EPOXY RESIN COMPOSITION FOR IMPREGNATING ORGANIC FABRIC BASE, PREPREG USING THE SAME, LAMINATED BOARD AND PRINTED CIRCUIT BOARD

摘要

PROBLEM TO BE SOLVED: To provide an epoxy resin composition that is flame-retardant despite of free from halogen, causes no deterioration in the tear strength of the copper foil and heat resistance and is suitable for printed circuit boards with organic fabric base. SOLUTION: The epoxy resin composition for impregnating organic fabric base material comprises a trifunctional epoxy resin and a phenol novolak type epoxy resin at a weight ratio of 90/10-50/50 wherein the phosphorus content is 1.8-2.6 mass % in the resin solid components. The organic fabric base is impregnated with the epoxy resin composition to form the insulation layer in which the organic fabric base comprising a para-type aramid fiber as the main component are integrally bonded into a nonwoven fabric with the first thermosetting binder and the second binder selected from the chopped fiber, fiber pulp and fibrid of a thermoplastic resin having >=220 deg.C softening point. The para-type aramide fiber means the pulp of poly-p-phenylene terephthalamide or the chopped fiber and the pulp of poly-p-phenylene terephthalamide.