UNSATURATED RESIN COMPOSITION FOR USE IN PRESSURE MOLDING

摘要

UNSATURATED RESIN COMPOSITION FOR USE IN PRESSURE MOLDING The invention concerns an unsaturated resin composition for use in pressure molding. The composition comprises an unsaturated polyester resin or a poly(meth)acrylate of an epoxy resin, and fillers consisting essentially of (a) a calcium carbonate powder which passes through a 325 mesh sieve, (b) an inorganic mineral particulate which passes through a 12 mesh sieve and is retained on a 200 mesh sieve, and (c) glass fibers having a length larger than 0.2 mm, wherein the ratio by weight of (a) to (b) is within the range of from 0.3:1 to 10:1, the ratio of (a) + (b) to the unsaturated polyester resin is within the range of from 1.5:1 to 7:1, and the ratio of (c) to the total weight of the resin, calcium carbonate, silica sand and glass fiber is within the range of from 0.01:1 to 0.25:1. The composition is able to fill small cavities or crevices in the mould dies to produce an accurately molded article.