RESIN COMPOSITION FOR PRINTED WIRING BOARD, PREPREG, LAMINATE, AND PRINTED WIRING BOARD MADE WITH THE SAME

摘要

An epoxy resin composition for printed wiring boards which comprises an epoxy resin, a phenolic novolak, a curing accelerator, and a silica filler, characterized in that the silica filler has a shape having at least two planes and has an average particle diameter of 0.3 to 10 mum and a specific surface area of 8 to 30 m2/g. The epoxy resin composition has a higher apparent viscosity than the resins and can hence be inhibited from sagging in a drying oven. This composition retains the intact property of infiltrating into reinforcements because the viscosity of the resins themselves has not increased locally. The composition hence produces the effect of improving the appearance of a prepreg.