| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a resin plate low in strain, excellent in the dimensional precision of a hole and provided with the hole by injection molding in a state that a weldline disappears. SOLUTION: The hole is provided to a part of a cavity wall part, a movable mold 1 having the hole pin 5 inserted in the hole to reciprocally move and a fixed mold 3 are clamped to form a molding cavity, the molten thermoplastic resin 8 is injected and charged into the cavity in a state that the pin 5 is perfectly inserted in the hole and the surface of the cavity wall part is substantially flat, the hole pin 5 subsequently is protruded from the hole at the point of time when the temperature of a resin core layer is glass transition temperature +30°C or above to be pushed in the cavity, the hole pin 5 is perfectly returned into the hole in the mold after the temperature of the core layer is cooled to the glass transition temperature or below to form the hole to the molding resin corresponding to the hole pin 5 and a molded body is subsequently separated from the mold to manufacture a resin molded body having the hole, especially the resin plate having the hole. COPYRIGHT: (C)2008,JPO&INPIT |
