| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the weight of the neck part of a molding an improve the strength and the heat resistance of the neck part by blowing an injection-molded preform through stretching it over its entire area from the neck part so that the stretched blow molding has a small wall thickness. SOLUTION: A thread molding groove 6 or the like is engraved on the molding face of a neck mold 1. During molding of a preform, the molding face is concealed by an injection mold side to injection-mold the preform which is not threaded on the outer periphery of a neck. When blow-molding the preform by stretching into a container or the like, the molding face is made part of a cavity in the blow mold. The neck part of the container or the like is molded by the molding face and at the same time, a threaded part is formed on the outer periphery of the neck part using the thread molding groove 6 or the like.</p> |
