Patent ID: 6730259
Filing Date: 2004-05-04
Classification: B29B,B29C,B29K,B29L

Abstract:
A method for stretch blow molding a wide-mouthed container, comprising the steps of: injection molding a preform having a large diameter mouth portion, a body portion and a bottom portion within an injection mold and wherein the body portion is formed in a conical shape in which the body portion is made thicker than the mouth portion and the diameter of the body portion is gradually decreased towards the bottom portion and the body portion is formed by gradually decreasing its wall thickness from a connecting portion towards the bottom portion; releasing the preform from the injection mold in a state where the inside thereof is still in a high temperature while holding the mouth portion of the preform which is cooled and solidified with a lip mold; transferring the preform to a blow mold as it is; and stretch blow molding the preform into a desired container, wherein before the stretch blow molding step of the preform a stretching rod is descended to a predetermined length to preliminary stretch the body portion to some extent, thereby thinning a wall thickness of the upper body portion, and after then the entire body portion is stretch blow molded.