| 摘要 |
PURPOSE:To produce fluororesin laminated sheet, the permittivity of which is small, by a method wherein metal foil is laminated onto one side or both sides of fluororesin-impregnated fiber base material layer, which contains fine inorganic filler powder having specified physical properties, so as to be made into an integral body under heat and pressure. CONSTITUTION:Water soluble dispersing liquid of fluororesin is prepared, to which fine inorganic filler powder having characteristic values such as permittivity of 2 - 4, specific gravity of 1.5 - 3.0, mean particle diameter of 0.05 - 9mum and thermal expansion coefficient of (2 - 20)X10<-6>/ deg.C is added. After fiber base material is impregnated with said water soluble dispersing liquid of fluororesin, fluororesin prepregs consisting of the impregnated base material are laminated to one another so as to provide metal foil on both sides or one side of it in order to be made into an integral body under heat and pressure, resulting in producing fluororesin laminated sheet. Concretely, copper-clad lami nated sheet, which is produced by integrating copper foils 1 on outer surfaces with fluororesin base material layer 2, to which fine molten silica powder is added and which is formed on the inner surface of each of the foils, is exam pled. |
