PREPREG FOR PRINTED WIRING BOARDS, RESIN VARNISH, RESIN COMPOSITION, AND LAMINATE FOR PRINTED WIRING BOARDS PRODUCED BY USING THESE SUBSTANCES

摘要

Printed wiring boards improved in the drilling processability and insulation properties are produced either by treating the surfaces of base materials or inorganic fillers with silicone oligomers having specified structures, particularly, a three-dimensionally crosslinked silicone oligomer, or by using resin varnish prepared by compounding such a silicone oligomer with a resin varnish for impregnation of the base materials, or by dipping the inorganic fillers in a solution of such a silicone oligomer for surface treatment and then directly compounding resin materials with the solution.