Patent ID: 6165396
Filing Date: 2000-12-26
Classification: B29C

Abstract:
A method of obtaining a fiber-reinforced resin injection molding, comprising the steps of: injecting into a die having an internal cavity a molten resin obtained through the plasticization of a molding material; and introducing gas into the molten resin, the molding material comprising fiber-containing thermoplastic resin pellets which contain reinforcing fibers having a length of 2 mm to 100 mm, the reinforcing fibers accounting for 5% to 70% by weight of the molding material, the die including a movable die capable of advancing into and retracting from the internal cavity of the die, wherein after the injection of the molten resin into the die cavity is started, the movable die is retracted to a position where the die cavity assumes a volume corresponding to the molding, and gas is introduced into the molten resin filling the die cavity, wherein the molding material contains at least fiber-containing thermoplastic resin pellets which have a length of 2 mm to 100 mm and which contain reinforcing fibers having a length equal to that of the resin pellets and arranged in parallel to one another in an amount of 20% to 80% by weight.