PROCESS TO INJECTION-MOLD A POLYESTER RESIN PREFORM, AN INJECTION SCREW AND PROCESS TO MOLD THE SAME BY DRAWING AND BY BLOWING.

摘要

The present invention explains how when a desired preform is going to be molded from a molding material, which is a polyester resin formed from a PET and PEN mixture by molding material compression and fusion by a screw rotation in a heating cylinder and injecting and filling melted material in a molding, a plastification zone 13 for molding material is formed in an injection screw 2 compression zone 12 and a measuring zone 14 in a screw end. In plastification zone 13, molding material is submitted to fusion, relaxation, mixing and relaxation to melt and to eliminate a non melted material until melted material reaches dosing zone 14. To avoid that a molding article becomes opaque and a non melted granular material production, gel like, a polyester resin composed of a PET and PEN mixture is utilized as a molding material.