| 摘要 |
PURPOSE:To obtain a molded piece free from mold cavities and rich in thickness at low compression by a method wherein thermoplastic resin is defoamed under repeated change of compression between the highest softening temperature and the lowest melting temperature, then, heated to the highest melting temperature or higher to make compression molding. CONSTITUTION:In the compression molding of thermoplastic resin material, variation of compression is repeated keeping the highest softening temperature in the minimum and the lowest melting temperature in the maximum to defoam the material. Then, the defoamed material is heated to the highest melting temperature in the minimum to be compression-molded into the desired thick molded piece. Additionally, thermoplastic resin material is molded in a mold using several laminated sheets or films or pellets or equivalents. In this manner, it becomes possible to manufacture a thick molded piece free from mold cavities at low compression. |
