Patent ID: 6231800
Filing Date: 2001-05-15
Classification: B29C,B29K,C08G,C08L

Abstract:
A method of injection molding for epoxy resin moldings, comprising,charging a curable epoxy resin composition into a mini-sprue metal mold comprising a manifold part, a mini-sprue part, a product part, and an ejector-plate part,wherein the curable epoxy resin composition comprises epoxy resin, curing agent, curing accelerator, and inorganic filler, wherein the epoxy resin is at least one of the following types of epoxy resins: o-cresol type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, and hydroquinone type epoxy resin, and further wherein, the curable epoxy resin composition has the following latent curing properties:(1) a gel time at 80.degree. C. of at least 1,500 seconds,(2) a gel time at 100.degree. C. of at least 1,000 seconds, and(3) an activating energy for the curing reaction of at least 12,000 cal/mol;maintaining the temperature of the manifold part of said mini-sprue metal mold at a temperature at which the curable epoxy resin composition is in the molten state but less than the temperature at which the composition will cure; andinjection molding the curable epoxy resin composition in the product part of the mini-sprue metal mold.