| 摘要 |
PURPOSE:To obtain a biaxial stretch bottle having annular raised streak or bellows by molding a port die and a lower end of a cavity face with biaxial stretch blow molding using a barrel die having a step whose lower diameter is expanded and a bottom die slidable in the enlarged diameter, and pressing an expanded part formed with the step by the bottom die and folding it. CONSTITUTION:A blow molding die comprises a port die 21, a barrel die 22, and a bottom die 23. The barrel die 22 has a cavity face 22a having a shape ranging from a lower end of a port of a bottle to almost the center of the, barrel and a step 22b in the neighborhood of the central part. An inner peripheral face 22c at a further lower part forms a face which slides together with the outer peripheral face of the bottom die 23. The bottom die 23 is positioned on the lower part and a cylindrical parison having a bottom is held at the port die 21, so as to perform biaxial stretching blow molding. In a space between the step 22b and the bottom die 23, a raised streak 11a is formed. Before a molded body is cooled, the bottom die 23 is pushed upward and the raised streak 11a is folded. Thus, a bellows 11b can be formed. |
