| 摘要 |
<p>PURPOSE:To secure the strength of the neck part of a vessel as well as the multi-layer property of an expanded part by a method wherein one end of a pipe is expanded into the shape of a tranpet and the neck part, connected to the end of the pipe, is made separately by the injection molding of thermoplastic polyester while both of them are integrated by fusion welding. CONSTITUTION:An intermediate body, having the cylindrical part 6 and the bottom part 7 of a co-extrusion multi-layer pipe consisting of an intermediate gas barrier layer made of the copolymer of ethylene vinyl alcohol and inner and outer layers made of polyester, is formed. The open end of the intermediate body is expanded with a male mold 14 so as to coincide with the diameter of a final product or a neck part substantially while resin, such as polyethylene phthalate or the like, for forming the neck part is injected through runners 17, 19 to connect it to the expanded part. This preform 21 is heated preliminarily to the proper temperature of orientation, and it thereafter formed by blow forming into the final product. According to this method, a PET bottle excellent in gas barrier property can be obtained.</p> |
