VERFAHREN ZUR HERSTELLUNG VON FORMTEILEN

摘要

The method of compression molding an article such as a closure wherein a thermoplastic resin is mixed with additives including a metallic pigment additive, extruded through a nozzle, cut by a blade into individual pellets, and each pellet is deposited into the cavity of a mold which is then closed to compression mold the pellet into an article, including the step of adding a blowing agent to the resin prior to extrusion in a quantity sufficient to randomize the metallic particles in the metallic pigment additive such that gaseous bubbles are provided in the extruded melt and that the gaseous bubbles are substantially expelled during the compression molding resulting in an article that is substantially free of blemishes which normally occur. Preferably, the method includes positioning a mixer plate in the path of the resin immediately prior to the nozzle.