GAS INJECTION MOLDING METHOD FOR FIBER REINFORCED RESIN AND MOLDED PRODUCT

摘要

PROBLEM TO BE SOLVED: To provide a gas injection molding method and a molded product thereof in which the mechanical properties and the outer appearance quality are superior and the manufacture of a lightweight product is achieved regardless of the shape of the molded product. SOLUTION: A raw material containing reinforcing fibers of the length in the range of 2-100 mm of 5-70 wt.% and a mold 10 provided with a movable mold 10B movable forward and backward for a cavity 10C inside is used, and after starting the injection of molten resin into the mold 10, the movable mold backward movement for moving the movable mold 10B back to a position S on which the cavity 10C is provided with the volume corresponding to a molded product and the gas injection operation for injecting gas into the molten resin fed in the cavity 10C are carried out. The mechanical properties are improved by the reinforcing fibers, and the lightweight is realized by expanding based on the spring-back phenomenon, and the generation of sink marks are prevented by the gas injection and the cooling efficiency is improved.