JP2013028663A - Epoxy resin mixture, epoxy resin composition, prepreg, and cured material thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin exhibiting a high heat conductivity of a cured material thereof, and having a low viscosity and excellent workability.SOLUTION: The epoxy resin contains an epoxy resin (A) obtained by reacting a phenol compound (a) obtained by reacting a specific ketone compound with a specific aldehyde, with an epihalohydrin, and further contains an epoxy resin (B) and/or an epoxy resin (C) obtained by reacting at least one of two specific bisphenol compounds with a halohydrin.

Description

  The present invention relates to a novel epoxy resin mixture and an epoxy resin composition. Moreover, it is related with hardened | cured materials, such as a prepreg formed with this epoxy resin composition.

  Epoxy resin compositions are generally cured products with excellent mechanical properties, water resistance, chemical resistance, heat resistance, electrical properties, etc., such as adhesives, paints, laminates, molding materials, casting materials, etc. It is used in a wide range of fields. In recent years, cured products of epoxy resins used in these fields have begun to be highly purified and have various properties such as flame retardancy, heat resistance, moisture resistance, toughness, low linear expansion coefficient, and low dielectric constant characteristics. There is a need for improvement.

  In particular, in the electrical and electronic industry, which is a typical application of epoxy resin compositions, high-density mounting of semiconductors and high-density wiring of printed wiring boards have been promoted for the purpose of multi-function, high performance, and compactness. Although progress is being made, the heat generated from the inside of a semiconductor element or a printed wiring board increases with high-density mounting or high-density wiring, which may cause malfunction. Therefore, how to efficiently release generated heat to the outside is an important issue from the standpoint of energy efficiency and device design. These heat countermeasures include various measures such as using a metal core substrate, constructing a structure that easily dissipates heat at the design stage, and densely filling high thermal conductive filler in the polymer material (epoxy resin) to be used. Has been made. However, since the thermal conductivity of the polymer material acting as a binder that connects the high thermal conductivity sites is low, the thermal conduction speed of the polymer material becomes the rate-determining, and efficient heat dissipation is not possible at present.

  As a means for realizing high thermal conductivity of an epoxy resin, it is reported in Patent Document 1 that a mesogenic group is introduced into the structure. In the same document, as an epoxy resin having a mesogenic group, an epoxy resin having a biphenyl skeleton, etc. Is described. In addition, as an epoxy resin other than the biphenyl skeleton, a phenyl benzoate type epoxy resin is described. However, since the epoxy resin needs to be produced by an epoxidation reaction by oxidation, there are difficulties in safety and cost, and it is practical. It can not be said. Examples of using an epoxy resin having a biphenyl skeleton include Patent Documents 2 to 4, and among them, Patent Document 3 describes a technique in which an inorganic filler having high thermal conductivity is used in combination. However, the thermal conductivity of the cured product obtained by the methods described in these documents is not at a level that satisfies the market demand, and a cured product having higher thermal conductivity using an epoxy resin that is available at a relatively low cost. There is a need for an epoxy resin composition that provides.

  In addition, in order to obtain a cured product having high thermal conductivity, the characteristics required of an epoxy resin include, of course, high thermal conductivity when made into a cured product. Low viscosity is also an important property. In general, many high thermal conductive fillers are not spherical in shape as compared with general-purpose fillers, and are difficult to fill with high amounts. Therefore, the workability of the epoxy resin is improved as the viscosity is lower in the molten state. Therefore, in order to bring the viscosity of the epoxy resin to the level required by the market, it is strongly desired to reduce the viscosity.

Japanese Unexamined Patent Publication No. 11-323162 Japanese Unexamined Patent Publication No. 2004-2573 Japanese Unexamined Patent Publication No. 2006-63315 Japanese Unexamined Patent Publication No. 2003-137971

  The present invention has been made as a result of studies to solve such problems, and provides an epoxy resin mixture in which the cured product has high thermal conductivity, low viscosity, and excellent workability. .

As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.
That is, the present invention provides (1) the following formulas (1) to (5).

(In Formula (1), each R ₁ is independently present and is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a hydroxyl group, a nitro group, or an alkoxy having 1 to 10 carbon atoms. Represents one of the groups, l represents the number of R ₁ , and is an integer of 1 to 4)

(In Formula (2), each R ₂ is independently present, and is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkylcarbonyl group having 1 to 15 carbon atoms, or a carbon number. It represents any of 2-10 alkyl ester groups, C1-C10 alkoxy groups, morpholinylcarbonyl groups, phthalimide groups, piperonyl groups or hydroxyl groups.)

(In Formula (3), each R ₃ is independently present and is a hydrogen atom, an alkylcarbonyl group having 0 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or a carbon number. Represents an alkyl ester group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms or a hydroxyl group, n represents the number of carbon atoms, and represents an integer of 0, 1 or 2. m represents the number of R ₃ . And satisfies the relationship 1 ≦ m ≦ n + 2.)

(In the formula (4), _{R 4} are present each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, any of an alkoxy group or a hydroxyl group having 1 to 10 carbon atoms Represents.)

(In the formula (5), _{R 5} is present independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, 1 to 4 carbon atoms Represents an alkyl ester group of 10 to 10 or a hydroxyl group, and m is an integer of 1 to 10.)
One or more of the compounds represented by:
Following formula (6)

(In formula (6), each R ₆ is independently present and is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a hydroxyl group, a nitro group, a formyl group, an allyl group, or carbon. Represents one of the alkoxy groups of formula 1 to 10. k represents the number of R ₆ and is an integer of 1 to 4.) The phenol compound (a) and epihalohydrin obtained by the reaction with the compound represented by It contains an epoxy resin (A) obtained by reaction, and further has the following formula (7)

（式（７）中、Ｒ_７、ＸおよびＹは独立して存在し、水素原子、炭素数１〜１０のアルキル基もしくはアリール基、水酸基、又は炭素数１〜１０のアルコキシ基のいずれかを表す。ｋはＲ_７の数を表し、１〜４の整数を表す。）で表されるフェノール化合物（ｂ）にエピハロヒドリンを反応させて得られるエポキシ樹脂（Ｂ）および／または
式（８） Formula (7)

(In formula (7), R ₇ , X and Y are independently present, and represent any one of a hydrogen atom, an alkyl or aryl group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 10 carbon atoms. K represents the number of R ₇ and represents an integer of 1 to 4. The epoxy resin (B) and / or the formula (8) obtained by reacting an epihalohydrin with the phenol compound (b) represented by

（式（８）中、Ｒ_８、およびＡは独立して存在し、Ｒ_８は水素原子、炭素数１〜１０のアルキル基もしくはアリール基、水酸基、又は炭素数１〜１０のアルコキシ基のいずれかを表す。ｌはＲ_８の数を表し、１〜４の整数を表す。Ａは直接結合、もしくはシクロ環を有する炭素数５〜１５のアルキリデン基を表す。）で表されるフェノール化合物（ｃ）にエピハロヒドリンを反応させて得られるエポキシ樹脂（Ｃ）、
を含有するエポキシ樹脂混合物、
（２）
フェノール化合物（ａ）を含有し、さらにフェノール化合物（ｂ）および／またはフェノール化合物（ｃ）を含有するフェノール化合物混合物に、エピハロヒドリンを反応させて得られる（１）に記載のエポキシ樹脂混合物、
（３）
エピハロヒドリンと反応させる前の（１）に記載のフェノール化合物（ａ）〜（ｃ）の混合物のうち、フェノール化合物（ｂ）およびフェノール化合物（ｃ）の占める割合の和が１〜３０質量％であるフェノール化合物の混合物にエピハロヒドリンを反応させて得られる（２）に記載のエポキシ樹脂混合物、
（４）
（１）〜（３）のいずれか一項に記載のエポキシ樹脂混合物、硬化剤を含有してなるエポキシ樹脂組成物
（５）
（４）に記載のエポキシ樹脂組成物のうち、硬化剤としてフェノール化合物（ａ）を含有してなるエポキシ樹脂組成物
（６）
熱伝導率２０Ｗ／ｍ・Ｋ以上の無機充填材を含有してなる（４）または（５）のいずれか一項に記載のエポキシ樹脂組成物、
（７）
半導体封止用途に用いられる（４）〜（６）のいずれか一項に記載のエポキシ樹脂組成物、
（８）
（４）〜（６）のいずれか一項に記載のエポキシ樹脂組成物及びシート状の繊維基材からなるプリプレグ、
（９）
（４）〜（７）のいずれか一項に記載のエポキシ樹脂組成物、または前項（８）に記載のプリプレグを硬化してなる硬化物、
に関する。

(In Formula (8), R < ₈ > and A exist independently, R < ₈ > is any of a hydrogen atom, a C1-C10 alkyl group or aryl group, a hydroxyl group, or a C1-C10 alkoxy group. L represents the number of R ₈ and represents an integer of 1 to 4. A represents a direct bond or an alkylidene group having 5 to 15 carbon atoms having a cyclo ring.) an epoxy resin (C) obtained by reacting c) with an epihalohydrin,
An epoxy resin mixture containing,
(2)
The epoxy resin mixture according to (1) obtained by reacting an epihalohydrin with a phenol compound mixture containing the phenol compound (a) and further containing the phenol compound (b) and / or the phenol compound (c),
(3)
Of the mixture of the phenol compounds (a) to (c) described in (1) before the reaction with the epihalohydrin, the sum of the proportions of the phenol compound (b) and the phenol compound (c) is 1 to 30% by mass. The epoxy resin mixture according to (2) obtained by reacting a mixture of phenolic compounds with epihalohydrin,
(4)
The epoxy resin composition (5) comprising the epoxy resin mixture according to any one of (1) to (3) and a curing agent.
Among the epoxy resin compositions described in (4), an epoxy resin composition comprising a phenol compound (a) as a curing agent (6)
The epoxy resin composition according to any one of (4) and (5), comprising an inorganic filler having a thermal conductivity of 20 W / m · K or more,
(7)
The epoxy resin composition according to any one of (4) to (6), which is used for semiconductor sealing applications,
(8)
A prepreg comprising the epoxy resin composition according to any one of (4) to (6) and a sheet-like fiber base material,
(9)
(4)-the cured product formed by hardening | curing the epoxy resin composition as described in any one of (7), or the prepreg as described in previous clause (8),
About.

  The epoxy resin mixture of the present invention is excellent in workability due to its low melt viscosity, and further, its cured product is excellent in heat conduction. Therefore, various composite materials including semiconductor encapsulating materials and prepregs, adhesives, and paints This is useful when used for the above.

  The epoxy resin mixture of the present invention contains the following epoxy resin (A), and further comprises a mixture containing the following epoxy resin (B) and / or the following epoxy resin (C). First, the phenol compounds (a) to (c) which are precursors of the respective epoxy resins (A) to (C) will be described.

  The phenol compound (a) is obtained by a reaction between one or more compounds selected from the compounds represented by the following formulas (1) to (5) and a compound represented by the following formula (6).

(In the formula (1), _{R 1} is present independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a hydroxyl group, a nitro group, or 1 to 10 carbon atoms Represents one of alkoxy groups, and l represents the number of R ₁ and is an integer of 1 to 4.)

In Formula (1), R ₁ is independently present and is preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 10 carbon atoms, particularly a hydrogen atom or 1 carbon atom. ~ 3 alkoxy groups are preferred.

  Specific examples of the compound represented by the formula (1) used for the reaction with the compound represented by the formula (6) in order to obtain the phenol compound (a) include 2-hydroxyacetophenone, 3-hydroxyacetophenone, 4-hydroxyacetophenone, 2 ′, 4′-dihydroxyacetophenone, 2 ′, 5′-dihydroxyacetophenone, 3 ′, 4′-dihydroxyacetophenone, 3 ′, 5′-dihydroxyacetophenone, 2 ′, 3 ′, 4′- Trihydroxyacetophenone, 2 ′, 4 ′, 6′-trihydroxyacetophenone monohydrate, 4′-hydroxy-3′-methylacetophenone, 4′-hydroxy-2′-methylacetophenone, 2′-hydroxy-5 ′ -Methylacetophenone, 4'-hydroxy-3'-methoxyacetophenone, 2 ' Hydroxy-4'-methoxyacetophenone, 4'-hydroxy-3'-nitroacetophenone, 4'-hydroxy-3 ', 5'-dimethoxyacetophenone, 4', 6'-dimethoxy-2'-hydroxyacetophenone, 2'- Hydroxy-3 ′, 4′-dimethoxyacetophenone, 2′-hydroxy-4 ′, 5′-dimethoxyacetophenone, methyl 5-acetylsalicylate, 2 ′, 3′-dihydroxy-4′-methoxyacetophenone hydrate, and the like. It is done. Of these, 4'-hydroxy-3'-methoxyacetophenone, 4) -hydroxy-3'-methoxyacetophenone, because the solvent solubility when epoxidizing the resulting phenol compound is high and the cured product of the epoxy resin composition exhibits high thermal conductivity '-Hydroxyacetophenone is preferred.

(In Formula (2), each R ₂ is independently present, and is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkylcarbonyl group having 1 to 15 carbon atoms, or a carbon number. It represents any of 2-10 alkyl ester groups, C1-C10 alkoxy groups, morpholinylcarbonyl groups, phthalimide groups, piperonyl groups or hydroxyl groups.)

Specific examples of the compound represented by the formula (2) used for the reaction with the compound represented by the formula (6) in order to obtain the phenol compound (a) include acetone, 1,3-diphenyl-2- Propanone, 2-butanone, 1-phenyl-1,3-butanedione, 2-pentanone, 3-pentanone, 4-methyl-2-pentanone, acetylacetone, 2-hexanone, 3-hexanone, isoamyl methyl ketone, ethyl isobutyl ketone, 4-methyl-2-hexanone, 2,5-hexanedione, 1,6-diphenyl-1,6-hexanedione, 2-heptanone, 3-heptanone, 4-heptanone, 2-methyl-4-heptanone, 5- Methyl-3-heptanone, 6-methyl-2-heptanone, 2,6-dimethyl-4-heptanone, 2-octanone, 3-octano 4-octanone, 5-methyl-2-octanone, 2-nonanone, 3-nonanone, 4-nonanone, 5-nonanone, 2-decanone, 3-decanone, 4-decanone, 5-decanone, 2-undecanone, 3 -Undecanone, 4-undecanone, 5-undecanone, 6-undecanone, 2-methyl-4-undecanone, 2-dodecanone, 3-dodecanone, 4-dodecanone, 5-dodecanone, 6-dodecanone, 2-tetradecanone, 3-tetradecanone 8-pentadecanone, 10-nonadecanone, 7-tridecanone, 2-pentadecanone, 3-hexadecanone, 9-heptadecanone, 11-heneicosanone, 12-tricosanone, 14-heptacosanone, 16-hentriacontanone, 18-pentatriacontanone 4-ethoxy-2-butano 4- (4-methoxyphenyl) -2-butanone, 4-methoxy-4-methyl-2-pentanone, 4-methoxyphenylacetone, methoxyacetone, phenoxyacetone, methyl acetoacetate, ethyl acetoacetate, propylacetoacetate, Butyl acetoacetate, isobutyl acetoacetate, sec-butyl acetoacetate, tert-butyl acetoacetate, 3-pentyl acetoacetate, amyl acetoacetate, isoamyl acetoacetate, hexyl acetoacetate, heptyl acetoacetate, n-octyl acetoacetate, acetoacetic acid Benzyl, dimethyl acetyl succinate, dimethyl acetonylmalonate, diethyl acetonylmalonate, 2-methoxyethyl acetoacetate, allyl acetoacetate, 4-sec-butoxy-2-butanone, benzylbutylketone, bisdemethoxycurcumy 1,1-dimethoxy-3-butanone, 1,3-diacetoxyacetone, 4-hydroxyphenylacetone, 4- (4-hydroxyphenyl) -2-butanone, isoamylmethylketone, 4-hydroxy-2-butanone , 5-hexen-2-one, acetonylacetone, 3,4-dimethoxyphenylacetone, piperonylmethylketone, piperonylacetone, phthalimidoacetone, 4-isopropoxy-2-butanone, 4-isobutoxy-2- Examples include butanone, acetoxy-2-propanone, N-acetoacetylmorpholine, 1-acetyl-4-piperidone, and the like. Among these, acetone is preferable because solvent solubility when the obtained phenol compound is epoxidized is high and a cured product of the epoxy resin composition exhibits high thermal conductivity.

(In Formula (3), each R ₃ is independently present and is a hydrogen atom, an alkylcarbonyl group having 0 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or a carbon number. Represents an alkyl ester group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms or a hydroxyl group, n represents the number of carbon atoms, and represents an integer of 0, 1 or 2. m represents the number of R ₃ . And satisfies the relationship 1 ≦ m ≦ n + 2.)

In the formula (3), the case where R ₃ is a substituted or unsubstituted alkylcarbonyl group having 0 carbon atoms includes carbon atoms constituting the cycloalkane which is the main skeleton of the general formula (3). A carbonyl structure is shown, and examples thereof include 1,3-cyclopentanedione.

  Specific examples of the compound represented by the formula (3) used for the reaction with the compound represented by the formula (6) in order to obtain the phenol compound (a) include cyclopentanone and 3-phenylcyclopentanone. 2-acetylcyclopentanone, 1,3-cyclopentanedione, 2-methyl-1,3-cyclopentanedione, 2-ethyl-1,3-cyclopentanedione, cyclohexanone, 3-methylcyclohexanone, 4-methyl Cyclohexanone, 4-ethylcyclohexanone, 4-tert-butylcyclohexanone, 4-pentylcyclohexanone, 3-phenylcyclohexanone, 4-phenylcyclohexanone, 3,3-dimethylcyclohexanone, 3,4-dimethylcyclohexanone, 3,5-dimethylcyclohexanone, 4,4-dimethylsic Hexanone, 3,3,5-trimethylcyclohexanone, 2-acetylcyclohexanone, ethyl 4-cyclohexanonecarboxylate, 1,4-cyclohexanedione monoethylene ketal, bicyclohexane-4,4'-dione monoethylene ketal, 1,4- Cyclohexanedione mono-2,2-dimethyltrimethylene ketal, 2-acetyl-5,5-dimethyl-1,3-cyclohexanedione, 1,2-cyclohexanedione, 1,3-cyclohexanedione, 1,4-cyclohexanedione 2-methyl-1,3-cyclohexanedione, 5-methyl-1,3-cyclohexanedione, dimedone, dimethyl 1,4-cyclohexanedione-2,5-dicarboxylate, 4,4′-bicyclohexanone, 2, 2-bis (4-oxocyclo) Hexyl) propane, cycloheptanone, and the like. Among these, cyclopentanone, cyclohexanone, cycloheptanone, 4- (2), because the solvent solubility when the obtained phenol compound is epoxidized is high and the cured product of the epoxy resin composition exhibits high thermal conductivity. Methylcyclohexanone is preferred.

(In the formula (4), _{R 4} are present each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a hydroxyl group Represents one of these.)

In formula (4), each R ₄ is independently present and is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a hydroxyl group. Is preferred.

  Specific examples of the compound represented by the formula (4) used for the reaction with the compound represented by the formula (6) in order to obtain the phenol compound (a) include diacetyl, 2,3-pentanedione, 3 , 4-hexanedione, 5-methyl-2,3-hexanedione, 2,3-heptanedione, and the like. Of these, diacetyl is preferred because of high solvent solubility when the resulting phenol compound is epoxidized and high thermal conductivity of the cured product of the epoxy resin composition.

(In the formula (5), _{R 5} is present independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, 1 to 4 carbon atoms Represents an alkyl ester group of 10 to 10 or a hydroxyl group, and m is an integer of 1 to 10.)

In formula (5), R ₅ is independently present and is preferably a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a hydroxyl group.

  Specific examples of the compound represented by the formula (5) used for the reaction with the compound represented by the formula (6) in order to obtain the phenol compound (a) include ethyl diacetate acetate and 2,5-hexanedione. 3-methyl-2,4-pentanedione, 3-ethyl-2,4-pentanedione, 3-butyl-2,4-pentanedione, 3-phenyl-2,4-pentanedione, 4-acetyl-5 -Ethyl oxohexanoate and the like. Among these, since the solvent solubility at the time of epoxidizing the phenol compound obtained is high and the cured product of the epoxy resin composition exhibits high thermal conductivity, 3-methyl-2,4-pentanedione, 3 -Ethyl-2,4-pentanedione is preferred.

(In formula (6), each R ₆ is independently present and is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a hydroxyl group, a nitro group, a formyl group, an allyl group, or carbon. Represents any one of the alkoxy groups of formula 1 to 10. k represents the number of R ₆ and is an integer of 1 to 4)

In the above formula (6), each R ₆ is independently present and is preferably an alkoxy group having 1 to 3 carbon atoms.

  In order to obtain a phenol compound (a), as a specific example of the compound represented by Formula (6) used for reaction with 1 or more types chosen from the compound represented by Formula (1)-(5), For example, 2-hydroxybenzaldehyde, 3-hydroxybenzaldehyde, 4-hydroxybenzaldehyde, 2,3-dihydroxybenzaldehyde, 2,4-dihydroxybenzaldehyde, 2,5-dihydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde, syringaldehyde, 3 , 5-di-tert-butyl-4-hydroxybenzaldehyde, isovanillin, 4-hydroxy-3-nitrobenzaldehyde, 5-hydroxy-2-nitrobenzaldehyde, 3,4-dihydroxy-5-nitrobenzaldehyde, vanillin, o-vanillin 2-Hido Roxy-1-naphthaldehyde, 2-hydroxy-5-nitro-m-anisaldehyde, 2-hydroxy-5-methylisophthalaldehyde, 2-hydroxy-4-methoxybenzaldehyde, 1-hydroxy-2-naphthaldehyde, 2- Hydroxy-5-methoxybenzaldehyde, 5-nitrovanillin, 5-allyl-3-methoxysalicylaldehyde, 3,5-di-tert-butylsalicylaldehyde, 3-ethoxysalicylaldehyde, 4-hydroxyisophthalaldehyde, 4-hydroxy- 3,5-dimethylbenzaldehyde, 2,4,6-trihydroxybenzaldehyde, 2,4,5-trihydroxybenzaldehyde, 2,3,4-trihydroxybenzaldehyde, 3,4,5-trihydroxybenzaldehyde, 3 Ethoxy-4-hydroxybenzaldehyde, and the like. These may use only 1 type or may use 2 or more types together. Among these, it is preferable to use vanillin alone, because the solvent solubility when the obtained phenol compound is epoxidized is high, and the cured product of the epoxy resin composition exhibits particularly high thermal conductivity.

The phenol compound (a) is obtained by an aldol condensation reaction between one or more compounds represented by the formulas (1) to (5) and a compound represented by the formula (6) under acidic conditions or basic conditions. .
The compound represented by the formula (6) is 1.0 to 1.05 mol, the formula (2), the formula (3), the formula (4) and the formula (1) with respect to 1 mol of the compound represented by the formula (1). 2.0-3.15 mol is used with respect to 1 mol of compounds represented by 5).

  When the aldol condensation reaction is performed under acidic conditions, examples of the acidic catalyst that can be used include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as toluenesulfonic acid, xylenesulfonic acid, and oxalic acid. These may be used alone or in combination of a plurality of types. The usage-amount of an acidic catalyst is 0.01-1.0 mol with respect to 1 mol of compounds represented by Formula (6), Preferably it is 0.2-0.5 mol.

  On the other hand, when the aldol condensation reaction is performed under basic conditions, usable basic catalysts include metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as potassium carbonate and sodium carbonate, diethylamine, Examples include amine derivatives such as triethylamine, tributylamine, diisobutylamine, pyridine and piperidine, and amino alcohol derivatives such as dimethylaminoethyl alcohol and diethylaminoethyl alcohol. Also in the case of basic conditions, the basic catalysts listed above may be used alone, or a plurality of types may be used in combination. The usage-amount of a basic catalyst is 0.1-2.5 mol with respect to 1 mol of compounds represented by Formula (6), Preferably it is 0.2-2.0 mol.

  In the reaction for obtaining the phenol compound (a), a solvent may be used as necessary. The solvent that can be used is not particularly limited as long as it does not have reactivity with the compound represented by the formula (6) such as ketones, but the compound represented by the formula (6) as a raw material can be easily used. It is preferable to use alcohols as the solvent in terms of dissolution in the solvent.

  The reaction temperature is usually 10 to 90 ° C, preferably 35 to 70 ° C. Although reaction time is 0.5 to 10 hours normally, since there is a difference in reactivity with the kind of raw material compound, it is not this limitation. When taking out as a resin after completion | finish of reaction, an unreacted substance, a solvent, etc. are removed from a reaction liquid under heating and pressure reduction, after washing | cleaning a reaction substance without water washing. When taking out with a crystal | crystallization, a crystal | crystallization is deposited by dripping a reaction liquid in a lot of water. When the reaction is carried out under basic conditions, the produced phenolic compound of the present invention may dissolve in water, so that it is precipitated as crystals under neutral to acidic conditions by adding hydrochloric acid or the like.

  The phenol compound (b) has the following formula (7)

（式中、Ｒ_７、ＸおよびＹは独立して存在し、水素原子、炭素数１〜１０のアルキル基もしくはアリール基、水酸基、又は炭素数１〜１０のアルコキシ基のいずれかを表す。ｋはＲ_７の数を表し、１〜４の整数を表す。）で表される。

(In formula, R < ₇ >, X and Y exist independently and represent either a hydrogen atom, a C1-C10 alkyl group or aryl group, a hydroxyl group, or a C1-C10 alkoxy group. K Represents the number of R ₇ and represents an integer of 1 to 4.

In the formula (7), R ₇ , X and Y are independently present from the viewpoint of maintaining high thermal conductivity, and are preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

Various bisphenols are mentioned as a phenolic compound (b). Specifically, BPF, BPA, BPE, Methylenebis-p-CR, TM-BPF, Bis-C, BisP-MIBK, Bis26X-A, BisP-AP, BisOPP-A, UltimateP, DHBP, BisOC-F, BisP- B, BisP-IBTD, Bis-BA, BisP-IOTD, BisOIPP-A, BisP-DED, BisOSBP-A, BisOTBP-A, Bis2M6B-IBTD, BisOCHP-A, Ph-CC-AP (all manufactured by Honshu Chemical Industry) ) And the like.
Among these, BPF and BPA are preferable from the viewpoint of maintaining high thermal conductivity, and BPF is particularly preferable.

  The phenol compound (c) has the following formula (8)

（式中、Ｒ_８、およびＡは独立して存在し、Ｒ_８は水素原子、炭素数１〜１０のアルキル基もしくはアリール基、水酸基、又は炭素数１〜１０のアルコキシ基のいずれかを表す。ｌはＲ_８の数を表し、１〜４の整数を表す。Ａは直接結合、もしくはシクロ環を有する炭素数５〜１５のアルキリデン基を表す。）で表される。

(In formula, R < ₈ > and A exist independently, R < ₈ > represents either a hydrogen atom, a C1-C10 alkyl group or aryl group, a hydroxyl group, or a C1-C10 alkoxy group. L represents the number of R ₈ and represents an integer of 1 to 4. A represents a direct bond or an alkylidene group having 5 to 15 carbon atoms having a cyclo ring.

Examples of the phenolic compound (c) include biphenyl having a direct bond at the position A and 3,3 ′, 5,5′-tetramethyl-4,4′-biphenol compound, and corresponding cyclic fats. And phenol compounds obtained by reacting a group ketone with a phenol.
Specific compounds include the following compounds.

前記フェノール化合物は市販品が入手可能で、例えばＢｉｓＰ−ＣＰ、ＢｉｓＰ−Ｚ、ＢｉｓＰ−ＴＭＣ、ＢｉｓＯＣ−ＴＭＣ、ＢｉｓＰ−ＭＺ、ＢｉｓＰ−３ＭＺ、ＢｉｓＰ−ＩＰＺ、ＢｉｓＣＲ−ＩＰＺ、Ｂｉｓ２６Ｘ−ＩＰＺ、ＢｉｓＰ−ＴＣＤ、ＢｉｓＯＣ−ＣＤＥ、Ｂｉｓ２６Ｘ−ＣＤＥ、ＢｉｓＰ−ＣＨＥＰ、ＢｉｓＰ−ＣＯＣＴ、ＢｉｓＰ−ＣＰｅＤＥ（いずれも本州化学工業製）、ＴＣＤＢＰ（ＭＥＴＲＯＰＯＲＩＴＡＮ
ＥＸＩＭＣＨＥＭ ＸＴＤ）などが挙げられる。

The phenol compound is commercially available, for example, BisP-CP, BisP-Z, BisP-TMC, BisOC-TMC, BisP-MZ, BisP-3MZ, BisP-IPZ, BisCR-IPZ, Bis26X-IPZ, BisP- TCD, BisOC-CDE, Bis26X-CDE, BisP-CHEP, BisP-COCT, BisP-CPeDE (all manufactured by Honshu Chemical Industry), TCDBP (METROPOLITAN
EXIMCHEM XTD).

Next, the epoxy resin mixture of the present invention will be described.
The epoxy resin mixture of the present invention can be obtained by reacting each of the above-described phenol compounds with epihalohydrin and epoxidizing it. In the case of epoxidation, each phenol compound (a) to (c) may be reacted in advance with an epihalohydrin to obtain epoxy resins (A) to (C), and each epoxy resin may be mixed. I do not care. As a method of reacting each of the phenol compounds with epihalohydrin, any known method can be used without any particular limitation. Specific examples thereof include those described in JP-A Nos. 05-155978 and 2008-179739. This method can be used.
However, from the viewpoint of production, it is preferable to react an epihalohydrin with a mixture of phenol compounds (a) to (c) to obtain an epoxy resin mixture. By setting it as the said manufacturing method, the mixture of epoxy resin (A)-(C) can be obtained, and also the skeleton of each phenol compound (a)-(c) is connected with the glycidyl group which opened the ring. Epoxy resin is also produced.
As the epoxy resin mixture of the present invention, a cured product having a particularly low melt viscosity and a high thermal conductivity can be obtained. Therefore, the compound represented by the formula (6) and the compound represented by the formula (3) A mixture containing the epoxy resin (A), which is an epoxidized product of the phenol compound (a) obtained by the reaction, and further containing the epoxy resin (B) and / or the epoxy resin (C) is preferable.

Hereinafter, a method of obtaining an epoxy resin mixture by reacting a mixture of phenolic compounds (a) to (c) with epihalohydrin will be described.
The sum of the amounts of the phenolic compound (b) and the phenolic compound (c) in the total amount of the phenolic compounds (a) to (c) is preferably 1 to 30% by mass, more preferably 5 to 30% by mass. When the ratio of the sum of the amounts of the phenol compound (b) and the phenol compound (c) is large, the thermal conductivity is low, and when the ratio is small, the viscosity is high and the adhesion to the metal is poor.

  In the reaction for obtaining the epoxy resin contained in the epoxy resin mixture of the present invention, epichlorohydrin, α-methylepichlorohydrin, β-methylepichlorohydrin, epibromohydrin, etc. can be used as the epihalohydrin, but epichlorohydrin is easily available industrially. Is preferred. The usage-amount of epihalohydrin is 2-20 mol normally with respect to 1 mol of hydroxyl groups of a phenol compound, Preferably it is 2-15 mol, Most preferably, it is 2-6.5 mol. The epoxy resin is obtained by a reaction in which a phenol compound and an epihalohydrin are added in the presence of an alkali metal oxide, and then the resulting 1,2-halohydrin ether group is cyclized and epoxidized. At this time, by using epihalohydrin in an amount significantly smaller than usual as described above, the molecular weight of the epoxy resin can be increased and the molecular weight distribution can be broadened. As a result, the resulting epoxy resin can be removed from the system as a resinous material having a relatively low softening point, and exhibits excellent solvent solubility.

Examples of the alkali metal hydroxide that can be used for the epoxidation reaction include sodium hydroxide, potassium hydroxide, and the like, and these may be used as they are, or an aqueous solution thereof may be used. When using an aqueous solution, the aqueous solution of the alkali metal hydroxide is continuously added to the reaction system and separated from a mixture of water and epihalohydrin distilled continuously under reduced pressure or normal pressure. Alternatively, water may be removed and only the epihalohydrin is continuously returned to the reaction system. The amount of the alkali metal hydroxide used is usually 0.9 to 3.0 mol, preferably 1.0 to 2.5 mol, more preferably 1.0 to 2.0 mol per mol of the hydroxyl group of the phenol compound. Mol, particularly preferably 1.0 to 1.3 mol.
Further, the present inventors remarkably reduce the amount of halogen contained in the epoxy resin obtained by using flaky sodium hydroxide in the epoxidation reaction, rather than using sodium hydroxide as an aqueous solution. It came to know that it became possible. This halogen is derived from epihalohydrin, and the more it is mixed in the epoxy resin, the lower the thermal conductivity of the cured product. Further, the flaky sodium hydroxide is preferably added in portions in the reaction system. By performing the divided addition, it is possible to prevent a rapid decrease in the reaction temperature, thereby preventing the formation of impurities such as 1,3-halohydrin and halomethylene, and a cured product with higher thermal conductivity. Can be formed.

  In order to accelerate the epoxidation reaction, it is preferable to add a quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide, trimethylbenzylammonium chloride as a catalyst. The amount of the quaternary ammonium salt used is usually 0.1 to 15 g, preferably 0.2 to 10 g, per 1 mol of the hydroxyl group of the phenol compound of the present invention.

  In addition, during the epoxidation, it is preferable for the reaction to proceed by adding an aprotic polar solvent such as alcohols such as methanol, ethanol and isopropyl alcohol, dimethyl sulfone, dimethyl sulfoxide, tetrahydrofuran and dioxane. Of these, alcohols or dimethyl sulfoxide are preferable. When alcohols are used, an epoxy resin can be obtained with a high yield. On the other hand, when dimethyl sulfoxide is used, the halogen content in the epoxy resin can be further reduced.

  When using the said alcohol, the usage-amount is 2-50 mass% normally with respect to the usage-amount of an epihalohydrin, Preferably it is 4-35 mass%. Moreover, when using an aprotic polar solvent, it is 5-100 mass% normally with respect to the usage-amount of epihalohydrin, Preferably it is 10-80 mass%.

The reaction temperature is usually 30 to 90 ° C, preferably 35 to 80 ° C. The reaction time is usually 0.5 to 10 hours, preferably 1 to 8 hours.
After completion of the reaction, the reaction product is washed with water or without washing with water, and the epihalohydrin, the solvent and the like are removed from the reaction solution under heating and reduced pressure. In order to further reduce the amount of halogen contained in the obtained epoxy resin, the recovered epoxy resin mixture of the present invention is dissolved in a solvent such as toluene or methyl isobutyl ketone, and an alkali such as sodium hydroxide or potassium hydroxide is dissolved. The reaction can be carried out by adding an aqueous solution of metal hydroxide to ensure ring closure. In this case, the usage-amount of an alkali metal hydroxide is 0.01-0.3 mol normally with respect to 1 mol of hydroxyl groups of the phenolic compound of this invention, Preferably it is 0.05-0.2 mol. The reaction temperature is usually 50 to 120 ° C., and the reaction time is usually 0.5 to 2 hours.

  After completion of the reaction, the produced salt is removed by filtration, washing with water, etc., and the solvent is distilled off under heating and reduced pressure to obtain the epoxy resin mixture of the present invention. When the epoxy resin mixture of the present invention is precipitated as crystals, the crystals of the epoxy resin mixture may be filtered after dissolving the salt produced in a large amount of water.

As described above, the total halogen content of the epoxy resin mixture of the present invention obtained by using flaky sodium hydroxide is usually 1800 ppm or less, preferably 1600 ppm or less, more preferably 700 ppm or less. If the total halogen content is too large, the electrical reliability of the cured product will be adversely affected, and it will remain as an uncrosslinked end, so the orientation of the molecules in the molten state during curing will not proceed and the thermal conductivity Leading to a decline.
The epoxy equivalent of the epoxy resin mixture of the present invention is 350 g / eq. From the viewpoint of obtaining a low-viscosity epoxy resin mixture. The following are preferred, especially 300 g / eq. The following is preferred.
In addition, the epoxy equivalent of the epoxy resin mixture of this invention shows the average value of the epoxy equivalent of each epoxy resin contained in the obtained epoxy resin mixture.

  Hereinafter, the epoxy resin composition of the present invention will be described. The epoxy resin composition of the present invention contains the epoxy resin mixture of the present invention as an essential component.

  In the epoxy resin composition of the present invention, the epoxy resin mixture of the present invention can be used in combination with other epoxy resins.

Specific examples of other epoxy resins include phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene, dihydroxynaphthalene, etc.) and various aldehydes (formaldehyde, acetaldehyde, Alkyl aldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, cinnamaldehyde, etc.), polycondensates of aromatic compounds such as xylene and formaldehyde polycondensates and phenols Polycondensates, phenols and various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norvol Polymers with diene, vinyl norbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.), phenols and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.) Polycondensates, polycondensates of phenols and aromatic dimethanols (benzene dimethanol and biphenyl dimethanol, etc.), phenols and aromatic dichloromethyls (α, α'-dichloroxylene, bischloromethyl biphenyl, etc.) ), Polycondensates of phenols and aromatic bisalkoxymethyls (bismethoxymethylbenzene, bismethoxymethylbiphenyl, bisphenoxymethylbiphenyl, etc.), bisphenols and each Examples include polycondensates of seed aldehydes, glycidyl ether epoxy resins obtained by glycidylation of alcohols, alicyclic epoxy resins, glycidyl amine epoxy resins, glycidyl ester epoxy resins, etc. If there is, it is not limited to these. These may be used alone or in combination of two or more.
When other epoxy resins are used in combination, the proportion of the epoxy resin mixture of the present invention in the total epoxy resin component in the epoxy resin composition of the present invention is preferably 30% by mass or more, more preferably 40% by mass or more, and 70% by mass. % Or more is more preferable, and 100% by mass (when no other epoxy resin is used in combination) is particularly preferable. However, when using the epoxy resin mixture of this invention as a modifier of an epoxy resin composition, it adds in the ratio used as 1-30 mass% in all the epoxy resins.

Examples of the curing agent contained in the epoxy resin composition of the present invention include amine compounds, acid anhydride compounds, amide compounds, and phenol compounds. Specific examples of these other curing agents are shown in the following (a) to (e).
(A) Amine-based compounds diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, naphthalenediamine, etc. (b) acid anhydride-based compounds phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride , Tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methyl nadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, etc. (c) Amide compounds Dicyandiamide or linolenic acid dimer and ethylenediamine Polyamide resin, etc.

(D) Phenol compound polyhydric phenols (bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, terpene diphenol, 4,4′-dihydroxybiphenyl, 2,2′-dihydroxybiphenyl, 3,3 ′, 5, 5'-tetramethyl- (1,1'-biphenyl) -4,4'-diol, hydroquinone, resorcin, naphthalenediol, tris- (4-hydroxyphenyl) methane and 1,1,2,2-tetrakis (4 -Hydroxyphenyl) ethane and the like; phenols (eg, phenol, alkyl-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene and dihydroxynaphthalene) and aldehydes (formaldehyde, acetaldehyde, benzaldehyde, p-hydro) Phenol resins obtained by condensation with benzaldehyde, o-hydroxybenzaldehyde, furfural, etc.), ketones (p-hydroxyacetophenone, o-hydroxyacetophenone, etc.), or dienes (dicyclopentadiene, tricyclopentadiene, etc.); Phenols and substituted biphenyls (such as 4,4′-bis (chloromethyl) -1,1′-biphenyl and 4,4′-bis (methoxymethyl) -1,1′-biphenyl), or substituted phenyls ( Phenol resins obtained by polycondensation with 1,4-bis (chloromethyl) benzene, 1,4-bis (methoxymethyl) benzene, 1,4-bis (hydroxymethyl) benzene and the like; Or a modified product of the phenol resin; Lumpur A and halogenated phenols such as brominated phenol resin (e) Other imidazoles, BF ₃ ^- amine complex, guanidine derivatives

  Among these curing agents, active hydrogen groups such as amine compounds such as diaminodiphenylmethane, diaminodiphenylsulfone and naphthalenediamine, and condensates of catechol and aldehydes, ketones, dienes, substituted biphenyls or substituted phenyls. A phenol compound (a) which is a precursor of the epoxy resin (A), which is one component of the present invention, in addition to a curing agent having a structure in which is adjacent to each other contributes to the arrangement of the epoxy resin.

  In the epoxy resin composition of the present invention, the amount of the curing agent used is preferably 0.8 to 1.2 equivalents, particularly preferably 0.95 to 1.05, with respect to 1 equivalent of epoxy groups of the epoxy resin.

The epoxy resin composition of the present invention can impart further excellent high heat conductivity to the cured product by containing an inorganic filler excellent in heat conduction as required.
The inorganic filler contained in the epoxy resin composition of the present invention is added for the purpose of imparting higher thermal conductivity to the cured product of the epoxy resin composition, and the thermal conductivity of the inorganic filler itself is too low. In some cases, the high thermal conductivity obtained by the combination of the epoxy resin and the curing agent may be impaired. Therefore, as the inorganic filler contained in the epoxy resin composition of the present invention, the one having higher thermal conductivity is preferable, usually 20 W / m · K or more, preferably 30 W / m · K or more, more preferably 50 W / m. -There is no restriction as long as it has a thermal conductivity of K or higher. In addition, heat conductivity here is the value measured by the method based on ASTM E1530. Specific examples of inorganic fillers having such characteristics include inorganic powder fillers such as boron nitride, aluminum nitride, silicon nitride, silicon carbide, titanium nitride, zinc oxide, tungsten carbide, alumina, magnesium oxide, synthetic fibers, Examples thereof include fibrous fillers such as ceramic fibers, and coloring agents. The shape of these inorganic fillers may be any of powder (bulk shape, spherical shape), single fiber, long fiber, etc. However, in particular, if it is a flat plate, the cured product is cured by the lamination effect of the inorganic filler itself. This is preferable because the thermal conductivity becomes higher and the heat dissipation of the cured product is further improved.
Although the usage-amount of the inorganic filler in the epoxy resin composition of this invention is 2-1000 mass parts normally with respect to 100 mass parts of resin components in an epoxy resin composition, in order to raise heat conductivity as much as possible. It is preferable to increase the amount of the inorganic filler as much as possible as long as the handling of the epoxy resin composition of the present invention in a specific application is not hindered. These inorganic fillers may be used alone or in combination of two or more.

  In addition, if the thermal conductivity of the entire filler can be maintained at 20 W / m · K or more, the thermal conductivity of the inorganic filler with 20 W / m · K or more is less than 20 W / m · K. However, for the purpose of the present invention to obtain a cured product having as high a thermal conductivity as possible, the use of a filler having a thermal conductivity of less than 20 W / m · K is minimal. Should be kept on. There is no particular limitation on the type and shape of the filler that can be used in combination.

  When the epoxy resin composition of the present invention is used for semiconductor sealing applications, heat conduction is performed at a ratio of 75 to 93% by mass in the epoxy resin composition in terms of heat resistance, moisture resistance, mechanical properties, etc. of the cured product. It is preferable to use an inorganic filler having a rate of 20 W / m · K or more. In this case, the balance is an epoxy resin component, a curing agent component, and other additives that are added as necessary. Examples of the additive include other inorganic fillers that can be used in combination and a curing accelerator that will be described later.

  The epoxy resin composition of the present invention may contain a curing accelerator. Examples of the curing accelerator that can be used include imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole and 2-ethyl-4-methylimidazole, 2- (dimethylaminomethyl) phenol, triethylenediamine, Tertiary amines such as triethanolamine and 1,8-diazabicyclo (5,4,0) undecene-7, organic phosphines such as triphenylphosphine, diphenylphosphine and tributylphosphine, metal compounds such as tin octylate, Tetrasubstituted phosphonium tetrasubstituted borates such as tetraphenylphosphonium tetraphenylborate and tetraphenylphosphonium ethyltriphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate and N Such as tetraphenyl boron salts such methylmorpholine tetraphenylborate and the like. 0.01-15 mass parts is used for a hardening accelerator as needed with respect to 100 mass parts of epoxy resins.

  If necessary, various compounding agents such as a silane coupling agent, a release agent and a pigment, various thermosetting resins, various thermoplastic resins, and the like can be added to the epoxy resin composition of the present invention. Specific examples of thermosetting resins and thermoplastic resins include vinyl ester resins, unsaturated polyester resins, maleimide resins, cyanate resins, isocyanate compounds, benzoxazine compounds, vinyl benzyl ether compounds, polybutadiene and its modified products, and acrylonitrile. Examples include modified polymers, indene resins, fluororesins, silicone resins, polyetherimides, polyethersulfones, polyphenylene ethers, polyacetals, polystyrenes, polyethylenes, and dicyclopentadiene resins. The thermosetting resin or thermoplastic resin is used in an amount occupying 60% by mass or less in the epoxy resin composition of the present invention.

The epoxy resin composition of the present invention can be obtained by uniformly mixing the above-mentioned components, and preferred applications thereof include semiconductor encapsulants and printed wiring boards.
The epoxy resin composition of the present invention can be easily made into a cured product by the same method as conventionally known. For example, an epoxy resin that is an essential component of the epoxy resin composition of the present invention, a curing agent, an inorganic filler having a thermal conductivity of 20 W / m · K or more, and a curing accelerator, a compounding agent, and various thermosetting resins as necessary. And various thermoplastic resins, etc., if necessary, using an extruder, kneader or roll, etc., until the mixture is sufficiently mixed until uniform, the melt casting method or transfer molding A cured product of the epoxy resin composition of the present invention can be obtained by molding by a method, an injection molding method, a compression molding method, or the like, and further heating for 2 to 10 hours above the melting point. By sealing the semiconductor element mounted on the lead frame or the like by the above-described method, the epoxy resin composition of the present invention can be used for semiconductor sealing applications.

Moreover, the epoxy resin composition of this invention can also be made into the varnish containing a solvent. The varnish includes, for example, at least the epoxy resin mixture of the present invention, and optionally includes a mixture containing other components such as an inorganic filler having a thermal conductivity of 20 W / m · K or more, toluene, xylene, acetone, Methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, N, N′-dimethylformamide, N, N′-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dipropylene glycol dimethyl ether, Glycol ethers such as dipropylene glycol diethyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, ethyl acetate, butyl acetate, methyl cellosolve acetate , Ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, propylene glycol monomethyl ether acetate, esters such as dialkyl glutarate, dialkyl succinate, dialkyl adipate, cyclic esters such as γ-butyrolactone, petroleum ether, petroleum naphtha It can be obtained by mixing with an organic solvent such as a petroleum solvent such as hydrogenated petroleum naphtha and solvent naphtha. The amount of the solvent is usually 10 to 95% by mass, preferably 15 to 85% by mass with respect to the whole varnish.
The varnish obtained as described above is impregnated into a fiber substrate such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber and paper, and then the solvent is removed by heating, and the epoxy resin composition of the present invention By making a semi-cured state, the prepreg of the present invention can be obtained. Here, the “semi-cured state” means a state in which an epoxy group which is a reactive functional group partially remains unreacted. The prepreg can be hot press molded to obtain a cured product.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. In the synthesis examples, examples, and comparative examples, “part” means “part by mass”.
The epoxy equivalent, ICI viscosity, and thermal conductivity were measured under the following conditions.
-Epoxy equivalent Measured by the method described in JIS K-7236, the unit is g / eq. It is.
Melt viscosity Melt viscosity by cone plate method at 150 ° C. Measuring instrument: Cone plate (ICI) high temperature viscometer (manufactured by RESEACH EQUIIPMENT (LONDON) LTD.)
-Thermal conductivity It measures by the method based on ASTM E1530, and a unit is W / m * K.

Synthesis example 1
A flask equipped with a stirrer, a reflux condenser, and a stirrer was charged with 136 parts of 4′-hydroxyacetophenone, 152 parts of vanillin and 200 parts of ethanol and dissolved. After adding 20 parts of 97 mass% sulfuric acid to this, it heated up to 60 degreeC, and after reacting at this temperature for 10 hours, the reaction liquid was inject | poured into 1200 parts of water, and was crystallized. The crystals were separated by filtration, washed twice with 600 parts of water, and then vacuum-dried to obtain 256 parts of phenol compound 1 as yellow crystals. The endothermic peak temperature of the obtained crystal as measured by DSC was 233 ° C.

Synthesis example 2
In a flask equipped with a stirrer, a reflux condenser, and a stirrer, 166 parts of 4′-hydroxy-3′-methoxyacetophenone, 122 parts of 4-hydroxybenzaldehyde, and 200 parts of ethanol were charged and dissolved. After adding 20 parts of 97% sulfuric acid thereto, the temperature was raised to 50 ° C., and after reacting at this temperature for 10 hours, the reaction solution was poured into 1200 parts of water for crystallization. The crystals were separated by filtration, washed twice with 600 parts of water, and then vacuum-dried to obtain 285 parts of phenol compound 2 as brown crystals. The endothermic peak temperature of the obtained crystal as measured by DSC was 193 ° C.

Synthesis example 3
In a flask equipped with a stirrer, a reflux condenser, and a stirrer, 56 parts of 4-methylcyclohexanone, 152 parts of vanillin and 150 parts of ethanol were charged and dissolved. After adding 10 parts of 97 mass% sulfuric acid, the temperature was raised to 50 ° C., and after reacting at this temperature for 10 hours, 25 parts of sodium tripolyphosphate was added and stirred for 30 minutes. Thereafter, 500 parts of methyl isobutyl ketone (MIBK) was added, followed by washing twice with 200 parts of water, and then the solvent was distilled off with an evaporator to obtain 304 parts of semi-solid phenol compound 3.

Synthesis example 4
A flask equipped with a stirrer, a reflux condenser, and a stirrer was charged with 29 parts of acetone, 152 parts of vanillin and 300 parts of ethanol and dissolved. After adding 80 parts of 50% aqueous sodium hydroxide solution to this, the temperature was raised to 45 ° C., and after reacting at this temperature for 120 hours, the reaction solution was poured into 800 mL of 1.5N hydrochloric acid for crystallization. The crystals were separated by filtration, washed twice with 600 parts of water, and then vacuum-dried to obtain 165 parts of phenol compound 4 as yellow crystals. The melting point of the obtained crystal was 201 ° C. by DSC measurement.

Example 1
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with nitrogen purge, 80 parts of phenol compound 1 obtained in Synthesis Example 1, 20 parts of 4,4′-biphenol, 300 parts of epichlorohydrin, dimethyl sulfoxide ( Hereafter, 75 parts of DMSO) was added, heated to 70 ° C. with stirring, dissolved, 33 parts of flaky sodium hydroxide was added in portions over 90 minutes, and then reacted for 2.5 hours at 70 ° C. Was done. After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 290 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., added with 9 parts of 30% aqueous sodium hydroxide solution with stirring, reacted for 1 hour, and then washed with water until the washing water became neutral. 130 parts of epoxy resin mixture 1 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 200 g / eq. The melt viscosity was 0.03 Pa · s.

Example 2
While purging a flask equipped with a stirrer, a reflux condenser and a stirrer with nitrogen, 80 parts of the phenol compound 2 obtained in Synthesis Example 2, 20 parts of 4,4′-biphenol, 300 parts of epichlorohydrin, and 75 parts of DMSO were added. In addition, the temperature was raised to 70 ° C. with stirring, and the mixture was dissolved. 33 parts of flaky sodium hydroxide was added in portions over 90 minutes, and then the reaction was performed for 2.5 hours at 70 ° C. After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 290 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., added with 9 parts of 30% aqueous sodium hydroxide solution with stirring, reacted for 1 hour, and then washed with water until the washing water became neutral. 130 parts of epoxy resin mixture 2 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 201 g / eq. The melt viscosity was 0.03 Pa · s.

Example 3
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with nitrogen, 80 parts of the phenol compound 3 obtained in Synthesis Example 3, 20 parts of 4,4′-biphenol, 235 parts of epichlorohydrin, and 59 parts of DMSO were added. In addition, with stirring, the temperature was raised to 45 ° C., dissolved, and 26 parts of flaky sodium hydroxide were added in portions over 90 minutes, then kept at 45 ° C. for 1.5 hours, and then raised to 70 ° C. The reaction was performed for 30 minutes. After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 271 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., 8 parts of 30% aqueous sodium hydroxide solution was added with stirring, and the reaction was performed for 1 hour, followed by washing with water until the washing water became neutral. 122 parts of epoxy resin mixture 3 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 235 g / eq. The melt viscosity was 0.03 Pa · s.

Example 4
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with nitrogen purge, 80 parts of the phenol compound 4 obtained in Synthesis Example 4, 20 parts of 4,4′-biphenol, 261 parts of epichlorohydrin, and 65 parts of DMSO were added. In addition, with stirring, the temperature was raised to 45 ° C., dissolved, and 29 parts of flaky sodium hydroxide was added in portions over 90 minutes, then kept at 45 ° C. for 1.5 hours, and then raised to 70 ° C. The reaction was performed for 30 minutes. After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 279 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., 8 parts of 30% aqueous sodium hydroxide solution was added with stirring, and the reaction was performed for 1 hour, followed by washing with water until the washing water became neutral. 126 parts of epoxy resin mixture 4 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 220 g / eq. The melt viscosity was 0.03 Pa · s.

Example 5
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with a nitrogen purge, 90 parts of the phenol compound 1 obtained in Synthesis Example 1, 10 parts of bisphenol F (BPF), 284 parts of epichlorohydrin, dimethyl sulfoxide (hereinafter referred to as the following) , DMSO) was added, heated to 70 ° C. with stirring, dissolved, 32 parts of flaky sodium hydroxide was added in portions over 90 minutes, and the reaction was continued for 2.5 hours at 70 ° C. I did it. After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 286 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., added with 9 parts of 30% aqueous sodium hydroxide solution with stirring, reacted for 1 hour, and then washed with water until the washing water became neutral. 128 parts of epoxy resin mixture 5 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 204 g / eq. The melt viscosity was 0.03 Pa · s.

Example 6
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with nitrogen purge, 90 parts of phenol compound 2 obtained in Synthesis Example 2, 10 parts of BPF, 284 parts of epichlorohydrin, and 71 parts of DMSO were added, and while stirring, The mixture was heated to 70 ° C., dissolved, and 32 parts of flaky sodium hydroxide were added in portions over 90 minutes, and then reacted at 70 ° C. for 2.5 hours. After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 286 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., added with 9 parts of 30% aqueous sodium hydroxide solution with stirring, reacted for 1 hour, and then washed with water until the washing water became neutral. 129 parts of epoxy resin mixture 6 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 205 g / eq. The melt viscosity was 0.03 Pa · s.

Example 7
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with nitrogen purge, 90 parts of phenol compound 3 obtained in Synthesis Example 3, 10 parts of BPF, 212 parts of epichlorohydrin, and 53 parts of DMSO were added, and 45 parts under stirring. The solution was heated up to 0 ° C., dissolved, and 24 parts of flaky sodium hydroxide was added in portions over 90 minutes, and then the temperature was kept at 45 ° C. for 1.5 hours, then heated to 70 ° C. and reacted for 30 minutes. . After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 264 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., 7 parts of 30% aqueous sodium hydroxide solution was added with stirring, and the reaction was performed for 1 hour, followed by washing with water until the washing water became neutral. 119 parts of epoxy resin mixture 7 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 250 g / eq. The melt viscosity was 0.03 Pa · s.

Example 8
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with nitrogen purge, 90 parts of the phenol compound 4 obtained in Synthesis Example 4, 10 parts of BPF, 241 parts of epichlorohydrin, and 60 parts of DMSO were added, and 45 parts under stirring. The mixture was heated to 50 ° C., dissolved, and 27 parts of flaky sodium hydroxide was added in portions over 90 minutes, and then the mixture was heated at 45 ° C. for 1.5 hours, then heated to 70 ° C. and reacted for 30 minutes. . After completion of the reaction, excess solvent such as epichlorohydrin was distilled off under reduced pressure at 135 ° C. using a rotary evaporator. The residue was dissolved in 273 parts of MIBK and then washed with water to remove the salt. After washing with water, the MIBK solution was heated to 70 ° C., 7 parts of 30% aqueous sodium hydroxide solution was added with stirring, and the reaction was performed for 1 hour, followed by washing with water until the washing water became neutral. 123 parts of epoxy resin mixture 8 was obtained by distilling off methyl isobutyl ketone etc. under reduced pressure at 180 ° C. using a rotary evaporator. The epoxy equivalent of the obtained epoxy resin mixture was 229 g / eq. The melt viscosity was 0.03 Pa · s.

Examples 9 to 24 and Comparative Examples 1 and 2
Various components are blended in the proportions (parts) shown in Table 1, kneaded with a mixing roll, converted into a tablet, a resin molded product is prepared by transfer molding, heated at 160 ° C. for 2 hours, and further heated at 180 ° C. for 8 hours. Hardened | cured material of the epoxy resin composition of invention and the resin composition for a comparison was obtained. The results of measuring the thermal conductivity of these cured products are shown in Table 1.

  Epoxy resin 9: Epoxy resin represented by the following formula (9) (trade name: NC-3000, Nippon Kayaku Epoxy equivalent 276 g / eq.)

  Epoxy resin 10: a biphenyl type epoxy resin containing an equimolar amount of an epoxy resin represented by the following formulas (10) and (11) (trade name: YL-6121H manufactured by Japan Epoxy Resin, epoxy equivalent of 175 g / eq.)

Curing agent 1: phenol compound 1 obtained in Synthesis Example 1
Curing agent 2: phenol compound 2 obtained in Synthesis Example 2
Curing agent 3: phenolic compound 3 obtained in Synthesis Example 3
Curing agent 4: phenol compound 4 obtained in Synthesis Example 4
Curing agent 5: phenol novolak represented by the following formula (12) (trade name: H-1, hydroxyl group equivalent 105 g / eq. Manufactured by Meiwa Kasei)

  Curing accelerator: Triphenylphosphine (manufactured by Hokuko Chemical)

Examples 25 to 40 and Comparative Examples 3 and 4
Various components are blended in the proportions (parts) shown in Table 2, kneaded with mixing rolls, tableted, prepared by resin molding by transfer molding, heated at 160 ° C. for 2 hours, and further heated at 180 ° C. for 8 hours. Hardened | cured material of the epoxy resin composition of invention and the resin composition for a comparison was obtained. The results of measuring the thermal conductivity of these cured products are shown in Table 2.

Inorganic filler 1: spherical alumina (trade name: DAW-100, manufactured by Denki Kagaku Kogyo Co., Ltd., thermal conductivity 38 W / m · K)
Inorganic filler 2: Boron nitride (trade name: SGP, manufactured by Denki Kagaku Kogyo Co., Ltd., thermal conductivity 60 W / m · K)

Example 41
100 parts of the epoxy resin mixture 1 obtained in Example 1 was dissolved in 1000 parts of dimethylformamide at 70 ° C. and then returned to room temperature. In 48 parts of dimethylformamide, 20 parts of 1,5-naphthalenediamine (manufactured by Tokyo Chemical Industry, amine equivalent: 40 g / eq.) As a curing agent was dissolved at 70 ° C. and then returned to room temperature. The above epoxy resin solution and the curing agent solution are mixed and stirred with a stirring blade type homomixer to make a uniform varnish, and further an inorganic filler (trade name: SGP, manufactured by Denki Kagaku Kogyo Co., Ltd., thermal conductivity 60 W / m · K) 228 parts (50 parts by volume with respect to 100 parts by volume of resin solids) and 100 parts of dimethylformamide were added and mixed and stirred to prepare the epoxy resin composition of the present invention.
The varnish of this epoxy resin composition was impregnated into a 0.2 mm thick glass fiber woven fabric (trade name: 7628 / AS890AW, manufactured by Asahi Schwer) and dried by heating to obtain a prepreg. After the four prepregs and the copper foils arranged on both sides thereof were superposed, they were integrated by heating and pressing for 90 minutes under the conditions of a temperature of 175 ° C. and a pressure of 4 MPa to obtain a laminate having a thickness of 0.8 mm. The thermal conductivity of this laminate was measured and found to be 4.1 W / m · K.

Example 42
Same as Example 21 except that the epoxy resin mixture 1 in Example 41 was changed to 100 parts of the epoxy resin mixture 3, the amount of 1,5-naphthalenediamine was changed to 17 parts, and the amount of the inorganic filler was changed to 222 parts. A laminate was obtained by the following operation procedure. The heat conductivity of this laminate was measured and found to be 4.6 W / m · K.

Example 43
Same as Example 21 except that the epoxy resin mixture 1 in Example 41 was changed to 100 parts of the epoxy resin mixture 5, the amount of 1,5-naphthalenediamine was changed to 20 parts, and the amount of the inorganic filler was changed to 228 parts. A laminate was obtained by the following operation procedure. The thermal conductivity of this laminate was measured and found to be 4.1 W / m · K.

Example 44
Same as Example 21 except that the epoxy resin mixture 1 in Example 41 was changed to 100 parts of the epoxy resin mixture 7, the amount of 1,5-naphthalenediamine was changed to 16 parts, and the amount of the inorganic filler was changed to 222 parts. A laminate was obtained by the following operation procedure. The heat conductivity of this laminate was measured and found to be 4.5 W / m · K.

Comparative Example 5
Except that the epoxy resin mixture 1 in Example 41 was changed to 100 parts of epoxy resin 10 (YL-6121H), the amount of 1,5-naphthalenediamine was changed to 23 parts, and the amount of inorganic filler was changed to 234 parts. A laminate was obtained by the same operation procedure as in Example 21. The heat conductivity of this laminate was measured and found to be 3.6 W / m · K.

From the above results, it was confirmed that the cured product of the epoxy resin composition containing the epoxy resin mixture of the present invention has excellent thermal conductivity. Therefore, the epoxy resin of the present invention is extremely useful when used for insulating materials for electric / electronic parts, laminated boards (printed wiring boards, etc.) and the like.

  The cured product of the epoxy resin composition of the present invention has excellent thermal conductivity and superior solvent solubility as compared with a cured product of a conventional epoxy resin. Therefore, it is extremely useful for a wide range of applications such as an electric / electronic material, a molding material, a casting material, a laminated material, a paint, an adhesive, a resist, and an optical material as a sealing material and a prepreg.

Claims (9)

Following formula (1)-(5)

(In Formula (1), each R ₁ is independently present and is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a hydroxyl group, a nitro group, or an alkoxy having 1 to 10 carbon atoms. Represents one of the groups, l represents the number of R ₁ , and is an integer of 1 to 4)

(In Formula (2), each R ₂ is independently present, and is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkylcarbonyl group having 1 to 15 carbon atoms, or a carbon number. It represents any of 2-10 alkyl ester groups, C1-C10 alkoxy groups, morpholinylcarbonyl groups, phthalimide groups, piperonyl groups or hydroxyl groups.)

(In Formula (3), each R ₃ is independently present and is a hydrogen atom, an alkylcarbonyl group having 0 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or a carbon number. Represents an alkyl ester group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms or a hydroxyl group, n represents the number of carbon atoms, and represents an integer of 0, 1 or 2. m represents the number of R ₃ . And satisfies the relationship 1 ≦ m ≦ n + 2.)

(In the formula (4), _{R 4} are present each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, any of an alkoxy group or a hydroxyl group having 1 to 10 carbon atoms Represents.)

(In the formula (5), _{R 5} is present independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, 1 to 4 carbon atoms Represents an alkyl ester group of 10 to 10 or a hydroxyl group, and m is an integer of 1 to 10.)
One or more of the compounds represented by:
Following formula (6)

(In formula (6), each R ₆ is independently present and is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a hydroxyl group, a nitro group, a formyl group, an allyl group, or carbon. Represents one of the alkoxy groups of formula 1 to 10. k represents the number of R ₆ and is an integer of 1 to 4.) The phenol compound (a) and epihalohydrin obtained by the reaction with the compound represented by It contains an epoxy resin (A) obtained by reaction, and further has the following formula (7)

(In formula (7), R ₇ , X and Y are independently present, and represent any one of a hydrogen atom, an alkyl or aryl group having 1 to 10 carbon atoms, a hydroxyl group, or an alkoxy group having 1 to 10 carbon atoms. K represents the number of R ₇ and represents an integer of 1 to 4. The epoxy resin (B) and / or the formula (8) obtained by reacting an epihalohydrin with the phenol compound (b) represented by

(In Formula (8), R < ₈ > and A exist independently, R < ₈ > is any of a hydrogen atom, a C1-C10 alkyl group or aryl group, a hydroxyl group, or a C1-C10 alkoxy group. L represents the number of R ₈ and represents an integer of 1 to 4. A represents a direct bond or an alkylidene group having 5 to 15 carbon atoms having a cyclo ring.) an epoxy resin (C) obtained by reacting c) with an epihalohydrin,
Epoxy resin mixture containing An epoxy resin mixture obtained by reacting an epihalohydrin with a phenol compound mixture containing the phenol compound (a) according to claim 1 and further containing the phenol compound (b) and / or the phenol compound (c). Of the mixture of the phenol compounds (a) to (c) described in (1) before the reaction with the epihalohydrin, the sum of the proportions of the phenol compound (b) and the phenol compound (c) is 1 to 30% by mass. The epoxy resin mixture according to claim 2, obtained by reacting a mixture of phenol compounds with epihalohydrin. An epoxy resin composition comprising the epoxy resin mixture according to any one of claims 1 to 3 and a curing agent. The epoxy resin composition which contains the phenolic compound (a) as a hardening | curing agent among the epoxy resin compositions of Claim 4. The epoxy resin composition according to any one of claims 4 and 5, comprising an inorganic filler having a thermal conductivity of 20 W / m · K or more. The epoxy resin composition according to any one of claims 4 to 6, which is used for semiconductor sealing applications. A prepreg comprising the epoxy resin composition according to any one of claims 4 to 6 and a sheet-like fiber base material. Hardened | cured material formed by hardening | curing the epoxy resin composition as described in any one of Claims 4-7, or the prepreg of Claim 8.