JPH04332721A - Epoxy resin composition and resin encapsulation type device - Google Patents

Abstract

PURPOSE:To provide an epoxy resin composition having an improved toughness of an inorganic filler-containing epoxy resin and its molding. CONSTITUTION:An epoxy resin composition mainly composed of an epoxy resin, an inorganic filler, a curing agent and a phenolic hydroxyl group- containing aramid-polybutadiene-acrylonitrile block copolymer.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic filler-reinforced composite material which uses an epoxy resin as a matrix material and has significantly improved toughness.

0002

[Prior Art] Epoxy resins have traditionally been used as adhesives, base materials for configuring electronic devices or electronic components such as laminates, and resins for sealing materials for coating transistors, ICs, etc. It has been. In particular, demand is increasing as a sealing material for ICs. Epoxy resin has excellent electrical properties, adhesive properties, thermal properties, cost, etc., and therefore has a very wide range of uses. However, epoxy resins are generally brittle and easily crack due to stress distortion, heat, or mechanical impact during curing or use. To deal with this problem, we can use curing agents with long-chain aliphatic groups or rubber-like properties, add compounds with elastomeric properties, add asphalt materials, plasticizers such as glycols, and add rubber elasticity to the epoxy compound itself. Efforts are being made to improve its toughness by introducing molecular groups that show
Koichi, Kobunshi 38(3), 200 (1989).

0003

[Problems to be solved by the invention] However, these substances are not sufficiently compatible with epoxy resin, the size of the sea-island structure formed by mixing is large, and sufficient composite properties cannot be obtained. Problems have arisen in that properties such as heat resistance and adhesiveness are impaired, and the cost is extremely high. In particular, encapsulation resins made of cured epoxy resin compositions used to encapsulate semiconductor and electronic components are not only required to have heat resistance to withstand soldering when mounted on printed circuit boards. In response to the recent trend toward thinner ICs, a strong sealing resin that is strong against bending and the like is required even if it is thin. The present invention has been made in view of these problems, and it is an object of the present invention to provide an inorganic filler-reinforced epoxy resin composition having an epoxy resin as a matrix and having improved toughness. Furthermore, by curing and molding these fiber-reinforced composite materials under suitable conditions, the present invention aims to provide cured molded products that are extremely useful in the fields of structural materials, electricity, electronic materials, and the like.

0004

[Means for Solving the Problems] As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that at least a phenolic hydroxyl group-containing aramidopolybutadiene-acrylonitrile block combination represented by the following general formula (I) has been developed. The present invention was completed based on the discovery that the objects of the present invention can be achieved by producing a filler-reinforced composite material composed of a polymer, an epoxy resin, a curing agent, and an inorganic filler. The present invention provides a reaction product (A) of a phenolic hydroxyl group-containing aramidopolybutadiene-acrylonitrile block copolymer represented by general formula (I) and an epoxy resin,
This is an epoxy resin composition containing an epoxy resin, a curing agent, and an inorganic filler.

[Chemical formula 2] (where x=an integer of 3 to 7, y=an integer of 1 to 4, y/(
x+y)=0.1 to 0.3, z=an integer of 5 to 15, m
= integer from 1 to 400, n = integer from 1 to 400, n/(m
+n) = 0.01 to 0.50, 1 = integer of 1 to 50, A
r1 and Ar3 are divalent aromatic groups, and Ar2 is a divalent aromatic group containing a phenolic hydroxyl group). In the present invention, phenolic hydroxyl group-containing aramid of formula (I)
The content of the polybutadiene-acrylonitrile block copolymer is 0.1 to 15% by weight based on the epoxy resin.
is preferred. The present invention is a resin-sealed semiconductor device further characterized in that a semiconductor chip is sealed with the resin composition.

That is, in the present invention, the above general formula (
The phenolic hydroxyl group-containing aramidopolybutadiene-acrylonitrile copolymer shown in I) promotes toughening of the epoxy resin, but this copolymer is molecularly dispersed uniformly in the epoxy resin to toughen the epoxy resin, and this molecular dispersion size It is assumed that the epoxy resin matrix with this inorganic filler spacing is a toughened continuum, and that the toughening of the inorganic filler-reinforced composite takes place efficiently. Ru. It is also believed that the phenolic compound promotes the toughening effect of this aramidopolybutadiene-acrylonitrile copolymer component in a more curing manner. The toughening effect of this phenolic hydroxyl group-containing aramidopolybutadiene-acrylonitrile block copolymer is achieved with a small amount of these copolymers added, so the excellent properties of the epoxy resin are not impaired. In addition, it has the great feature of improving its heat resistance, and it significantly improves inorganic filler-reinforced composite epoxy resin materials that use epoxy resin as a matrix.

Block copolymer (I) used in the present invention
) can be synthesized by the following method. That is, the general formula (I
) A divalent aromatic group having a phenolic hydroxyl group Ar
2 and an aromatic dicarboxylic acid having a divalent aromatic group Ar1 in the general formula (I) and having no phenolic hydroxyl group, an excess amount of the aromatic dicarboxylic acid having the general formula (I)
) in an organic solvent represented by N-methyl-2-pyrrolidone in the presence of a phosphite ester and a pyridine derivative. Heat and stir under an inert atmosphere such as nitrogen. As a result, a polybutadiene-acronitrile copolymer having carboxyl groups at both ends is added to the resulting polyaramid oligomer solution containing aminoaryl groups at both ends, and block copolymerization is carried out by polycondensation. Combined (I) is obtained. In addition, polybutadiene-acrylonitrile copolymer having carboxyl groups at both ends is available from Goodrich Co., Ltd.
rCTBN, and these can be used.

The aromatic dicarboxylic acids having a phenolic hydroxyl group include 4-hydroxyisophthalic acid,
5-hydroxyisophthalic acid, 2-hydroxyphthalic acid, and 2-hydroxyterephthalic acid can be used, and examples of the aromatic dicarboxylic acids that do not have a phenolic hydroxyl group include phthalic acid, isophthalic acid, terephthalic acid, 4,4
'-Biphenyldicarboxylic acid, 3,3'-methylene dibenzoic acid, 4,4'-methylene dibenzoic acid, 4,4'-oxydibenzoic acid, 4,4'-thiodibenzoic acid, 3,3'
-Carbonyl dibenzoic acid, 4,4'-carbonyl dibenzoic acid, 4,4'-carbonyl dibenzoic acid, 4,4'-sulfonyl dibenzoic acid, 1,4-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid Examples include, but are not limited to, acids, 2,6-naphthalene dicarboxylic acid, and the like. These aromatic dicarboxylic acids can be used alone or in combination.

Furthermore, examples of the aromatic diamine include m-phenylene diamine, p-phenylene diamine,
3,3'-oxydianiline, 3,4'-oxydianiline, 4,4'-oxydianiline, 3,3'-diaminobenzophenone, bis(4-aminophenyl)sulfone, bis(3-aminophenyl) ) Sulfone, bis(4-
aminophenyl) sulfide, 1,4-naphthalenediamine, 2,6-naphthalenediamine, 4,4'-bis(
4-phenoxy)diphenylsulfone, 4,4'-bis(3-phenoxy)diphenylsulfone, 2,2'-(
Examples include, but are not limited to, 4-aminophenyl)propane, bis(4-aminophenyl)methane, o-tolidine, and o-dianilidine. These aromatic diamines can also be used in combination.

[0009] The epoxy resin used in the epoxy resin composition of the present invention is not limited, but one having two or more epoxy groups in one molecule is preferred. Examples of such compounds include glycidyl ethers, glycidyl esters, glycidyl amines, linear aliphatic epoxies, and alicyclic epoxides. Examples of glycidyl ethers include glycidyl ether of bisphenol, polyglycidyl ether of phenol novalac,
Examples include glycidyl ether of alkylene glycol or polyalkylene glycol. As the glycidyl ether of bisphenol, bisphenol A
, bisphenol F, bisphenol AD, bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol AD,
Diglycidyl ethers of dihydric phenols such as tetramethylbisphenol S, tetrachlorobisphenol A, and tetrabromobisphenol A are used as polyglycidyl ethers of phenol novolaks, such as novolak resins such as phenol novolak, cresol novolac, and brominated phenol novolak. Examples of the polyglycidyl ether of alkylene glycol or the diglycidyl ether of polyalkylene glycol include diglycidyl ethers of glycols such as polyethylene glycol, polypropylene glycol, and butanediol.

[0010] Examples of the glycidyl esters include hexahydrophthalic acid glycidyl esters and dimer acid glycidyl esters, and examples of the glycidyl amines include triglycidylamino diphenylmethane, triglycidylaminophenol, and triglycidyl aminophenol. Examples include glycidyl isocyanurate. Further, examples of linear aliphatic epoxides include epoxidized polybutadiene and epoxidized soybean oil, and examples of alicyclic epoxides include 3,4-epoxy-6-methylcyclohexylmethylcarboxylate, 3, Examples include 4-epoxycyclohexylmethylcarboxylate. In the epoxy resin composition of the present invention, these epoxy resins can be used alone or in combination.

Examples of the curing agent used in the present invention include bis(4-aminophenyl)sulfone, bis(4-aminophenyl)methane, 1,5-diaminonaphthalene, p
-phenylenediamine, m-phenylenediamine, o-
Aromatic amine compounds such as phenylenediamine, 2,6-dichloro-1,4-benzenediamine, 1,3-(p-aminophenyl)propane, m-xylenediamine,
Aliphatic amines such as ethylenediamine, diethylenetriamine, tetraethylenepentamine, diethylaminopropylamine, hexamethylenediamine, menzendiamine, isophoronediamine, bis(4-amino-3-methyldicyclohexyl)methane, polymethylenediamine, polyetherdiamine, etc. -based compounds, polyaminoamide-based compounds, aliphatic acid anhydrides such as dodecylsuccinic anhydride, polyadipic anhydride, and polyazelaic anhydride, alicyclic acid anhydrides such as hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, etc. , aromatic acid anhydrides such as phthalic anhydride, trimellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bis trimellitate, glycerol tris trimellitate, dicyandiamide,
Basic active hydrogen compounds such as organic acid dihydrazides, imidazole compounds, Lewis acids and blessed acid salts,
Examples include, but are not limited to, polymercaptan compounds, phenolic resins, urea resins, melamine resins, isocyanate and blocked isocyanate compounds.

The reaction product used in the present invention is obtained by reacting the phenolic hydroxyl group-containing aramid-polybutadiene-acrylonitrile copolymer represented by the general formula (I) with an epoxy resin in an amide solvent. As the amide solvent, N,N-dimethylformamide, N
, N-dimethylacetamide, N-methyl-2-pyrrolidone, etc. are used. The amount of epoxy resin used is 1 to 20 times equivalent, preferably 5 to 15 times equivalent, relative to the block copolymer (I). The reaction temperature is 50°C or higher, preferably 70°C or higher.

[0013] The inorganic filler has a particle size of 0.1 to 10
Spherical or non-spherical fused silica of about 0 μm, crystalline silica, glass flakes, glass beads, glass balloons,
Talc, alumina, calcium silicate, calcium carbonate, barium sulfate, magnesia, silicon nitride, boron nitride, ferrite, rare earth cobalt, gold, silver, nickel, copper,
Commonly known materials such as lead, iron powder, iron oxide, metal powder such as iron sand, graphite, and carbon can be used. These contents are generally 10 to 8 for epoxy resin.
00% by weight, preferably 10 to 650% by weight.

The composition of the present invention may further contain a bisphenol compound. The content of the bisphenol compound is preferably 60% by weight or less of the epoxy resin. Examples of bisphenol compounds include 2,2'-bis(4-hydroxyphenyl)propane, 2,2'-bis(2-methyl-4-hydroxyphenyl)propane, and 2,2'-bis(4-hydroxyphenyl)propane.
Bis(4-hydroxyphenyl)methane, 1,1'-bis(4-hydroxyphenyl)ethane, 1,1'-bis(4-hydroxyphenyl)hexane, 1,1'-bis(4-hydroxyphenyl)docosyl , 2,2'-bis(4-hydroxyphenyl)butane, 2,2'-bis(
4-hydroxyphenyl)hexane, bis(4-hydroxyphenyl)sulfone, bis(3-chloro-4-hydroxyphenyl)sulfone, bis(3,5-dimethyl-4-hydroxyphenyl)sulfone, bis(4-
hydroxy-3,5-dibromophenyl) sulfone,
Bis(4-hydroxyphenyl) sulfide, bis(3
-methyl-4-hydroxyphenyl) sulfide, 1,
1-bis(4-hydroxyphenyl)cyclohexane,
Examples include, but are not limited to, 4,4'-dihydroxybenzophenone, dihydroxynaphthalene, and 1,4-(p-hydroxycumyl)benzene.

The epoxy resin composition of the present invention may optionally contain stress relievers, moisture resistance improvers, curing accelerators, mold release agents, flame retardants, thixotropy agents, dyes, oxidation stabilizers,
Light stabilizers, coupling agents, diluents, antifoaming agents, other resins, etc. can be blended.

Silicon compounds are commonly used as stress relievers. This silicon compound also acts as a moisture resistance improver. Silicone oil or silicone resin is used as such a silicone compound. These compounds include dimethyl silicone oil, olefin-modified silicone oil, polyether-modified silicone oil, alcohol-modified silicone oil, amine-modified silicone oil, epoxy-modified silicone oil, and silicone resins such as polyalkylphenylsiloxane and methylphenyl polymyl. Sesquioquinal, resins having hydroxyl groups, epoxy groups, amino groups, carboxyl groups, aniline groups, piperazine groups, etc. added to both ends of these polymers can be used. The amount of this silicon compound added to the epoxy resin is
A range of 1 to 190% by weight is preferred. If the amount is too large, the cured epoxy resin itself will lose its strength, making it unsuitable for the purpose of the present invention.

[0017] As the curing accelerator for the epoxy resin, phosphorus type, such as triphenylphosphine, and/or tertiary amine type, such as triethylamine, 1,8-diaza-bicyclo[5,4,0]-7, can be used. - Undesen (DB
U), N,N-dimethylbenzylamine, 1,1,3,
3-tetramethylguanidine, 2-ethyl-4-methylimidazole, N-methylpiperazine, etc., boron-based, for example, 1,8-diaza-bicyclo[5,4,0]-7-
Examples include, but are not limited to, undecenium tetraphenylborate.

As the mold release agent, for example, natural waxes,
Synthetic waxes, metal salts of linear fatty acids, acid amides, esters, paraffins, etc. Flame retardants include chlorinated paraffin, bromotoluene, hexabromobenzene, antimony acid oxide, etc. Coupling agents include silane cups A ring agent, a titanate coupling agent, an aluminum coupling agent, etc. are used.

The epoxy resin composition of the present invention can be prepared, for example, as follows. First, the block copolymer represented by formula (I) and an epoxy resin are dissolved in a solvent and heated to react, and then dried, and the epoxy resin, epoxy resin curing agent, inorganic filler and other additions are added as necessary Add and mix. Other methods include preparing the epoxy resin, curing agent, and block copolymer by simultaneously melting or mixing them using a solvent, or preparing a mixture of part of the curing agent and the block copolymer. , and then the remaining components may be added and mixed to prepare a curable epoxy resin composition.

The resin-sealed semiconductor device according to the present invention includes:
It can be easily manufactured by sealing a semiconductor chip using the above epoxy resin composition. Encapsulation is most commonly done by low pressure transfer molding, but
Sealing can also be performed by injection molding, compression molding, infrared curing molding, sheet molding, hot roll molding, pressurized heat molding, etc. The epoxy resin composition is cured by heating during sealing, and a resin-sealed semiconductor device is finally obtained which is sealed with a cured product of this composition. During curing, it is desirable to heat to 150° C. or higher. 150 again
Post-curing at ~300°C for several hours can improve properties such as heat resistance of the cured product. The post-cure temperature is preferably 170°C or higher, more preferably 200°C or higher, and the post-cure time is 3-16°C.
It's time.

The epoxy resin composition of the present invention includes a composition comprising a block copolymer epoxy resin and an inorganic filler as a curing agent before being heat-cured, and a cured product after heat-curing.

[0022]

[Examples] The present invention will be explained below with reference to Examples, but the present invention is not limited thereto. Synthesis Example 1 Synthesis of phenolic hydroxyl group-containing aramid-polybutadiene-acrylonitrile block copolymer (2 mol% of phenolic hydroxyl groups contained in the aramid part): 19.60 g (118 mmol) of isophthalic acid, 3,4'-oxydi 26.4 g (132 mmol) of aniline, 0.41 g (2.3 mmol) of 5-hydroxyisophthalic acid, 3.9 g of lithium chloride, 12.1 g of calcium chloride, 240 ml of N-methyl-2-pyrrolidone, and 54 ml of pyridine in 4 parts of 11. Pour into a Turo round-bottomed flask, stir to dissolve, add 74 g of triphenyl phosphite, and incubate at 90°C for 4 hours.
The reaction was carried out for a period of time to produce an integrated aramid oligomer containing a phenolic hydroxyl group. This is combined with a polybutadiene-acrylonitrile copolymer (H
ycar CTBN, manufactured by BF Goodrich. The acrylonitrile component contained in the polybutadiene acrylonitrile portion is 17 mol%, and the molecular weight is approximately 3600)4
A solution of 8 g dissolved in 240 ml of pyridine was added, and the reaction was further carried out for 4 hours, then cooled to room temperature, and the reaction solution was poured into methanol 201 to determine the content of the polybutadiene-acrylonitrile copolymer used in the present invention. is 50% by weight
An aramid-polybutadiene-acrylonitrile block copolymer containing about 2 mol% of phenolic hydroxyl groups was precipitated. This precipitated polymer was further purified by washing with methanol and refluxing the methanol. The intrinsic viscosity of this polymer is 0.85 dl/g (dimethylacetamide,
30°C). When the infrared spectrum of the polymer powder was measured by the diffuse reflection method, it was found that the absorption based on the amide carbonyl group at 1674 cm-1, the absorption based on the C-H bond of the butadiene moiety at 2856-2975 cm-1, and the absorption based on the C-H bond of the butadiene moiety at 2245 cm-1.
Absorption based on nitrile groups was observed in -1.

Synthesis Example 2 Synthesis of phenolic hydroxyl group-containing aramid-polybutadiene-acrylonitrile block copolymer (14 mol% of phenolic hydroxyl groups contained in the aramid part): Synthesis Example 1
of isophthalic acid 19.60 g (118 mmol), 3,
26.4 g (132 mmol) of 4'-oxydianine,
5-Hydoxyisophthalic acid 0.41g (2.3mmol
) and 48 g of polybutadiene-acrylonitrile copolymer having carboxyl groups at both ends, 19.93 g (120 mmol) of isophthalic acid, 30.63 g (153 mmol) of 3,4'-oxydianiline, and 5-hydroxyisophthalic acid. 3.64 (20 mmol) and polybutadiene-acrylonitrile copolymer with carboxyl groups at both ends (Hycar CTBN, BF Goodr
Manufactured by ich. The acrylonitrile contained in the polybutadiene acrylonitrile portion is 17 mol%, and the molecular weight is approximately 3.
600) Aramid-polybutadiene-acrylonitrile block copolymer containing about 14 mol% of phenolic hydroxyl groups used in the present invention was obtained by carrying out polymerization in the same manner except that 55.5 g was used, and by performing the same post-treatment. was precipitated. The intrinsic viscosity of this polymer was 0.82 dl/g (dimethylacetamide, 30°C). When the infrared spectrum of the polymer powder was measured using the diffuse reflection method, it was found that 1
Amidocarbonyl group at 675 cm-1, 2854-29
Absorption based on the C--H bond of the butadiene moiety was observed at 71 cm-1, and absorption based on the nitrile group was observed at 2243 cm-1.

<Synthesis of reaction product (A) of epoxy resin and block copolymer> Phenolic hydroxyl group-containing aramidopolybutadiene containing 2 mol% of phenolic hydroxyl groups obtained in Synthesis Example 1 in 25 g of dimethyl formaldehyde After dissolving 30 g of acrylonitrile block copolymer, orthocresol novolak type epoxy resin (Epikote 18
0 S65, epoxy equivalent: 205-220, manufactured by Yuka Shell Co., Ltd.) and 0.1 g of triphenylphosphine as a reaction accelerator were added, and the mixture was reacted at 90° C. for 2 hours. This was added to water to precipitate the resin, which was washed repeatedly with warm water. Tetrahydrofuran was then added to azeotrope these solvents under reduced pressure, and the resin was dried in vacuum, allowing the epoxy compound to react with the aramid part. A resin composition was obtained.

<Synthesis of reaction product (B) of epoxy resin and block copolymer> The aramidopolybutadiene-acrylonitrile block copolymer containing 2 mol% of phenolic hydroxyl groups in Example 1 was obtained in Synthesis Example 2. Approximately 14 phenolic hydroxyl groups
In place of the aramidopolybutadiene acrylonitrile block copolymer containing mol%, 7.1g of epoxy resin was added.
from 18g, triphenylphosphine 0.1g to 0.2
In place of Example 1, a similar operation was performed to obtain a composition of an aramidopolybutadiene acrylonitrile block copolymer and an epoxy resin.

<Synthesis of reaction product (C) of epoxy resin and block copolymer> From 30 g of the aramidopolybutadiene acrylonitrile block copolymer containing about 14 mol% of Example 2,
A composition of an aramidopolybutadiene-acrylonitrile block copolymer and an epoxy resin was obtained by performing the same operation except replacing the epoxy resin from 18g to 30g and 0.2g of triphenylphosphine to 0.3g. .

Composition (parts by weight) of each of the following raw materials shown in Table 1
After blending and heating and mixing, Examples 1 to 4 and Comparative Example 1
An epoxy resin composition for transfer molding was prepared. Reaction product A: Reaction product B: Reaction product C: Epoxy resin: Orthocresol novolak type epoxy resin (epoxy equivalent: 205-220) curing agent
: Phenol novolak resin (hydroxyl equivalent: 107) Bisphenol compound : 2,2'-bis(4-hydroxyphenyl)propane curing accelerator : Triphenylphosphine inorganic filler
: Fused silica flame retardant : Antimony trioxide colorant : Carbon black mold release agent : Carvanawax silane coupling agent : r-glycidopropyltrimethoxysilane

Using each of the epoxy resin compositions prepared as described above, transfer molding was carried out and curing was carried out at 90°C for 2 hours and at 200°C for 6 hours to form a 2 x 12 x 120 m
A sample of m was prepared. Using this sample, bending strength, bending elastic modulus, and maximum deflection until failure were measured. The results are shown in Table 1.

[Table 1]

The inorganic filler-containing epoxy resin composition of the present invention can produce cured inorganic filler-containing epoxy resin molded articles having improved toughness.

Claims (4)

[Claims] Claim 1: An epoxy resin composition containing a reaction product of a phenolic hydroxyl group-containing aramid-polybutadiene-acrylonitrile block copolymer represented by general formula (I) and an epoxy resin, an epoxy resin, a curing agent, and an inorganic filler. . [Formula 1] (where x=an integer of 3 to 7, y=an integer of 1 to 4, y/(
x+y)=0.1 to 0.3, z=an integer of 5 to 15, m
= integer from 1 to 400, n = integer from 1 to 400, n/(m
+n) = 0.01 to 0.50, 1 = integer of 1 to 50, A
r1 and Ar3 are divalent aromatic groups, and Ar2 is a divalent aromatic group containing a phenolic hydroxyl group). 2. The phenolic hydroxyl group-containing aramid-polybutadiene-acrylonitrile block copolymer represented by formula (I) is contained in an amount of 0.1 to 15% by weight based on the epoxy resin. Resin composition. 3. The resin composition according to claim 1 or 2, characterized in that the bisphenol compound is contained in an amount of 0.1 to 60% by weight based on the epoxy resin. 4. A resin-sealed semiconductor device, characterized in that a semiconductor chip is sealed with the resin composition according to claim 1, 2, or 3.