PREPREG AND METAL FOIL-CLAD LAMINATE

摘要

PROBLEM TO BE SOLVED: To obtain both a prepreg without unevenly distributing an inorganic filler when producing the prepreg and a metal foil-clad laminate having a small coefficient of thermal expansion and a small anisotropy of the thermal expansion. SOLUTION: This prepreg is obtained by impregnating a glass woven cloth prepared by regulating the ratio of the number of warp yarns/number of picked weft yarns to 1.0-1.2 number of warp yarns/weft yarns with a varnish prepared by mixing a treating agent solution containing an inorganic filler and obtained by adding the inorganic filler to a treating agent solution containing one or more kinds of treating agents selected from a silane-based coupling agent, a titanate-based coupling agent and a silicone oligomer having <=2 siloxane recurring units in the molecule and having functional groups at the terminals with a resin material and drying the impregnated glass woven cloth. The metal foil-clad laminate is prepared by superimposing a metal foil on the prepreg and hot-pressing the resultant laminate.