PURPOSE: To simply mold a synthetic resin material in a short time by a method in which a thermoplastic resin sheet is thermally molded into a surface skin, and a synthetic resin for core is injected and hardened on the surface skin by a reactive injection molding method in such a way as to integrate the surface skin with the core.
CONSTITUTION: A thermoplastic synthetic resin sheet (e.g., of polyethylene, polystyrene, polyethylene terephthalate, etc.) having a thickness of 0.05W10mm is thermally molded by vacuum molding, compression molding, etc., to form a surface skin by using mold of aluminium, iron, heat-resistant resin, etc. A synthetic resin material for core is injected and hardened in the mold with the surface skin by a reactive injection molding (RIM) method to obtain a composite molding by integrally combining the surface skin and the core by only one mold through all the processes. In the RIM process, according to resins used, polyurethane RIM, nylon RIM, etc., may be used.
FUKUNAGA TOMIAKI
SOGI HIDEHITO
FUKUSHIMA SHIGEYOSHI
| JPS5757640A | 1982-04-06 |