FLUORORESIN FIBER SHEET, METAL-CLAD SUBSTRATE FOR PRINTED CIRCUIT BOARD USING THE SHEET AND METHOD FOR PRODUCING THE BOARD

摘要

PROBLEM TO BE SOLVED: To provide a metal-clad substrate which scarcely has the partial irregularity of relative dielectric constant and dielectric loss tangent and has a high adhesive force between the metal foil and the substrate and whose surface is smooth in a state free from fine evenness. SOLUTION: This fluororesin fiber sheet comprising at least two kinds of fluroresin fibers A and B having different melting points, respectively, and heat-resistant insulating fibers is characterized in that the melting point MpA of the fluroresin fibers A and the MpB of the fluroresin fibers B satisfy the following expression (1): MpA-MpB>0 (1). COPYRIGHT: (C)2004,JPO