| 摘要 |
The present invention relates to an injection-compression-molding method, and more particularly to an injection-compression-molding method which is most suitably applied to thermoplastic resin being high in melting viscosity and low in fluidity, and has as its object the provision of an excellent molding, in which occurrences of crazing, cracking, delamination and so forth due to the shrinkage as a result of residual stress caused by molecular orientation of material resin or due to the stress strain are restricted. Another object of the present invention is to improve a work efficiency by simplifying the molding process. A pressing pressure is applied from behind a cavity to shrink the cavity to a volume less than that of an intended molding, plasticized synthetic resin is injection-compression-filled into the cavity, and thereafter, when the pressure which has been applied from behind the cavity, is lowered, the volume of the cavity is expanded by the elastic restoring force of the plasticized synthetic resin compressed and filled into the cavity. Subsequently, after the elastic restoring force is decreased, the cavity is shrunk to the volume of the intended molding. <IMAGE> |
