| 摘要 |
PURPOSE:To eliminate the loss of sheet and facilitate the realization of perfect sealing by a method wherein molding materials, between which curable prepreg is interposed, are seated within a pressure vessel under the state that the sides of the seated materials are respectively surrounded by a frame having nearbly U-shape in cross section and a sheet is stretched over the frame in tension, and, after that, integrally molded under heat and pressure. CONSTITUTION:Molding materials 2 for multilayer printed wiring board are placed on a base plate 3, which is arranged within a pressure vessel and has a vent hole 4 and the periphery of which is surrounded by a frame 5 having nearly U-shape in cross section, a sheet 1 and an air bag 6. The sheet 1 and the frame 5 and the frame 5 and the base plate 3 respectively brought into close contact with each other by sealing materials 7. By evacuating through the vent hole 4 and a piping 34a, the periphery of the molding materials 2 attains vacuum, resulting in expanding the air bag 6 so as to fill the gap between the frame 5 and the molding materials 2. Each molding material 2 is produced by laminating inner layer printed wiring board, prepregs made of curable resin-impregnated glass mat base material and copper foil laminate to one another in multiplayers and finally integrated by curing under heat and pressure. |
