| 摘要 |
PURPOSE: To improve the shaping properties, the heat resistance, the strength of a molded form by previously heating the molding surface of a mold to a set mold temperature or higher to the crystal melting point or lower of resin before blow molding in a method for orientation blow molding a plastic vessel. CONSTITUTION: In a blowing mold having means for circulating a jig for covering a parison between a heating chamber and a blow molding machine 2, a plurality of molds 8 and corresponding mold heaters 7 are provided on a rotary table 21. The rotary range of the mold 8 is divided to a jig unit zone, a molding zone for orientation molding and cooling to solidify, a jig removing zone, and a mold heating zone. In the heating zone, the heaters 7 are operated to previously heat the molding surface of the mold 8 before blow molding to a set mold temperature or higher to the crystal molding point or lower of the resin. Thus, parson can be pressed to the mold 8 so as not to lose the fluidity of the resin. |
