| 摘要 |
PROBLEM TO BE SOLVED: To provide a blow molding method which can secure the strength of a blow molded object by securing a sufficient wall thickness which is required for the blow molded object even if the blow molded object is made light in weight by modifying existing facilities slightly.SOLUTION: First, after assembling a preform heated at a blow molding temperature into a blow molding die, the die is closed and a cooling medium is sprayed to a special region of the preform showing a blow molding temperature from an air plenum formed in the die. Next, a specified temperature difference ΔT is set at a specified region by cooling the specified region rather than the temperature level of the other region, and thereafter, the preform is blow-molded into a resin-made container with a handle as a molded object. Furthermore, a position at which the cooling medium is sprayed can be set to coincide with a position where the specified region in the molded resin-made container with a handle, is preset, and thus, the preset wall thickness of the specified region can be obtained. Thus, a necessary spot can secure a sufficiently thick wall and its strength even in the case that the blow-molded object is successfully made light in weight by slightly a modifying the existing facilities. |
