摘要 |
The invention provides fluororesin fiber paper excellent in adhesion to a copper foil, heat resistance, chemical resistance, low water absorption and electric insulation and capable of being used as a substrate of a printed board suitable for use in high frequency, of which a low dielectric loss is required. The fluororesin fiber paper is a porous sheet obtained by forming a slurry comprising fluororesin fiber into a sheet by a wet paper making method and sintering the resultant sheet and has an average pore diameter of 0.5 to 50 mum and a maximum pore diameter of at most 250 mum. A copper-clad laminate for printed board is produced by laminating the fluororesin fiber paper and a copper foil having a ten point mean height of surface roughness profile (Rz) of 0.5 to 8.0 mum on each other by means of vacuum hot pressing. |