Abstract: The epoxy resin composition according to the invention contains an epoxy resin and/or an epoxy compound, a curing agent, a curing accelerator and an inorganic filler as main components. The inorganic filler has a particle size of a maximum particle diameter of not more than 10 &mgr;m and a mean particle diameter of not more than 3 &mgr;m and a slope n of not more than 4.0 in its particle size distribution that is expressed by a Rosin-Rammler's (RRS) diagram, and is contained in the resin composition in an amount of not less than 30% by weight and not more than 85% by weight based on the total amount of the resin composition. The slope n is preferably not less than 1.0. The resin composition is preferable for transfer molding or injection molding. This composition is free from deterioration of moldability caused by lowering of flowability and is excellent in mold-transferring properties and excellent dimensional stability.

Abstract: Disclosed is a method of injection-molding for epoxy resin moldings wherein an epoxy resin composition is used as starting material, a molding cycle is shortened, a continuous molding operation is possible and a waste portion after curing can be minimized as well as an injection-moldable epoxy resin composition excellent in thermal stability possessing latent-type curing characteristics capable of rapidly promoting curing reaction in a metal mold without being cured in an injection molding machine. The aforesaid method is carried out by charging an epoxy resin composition possessing the latent-type curing characteristics into a mini-sprue metal mold which is composed of a manifold part, a mini-sprue part and an ejector-plate part and wherein a metal mold temperature at the manifold part is so maintained that the epoxy resin composition is molten but curing of the composition is not promoted, and injection-molding the composition.

Abstract: Disclosed is an epoxy resin composition which is excellent in thermal stability without being cured in a cylinder of an injection molding machine and is extremely suppressed in the formation of flux on molding.This epoxy resin composition has an important feature residing in the use of a specific silica of the following characteristics as an inorganic filler to be incorporated thereinto whereby excellent technical effects can be achieved such as the composition being injection-moldable and the formation of flux on molding being suppressed extremely:(a) an average particle diameter of not more than 30 .mu.m,(b) 5-30% by weight of a molten or crystalline silica powder having an average particle diameter of not more than 7 .mu.m and a specific surface area of at least 5 m.sup.2 /g in the total silica content,(c) 15-45% by weight of silica having an average particle diameter of not more than 5 .mu.m in the total silica content,(d) the maximum particle diameter of the total silica content of not more than 150 .mu.

Abstract: Disclosed is an epoxy resin composition comprising, as basic components, (A) an epoxy resin, (B) a phenol-novolak resin, (C) a curing promotor and (D) a filler. Pulverized or spherical silica having specific particle size characteristics is used as the filler (D). Preferably, a halogenated epoxy resin and antimony oxide are further incorporated in this epoxy resin. This epoxy resin composition shows a very small molding shrinkage. If a dialkylurea derivative is used as the curing promotor (C), the stability of the composition at about 100.degree. C. is drastically improved and the flowability of the composition is improved. Accordingly, precision injection molding becomes possible, and the effect of sealing a semiconductor is enhanced.

Abstract: An epoxy resin composition comprising a trifunctional epoxy resin derived from a trisphenol having the structure represented by the following general formula ##STR1## wherein R represents a hydrogen atom, an alkyl group or a halogen atom, and a novolak-type phenolic resin. This epoxy resin composition gives a cured product having excellent pliability and a high glass transition temperature. It is especially useful as a semiconductor encapsulating material.