Filler-containing resin composition suitable for injection molding and

Abstract

A molding resin composition containing, in a resin, a filler comprising a globular powder of which mean particle diameter is not smaller than 0.1 .mu.m and not greater than 1.5 .mu.m (x component), a globular powder of which mean particle diameter is not smaller than 2 .mu.m and not greater than 15 .mu.m (y component) and a globular powder of which mean particle diameter is not smaller than 20 .mu.m and not greater than 70 .mu.m (z component), wherein proportions of the x, y and z components based on the total volume of x, y and z components are not smaller than 10% by volume and not greater than 24% by volume, not smaller than 0.1% by volume and not greater than 36% by volume and not smaller than 57% by volume and not greater than 76% by volume, exhibits an excellent fluidity even when loaded with a high percentage of filler. Further, their cured products are lowered in the moisture absorption and thermal expansion coefficient of which increases result from the resin itself present in the cured product. Further, a semi-conductor package sealed with the resin composition exhibits a high package crack resistance. The resin composition is suitable for use as a sealing material for semi-conductors, and extensively applicable to other uses requiring a high-percentage loading of filler.