Patent ID: 6716386
Filing Date: 2004-04-06
Classification: B29B,B29C,B29K,B65D

Abstract:
A method of producing a bottle having a support ring in an outer periphery of a mouth portion thereof by biaxially stretch-blow-molding a pre-molded article for blow molding having the support ring and a barrel portion with bottom, whereinsaid pre-molded article is obtainable through the steps of: extruding a molten thermoplastic resin and cutting it into a mass of melt of nearly a predetermined amount; arranging a male metal mold and a female metal mold so as to move relative to each other and feeding the mass of melt into the metal mold; compression-molding the mass of melt into a pre-molded article while forming an and an annular groove in an inner peripheral edge in the lower surface of the support ring so that a change in the mass of the molten resin from the predetermined amount is absorbed as a change in height of the annular groove; and cooling and solidifying the compression-molded article and discharging the molded article out of the metal mold.