摘要 |
The double blow molding process comprises a primary blow molding step of biaxially drawing and blow molding the preform into a primary intermediate product, a step of heating the primary intermediate product to shrink-mold it into the secondary intermediate product, and a secondary blow molding step of molding the secondary intermediate product into a bottle. This double blow molding process is characterized in that, just before the secondary blow molding step, the secondary intermediate product on standby is maintained at a temperature at least 40 DEG C or 50 DEG C higher than the mold temperature used in said secondary blow molding step. From such a temperature, it is possible to determine the double blow molding conditions, which can correspond to the levels of heat resistance required for the bottles, and to provide, with high productivity, the bottles having necessary levels of heat resistance. <IMAGE> |