| 摘要 |
<p>PURPOSE:To obtain a laminated sheet having a uniform thickness and reduced in coefficients of dimensional fluctuation, warpage and distortion, by a method wherein a plurality of sheets to be laminated each containing 500 or less air bubbles/cm<2> are inserted between two running belts to be heated under pressure through the running belts. CONSTITUTION:The impregnation of a base material with a resin is performed under reduced pressure in a varnish tank reduced in pressure or performed by passing the base material between two upper and lower rolls arranged in the varnish tank under pressure and subsequently releasing pressure. By performing said impregnation under pressure or reduced pressure, the involution of air bubbles in the base material within the varnish tank can be reduced. After the base material is impregnated with the resin by this method, said base material is dried at 100-160 deg.C to obtain a resin impregnated base material containing 500 or less air bubbles. Thereafter, a required number of the resin impregnated base materials being sheets to be laminated are stacked and a metal foil is arranged to both surfaces or single surface of the stacked one to obtain one set and a plurality of sets are held between two upper and lower advance running belts and heated, for example, at 150-170 deg.C under pressure of 10-30kg/cm<2> and a laminated sheet is obtained by continuous molding due to so called double belt press.</p> |
