by adding glycidol to a monoalcohol having 1 to 30 carbon atoms. Further, it can also be produced by adding epichlorohydrin thereto. Moreover, it can manufacture also by hydrolyzing a C1-C30 alkyl glycidyl ether.
Examples of the method of adding glycidol to the above monoalcohol include a method of dissolving monoalcohol in a solvent and dropping glycidol in the presence of a Lewis acid catalyst. Examples of the Lewis acid catalyst include boron trifluoride or a complex thereof, stannic chloride, trifluoromethanesulfonic acid, a perchloric acid metal salt, and the like.
The amount of glycidol used in this reaction is preferably in the range of 0.2 to 10 mol, particularly 0.4 to 1.5 mol, per 1 epoxy equivalent of the epoxy compound.
This reaction can also be carried out in a solvent such as hydrocarbon, ether or ketone.
This reaction is preferably carried out in the range of 20 to 150 ° C, particularly 50 to 120 ° C. If it is less than 20 ° C., the reaction is delayed and a long reaction time is required.

The addition of epichlorohydrin to the above mono (carbon atom number 1 to 30) alkyl ether of glycerin can be easily performed by reacting in the presence of an alkali and an intercalation catalyst.
Examples of the alkali include sodium hydroxide, potassium hydroxide, and calcium hydroxide. Examples of the interlayer transfer catalyst include tetramethylammonium chloride, tetrabutylammonium bromide, methyltrioctylammonium chloride, methyltrimethyl. Decylammonium chloride, N, N-dimethylpyrrolidinium chloride, N-ethyl-N-methylpyrrolidinium iodide, N-butyl-N-methylpyrrolidinium bromide, N-benzyl-N-methylpyrrolidinium chloride N-ethyl-N-methylpyrrolidinium bromide, N-butyl-N-methylmorpholinium bromide, N-butyl-N-methylmorpholinium iodide, N-allyl-N-methylmorpholinium bromide, N-methyl-N-benzyl pipette Dinium chloride, N-methyl-N-benzylpiperidinium bromide, N, N-dimethylpiperidinium iodide, N-methyl-N-ethylpiperidinium acetate, N-methyl-N-ethylpiperidinium iodide Tetramethylammonium chloride is preferable.
The amount of epichlorohydrin used in this reaction is preferably in the range of 1 equivalent or more, particularly 2 to 10 equivalents, relative to 1 equivalent of the hydroxyl group of diglycidyl ether. The alkali is preferably used in an amount of 0.1 to 2.0 mol, particularly 0.3 to 1.5 mol, based on 1 equivalent of the hydroxyl group to be glycidylated, and the interlayer transfer catalyst is based on the total weight of the reactants. , 0.01 to 10% by weight, and particularly preferably 0.2 to 2% by weight.
This reaction can also be carried out in a solvent such as hydrocarbon, ether or ketone.
This reaction is preferably carried out in the range of 20 to 150 ° C, particularly 50 to 120 ° C. If it is less than 20 ° C., the reaction is delayed and a long reaction time is required.

  The compound represented by the general formula (I) can be combined with a curing agent or the like alone to form an epoxy resin composition, but when used in combination with a curing agent or the like together with an aromatic group-containing epoxy resin, its effect Can be further exhibited, which is preferable.

  Examples of the aromatic group-containing epoxy resin include mononuclear polyhydric phenol compounds such as hydroquinone, resorcin, pyrocatechol, and phloroglucinol, or polyglycidyl ether compounds such as ethylene oxide and / or propylene oxide adducts thereof; Naphthalene, biphenol, methylene bisphenol (bisphenol F), methylene bis (orthocresol), ethylidene bisphenol, isopropylidene bisphenol (bisphenol A), isopropylidene bis (orthocresol), tetrabromobisphenol A, 1,3-bis (4-hydroxy) Cumylbenzene), 1,4-bis (4-hydroxycumylbenzene), 1,1,3-tris (4-hydroxyphenyl) butane, 1,1,2,2-the Polynuclear polyhydric phenol compounds such as la (4-hydroxyphenyl) ethane, thiobisphenol, sulfobisphenol, oxybisphenol, phenol novolak, orthocresol novolak, ethylphenol novolak, butylphenol novolak, octylphenol novolak, resorcin novolak, terpene diphenol or the like Polyglycidyl ether compounds such as ethylene oxide and / or propylene oxide adducts; ethylene glycol, propylene glycol, butylene glycol, hexanediol, polyglycol, thiodiglycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, bisphenol A- Polyhydric alcohols such as ethylene oxide adducts, phthalic acid, Polyglycidyl ethers of polyester polyols with aromatic polycarboxylic acids such as merit acid and pyromellitic acid; the mononuclear or polynuclear phenol compounds and maleic acid, fumaric acid, itaconic acid, succinic acid, glutaric acid, suberic acid, adipic acid , Azelaic acid, sebacic acid, dimer acid, trimer acid, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, trimesic acid, pyromellitic acid, tetrahydrophthalic acid, hexahydrophthalic acid, endomethylenetetrahydrophthalic acid, etc. Polyglycidyl ether of polyester polyol is mentioned. These epoxy resins may be internally crosslinked by a prepolymer of a terminal isocyanate.

  Among these aromatic group-containing epoxy resins, the use of a bisphenol-type epoxy resin represented by the following general formula (II) is preferable because an epoxy resin composition having an excellent balance of heat resistance and strength can be obtained. .

  The bisphenol type epoxy resin in which part or all of X represented by the general formula (II) is a glycidyl group is a polyfunctional compound described in JP-A Nos. 2001-151857, 2002-88229, and the like. It is an epoxy resin, and its manufacturing method is described in these publications.

  When the compound represented by the general formula (I) and the aromatic group-containing epoxy resin are used in combination, the aromatic-containing epoxy resin is 50 to 99 parts by weight, preferably 70 to 97 parts by weight. And 50 to 1 part by weight, preferably 30 to 3 parts by weight of the compound represented by the general formula (I).

  In general, the epoxy resin composition of the present invention is used in combination with a curing agent.

  The curing agent can be used without particular limitation as long as it is usually used as a curing agent for epoxy resins. For example, organic polyamines such as aromatic, aliphatic, or heterocyclic polyamines. These polyepoxide addition-modified products, amidation-modified products, Mannich-modified products and the like can be used as necessary.

  Examples of the organic polyamines include polyalkylpolyamines such as diethylenetriamine, triethylenetriamine, and tetraethylenepentamine; 1,2-diaminocyclohexane, 1,4-diamino-3,6-diethylcyclohexane, isophoronediamine, and the like. Alicyclic polyamines; aromatic polyamines such as m-xylylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, and the like. In addition, the polyepoxy addition-modified product includes these organic polyamines, glycidyl ethers such as phenyl glycidyl ether, butyl glycidyl ether, bisphenol A-diglycidyl ether, bisphenol F-diglycidyl ether, or glycidyl esters of carboxylic acid. It can manufacture by making various epoxy resins, such as, react with a conventional method. The amidation-modified product can be produced by reacting these organic polyamines with carboxylic acids such as phthalic acid, isophthalic acid, and dimer acid by a conventional method. The above-mentioned Mannich modified product usually contains these organic polyamines and aldehydes such as formaldehyde and phenols having at least one aldehyde-reactive site in the nucleus such as phenol, cresol, xylenol, tert-butylphenol, and resorcin. It can be produced by reacting by a method.

  The amount of the curing agent used varies depending on the type, purpose, curing temperature, curing time, and the like, but may be an amount sufficient to react with the epoxy group in the resin composition. The amount is 1 to 100 parts by weight, preferably 5 to 50 parts by weight per part. When the amount of the curing agent used is less than 1 part by weight, curing is insufficient and adhesion and corrosion resistance are inferior. When it is more than 100 parts by weight, unreacted amine remains and solvent resistance decreases, and This is not preferable because the solvent dilutability may be reduced.

  In addition, a solvent can be added to the epoxy resin composition of the present invention for easy handling. Examples of the solvent include ketones such as methyl ethyl ketone, methyl amyl ketone, diethyl ketone, acetone, methyl isopropyl ketone, propylene glycol monomethyl ether acetate and cyclohexanone; tetrahydrofuran, 1,2-dimethoxyethane, 1,2-diethoxyethane. Ethers such as ethyl acetate and n-butyl acetate; alcohols such as iso- or n-butanol, iso- or n-propanol and amyl alcohol; aromatic hydrocarbons such as benzene, toluene and xylene; Terpene hydrocarbon oils such as turpentine oil, D-limonene, and pinene; paraffinic solvents such as mineral spirit, Swazol # 310 (Cosmo Matsuyama Oil Co., Ltd.), Solvesso # 100 (Exxon Chemical Co., Ltd.); carbon tetrachloride , Chlorophor , Trichlorethylene, halogenated aliphatic hydrocarbons such as methylene chloride, halogenated aromatic hydrocarbons such as chlorobenzene; aniline, triethylamine, pyridine, dioxane, acetic acid, acetonitrile, carbon disulfide, and the like.

  In addition, the epoxy resin composition of the present invention includes a curing catalyst; a reactive or non-reactive diluent (plasticizer) such as a curing catalyst; monoglycidyl ethers, dioctyl phthalate, dibutyl phthalate, benzyl alcohol, coal tar, etc. ); Fillers such as glass fiber, carbon fiber, cellulose, silica sand, cement, kaolin, clay, aluminum hydroxide, bentonite, talc, silica, fine powder silica, titanium dioxide, carbon black, graphite, iron oxide, bitumen Or pigments; thickeners; thixotropic agents; flame retardants; antifoaming agents; rust inhibitors; conventional additives such as colloidal silica and colloidal alumina may be contained, and adhesives such as xylene resins and petroleum resins Resin may be used in combination.

The epoxy resin composition of the present invention is, for example, a paint or adhesive for concrete, cement mortar, various metals, leather, glass, rubber, plastic, wood, cloth, paper, etc .; adhesive tape for packaging, adhesive label, frozen food label , Removable labels, POS labels, adhesive wallpaper, adhesives for adhesive flooring; processed paper such as art paper, lightweight coated paper, cast coated paper, coated paperboard, carbonless copying machine, impregnated paper; natural fiber, synthetic fiber, It can be used for a wide range of applications such as fiber processing agents such as glass fibers, carbon fibers and metal fibers, fraying prevention agents and processing agents; and building materials such as sealing materials, cement admixtures and waterproofing materials.
Among these, when R ₁ in the general formula (I) is an alkyl group having an average carbon number of 8 to 14, it is suitable for use as a paint or an adhesive, and R in the general formula (I). _{When 1} is an alkyl group having an average carbon number of 15 to 30, it is suitable for use as a molded product.

  Hereinafter, the epoxy resin composition of the present invention will be described in more detail with reference to production examples and examples, but the present invention is not limited thereto.

[Production Example 1]
A four-necked flask equipped with a cooling tube, a stirring device, a dropping device, a thermometer, and a nitrogen gas introducing device was charged with 172 parts by weight of NIKKOL batyl alcohol EX (manufactured by Nikko Chemicals; glycerin monostearyl ether) at 75 ° C. Until dissolved. As a catalyst, 6.0 parts by weight of anhydrous tin (IV) chloride (manufactured by Kanto Chemical Co., Inc .; SnCl ₄ (IV) anhydride) was added, and 100 parts by weight of epichlorohydrin was added dropwise over 1 hour, and 1.5 The hydration reaction was performed after aging. After confirming the disappearance of the oxolane ring in the system by the absorption amount of hydrochloric acid, 83 parts by weight of 48% by weight aqueous caustic soda solution was added dropwise at a reaction temperature of 60 to 70 ° C. over 1 hour to carry out a ring-closing reaction. After completion of dropping, the mixture was further aged for 2 hours. The obtained reaction mixture was washed with toluene and water, and the solvent of the separated oil layer was removed to obtain 230.0 g (yield 97%) of a light yellow transparent liquid epoxy compound 1. The resulting epoxy compound 1 had an epoxy equivalent of 250 and was a white wax. The obtained epoxy compounds 1, as determined by GPC, in n = 1, 88.9 mole% combined of X ₁ and X ₂ were glycidyl group.

[Production Example 2]
In a four-necked flask equipped with a condenser, a stirring device, a dropping device, a thermometer, and a nitrogen gas introducing device, 195 parts by weight of Dovanol D23 (Mitsubishi Chemical Corporation; C12-13 alkyl alcohol) and 12 parts by weight of toluene were added. Charged and stirred and heated. 8 parts by weight of anhydrous tin (IV) chloride (manufactured by Kanto Chemical Co., Inc .; SnCl ₄ (IV) anhydride) was added as a catalyst, and 37 parts by weight of epiol OH (manufactured by NOF Corporation; glycidol) was added to the reaction temperature. The addition reaction was performed dropwise at 60 to 75 ° C. over 1.5 hours. Further, aging was performed at 60 to 70 ° C. for 1 hour, and it was confirmed by absorption of hydrochloric acid that the oxolane ring in the system had disappeared. Next, 166.5 parts by weight of epichlorohydrin was added dropwise over 1 hour, and the mixture was aged for 1.5 hours to carry out a hydration reaction. After confirming the disappearance of the oxolane ring in the system by the absorption amount of hydrochloric acid, 132 parts by weight of 48% by weight sodium hydroxide was added dropwise at a reaction temperature of 60 to 70 ° C. over 1 hour to carry out a ring closing reaction. After completion of dropping, the mixture was further aged for 2 hours. The obtained reaction mixture was washed with toluene and water, and the solvent of the separated oil layer was removed to obtain a light yellow transparent liquid epoxy compound 2. The obtained epoxy compound 2 had an epoxy equivalent of 307 and a viscosity of 20 cP (25 ° C.). The obtained epoxy compound 2, determined by GPC, with n = 0.5, 61.6 mole% combined of X ₁ and X ₂ were glycidyl group.

[Example 1]
Using bisphenol A type epoxy resin, epoxy compound 1 obtained in Production Example 1 above, methyltetrahydrophthalic anhydride (Me-THPA) and 2,4,6-tris (dimethylaminomethyl) phenol (TDMPAMP), Table 1 The curable epoxy resin compositions of Examples 1-1 to 1-2 were prepared according to the formulation shown in FIG.
The obtained curable epoxy resin composition was cured using a casting container having a thickness of 3 mm at 80 ° C. for 3 hours and further at 120 ° C. for 5 hours, and the Shore D hardness at 25 ° C. of the cured product was measured. .
In addition, a test piece was prepared from a cured product cured at 80 ° C. for 3 hours and further at 120 ° C. for 5 hours, and a tensile test (tensile speed 5 mm / min) was performed in accordance with JIS K 7113, and tensile stress MPa) and elongation (%).
Further, the cured product cured at 80 ° C. for 3 hours and further at 120 ° C. for 5 hours was immersed in water, 10% by weight hydrochloric acid and 10% by weight caustic soda for 7 days, respectively, and then the volume enlargement ratio of the cured product ( %) (Water resistance, hydrochloric acid resistance, alkali resistance).
Also, the curable epoxy resin composition was cured using a 20φ × 0.5 cm cylindrical mold at 80 ° C. for 1 hour and further at 120 ° C. for 3 hours, and extruded using a 500 N push-pull gauge. Evaluation of releasability was performed. This operation was performed 6 times, and the number of times of releasing was defined as releasing property (0/6: not released at all to 6/6: all released).
These results are shown in Table 1.

[Comparative Example 1]
The curable epoxy resin compositions of Comparative Examples 1-1 to 1-4 were prepared according to the formulation shown in Table 1, and in the same manner as in Example 1, Shore D hardness measurement, tensile test, volume enlargement ratio measurement, and mold release Sex evaluation was performed. These results are shown in Table 1. In addition, the comparative compounds 1 and 2 in Table 1 are as follows.
Comparative compound 1: Stearyl alcohol monoglycidyl ether, epoxy equivalent 330
Comparative compound 2: carnauba wax

[Example 2]
Using bisphenol A type epoxy resin as the main agent and epoxy compound 2 obtained in Production Example 2 above, and ADEKA HARDNER EH-220 (manufactured by Asahi Denka Kogyo Co., Ltd .; fatty acid-modified amine curing agent) as the curing agent, Table 2 A curable epoxy resin composition of Example 2-1 was prepared according to the formulation shown in FIG. The curable epoxy resin composition was cured at room temperature for 7 days to prepare a cured product.
The Shore D hardness at 25 ° C. of the cured product was measured.
A predetermined test piece was prepared from the cured product, and a tensile test was performed according to JIS K 7113 to determine tensile stress (MPa) and elongation (%).
Furthermore, the volume enlargement ratio (%) after immersing the cured product in boiling water for 2 hours, in 10% by weight hydrochloric acid for 7 days and in 10% by weight caustic soda for 7 days was determined (boiling water resistance, hydrochloric acid resistance, alkali resistance). ).
Moreover, a predetermined test piece was created from the cured product, and a compression test (compression speed 5 mm / min) was performed according to JIS K 7181 to determine a compression stress (MPa).
In addition, a shear adhesion test (tensile speed: 5 mm / min) was performed according to JIS K 6850, and a shear adhesion force (MPa) was obtained. A single-side polished steel plate (adhesive surface is a polished surface) was used as the base material, and the test was carried out after standing at room temperature for 7 days after bonding.
Moreover, about the said curable epoxy resin composition, the gelatinization time at room temperature by the main ingredient 50g scale was measured.
Further, the viscosity of the main agent was measured at 25 ° C.
These results are shown in Table 1.

[Comparative Example 2]
The curable epoxy resin compositions of Comparative Examples 2-1 to 2-3 were prepared according to the formulation shown in Table 2, and each physical property was measured in the same manner as in Example 2. These results are shown in Table 2. In addition, the comparative compounds 3 and 4 in Table 2 are as follows.
Comparative compound 3: dovanol monoglycidyl ether, epoxy equivalent 320
Comparative compound 4: Polypropylene diglycidyl ether, epoxy equivalent 310

  As is clear from Table 1, the general-purpose bisphenol A type epoxy resin is extremely inferior in the releasability (Comparative Example 1-1). If a general-purpose release agent such as monoglycidyl ether of a long-chain alcohol or wax is used in combination with this, the release property is improved, but it is necessary to add a large amount to fully demonstrate the effect. As a result, the physical properties decrease (Comparative Examples 1-2 to 1-4). On the other hand, by using the epoxy compound represented by the general formula (I) in combination, it is possible to improve the releasability without deteriorating the physical properties (Examples 1-1 to 1- 2).

  Further, as is apparent from Table 2, the general-purpose bisphenol A type epoxy resin has a high viscosity (Comparative Example 2-3). When a normal aliphatic diglycidyl ether such as polypropylene diglycidyl ether is used in combination with this, the effect of reducing the viscosity is small and the gelation time is also long (Comparative Example 2-2). Further, when the aliphatic monoglycidyl ether is used in combination, the effect of reducing the viscosity is great, but the gelation time is lengthened and the physical properties are significantly reduced (Comparative Example 2-1). On the other hand, when the epoxy compound represented by the general formula (I) is used in combination, the effect of reducing the viscosity is large, and the extension of the gelation time and the deterioration of the physical properties are suppressed.

Claims (7)

An epoxy resin composition comprising a compound represented by the following general formula (I) and a curing agent .

Further contains an aromatic group-containing epoxy resin, the total amount of 100 parts by weight of the compound represented by the aromatic group-containing epoxy resin and the above general formula (I), the content of the aromatic group-containing epoxy resin is 50 to The epoxy resin composition according to claim 1, wherein the content of the compound represented by the general formula (I) is 99 to 1 part by weight , and is 50 to 1 part by weight. The epoxy resin composition according to claim 2, wherein the aromatic group-containing epoxy resin is a bisphenol type epoxy resin represented by the following general formula (II).

In the general formula (I), the alkyl group der of R ₁ is an average 8 to 14 carbon atoms is, epoxy resin composition according to any one of claims 1 to 3 Rukoto wherein are used in coating applications . The epoxy resin composition according to any one of claims 1 to 3 , wherein, in the general formula (I), R ₁ is an alkyl group having an average carbon number of 8 to 14, and is used for an adhesive. object. The epoxy resin composition according to any one of claims 1 to 3, wherein in the general formula (I), R ₁ is an alkyl group having an average carbon number of 15 to 30.   The epoxy resin composition according to claim 6, wherein the epoxy resin composition is used for a molded product.