EPOXY RESIN COMPOSITION FOR IMPREGNATING INTO ORGANIC FIBER SUBSTRATE AND PREPREG, LAMINATE AND PRINTED CIRCUIT BOARD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a new epoxy resin composition which can be combined with organic fiber substrates to form insulated layers that allow printed circuits to hold excellent adhesive forces and heat resistance. SOLUTION: This epoxy resin composition which is impregnated into organic fiber substrates to form insulated layers is characterized by comprising (a) a trifunctional epoxy resin, (b) a cresol novolak epoxy resin, and (c) a urethane structure-containing bifunctional epoxy resin, wherein a compounded weight ratio (a)/ (b) is 90/10 to 50/50, and the content of the component (c) in the solid resin is 5 to 30 wt.%. The organic fiber substrate to be impregnated with the epoxy resin composition is preferably a non-woven fabric form prepared by binding fibers containing poly-p-phenylene terephthalamide fibers as a main component with fibers obtained by fibrillating poly-m-phenylene isophthalamide fibers.