JP2012121962A - Epoxy resin composition, prepreg, and cured product of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin composition the cured product of which has high thermal conductivity and excellent heat resistance, by combining a specific resin containing a mesogenic group with a nitride-based inorganic filler such as boron nitride, aluminum nitride or silicon nitride having high thermal conductivity.SOLUTION: The epoxy resin composition contains an epoxy resin (A) which is obtained by reacting a phenol resin obtained by the reaction between a specific compound and hydroxybenzaldehydes, with an epihalohydrin, and an amine-based compound (B) having at least two amino groups as a curing agent.

Description

  The present invention relates to a novel epoxy resin composition and a prepreg obtained using the epoxy resin composition. Moreover, this invention relates to the hardened | cured material formed by hardening | curing the said epoxy resin composition or prepreg.

  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. Progressing. However, high-density mounting and high-density wiring increase the heat generated from the inside of the semiconductor element and the printed wiring board, and may cause malfunction of the devices. 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, Patent Document 1 reports a method of introducing a mesogenic group into an epoxy resin structure. This document describes an epoxy resin having a biphenyl skeleton as an epoxy resin having a mesogenic group. 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.
Patent Documents 2 to 4 describe examples using an epoxy resin having a biphenyl skeleton, and 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.

  Patent Documents 5 and 6 describe specific epoxy resins for improving low viscosity, low moisture absorption, and adhesion, but depending on the curing agent used in combination with the epoxy resin, thermal conductivity and heat resistance are good or bad. Therefore, the prior art has not proposed an epoxy resin composition having sufficiently high thermal conductivity and heat resistance, and development of an epoxy resin composition having such characteristics has been desired.

JP-A-11-323162 Japanese Patent Laid-Open No. 2004-2573 JP 2006-63315 A JP 2003-137971 A Japanese Patent Laid-Open No. 09-1003000 U.S. Pat. No. 3,937,685

  The present invention has been made as a result of studies to solve such problems, and provides an epoxy resin composition whose cured product has high thermal conductivity and excellent heat resistance.

（式（１）中、Ｒ_１はそれぞれ独立して存在し、水素原子、炭素数１〜１０の直鎖、分岐あるいは環状のアルキル基、炭素数１〜１０のアリール基、水酸基、又は、炭素数１〜１０の直鎖、分岐あるいは環状のアルコキシ基のいずれかを表す。ｎは炭素数を表し、０、１、２のいずれかの整数を表す。ｍはＲ_１の数を表し、１≦ｍ≦ｎ＋２の関係を満たす。）
で表される化合物とヒドロキシベンズアルデヒド類との反応によって得られるフェノール樹脂とエピハロヒドリンを反応させて得られる全ハロゲン量が、１６００ｐｐｍ以下である下記式（２）で表せられるエポキシ樹脂（Ａ）

（式（２）中、Ｒ_１はそれぞれ独立して存在し、水素原子、炭素数１〜１０の直鎖、分岐あるいは環状のアルキル基、炭素数１〜１０のアリール基、水酸基、又は、炭素数１〜１０の直鎖、分岐あるいは環状のアルコキシ基のいずれかを表し、Ｇはグリシドキシ基を表す。ｎは炭素数を表し、０、１、２のいずれかの整数を表す。ｍはＲ_１の数を表し、１≦ｍ≦ｎ＋２の関係を満たす。）、硬化剤としてアミノ基を少なくとも２つ有するアミン系化合物（Ｂ）を含有してなるエポキシ樹脂組成物、
（２）
前項（１）記載のエポキシ樹脂（Ａ）が、下記式（３）である前項（１）に記載のエポキシ樹脂組成物、

（式（３）中、Ｒ_１はそれぞれ独立して存在し、水素原子、炭素数１〜１０の直鎖、分岐あるいは環状のアルキル基、炭素数１〜１０のアリール基、水酸基、又は、炭素数１〜１０の直鎖、分岐あるいは環状のアルコキシ基のいずれかを表し、Ｇはグリシドキシ基を表す。ｎは炭素数を表し、０、１、２のいずれかの整数を表す。ｍはＲ_１の数を表し、１≦ｍ≦ｎ＋２の関係を満たす。）

（３）
アミノ基を少なくとも２つ有するアミン系化合物（Ｂ）がジアミノジフェニルメタン、ジアミノジフェニルスルホン、ナフタレンジアミンからなる群から選択される１種以上の化合物である（１）または（２）のいずれか一項に記載のエポキシ樹脂組成物、
（４）
熱伝導率が２０Ｗ／ｍ・Ｋ以上の無機充填材（Ｃ）を含有してなる（１）〜（３）のいずれか一項に記載のエポキシ樹脂組成物、
（５）
半導体封止用途に用いられる前項（１）〜（４）のいずれか一項に記載のエポキシ樹脂組成物、
（６）
前項（１）〜（４）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、
（７）
前項（１）〜（４）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（６）に記載のプリプレグを硬化してなる硬化物、 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)
Following formula (1)

(In Formula (1), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. Represents any of linear, branched or cyclic alkoxy groups of 1 to 10. n represents the number of carbon atoms and represents an integer of 0, 1 or 2. m represents the number of R ₁ ; ≦ m ≦ n + 2 is satisfied.)
An epoxy resin (A) represented by the following formula (2) in which the total halogen content obtained by reacting a phenol resin obtained by the reaction of a compound represented by formula (II) with hydroxybenzaldehyde and epihalohydrin is 1600 ppm or less.

(In Formula (2), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. It represents any of linear, branched or cyclic alkoxy groups of 1 to 10, G represents a glycidoxy group, n represents a carbon number, and represents an integer of 0, 1 or 2. m is R. represents the number of _1, satisfy 1 ≦ m ≦ n + 2 relationship.), epoxy resin composition comprising an amine compound having at least two amino groups as curing agent (B),
(2)
The epoxy resin composition according to item (1), wherein the epoxy resin (A) described in item (1) is represented by the following formula (3):

(In Formula (3), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. It represents any of linear, branched or cyclic alkoxy groups of 1 to 10, G represents a glycidoxy group, n represents a carbon number, and represents an integer of 0, 1 or 2. m is R. _Represents the number of 1 and satisfies the relationship 1 ≦ m ≦ n + 2.)

(3)
The amine compound (B) having at least two amino groups is one or more compounds selected from the group consisting of diaminodiphenylmethane, diaminodiphenylsulfone, and naphthalenediamine (1) or (2) The epoxy resin composition according to the description,
(4)
The epoxy resin composition according to any one of (1) to (3), comprising an inorganic filler (C) having a thermal conductivity of 20 W / m · K or more,
(5)
The epoxy resin composition according to any one of (1) to (4), which is used for semiconductor sealing applications,
(6)
A prepreg comprising the epoxy resin composition according to any one of (1) to (4) and a sheet-like fiber base material,
(7)
A cured product obtained by curing the epoxy resin composition according to any one of (1) to (4) or the prepreg according to (6);

Here, in the formula (1), examples of the alkyl group include alkyl groups having 1 to 10 carbon atoms such as a methyl group, an ethyl group, and a propyl group, and these alkyl groups may be linear or branched. It may be a shape.
Examples of the aryl group include aryl groups having 6 to 10 carbon atoms such as a phenyl group, a tolyl group, a xylyl group, and a naphthyl group, and these aryl groups may have a substituent such as the alkyl group.
Examples of the alkoxy group include C1-C10 alkoxy groups such as a methoxy group, an ethoxy group, a propoxy group, and a ketal group, and may be linear or branched.
About.

  The epoxy resin composition of the present invention is used for semiconductor encapsulating materials, various composite materials including prepregs, adhesives, paints, etc., because the cured product is particularly excellent in heat conduction and has high heat resistance. Useful when you want.

  The epoxy resin composition of the present invention comprises an epoxy resin (A) described in formula (2), an amine compound (B) having at least two amino groups, and an inorganic filler (C) having a thermal conductivity of 20 W / m · K or more. ) Containing an epoxy resin composition.

The epoxy resin (A) contained in the epoxy resin composition of the present invention will be described.
First, the phenol resin having a mesogenic group used in the present invention will be described.
The epoxy resin according to the present invention is obtained by further reacting an epihalohydrin with a phenol resin (hereinafter referred to as a phenol resin having a mesogenic group) obtained by reacting the compound represented by the formula (1) with hydroxybenzaldehydes. The resulting epoxy resin.
Examples of the compound represented by the formula (1) used in the reaction with hydroxybenzaldehydes to obtain the epoxy resin (A) used in the present invention include:
(A) a compound having a cyclopentanone skeleton such as cyclopentanone, 3-phenylcyclopentanone, 1,3-cyclopentanedione,
(B) Cyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 4-tert-butylcyclohexanone, 4-pentylcyclohexanone, 3-phenylcyclohexanone, 4-phenylcyclohexanone, 3,3-dimethylcyclohexanone, 3 1,4-dimethylcyclohexanone, 3,5-dimethylcyclohexanone, 4,4-dimethylcyclohexanone, 3,3,5-trimethylcyclohexanone, cyclohexanone skeleton having phenyl group, alkyl group or ester bond such as ethyl 4-cyclohexanone carboxylate A compound having,
(C) a ketal structure such as 1,4-cyclohexanedione monoethylene ketal, bicyclohexane-4,4′-dione monoethylene ketal, 1,4-cyclohexanedione mono-2,2-dimethyltrimethylene ketal and a cyclohexanone skeleton; A compound having,
(D) cyclohexanedione structures such as 1,3-cyclohexanedione, 1,4-cyclohexanedione, 5-methyl-1,3-cyclohexanedione, dimedone, dimethyl 1,4-cyclohexanedione-2,5-dicarboxylate, etc. A compound having,
(E) a compound having two cyclohexanone skeletons such as 4,4′-bicyclohexanone and 2,2-bis (4-oxocyclohexyl) propane;
(F) a compound having a cycloheptanone skeleton such as cycloheptanone,
Etc.
In this case, from the viewpoint of imparting high thermal conductivity to the cured product, R ₁ in the formula (1) is preferably a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, and particularly preferably a hydrogen atom. preferable.

  In order to obtain a phenol resin having a mesogenic group, examples of the hydroxybenzaldehyde used in the reaction with one or more compounds represented by the formula (1) include o-, m-, and p-hydroxybenzaldehyde. . These may use only 1 type or may use 2 or more types together. Of these, it is preferable to use p-hydroxybenzaldehyde alone because the cured product of the epoxy resin composition exhibits particularly high thermal conductivity.

The phenol resin having a mesogenic group is obtained by an aldol condensation reaction between one or more compounds represented by the formula (1) and hydroxybenzaldehyde under acidic conditions or basic conditions.
The hydroxybenzaldehyde is preferably used in an amount of 2.0 to 3.15 mol per 1 mol of the compound represented by the formula (1).

  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 hydroxy benzaldehydes, 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 hydroxy benzaldehydes, Preferably it is 0.2-2.0 mol.

  In the reaction for obtaining a phenol resin having a mesogenic group, a solvent may be used as necessary. The solvent that can be used is not particularly limited as long as it is not reactive with hydroxybenzaldehydes, such as ketones such as acetone and methyl ethyl ketone, but in terms of easily dissolving the raw hydroxybenzaldehydes, methanol, It is preferable to use alcohols such as ethanol and isopropyl alcohol as a solvent.

  The reaction temperature is usually 10 to 90 ° C, preferably 35 to 70 ° C. Although reaction time is 0.5 to 13 hours normally, since there is a difference in reactivity by 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 generated phenol resin having a mesogenic group may dissolve in water, so that it is precipitated as crystals under neutral to acidic conditions by adding hydrochloric acid or the like.

  In order to remove impurities, it is preferable to intervene a step of washing the crystals with water and then drying to obtain a phenol resin having a mesogenic group, and the phenol resin with less impurities can be obtained by this step.

（式（４）中、Ｒ_１はそれぞれ独立して存在し、水素原子、炭素数１〜１０の直鎖、分岐あるいは環状のアルキル基、炭素数１〜１０のアリール基、水酸基、又は、炭素数１〜１０の直鎖、分岐あるいは環状のアルコキシ基のいずれかを表す。ｎは炭素数を表し、０、１、２のいずれかの整数を表す。ｍはＲ_１の数を表し、１≦ｍ≦ｎ＋２の関係を満たす。）
で表せられる。
この場合において、エピハロヒドリンと反応させて得るエポキシ樹脂の硬化物の熱伝導性を高める観点から上記式（４）の化合物の中でも、下記式（５）の化合物が好ましい。

（式（５）中、Ｒ_１はそれぞれ独立して存在し、水素原子、炭素数１〜１０の直鎖、分岐あるいは環状のアルキル基、炭素数１〜１０のアリール基、水酸基、又は、炭素数１〜１０の直鎖、分岐あるいは環状のアルコキシ基のいずれかを表す。ｍはＲ_１の数を表し、１≦ｍ≦３の関係を満たす。） The phenol resin having a mesogenic group thus obtained has the following formula (4):

(In Formula (4), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. Represents any of linear, branched or cyclic alkoxy groups of 1 to 10. n represents the number of carbon atoms and represents an integer of 0, 1 or 2. m represents the number of R ₁ ; ≦ m ≦ n + 2 is satisfied.)
It can be expressed as
In this case, the compound of the following formula (5) is preferable among the compounds of the above formula (4) from the viewpoint of enhancing the thermal conductivity of the cured epoxy resin obtained by reacting with epihalohydrin.

(In Formula (5), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. This represents any of linear, branched or cyclic alkoxy groups of 1 to 10. m represents the number of R ₁ and satisfies the relationship 1 ≦ m ≦ 3.

Next, the epoxy resin used in the present invention will be described.
The epoxy resin used for this invention is obtained by making the phenol resin which has the mesogenic group obtained by the said method, and an epihalohydrin react, and epoxidizing. Moreover, you may use together phenol compounds other than the said phenol resin with the phenol resin which has a mesogenic group.
As the phenolic compound other than the phenolic resin that can be used in combination, any phenolic compound that is usually used as a raw material for epoxy resin can be used without particular limitation, but the effect of the present invention that the cured product has high thermal conductivity is impaired. Therefore, the amount of the phenol compound that can be used in combination is preferably as small as possible, and it is particularly preferable to use only the phenol resin having the mesogenic group.
The epoxy resin contained in the present invention is a phenol resin having a mesogenic group obtained by a reaction between a hydroxybenzaldehyde and a compound represented by the formula (1) because a cured product having a particularly high thermal conductivity is obtained. Can be used.

  In the reaction for obtaining the epoxy resin contained in the present invention, epichlorohydrin, α-methylepichlorohydrin, β-methylepichlorohydrin, epibromohydrin and the like can be used as the epihalohydrin, and epichlorohydrin which is easily available industrially is preferable. The usage-amount of epihalohydrin is 1-20 mol normally with respect to 1 mol of hydroxyl groups of the phenol resin which has a mesogenic group, Preferably it is 1.5-12 mol.

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 1 mol of the hydroxyl group of the phenol resin having a mesogenic group. -1.1 mol. Here, it is not preferable to use an alkali metal hydroxide as an aqueous solution because it is difficult to reduce the amount of residual halogen.
Here, as a method for adding the alkali metal as a solid, it is possible to divide it into several times to prevent a sudden increase in reaction temperature and the formation of impurities such as 1,3-halohydrin and halomethylene. To preferred.

  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 resin having a mesogenic group.

  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.

  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 4-20 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 hydrolyzable halogen contained in the obtained epoxy resin, the recovered epoxy resin is dissolved in a solvent such as toluene or methyl isobutyl ketone, and an alkali such as sodium hydroxide or potassium hydroxide is dissolved. You may react by adding the aqueous solution of a metal hydroxide. By performing such an operation, the ring closure can be ensured. 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 phenol resin which has a mesogenic group, 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.
By such an operation, the amount of halogen can be more effectively reduced.

After completion of the reaction, the produced salt is removed by filtration, washing with water, and the like, and the solvent is distilled off under heating and reduced pressure to obtain the epoxy resin of the present invention. Alternatively, the epoxy resin crystal may be collected by filtering the epoxy resin deposited as crystals after dissolving a salt generated in a large amount of water.
The residual halogen content of the epoxy resin contained in the present invention thus obtained is usually 1800 ppm or less, and preferably 1600 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.

  Moreover, the softening point of the epoxy resin which this invention contains is 50-120 degreeC normally, Preferably it is 50-80 degreeC.

（式（２）中、Ｒ_１はそれぞれ独立して存在し、水素原子、炭素数１〜１０の直鎖、分岐あるいは環状のアルキル基、炭素数１〜１０のアリール基、水酸基、又は、炭素数１〜１０の直鎖、分岐あるいは環状のアルコキシ基のいずれかを表し、Ｇはグリシドキシ基を表す。ｎは炭素数を表し、０、１、２のいずれかの整数を表す。ｍはＲ_１の数を表し、１≦ｍ≦ｎ＋２の関係を満たす。）
で表せられる。
また、本発明のエポキシ樹脂においては、硬化物の熱伝導性が高いエポキシ樹脂を得る観点から、上記エポキシ樹脂において上記式（２）が下記式（３）

（式（３）中、Ｒ_１はそれぞれ独立して存在し、水素原子、炭素数１〜１０の直鎖、分岐あるいは環状のアルキル基、炭素数１〜１０のアリール基、水酸基、又は、炭素数１〜１０の直鎖、分岐あるいは環状のアルコキシ基のいずれかを表し、Ｇはグリシドキシ基を表す。ｎは炭素数を表し、０、１、２のいずれかの整数を表す。ｍはＲ_１の数を表し、１≦ｍ≦ｎ＋２の関係を満たす。）
で表せられるエポキシ樹脂であることが特に好ましい。
さらに、上記（３）式においてｎ＝１であり、Ｒ_１が全て水素原子のものが特に好ましい。 The epoxy resin contained in the present invention obtained by the above method is usually represented by the following formula (2)

(In Formula (2), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. It represents any of linear, branched or cyclic alkoxy groups of 1 to 10, G represents a glycidoxy group, n represents a carbon number, and represents an integer of 0, 1 or 2. m is R. _Represents the number of 1 and satisfies the relationship 1 ≦ m ≦ n + 2.)
It can be expressed as
In the epoxy resin of the present invention, from the viewpoint of obtaining an epoxy resin having high thermal conductivity of the cured product, the above formula (2) in the above epoxy resin is represented by the following formula (3).

(In Formula (3), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. It represents any of linear, branched or cyclic alkoxy groups of 1 to 10, G represents a glycidoxy group, n represents a carbon number, and represents an integer of 0, 1 or 2. m is R. _Represents the number of 1 and satisfies the relationship 1 ≦ m ≦ n + 2.)
An epoxy resin represented by the formula is particularly preferred.
Furthermore, it is particularly preferable that n = 1 in the above formula (3) and R ₁ is all hydrogen atoms.

Next, the amine compound (B) having at least two amino groups will be described.
The amine compound having at least two amino groups used in the present invention is not particularly limited as long as it is an amine compound having at least two known amino groups, and specifically, diaminodiphenylmethane, naphthalenediamine, diaminodiphenylsulfone. An amine compound having an alicyclic structure such as an amine compound having three or more amino groups such as diethylenetriamine and triethylenetetramine, an isophoronediamine, and the like.
This is because the amine-based curing agent has a structure in which active hydrogen groups are adjacent to each other, whereby the epoxy resin is well arranged. In amines, hydrogen groups that react during thermosetting are arranged in parallel via nitrogen atoms, and in this case as well, polymerization is performed so that they are arranged in parallel.
Of these, amine compounds having two amino groups are preferred, amine compounds having an aromatic ring are more preferred, and diaminodiphenylmethane, naphthalenediamine, diaminodiphenyl are preferred from the viewpoint of obtaining a cured product having high thermal conductivity and heat resistance. Sulfone is particularly preferred.
When another curing agent is used in combination with the amine compound (B) having at least two amino groups used in the present invention, at least two amino groups in the total curing agent component in the epoxy resin composition of the present invention are used. The proportion of the amine compound is preferably 50% by weight or more, more preferably 60% by weight or more, and particularly preferably 80% by weight or more.
In the epoxy resin composition of the present invention, the content of the curing agent containing the amine compound (B) having at least two amino groups is preferably 0.5 to 2.0 equivalents relative to the epoxy equivalent of all epoxy resins, 0.8 to 1.2 equivalents are particularly preferred.

The inorganic filler (C) 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 heat of the inorganic filler itself. If the conductivity is too low, 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, Preferably it is 400-1000 mass parts, but is heat conduction. In order to increase the rate as much as possible, it is preferable to increase the amount of the inorganic filler as much as possible within a range that does not hinder the handling of the epoxy resin composition of the present invention in a specific application. These inorganic fillers may be used alone or in combination of two or more.

  Further, 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 20 W / m · K or less. However, in order to obtain a cured product having as high a thermal conductivity as possible, the use of a filler having a thermal conductivity of 20 W / m · K or less 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 and prepreg applications, it is 60 to 93 in the epoxy resin composition from the viewpoint of heat resistance, moisture resistance, mechanical properties, etc. of the cured product. It is preferable to use an inorganic filler having a thermal conductivity of 20 W / m · K or more in a proportion of mass%. 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.

  In the epoxy resin composition of the present invention, the epoxy resin (A) can be used alone or in combination with another epoxy resin (hereinafter referred to as “component (a)”).

Specific examples of the component (a) include bisphenols (bisphenol A, bisphenol F, bisphenol S, biphenol, bisphenol AD, bisphenol I, etc.) and phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol, naphthol, alkyl-substituted). Naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene and dihydroxynaphthalene) and various aldehydes (formaldehyde, acetaldehyde, alkylaldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, crotonaldehyde, cinnamaldehyde, etc.) Polycondensates of benzene and aromatic compounds such as xylene and formaldehyde Polycondensates with phenols, phenols and various diene compounds (dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.) Polycondensates, polycondensates of phenols and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, etc.), phenols and aromatic dimethanols (benzene dimethanol, biphenyl dimethanol, etc.) Polycondensates, polycondensates of phenols and aromatic dichloromethyls (such as α, α'-dichloroxylene and bischloromethylbiphenyl), phenols and aromatic bisalkoxymethyls (bi Polycondensates with smethoxymethylbenzene, bismethoxymethylbiphenyl, bisphenoxymethylbiphenyl, etc.), polycondensates of bisphenols and various aldehydes, and glycidyl ether epoxy resins and alicyclic epoxies obtained by glycidylation of alcohols, etc. Resins, glycidylamine epoxy resins, glycidyl ester epoxy resins, and the like can be mentioned, but are not limited thereto as long as they are usually used epoxy resins. These may be used alone or in combination of two or more.
When the component (a) is used in combination, the proportion of the epoxy resin (A) 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. The above is more preferable, and particularly preferable is 100% by mass (when the component (a) is not used in combination). However, when using an epoxy resin (A) as a modifier of an epoxy resin composition, it adds in the ratio used as 1-30 mass% in all the epoxy resins.

In the epoxy resin composition of the present invention, the amine compound (B) component which is a curing agent can be used alone or in combination with other curing agents.
Examples of other curing agents (hereinafter referred to as “component (b)”) contained in the epoxy resin composition of the present invention include acid anhydride compounds, amide compounds, phenol compounds, and the like. Specific examples of these components (b) are shown in the following (a) to (d).
(I) Acid anhydride compounds Phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methyl nadic anhydride, hexahydrophthalic anhydride and methylhexahydro Phthalic anhydride, etc. (b) Amide compounds Dicyandiamide, or polyamide resin synthesized from dimer of linolenic acid and ethylenediamine,

(C) Phenol compounds Polyphenols (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) Phenolic resins obtained by condensation with xybenzaldehyde, 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 (D) other imidazoles, BF 3 _- amine complex, guanidine derivatives

Among these components (b), catechol and aldehydes, ketones, dienes, substituted biphenyls or condensed phenyls are preferable. This is because these components have a structure in which active hydrogen groups are adjacent to each other, whereby the epoxy resin is well arranged. For example, in the case of a condensate with catechol, since the hydroxyl groups that react by thermosetting are in the ortho positions, they are polymerized so as to be arranged in parallel.
Component (b) may be used alone or in combination.
When the component (b) is used in combination, the proportion of the amine compound (B) component in the total curing agent component in the epoxy resin composition of the present invention is preferably 50% by mass or more, more preferably 60% by mass or more, and 80 More preferably, it is more than mass%.
In the epoxy resin composition of the present invention, the amount of the total curing agent containing the component (B) is preferably 0.5 to 2.0 equivalents relative to 1 equivalent of the epoxy groups of all epoxy resins, and 0.8 to 1 .2 equivalents are particularly preferred.
As the epoxy resin composition of the present invention, it is most preferable to use 100% by mass as an epoxy resin and 100% by mass as a curing agent.

  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. Formation of the cured product of the present invention includes, for example, an epoxy resin, a curing agent, an inorganic filler having a thermal conductivity of 20 W / m · K or more, and if necessary, a curing accelerator, a compounding agent, various thermosetting resins, and various heat After thoroughly mixing a plastic resin or the like with an extruder, kneader, or roll until it becomes uniform to obtain an epoxy resin composition, the epoxy resin composition is melt-cast, transfer molding, injection molding It can be carried out by molding by the method or compression molding method and then heating for 2 to 10 hours above its melting point. When the epoxy resin composition of the present invention is used for semiconductor sealing applications, the semiconductor element mounted on a lead frame or the like may be sealed by the above method.

Moreover, the epoxy resin composition of this invention can also be made into the varnish containing a solvent. The varnish includes, for example, a mixture containing an epoxy resin, a curing agent, an inorganic filler having a thermal conductivity of 20 W / m · K or more, and other components as necessary, 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, dipropylene glycol diethyl Glycol ethers such as ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, ethyl acetate, butyl acetate, methyl cellosolve acetate, ethyl cello Rub 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, hydrogenated petroleum It can be obtained by mixing with an organic solvent such as a petroleum solvent such as 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 sheet-like fiber base material such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber and paper, and then the solvent is removed by heating, and the varnish is half-finished. By setting it to a 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, melting point, and thermal conductivity were measured under the following conditions.
・ Melting point Seiko Instruments
Inc. EXSTAR6000 made
Measurement sample 2 mg to 5 mg Temperature rising rate 10 ° C./min.
Melt viscosity Melt viscosity in cone plate method at 150 ° C. Measuring instrument: cone plate (ICI) high temperature viscometer Softening point Measured by the method described in JIS K-7234, the unit is ° C.
-Total chlorine amount A value obtained by measuring the amount (mol) of chlorine liberated by adding a 1N-KOH propylene glycol solution to a butyl carbitol solution of a sample and refluxing for 10 minutes by a silver nitrate titration method and dividing by the weight of the sample.
-Epoxy equivalent Measured by the method described in JIS K-7236, the unit is g / eq. It is.
-Thermal conductivity It measures by the method based on ASTM E1530.
・ Glass transition temperature (DMA)
Using a TM-7000 manufactured by Vacuum Riko Co., Ltd., the temperature rising rate was 2 ° C / min. Measured under the conditions of

Synthesis Example 1
A flask equipped with a stirrer, a reflux condenser, and a stirrer was charged with 49 parts of cyclohexanone, 124 parts of p-hydroxybenzaldehyde and 250 parts of ethanol and dissolved. After adding 25 parts of 37% hydrochloric acid to this, the temperature was raised to 60 ° C., and after reacting at this temperature for 10 hours, the reaction solution was poured into 1000 parts of water for crystallization. The crystals were separated by filtration, washed twice with 800 parts of water, and then vacuum-dried to obtain 210 parts of phenol compound 1 as yellow crystals. The melting point of the obtained crystal was 289 ° C. by DSC measurement.

Synthesis Example 2
While purging a flask equipped with a stirrer, a reflux condenser, and a stirrer with nitrogen purge, add 153 parts of the phenol compound 1 obtained in Synthesis Example 1, 925 parts of epichlorohydrin, and 139 parts of methanol, and the mixture is stirred at 70 ° C. The temperature was raised to 43 parts, and 43 parts of flaky sodium hydroxide was added in portions over 90 minutes, and then the reaction was carried out for 90 minutes at 70 ° C. After completion of the reaction, washing with water was performed to remove the generated salt and the like, and then excess solvent such as epichlorohydrin was distilled off under reduced pressure at 160 ° C. using a rotary evaporator. After the distillation, it was dissolved again in methyl ethyl ketone at 75 ° C., 13 parts of 30% aqueous sodium hydroxide solution was added, and the reaction was carried out for 80 minutes while maintaining at 75 ° C. After completion of the reaction, the water layer was sufficiently washed until neutral, and then vacuum dried at 180 ° C. to obtain 199 parts of epoxy resin 1 of the present invention. The resulting epoxy resin had a softening point of 68 ° C., a melt viscosity of 0.06 Pa · s (150 ° C.), a total chlorine content of 1500 ppm, and an epoxy equivalent of 219 g / eq. Met.

Examples 1-3 and Comparative Examples 1-3
Various components were blended in the proportions (parts) shown in Table 1, and after kneading with a mixing roll and subsequent tableting, a resin molded body was prepared by transfer molding. Next, the resin molding was heated at 200 ° C. for 8 hours to obtain a cured product of the epoxy resin composition of the present invention and the comparative resin composition. The results of measuring the thermal conductivity of these cured products are shown in Table 1.

  Epoxy resin 2: Biphenyl type epoxy resin containing an equimolar amount of an epoxy resin represented by the following formulas (6) and (7) (trade name: YL-6121H manufactured by Japan Epoxy Resin, epoxy equivalent of 175 g / eq.)

Curing agent 1: 1,5-naphthalenediamine (manufactured by Tokyo Chemical Industry, amine equivalent 40 g / eq.)
Curing agent 2: 4,4′-diaminodiphenylmethane (manufactured by Tokyo Chemical Industry, amine equivalent 50 g / eq.)
Curing agent 3: 4,4′-diaminodiphenyl sulfone (manufactured by Tokyo Chemical Industry, amine equivalent 62 g / eq.)

  From the above results, it was confirmed that the cured product of the epoxy resin composition of the present invention had excellent thermal conductivity. Therefore, the cured product of the epoxy resin composition 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 reliability 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 (7)

Following formula (1)

(In Formula (1), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. Represents any of linear, branched or cyclic alkoxy groups of 1 to 10. n represents the number of carbon atoms and represents an integer of 0, 1 or 2. m represents the number of R ₁ ; ≦ m ≦ n + 2 is satisfied.)
An epoxy resin (A) represented by the following formula (2) in which the total halogen content obtained by reacting a phenol resin obtained by the reaction of a compound represented by formula (II) with hydroxybenzaldehyde and epihalohydrin is 1600 ppm or less.

(In Formula (2), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. It represents any of linear, branched or cyclic alkoxy groups of 1 to 10, G represents a glycidoxy group, n represents a carbon number, and represents an integer of 0, 1 or 2. m is R. ₁ represents the number of 1 and satisfies the relationship 1 ≦ m ≦ n + 2.) An epoxy resin composition comprising an amine compound (B) having at least two amino groups as a curing agent. The epoxy resin composition according to claim 1, wherein the epoxy resin (A) according to claim 1 is represented by the following formula (3).

(In Formula (3), each R ₁ is independently present and is a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, a hydroxyl group, or carbon. It represents any of linear, branched or cyclic alkoxy groups of 1 to 10, G represents a glycidoxy group, n represents a carbon number, and represents an integer of 0, 1 or 2. m is R. _Represents the number of 1 and satisfies the relationship 1 ≦ m ≦ n + 2.)
The amine compound (B) having at least two amino groups is at least one compound selected from the group consisting of diaminodiphenylmethane, diaminodiphenylsulfone, and naphthalenediamine. The epoxy resin composition as described. The epoxy resin composition according to any one of claims 1 to 3, comprising an inorganic filler (C) having a thermal conductivity of 20 W / m · K or more. The epoxy resin composition as described in any one of Claims 1-4 used for a semiconductor sealing use. A prepreg comprising the epoxy resin composition according to any one of claims 1 to 4 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 1-4, or the prepreg of Claim 6.