| 摘要 |
<p>PURPOSE:To secure self-standing stabilities and impact resistance strength by keeping the temperature of a region correspondent to the trough part of a self-standing bottle higher than the temperature of a region correspondent to the leg part thereof in potential heat in the circumferential direction of a preform in a time for biaxially stretching blow molding. CONSTITUTION:The neck part 42 of an injection molded preform 30 is held in a neck mold 40 and preferably conveyed to a temperature controlling stage. In the temperature controlling stage, temperature distribution becoming the proper temperature of stretching is given in a temperature controlling pot wherein the zone is divided in the longitudinal direction of the preform 30 having potential heat in a time for injection molding. At this time, even when a region 36 correspondent to the trough part of the preform 30 and a region 35 correspondent to the leg part thereof are temperature- controlled in the zone temperature controlling part set to the uniformly controlled temperature, the region 36 correspondent to the trough part has potential heat higher than the region 35 correspondent to the leg part because the region 36 is constituted of a thick-walled part 37. After the temperature controlling stage is finished, the preform 30 is conveyed to a blow molding stage by the mold 40. Thereby shaping properties in the leg part are made excellent.</p> |
