PREPREG FOR PRINTED WIRING BOARD AND PRODUCTION OF COPPER-CLAD LAMINATE

摘要

PURPOSE:To obtain the title prepreg improved in drillability, resistance to thermal discoloration, storage stability and heat resistance by impregnating a (non)woven glass cloth with a specified varnish and drying the cloth. CONSTITUTION:A varnish is obtained by mixing 100 pts.wt. epoxy resin containing 1-100wt.% glycidyl ether of a polycondensate (maximum molecular weight of 10000 or below) between bisphenol A or bisphenol F and formaldehyde with 1-100 pts.wt. polycondensate (maximum molecular weight of 1000 or below) between bisphenol A and formaldehyde, 0.01-5 pts.wt. cure accelerator and a solvent. The varnish is optionally aged by heating under agitation at 50-70 deg.C for at least 1hr and cooled to room temperature. A (non)woven glass cloth is impregnated with the cooled varnish and dried at 80-200 deg.C to obtain the title prepreg.