JPH11302360A - Epoxy resin composition and cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition that has excellent blocking resistance and storage stability as well as high moldability, high moisture absorption, high resistance to heat and high adhesion between different kinds of materials and gives cured products with electric insulation. SOLUTION: This epoxy resin composition is prepared by melt-mixing or solution-mixing homogeneously 100 pts.wt. of an o-cresol type novolak type epoxy resin that is solid at room temperature and 5-100 pts.wt. of an aromatic oligomer that is prepared by polymerizing monomers mainly comprising indanes and is solid at room temperature. In another embodiment, an aromatic oligomer prepared by polymerizing o-cresol novolak type epoxy resin (OCNE), a phenolic curing agent, and a monomer mainly comprising indanes and >=75 wt.% of inorganic filler are used to produce an epoxy that is solid at room temperature. In these epoxy resin composition, the proportion of the aromatic oligomer is 5-100 pts.wt. to 100 pts.wt. of OCNE and the OCNE and the aromatic oligomers are preliminarily mixed homogeneously. The epoxy resin cured product is produced by curing the epoxy resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a cured product which is excellent in blocking resistance and storage stability, has excellent moldability, low moisture absorption, high heat resistance, excellent adhesion to dissimilar materials, and excellent electrical insulation. The present invention relates to an epoxy resin composition useful for encapsulation of electric and electronic parts to give a product, a circuit board material, and the like, and a cured product thereof.

[0002]

2. Description of the Related Art Conventionally, epoxy resins have been industrially used for a wide range of applications, but their required performance has been increasingly sophisticated in recent years. For example, semiconductor encapsulation materials are a typical field of resin compositions containing an epoxy resin as a main component, but with the improvement in the degree of integration of semiconductor elements, package sizes have become larger and thinner. The shift to surface mounting is progressing, and the development of a material having excellent solder heat resistance is desired. Influential methods for improving solder heat resistance include lowering the water absorption and improving the adhesion at the interface between different materials such as lead frames and chips.

[0003] In order to reduce the water absorption, the filling rate of the inorganic filler is increased, and a low-viscosity epoxy resin is desired. From these backgrounds, an epoxy resin for a semiconductor encapsulant using a bifunctional epoxy resin such as a biphenyl-based epoxy resin (Japanese Patent Publication No. 4-73565) and a bisphenol F-type epoxy resin (Japanese Patent Application Laid-Open No. 6-345850). Compositions have been proposed. These epoxy resins are excellent in low viscosity, high filler filling rate, and improved fluidity, but are inferior in handling properties such as compound blocking resistance and storage stability, and due to bifunctionality. It is difficult to increase the crosslink density, the hardness and the glass transition point of the cured product are reduced, and the moldability and heat resistance are reduced.

As epoxy resins having excellent moldability and heat resistance, polyfunctional o-cresol novolak type epoxy resins have been widely used, but they have a disadvantage of high viscosity and have a high filler filling rate. Had limitations. Therefore, the lowering of the molecular weight of the o-cresol novolak type epoxy resin has been studied, and a resin having a melt viscosity of 150 ° C. and a poise of 1 poise or less has been proposed. There is a problem that gets worse. In addition, as a material having low viscosity and improved blocking resistance, a material having a reduced bifunctional component and a high molecular weight material and a sharp molecular weight distribution has been proposed, but the adhesiveness is reduced. There was a problem.

As described above, various types of epoxy resins having a novel structure have been studied from the side of the epoxy resin serving as the main component, but the improvement of the main component alone results in a decrease in heat resistance and an improvement in adhesion due to low moisture absorption. It was difficult to balance the physical properties, such as a decrease in curability due to the above.

[0006] From such a background, an epoxy resin modifier has been studied. As one example, an indene maron resin has been conventionally known, and is disclosed in JP-A-1-24982.
No. 4 discloses that a coumarone-indene-styrene copolymer resin is applied to a semiconductor encapsulant, but the adhesiveness and fluidity are insufficient. Also, JP-A-6-107
Japanese Patent Application Publication No. 905 discloses that an indene-based resin having an increased indene content is applied to electronic material applications, but all oligomers having a high indene content have a high softening point, and are applied to semiconductor encapsulants. In such a case, it is difficult to increase the filling of the filler, and there is a problem that the fluidity during molding is reduced.

[0007]

Accordingly, an object of the present invention is to provide not only excellent blocking resistance and storage stability, but also excellent moldability, low moisture absorption, high heat resistance, and high adhesion to different materials. Another object of the present invention is to provide an epoxy resin composition which gives a cured product having excellent electrical insulation properties, and a cured product thereof.

[0008]

Means for Solving the Problems The present inventors have combined an o-cresol novolak type epoxy resin with a specific aromatic oligomer and uniformly mixed both components before preparing an epoxy resin composition. As a result, it has been found that excellent moldability, high heat resistance, low water absorption and high adhesion are exhibited while maintaining excellent solid handling properties and storage stability, thereby achieving the present invention.

That is, the present invention relates to 100 parts by weight of an o-cresol novolak type epoxy resin which is a solid at room temperature.
An epoxy resin composition obtained by uniformly mixing 5 to 100 parts by weight of a room temperature solid aromatic oligomer obtained by polymerizing a monomer mainly containing indenes by a melt mixing method or a solution mixing method. Further, the present invention mainly comprises an o-cresol novolak type epoxy resin, a phenolic curing agent, an aromatic oligomer obtained by polymerizing a monomer containing indene as a main component, and 75% by weight or more of an inorganic filler. In a room temperature solid epoxy resin composition, o-
The ratio of the aromatic oligomer to 100 parts by weight of the cresol novolak type epoxy resin is 5 to 100 parts by weight, and the o-cresol novolak type epoxy resin and the aromatic oligomer are uniformly premixed by a melt mixing method or a solution mixing method. An epoxy resin composition for sealing electronic parts or a cured epoxy resin obtained by curing the same. Here, the aromatic oligomer preferably has a softening point of 70 to 150 ° C.

[0010] The o- used in the epoxy resin composition of the present invention.
Cresol novolak type epoxy resin (also called OCNE) is not particularly limited in its production method,
It is a solid at room temperature and has a softening point of 40-100 ° C, preferably 5
The temperature is preferably from 0 to 80 ° C. If it is lower than this, the blocking resistance of the epoxy resin composition decreases, and if it is higher than this, the fluidity during molding decreases and it becomes difficult to increase the filling rate of the filler.

The purity of OCNE, particularly the amount of hydrolyzable chlorine, is preferably small from the viewpoint of improving the reliability of the electronic parts to be sealed. Although not particularly limited, 1000 pp
m or less is preferable. In addition, the hydrolyzable chlorine referred to in the present invention refers to a value measured by the following method. That is, after dissolving 0.5 g of a sample in 30 ml of dioxane, 1N
-KOH, after the added boiled under reflux for 30 minutes 10 ml, cooled to room temperature, 80% aqueous acetone 100ml was added, a value obtained perform potentiometric titration with 0.002 N-AgNO ₃ solution.

The aromatic oligomer used as a modifier of the epoxy resin composition of the present invention is a solid at room temperature obtained by polymerizing a monomer containing indene as a main component. The excellent adhesion and moisture resistance, which are the effects of the present invention, largely depend on the content of the indene structure, and the higher the ratio of the indene structure, the better from the viewpoint of physical property balance.

The aromatic oligomer is obtained by subjecting a monomer containing indene or a monomer copolymerizable with indene to a method such as cation polymerization, anion polymerization, or radical polymerization. In general, cation polymerization is preferred. Examples of copolymerizable monomers include, for example, methylindenes, benzothiophenes, methylbenzothiophenes, benzofurans,
Methylbenzofurans, styrene, alkylstyrenes, α-methylstyrene, vinylnaphthalene, vinylbiphenyl, acenaphthylene, acrylic acid, acrylic esters, methacrylic acid, methacrylic esters, maleic anhydride, fumaric acid, divinylbenzene Kind,
Monomers having an unsaturated bond, such as diisopropenylbenzene, may be mentioned, but aromatic olefin monomers are preferred. These compounding ratio is 50% by weight or less of all monomers,
Advantageously 30% or less is preferred.

As a raw material for the polymerization of the aromatic oligomer, a raw material mainly composed of a fraction at 130 to 200 ° C. obtained by distilling coal tar or coke oven gas light oil, or a raw material oil produced during petroleum refining or petroleum cracking. A raw material oil containing indene obtained by distilling an aromatic oil can be used.

[0015] The cationic polymerization is usually carried out in the presence of an acidic catalyst. The acidic catalyst can be appropriately selected from well-known inorganic acids and organic acids, for example, hydrochloric acid, sulfuric acid,
Mineral acids such as phosphoric acid, formic acid, oxalic acid, trifluoroacetic acid,
Organic acids such as p-toluenesulfonic acid and methanesulfonic acid; Lewis acids such as zinc chloride, aluminum chloride, iron chloride and boron trifluoride; and solid acids such as activated clay, silica alumina and zeolite.

This polymerization is usually carried out at 10 to 250 ° C. for 1 to 2 times.
Performed for 0 hours. In addition, alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve, ethyl cellosolve, benzene, toluene, chlorobenzene, etc.
An aromatic compound such as dichlorobenzene can be used.

Further, phenols may be used as a polymerization terminator during the polymerization. Examples of phenols include phenols, alkylphenols such as cresols,
Examples thereof include dialkylphenols such as xylenol, naphthols, bisphenols such as bisphenol A and bisphenol F, and polyfunctional phenol compounds such as phenol novolak and phenol aralkyl resin. The addition amount of these phenol compounds is usually 20% by weight or less. If the amount is more than this, the heat resistance and the moisture resistance of the cured epoxy resin are reduced.

The aromatic oligomer used in the epoxy resin composition of the present invention has a softening point of 70 to 150 ° C., preferably 80 to 130 ° C. and a melt viscosity at 150 ° C. of 4
It is good to be 100 poise, preferably 6-80 poise. If the melt viscosity and the softening point are lower than the above, the effect of improving the blocking resistance is small, and if the melt viscosity and the softening point are higher than this, the fluidity during molding decreases. The molecular weight of this aromatic oligomer is about 400 to 2000 in number average molecular weight.

The aromatic oligomer is preferably a high-purity aromatic oligomer having a low ionic component content. In particular, those containing less alkali metal ions such as sodium and potassium and less halogen ions such as chloride ion and bromide ion are preferable, and the content of the alkali metal ion and the halogen ion is 30 ppm or less, preferably 10 ppm or less.

The epoxy resin composition of the present invention contains OCN
There are a composition obtained by mixing E and an aromatic oligomer, and an epoxy resin composition for electronic component sealing obtained by further mixing a phenolic curing agent and an inorganic filler. In any of the compositions, the blending amount of the aromatic oligomer is OC
It is 5 to 100 parts by weight, preferably 10 to 40 parts by weight, based on 100 parts by weight of NE. If the amount is less than this, the fluidity at the time of molding is reduced, the effect of improving the blocking resistance is small, and the effect of reducing the water absorption of the cured product and the effect of improving the adhesion at the interface between different materials are small. On the other hand, if the amount is more than this, the hardness at the time of heat and the heat resistance of the cured product decrease, and the flame retardancy also decreases.

The composition obtained by mixing the OCNE and the aromatic oligomer is mixed at a temperature not lower than the melting point or the softening point of the composition by stirring or kneading, or the like. Is dissolved and uniformly mixed by stirring, kneading, or the like. Examples of the solvent used in the solution mixing method include alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve and ethyl cellosolve, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, benzene, toluene, xylene and chlorobenzene. And aromatic solvents such as dichlorobenzene. In preparing this composition, it is possible to mix an inorganic filler, another epoxy resin, and other additives (materials), but it is preferable to avoid mixing a curing agent.

The epoxy resin composition obtained by mixing the above-mentioned OCNE and an aromatic oligomer is a solid at room temperature,
Because of its excellent blocking resistance, it has excellent usability after long-term storage. Therefore, it can be used for various purposes using an epoxy resin in addition to a material for sealing electronic parts.

The epoxy resin composition for sealing electronic parts of the present invention can be obtained by mixing a phenolic curing agent and an inorganic filler with the epoxy resin composition prepared in advance. Here, if the respective components are simultaneously mixed without preparing the epoxy resin composition in advance, the blocking resistance of the obtained epoxy resin composition for sealing is not improved, and the heat resistance is lowered.

In the epoxy resin composition prepared in advance, if the mixing of both components is not uniform, the blocking resistance is not significantly improved, especially when combined with OCNE having a low softening point. The more uniform the mixture of both components, the greater the effect of improving the moldability and storage stability of this epoxy resin composition.

This epoxy resin composition for encapsulating electronic parts can be obtained by mixing the above-prepared epoxy resin composition, a phenolic curing agent and an inorganic filler, but is obtained by powder mixing. Is preferred. Here, as described above, the epoxy resin composition prepared in advance may optionally contain other components as long as the effects of the present invention are exerted. May be added, another epoxy resin or other additives (materials) may be added, and OCNE or a part of the aromatic oligomer may be newly mixed, but it is advantageous to mix a large amount. Absent.

The epoxy resin composition of the present invention contains OCN
In addition to E, a general epoxy resin having two or more epoxy groups in the molecule may be blended. Examples of such an epoxy resin include bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol,
Divalent phenols such as 4,4'-biphenol, 2,2'-biphenol, hydroquinone, resorcin, tris- (4-hydroxyphenyl) methane, 1,1,
Examples thereof include tri- or higher-valent phenols such as 2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak and o-cresol novolac, and glycidyl ether compounds derived from halogenated bisphenols such as tetrabromobisphenol A. . These epoxy resins may be used alone or in combination of two or more. The amount of these compounds may be within a range that does not impair the object of the present invention, but is usually preferably within 50% by weight of OCNE.

As the phenolic curing agent, a conventionally known epoxy resin curing agent such as phenol novolak can be used, and a polyhydric phenolic curing agent having an aralkyl-type structure can be used. A polyhydric phenol-based curing agent having an aralkyl-type structure can be produced by reacting a phenolic hydroxyl group-containing compound having an alkyl-substituted or unsubstituted benzene ring or naphthalene ring with a specific aromatic crosslinking agent.

Further, as the polyhydric phenol-based curing agent,
For example, bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4′-biphenol, 2,2′-biphenol, hydroquinone,
2 of resorcinol, catechol, naphthalene diols, etc.
Phenols, such as tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenol novolak, o-cresol novolak, naphthol novolak, and polyvinyl phenol. Trivalent or higher phenols,
Furthermore, phenols, naphthols or bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4′-biphenol, 2,
2'-biphenol, hydroquinone, resorcin, catechol, naphthalene diols and other divalent phenols and formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde, p-xylylene glycol, p-xylylene glycol dimethyl ether, divinylbenzene, divinylbenzene Examples include polyhydric phenolic compounds synthesized by reaction with a crosslinking agent such as isopropenylbenzene, dimethoxymethylbiphenyls, divinylbiphenyl, diisopropenylbiphenyls, and the like. These curing agents may be used alone or in combination of two or more.

The softening point of the phenolic curing agent is preferably from 40 to 150 ° C, more preferably from 50 to 120 ° C.
It is. If it is lower than this, there is a problem of blocking during storage, and if it is higher than this, there is a problem in kneadability and moldability in preparing the epoxy resin composition. The melt viscosity at 150 ° C. is preferably 20 poise or less, more preferably 5 poise or less. If it is higher than this, there are problems in kneadability and moldability during preparation of the epoxy resin composition.

The compounding ratio of the phenolic curing agent in the epoxy resin composition for encapsulation of the present invention may be within the range usually employed, but it is preferable that the phenolic hydroxyl group is 0.7 to 1 mol per epoxy group. It is preferable to mix them so as to be 1.2 mol.

Examples of the inorganic filler to be added to the sealing epoxy resin composition of the present invention include silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, silicon nitride, boron nitride, zirconia, fosterite, and steer. One or more of tight, spinel, mullite, titania and the like may be mentioned, and the form may be powder, spherical beads and the like. Of these, spherical fused silica is preferred from the viewpoint of increasing the packing of the inorganic filler. Usually, silica is used in combination with one having several types of particle size distribution. The range of the average particle size of the silica to be combined is preferably 0.5 to 100 μm.

The compounding ratio of the inorganic filler is 75% by weight or more, preferably 80% by weight of the whole epoxy resin composition for sealing.
% By weight or more. If less than this, the effect of improving the solder heat resistance is small.

The epoxy resin composition of the present invention may contain conventionally known curing accelerators such as amines, imidazoles, organic phosphines and Lewis acids. Specifically, 1,8-diazabicyclo (5,4,
0) tertiary amines such as undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol, 2-methylimidazole,
Imidazoles such as phenylimidazole, 2-phenyl-4-methylimidazole and 2-heptadecylimidazole; organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine and phenylphosphine; and tetraphenylphosphonium. Tetra-substituted phosphonium / tetra-substituted borate such as tetraphenyl borate, tetraphenyl phosphonium / ethyl triphenyl borate, tetrabutyl phosphonium / tetrabutyl borate, 2
And tetraphenylboron salts such as -ethyl-4-methylimidazole / tetraphenylborate and N-methylmorpholine / tetraphenylborate. The addition amount is usually 0.2 to 10 parts by weight based on 100 parts by weight of the epoxy resin.

Further, the epoxy resin composition of the present invention comprises:
Release agents such as carnauba wax and ester wax, coupling agents such as epoxy silane, amino silane, ureido silane, vinyl silane, alkyl silane, organic titanate, aluminum alcoholate, coloring agents such as carbon black, and difficulties such as antimony trioxide A low-stressing agent such as a combustion aid, silicone oil, or a lubricant such as a higher fatty acid or a metal salt of a higher fatty acid may be blended.

Generally, the above-mentioned raw materials are sufficiently mixed in a predetermined amount by a mixer or the like, kneaded by a mixing roll, an extruder, etc., cooled and pulverized to obtain an epoxy for sealing electronic parts. A resin composition can be prepared.

As a method for sealing an electronic component using the epoxy resin composition for sealing an electronic component, a low-pressure transfer molding method is the most common, but an injection molding method and a compression molding method are also used. It is possible. The epoxy resin cured product thus obtained and the electronic component sealed with the epoxy resin have excellent heat resistance and electrical insulation.

[0037]

The present invention will be described more specifically with reference to the following examples. Synthesis Example 1 70 g of indene, 25 g of styrene, and 5 g of phenol were dissolved in 250 g of toluene and heated to 115 ° C. Thereafter, 1 g of boron trifluoride dimethyl ether complex was added dropwise with stirring over 15 minutes. After the addition, the reaction was further performed for 3 hours. Thereafter, 2.4 g of calcium hydroxide was added for neutralization. The neutralized salt and excess calcium hydroxide were removed by filtration, and washing was repeated three times with 100 ml of ion-exchanged water. Then, toluene and unreacted monomer were removed by distillation under reduced pressure to obtain 89 g of an aromatic oligomer.
The softening point of the obtained resin (aromatic oligomer A) is 98 ° C.
And the melt viscosity at 150 ° C. was 8 poise.

Synthesis Example 2 The reaction was carried out in the same manner as in Reference Example 1 except that the reaction temperature was 90 ° C. to obtain 92 g of an aromatic oligomer. The obtained resin (aromatic oligomer B) had a softening point of 118 ° C. and a melt viscosity at 150 ° C. of 64 poise.

Synthesis Example 3 100 g of indene was dissolved in 250 g of toluene and reacted in the same manner as in Reference Example 1 to obtain 93 g of an aromatic oligomer. The softening point of the obtained resin (aromatic oligomer C) is 103 ° C.
And the melt viscosity at 150 ° C. was 10 poise.

Examples 1-4, Comparative Examples 1-2 Epoxy resin A (EOCN-1020-55, manufactured by Nippon Kayaku; epoxy equivalent: 200, hydrolyzable chlorine: 400 ppm, softening point: 55 ° C., OCNE type epoxy resin) 150 ° C melt viscosity 1 poise, dimer content 13.3%), epoxy resin B
(Nippon Kayaku, EOCN-1020-65; epoxy equivalent 200, hydrolyzable chlorine 400 ppm, softening point 65 ° C, 150 ° C melt viscosity 3 poise, dimer content 8.5%) was used. As the aromatic oligomer, the aromatic oligomers A to C of Synthesis Examples 1 to 3 were used.

An epoxy resin composition was prepared by melting and mixing an epoxy resin and an aromatic oligomer in the proportions (parts by weight) shown in Table 1 at 150 ° C. for 30 minutes. Table 1 shows the physical properties of the epoxy resin composition and the results of the blocking test. In addition,
The result of the blocking test was 2 m of the epoxy resin composition.
Using m-pass powder, the blocking ratio after standing at 20 ° C. for 6 hours was expressed in terms of% by weight. The softening point of the epoxy resin is a value measured using glycerin as a heat medium,
The melt viscosity is a value measured using Reomat 115 manufactured by Contrabass.

Examples 5 to 8 and Comparative Examples 3 to 8 Epoxy resin compositions or epoxy resins A to B of Examples 1 to 4 and aromatic oligomers A to
C, phenol novolak having a softening point of 80 ° C. as a curing agent (curing agent A: manufactured by Gunei Chemical Co., PSM-4261; OH equivalent: 103;
Novolak type brominated epoxy as a flame retardant (brominated epoxy A: Nippon Kayaku, BREN-S; epoxy equivalent 284, hydrolyzable chlorine 600 ppm, softening point 8)
4 ° C.), spherical silica (silica A: average particle size, 18 μm) as an inorganic filler, triphenylphosphine as a curing accelerator, and additives shown in Table 2, and powdered in the formulation (parts by weight) shown in Table 2. After mixing, the mixture was kneaded with a heating roll to prepare an epoxy resin composition for sealing.

175 ° C. using this epoxy resin composition
, And post-cured at 175 ° C. for 12 hours to obtain a cured product test piece, which was then subjected to various physical property measurements. The glass transition point was determined by a thermomechanical measuring device at a temperature rising rate of 7 ° C./min. The bending test is a high temperature bending strength at 240 ° C,
The flexural modulus was determined by a three-point bending method. Adhesion strength is 25mm x 12.5mm x 0.5 between two copper or iron plates
mm at 175 ° C using a compression molding machine.
After post-curing at 75 ° C. for 12 hours, the tensile shear strength was evaluated by obtaining the tensile shear strength. The water absorption was measured when a disk having a diameter of 50 mm and a thickness of 3 mm was molded using the epoxy resin composition and post-cured to absorb moisture at 85 ° C. and 85% RH for 100 hours. The rate is QFP-80 pin (14 mm x 20 mm x 2.5
mm, 194 alloy), and after post cure, 85
After absorbing moisture for a predetermined period of time at 85 ° C. and 85% RH, the package was immersed in a solder bath at 260 ° C. for 10 seconds, and the state of the package was observed and determined. Table 3 summarizes the results.

The results of the blocking test were determined by using a 1 mm pass powder of the epoxy resin composition at 25 ° C.
The blocking ratio after standing for 4 hours was represented by% by weight. The storage stability of the epoxy resin composition was measured at 25 ° C., 1
It was represented by the residual spiral flow rate after standing for a week.

[0045]

[Table 1]

[0046]

[Table 2]

[0047]

[Table 3]

[0048]

EFFECTS OF THE INVENTION The epoxy resin composition of the present invention has improved blocking resistance, excellent handling workability, and excellent low moisture absorption, high heat resistance, and high adhesion to different materials. It gives a cured product and can be suitably used as a sealing material for electronic / electric parts.

Continuation of the front page (51) Int.Cl. ⁶ Identification code FI H01L 23/29 H01L 23/30 R 23/31 (72) Inventor Katsumi Hotta 46, Nakahara-San, Ohara Nakata, Tobata-ku, Kitakyushu-shi, Fukuoka Prefecture 80 Nippon Steel Chemical Co., Ltd.

Claims (4)

[Claims] 1. A room temperature solid o-cresol novolac type epoxy resin is mixed with 100 to 100 parts by weight of a room temperature solid aromatic oligomer obtained by polymerizing a monomer containing indene as a main component by a melt mixing method. Or an epoxy resin composition obtained by uniformly mixing by a solution mixing method. 2. Room temperature containing o-cresol novolak type epoxy resin, phenolic curing agent, aromatic oligomer obtained by polymerizing monomers containing indene as a main component, and 75% by weight or more of inorganic filler as main components. In the solid epoxy resin composition, the ratio of the aromatic oligomer to 100 parts by weight of the o-cresol novolak type epoxy resin is 5 to 100 parts by weight, and the o-cresol novolak type epoxy resin and the aromatic oligomer are melt-mixed or An epoxy resin composition for encapsulating electronic components, which is premixed uniformly by a solution mixing method. 3. The softening point of the aromatic oligomer is from 70 to 1
The epoxy resin composition for sealing electronic parts according to claim 1, wherein the temperature is 50 ° C. 4. 4. An epoxy resin cured product obtained by curing the epoxy resin composition according to claim 1.