POLYESTER CONTAINER REFILLED AND PREFORM FOR FORMATION OF CONTAINER

摘要

PURPOSE: To provide a refillable polyester container having a bottom structure showing a resisting force against a strain crack. CONSTITUTION: This container has a dome-shaped base structure. In such a dome-shaped base structure, its wall thickness is increased gradually and smoothly in such a way that it may become a maximum value at a central part of the dome. Such a container as above is formed by blow molding a perform having a special form of the present invention. The container and a blow die cavity especially designed to have a blow formation to receive an extended gate-like lower axial protrusion without being crushed or damaged.