VARNISH FOR LAMINATE OR PREPREG, LAMINATE OR PREPREG OBTAINED WITH THIS VARNISH, AND PRINTED CIRCUIT BOARD MADE WITH THIS LAMINATE OR PREPREG

摘要

A varnish for laminates or prepregs, characterized by comprising (d) an inorganic filler and a composition obtained by mixing (a) an epoxy resin, (b) a dicyandiamide, and (c) a compound having an imidazole ring in such a proportion that the content of the ingredient (c) is 0.001 to 0.03 wt.% based on the ingredient (a) and reacting the mixture in an organic solvent at a temperature of 70 DEG C to 140 DEG C, excluding 140 DEG C, to heat-treat the mixture so that the two ingredients are compatibilized in the absence of a solvent; a flame-retardant laminate or prepreg for electrical insulation which is obtained with the varnish; and a printed circuit board.