METHOD OF REHEATING POLYESTER PREFORM FOR BLOW MOLDING

摘要

A hybrid reheating of polyester preforms which are to be stretch blown into containers wherein the reheating coupled with the controlled quick initiation of the blow stretch operation after final reheating produces a container which may be filled with a hot fill without there being any disadvantageous shrinkage of the container. The reheating is by way of a specific combination of quartz oven reheating and radio frequency reheating together with specific equilibrations of the temperature cross sectionally of the preform body. Polyester preforms may be reheated to a cross sectional center temperature ranging from 225 DEG F to 260 DEG F and stretch blow molded without undesirable surface crystallization occuring while the ability of the container to be filled with a hot fill substantially without shrinkage is increased.