| 摘要 |
PURPOSE:To mold the blow molded container concerned with no thickness ununiformity by a method wherein parison is drafted at a speed, which is higher than the speed of travel of the tip of the parison, under the condition that the temperature of the parison is higher than the melting point of resin after the parison in the form of molten tubular resinous body is extruded from the tip of a die and, after that, pressurized fluid is forced in the parison. CONSTITUTION:Firstly, molten thermoplastic resin is extruded from the tip of a die 2 in the form of parison 1. The parison 1 is drafted at a speed, which is higher than the speed of travel of the tip of the parison 1 or the drawdown speed of the parison 1, with a stretching device, to which a chuck 5 is fixed. Further, with or after the drafting, the parison 1 is cut off from the die 2 at the position, which is the connection between the parison 1 and the molten resin in the die 2 as indicated with the arrow 6 and to which the tip 4 of a driving device is connected so as to force pressurized fluid such as air or the like in the prison 1. On the other hand, a mold 3 is arranged outside the parison so as to form the outer wall of the parison, which is expanded by the pressurized fluid 7, with the mold 3 into a blow molded body. |
