| 摘要 |
<p>PURPOSE:To retain transparency of the body of a polyester bottle and increase the crystallization speed of the neck by making at least part of the neck a multilayer structure having an easy crystallization layer on its outside and the other parts a multilayer structure having a polyester layer on its outside. CONSTITUTION:A multilayer preliminarily molded product consists of a neck 1 and a body 2. The neck 1 has threads 3, a locking ring 4 and a support ring 5 and comprises an easy crystallization polyester layer 11, a polyester layer 12, an easy crystallization polyester layer 13, a polyester layer 14 and an easy polyester layer 15, in this order from the outside. An opening end 16 is wholly covered with an easy crystallization layer. On the other hand, the body 2 has a structure having a thin easy crystallization layer 19 sandwiched between polyester layers 17 and 18, and the thickness of the easy polyester layer 19 at the body 2 is 5% or less of the thickness of the wall of the body 2. When the thickness of the easy crystallization polyester layer 19 is 5% or more of that of the body, transparent feeling of the body becomes not sufficient and is not desirable.</p> |
