| 摘要 |
PURPOSE:To prevent a linear hollow by a method wherein a prepreg, whose minimum melt viscosity is high when it is melted at a heating and pressurization operation, is used as a prepreg coming into contact with an outer-layer copper layer in which the linear hollow is produced. CONSTITUTION:At a copper-clad laminated board, for multilayer printed-circuit board use, where an outer-layer copper foil is arranged, via a prepreg layer, on a laminated board on which a circuit for inner-layer use has been formed, the minimum melt viscosity of a prepreg coming into contact with the outer-layer copper foil is set to 2000 to 3000 poises at a temperature-rise rate of 3 deg.C/min, and the minimum melt viscosity of a prepreg coming into contact with the laminated board for inner-layer circuit use is set to 1500 poises or lower at a temperature-rise rate of 3 deg.C/min. Prepregs A coming into contact with outer-layer copper foils 2 are combined with prepregs B coming into contact with a double-sided inner-layer circuit formation board 1; a four-layer printed-circuit board constituent body 3 is constituted. Eight sets in which stainless-steel sheets 4 have been piled up alternately are arranged between upper and lower heating plates 6 via cushions 5; they are heated, pressurized and shaped; a copper-clad laminated board for printed-circuit board use is obtained. |
