METHOD OF FORMING HEAD PART OF CLOSED TYPE TUBE, PROCESS FOR PRODUCING CLOSED TYPE TUBE, AND CLOSED TYPE TUBE CONTAINER

摘要

It is intended to provide a tube container capable of preventing falling of a closing material at the time of opening by forming a mouth head part with the utilization of stress at pressurized charging of a molten resin according to compression technique while avoiding the step of forming a projecting portion on a convex-part circumferential surface of closing material. A mouth head part fitted with closing material (22) is produced by fitting projecting locking part (21) provided at a distal end of mandrel (20) with cup-shaped closing material (22) with a spacing between the closing material (22) and the front edge of the mandrel locking part; thereafter while arranging molten resin (26) in cavity (25) of molding die, bringing the same into pressurized contact with a convex-part front edge surface of the closing material so as to effect folding of the front edge surface of the closing material (22), thereby forming ringed corner part (30) on the circumferential circular region thereof; and while charging under pressure the molten resin (26) into the cavity (25), causing the molten resin (26) to surround the ringed corner part (30).