JPS6136844B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an epoxy resin composition that provides a cured product having a low modulus of elasticity, a low coefficient of expansion, and a high glass transition point. In recent years, in the field of electronic components, with the trend toward smaller size, lighter weight, and higher reliability, there has been a trend towards increased functionality by increasing the size of semiconductor element pellets and combining active and passive elements. Therefore, there is a strong demand for resin materials for molding various elements to have the property that the effect of stress on the insert is small even when directly molded. Conventionally, epoxy-based, silicone-based, phenol-based, diallyl-based materials, and the like have been used as molding resins for electronic components such as semiconductors and electrical equipment. Among these, epoxy resin compositions using phenol novolac resin as a curing agent are the mainstream resins for molding because they have well-balanced adhesiveness to inserts and electrical properties. However, if this type of resin composition is directly molded with the resin without applying a flexible protective coat to the element pellet, the element pellet may crack or the bonding wires may be cut. Failures due to stress on the insert are observed. As a countermeasure, it is important to reduce the stress exerted on the insert, and it is necessary to develop a molding resin that has a low modulus of elasticity, a low coefficient of expansion, and a high glass transition point. Addition of a flexibilizing agent may be considered as one means of lowering the modulus of elasticity of the mold resin. However, if this method is applied to epoxy resin compositions that use phenolic resin as a curing agent, the glass transition point of the cured resin will drop rapidly, and the electrical properties in high-temperature regions will decrease accordingly, making it difficult to use highly reliable molds. The product is difficult to obtain. On the other hand, silicone-based materials have a low elastic modulus and a high glass transition temperature, and even if they are directly molded, no cracks will occur in the element pellets. However, this material has problems such as poor adhesion to the insert and high moisture permeability, making molded products unreliable in terms of moisture resistance. The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a material having a low elastic modulus, a low coefficient of linear expansion, and a high glass transition point, for example, 1.5×10 ⁵ Kg/cm ² or less, respectively. (room temperature), 3.0×10 ^-5 (℃
^-1 ) To provide an epoxy resin composition that cures into a resin having properties below and above 150°C. The epoxy resin composition of the present invention comprises the following (A) to (C): (A) a polyfunctional epoxy compound, (B) diglycidyl ester of dimic acid, (C) a p-vinylphenol polymer and a halogenated p- An epoxy resin composition comprising: at least one polymer selected from vinylphenol polymers;
Alternatively, a compound selected from the following (A) to (D) (A) polyfunctional epoxy compound, (B) diglycidyl ester of dimic acid, (C) p-vinylphenol polymer and halogenated p-vinylphenol polymer (D) an inorganic filler, provided that the inorganic filler (D)
is an epoxy resin composition characterized in that (D)/(A)+(B)+(C)+(D)×100 contains 40 to 78% by volume. In the present invention, examples of polyfunctional epoxy compounds include diglycidyl ether of bisphenol A, butadiene epoxide, 3,4-epoxycyclohexylmethyl-(3,4-epoxy)cyclohexanecarboxylate, vinylcyclohexane dioxide, 4,4'- Di(1,2-epoxyethyl)diphenyl ether, 4,4'-(1,
2-epoxyethyl)biphenyl, 2,2-bis(3,4-epoxycyclohexyl)propane,
Glycidyl ether of cresorcin, diglycidyl ether of phloroglucin, diglycidyl ether of methylphloroglucin, bis-(2,3-
epoxycyclopentyl)ether, 2-(3,
4-epoxy)cyclohexane-5,5-spiro(3,4-epoxy)-cyclohexane-m-dioxane, bis-(3,4-epoxy-6-methylcyclohexyl)adipate, N,N'-m-
Bifunctional epoxy compounds such as phenylenebis(4,5-epoxy-1,2-cyclohexane)dicarboximide, triglycidyl ether of para-aminophenol, polyallyl glycidyl ether, 1,3,5-tri(1,2-epoxy) ethyl)benzene, 2,2',4,4'-tetraglycidoxypenzophenone, tetraglycidoxytetraphenylethane, polyglycidyl ether of phenol formaldehyde novolak, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane. Trifunctional or higher functional epoxy compounds such as glycidyl ether are used. One or more of these epoxy compounds can be used,
In particular, it is advantageous to use a bisphenol A diglycidyl ether compound and a phenol novolak type compound in combination. Next, as diglycidyl esters of dimaic acid, diglycidyl esters of polymerized acids synthesized from linoleic acid, oleic acid, castor oil fatty acids, etc. are used. The blending of these glycidyl esters contributes to lowering the elastic modulus of the cured resin, but if the amount is too large, some of them will remain without participating in the curing reaction, causing oozing and poor appearance. Therefore, it is desirable to blend it within the same weight as the polyfunctional epoxy compound. The relationship between the polyfunctional epoxy compound and the diglycidyl ester of dimic acid is that the former is 20 to 90 parts by weight of novolac type epoxy resin and 5 to 40 parts by weight of bisphenol A epoxy resin, and the latter is 5 to 40 parts by weight. %, and the weight ratio of the former (polyfunctional epoxy compound) is preferably larger than the weight ratio of the latter (diglycidyl ester of dimic acid). In the present invention, the p-vinylphenol polymer and the halogenated p-vinylphenol polymer play an important role in achieving the object of the invention. That is, by using the above polymer, the glass transition point Tg can be maintained at 150°C or higher and stress can be reduced. Preferably, the function of the present invention can be achieved if the epoxy component is added in a stoichiometric ratio of one OH group to one epoxy group. The epoxy component and the p-vinylphenol polymer may be mixed for each component, or may be heated and melted and mixed in advance. Addition of an inorganic filler is also essential to achieving the objectives of the present invention. For example, zircon,
Silica, fused silica glass, alumina, aluminum hydroxide, glass, quartz glass, calcium silicate, gypsum, calcium carbonate, magnesite, clay kaolin, talc, mica, asbestos, lead acid compound, zinc white, titanium white, Molybdenum sulfide, carbon black, etc. can be used. The inorganic filler gives the cured resin the desired elastic modulus,
It is blended in an amount sufficient to provide a glass transition point and an expansion coefficient. Generally, the elastic modulus is 1.5×10 ⁵ Kg・
cm ^-2 or less (room temperature), glass transition point 150℃ or higher, expansion coefficient 3.0×10 ^-5 (℃ ^-1 ), 40 to 75% by volume
(based on the total amount of the composition). In reality, it differs slightly depending on the type of inorganic filler.
If the blending amount is excessively increased, the fluidity of the composition will decrease. Furthermore, a known catalyst that promotes the curing reaction of epoxy resin can be added to the resin composition of the present invention. Such catalysts include, for example, tertiary amines such as triethanolamine, tetramethylbutanediamine, tetramethylpentanediamine, tetramethylhexanediamine, triethylenediamine, dimethylaniline, and oxyalkyl amines such as dimethylaminoethanol and dimethylaminopentanol. There are amines such as amines, tris(dimethylaminomethyl)phenol, and N-methylmorpholine. Also, cetyltrimethylammonium bromide, cetyltrimethylammonium chloride,
dodecyltrimethylammonium iodide,
Quaternary ammonium salts such as trimethyldodecyl ammonium chloride, benzyldimethyltetradecylammonium chloride, benzylmethylpalmitylammonium chloride, allyldodecyltrimethylammonium bromide, benzyldimethylstearylammonium bromide, stearyltrimethylammonium chloride, benzyldimethyltetradecylammonium acetate, etc. be. 2-ethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-methyl-4-ethylimidazole, 1
-Butylimidazole, 1-propyl-2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole , imidazoles such as 1-azine-2-methylimidazole and 1-azine-2-undecylimidazole, triphenylphosphine tetraphenylborate, tetraphenylphosphonium tetraphenylborate triethylamine tetraphenylborate, N-methylmorpholine Tetraphenylborate, pyridine tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, 2-ethyl-1,4-
Tetraphenylboron salts such as dimethylimidazole tetraphenylborate are also useful. In addition, higher fatty acids, mold release agents such as waxes, epoxy silane, vinyl silane,
Coupling agents such as borane compounds and alkoxy titanate compounds can be used. Furthermore, flame retardant materials made of antimony, phosphorus compounds, etc. can be used. Next, the present invention will be specifically explained using examples. Example A polyfunctional epoxy compound, a diglycidyl dimic acid ester, a p-vinylphenol polymer, and a halogenated p-vinylphenol polymer were blended in the proportions shown in Tables 1 and 2. The polyfunctional epoxy compounds used were novolak type epoxy resin DEN438 (manufactured by Dow Chemical Company, epoxy equivalent weight 179), bisphenol A type epoxy resin Epicoat 1002 (manufactured by Ciel Company, epoxy equivalent weight 650),
In addition, dimate diglycidyl ester Epicoat
871 (manufactured by Ciel). Further, the p-vinylphenol polymer and the halogenated p-vinylphenol polymer are Resin M and -Resin MB (manufactured by Maruzen Sekiyu Co., Ltd., OH equivalent: 120). Furthermore, in addition to fused silica glass powder as an inorganic filler, a curing catalyst, tetraphenylphosphonium tetraphenylborate (hereinafter referred to as TPP-K) (manufactured by Hokko Chemical Co., Ltd.), and a mold release agent Hoechstwax E
(manufactured by Hoechst Japan Co., Ltd.), coupling agent KBM
-403 (manufactured by Shin-Etsu Chemical Co., Ltd.) and the colorant carbon black were also added. Next, the mixture containing the above ingredients was heated to 70°C.
After kneading for about 10 minutes with heated rolls at ~80°C, the mixture was coarsely pulverized to prepare the intended epoxy resin composition for molding. These compositions were heated at 180°C, 70Kg/cm ² , 1.5-3
A cured specimen was prepared by transfer molding under the conditions of 180°C for 6 hours, and its various properties were measured. The results were as shown in Tables 2 and 4.
Note that the spiral flow in the table is the value (in inches) when molded at 180°C for 1.5 minutes, and the hardness is the value of Bacall hardness No. 935 immediately after molding under the same conditions and release from the mold.

【table】

【table】

[Table] In Tables 1 and 2, glass transition point, elastic modulus, and coefficient of linear expansion except for No. 1, which has a large amount of dimic acid diglycidyl ester, and No. 7 and 8, which have a very small amount or do not contain it. It shows favorable properties as a molding resin with balanced properties. On the other hand, in No. 1, the hardness of the cured product was low, and the dimate ester seeped out onto the surface of the molded product, resulting in poor appearance.
Further, in Nos. 7 and 8, the elastic modulus of the cured product is high and comparable to that of the conventional example. Next, Tables 3 and 4 show examples in which the amount of filler added was changed. In No. 12, which contains 35% by volume of quartz glass powder as a filler, the linear expansion coefficient of the molded cured product is 3.5 × 10 ^-5 °C ^-1 , and when the content is increased to 80% by volume, that of No. As a result, fluidity is significantly reduced, making it difficult to obtain good molded products. In order to prepare a molding resin with favorable properties, it is necessary to adopt a filler loading between 40 and 75% by volume, which is in the middle of the above examples.

【table】

【table】

Claims (1)

[Scope of Claims] 1. At least one member selected from (A) a polyfunctional epoxy compound, (B) diglycidyl ester of dimic acid, (C) a p-vinylphenol polymer and a halogenated p-vinylphenol polymer. An epoxy resin composition comprising a polymer. 2 (A) polyfunctional epoxy compound, (B) diglycidyl ester of dimic acid, (C) p-vinylphenol polymer and halogen p
- at least one polymer selected from vinylphenol polymers, (D) an inorganic filler, provided that the inorganic filler (D)
An epoxy resin composition comprising 40 to 75% by volume of (D)/(A)+(B)+(C)+(D)×100. 3. The components (A) and (B) are (A) 20 to 90 parts by weight of novolak type epoxy resin, 5 to 40 parts by weight of bisphenol A type epoxy resin, and (B) 5 to 40 parts by weight of diglycidyl ester of dimic acid. The weight ratio of both (A) and (B) is (A)>
(B) The epoxy resin composition according to claim 2.