HIGH ORIENTATION BLOW-MOLDED VESSEL AND MANUFACTURE THEREOF

摘要

PURPOSE:To provide a vessel with high strength being composed of a thin vessel wall of uniform film thickness. CONSTITUTION:By substantially performing high orientation without any restriction, the vessel wall except a neck part or a neck part and a bottom central part is subjected to orientation-crystallization, to thereby render the film thickness of the vessel wall uniform, and the ratio of a film thickness of the thickest film part and the thinnest film part except the neck part is 1.0-2.0, furthermore, the degree of draw orientation-crystallization from the shoulder part to the neck part is made 20% or less. By this manner, the film thickness is uniform and thin, besides, the strength is large, thus preventing stress-cracking and neck bending.