| 摘要 |
PURPOSE:To obtain a printed-wiring base material, which is low in dielectric constant, has a prescribed strength and is formed into an integral structure, by a method wherein a cloth consisting of hollow yarns made of a fluorine resin is impregnated with a reinforcing resin and is formed integrally with the reinforcing resin. CONSTITUTION:A printed-wiring base material 1 is one that a cloth 2 consisting of hollow yarns 3 is impregnated with a reinforcing resin 5, is hardened and is formed integrally with the resin 5, hollow parts 4 of the hollow yarns 3 have the air therein and a fluorine resin constituting the hollow yarns is one that a fluorine resin having a high dielectric constant is mainly copolymerized with a resin having a melting point lower than that of the fluorine resin and the melting point of the fluorine resin is made to drop. In order to improve the adhesion of the hollow yarns to the resin 5, the surfaces of the hollow yarns 3 are etched by a plasma etching method or the like, the occupation ratio of the hollow part 4 in each hollow yarn 3 is set at about 10 to 70% or thereabouts from the viewpoint of a reduction in the dielectric constant and the amount of impregnation of the resin 5 is set at an amount of 0.5 to 3g/cm<3> or thereabouts. Accordingly, a printed board, which is responded to the speedup of an electronic equipment, can be made using the printed-wiring base material, which is short in signal propagation time and is good in dimensional stability. |
