| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve heat resistance and mechanical strength of a plug and improve recycling performance of an entire container by constituting at least an outer periphery of the plug of a polyester-based resin having a specific quantity of ethylene naphthalate units. SOLUTION: In this polyester container 10A, a support ring 3 is constituted by overlaying a first flange 3a made of a polyester resin 7 integrally provided with a container body 1 make of a polyester resin 7 mainly comprising polyethylene terephthalate resin on an upper part of the container body 1 on a second flange 3b made of a PEN-based resin 6 wherein at least 5mol% of repeated structural units have ethylene naphthalate units for coupling them. Thus heat resistance of the support ring is sufficiently secured by the second flange 3b made of the PEN-based resin, while resistance against capping pressure is secured by the first flange 3a made of the polyester resin.</p> |
