| 摘要 |
PURPOSE:To obtain a uniform thin-walled lightweight bottle by a method wherein a bottomed parison is inserted in a heating device, which has an inner surface shape slightly larger that the bottomed parison, and, after that, the bottomed parison is brought into contact with the heating device by being slightly inflated with a small amount of air blown in the parison in order to perform temperature control. CONSTITUTION:By injection-molding thermoplastic resin, a bottomed parison 1 is inserted in a heating device, which is made of molding the bottomed parson from metal blocks and the inner surface shape of which is slightly larger than the bottomed parison 1, and, after that, slightly inflated by blowing a small amount of air in the parison. As a result, the outside of the bottomed parison 1 is brought into totally contact with the inner surface of the heating device 3 made of metal blocks, resulting in heating the bottomed parison in a short time. By selecting metal with good thermal conductivity as the metal forming the blocks of the heating device and taking the circulating of heating medium into consideration, no temperature scattering develops over the contact surface of the heating device 3. The respective parts of the bottomed parison contacting the heating device turn to have same temperature, resulting in uniformly stretching the bottomed parison by blow molding and developing no ununiformity in thickness. |
