| 摘要 |
<p>PURPOSE:To enable the production of bottles being excellent in a thermal stability by a simple operation, by a method wherein a bottomed parison, in which a maximum thickness, an average thickness of a shoulder portion, and a minimum thickness of a bottom are set to a given value, is stretched according to a given stretching magnification, and then fixed by heat. CONSTITUTION:A bottomed parison 1, in which a thickness T of a thickest portion, an average thickness t1 of a portion, becoming a bottle shoulder when molded into a bottle, and a minimum thickness t2 of a portion, becoming a bottom when molded into a bottle, satisfy an inequality I, is injection-molded. The parison is blown into a bottle at a suitable stretching temperature and under a stretching condition of an average magnification gamma in an axial direction and an average circumferential magnification beta which satisfy an inequality II, and is then fixed by heat to produce a polyester bottle 2. A copolymer or the like having 70% or more of a polyethylene terephthalate or an ethylene terephthalate unit can be used as polyester for the production of the bottle.</p> |
