SYNTHETIC RESIN SQUARE HEAT-RESISTANT BOTTLE

摘要

PROBLEM TO BE SOLVED: To prevent occurrence of irregular deformation and to ensure a satisfactory stability on setting for a bottom part of a heat-resistant square bottle body made of synthetic resin by biaxially stretched blow molding with a heat resistance given by means of heat setting. SOLUTION: A grounding part 8 at the bottom part 7 of the heat-resistant square bottle body made of synthetic resin by biaxially stretched blow molding is constructed of flat wall part opposite grounding parts 9 each in a narrow planate grounding structure faceing each of flat wall parts 5 of a trunk part 4 and corner wall part opposite grounding parts 10 each in a linear grounding structure facing each of corner wall parts 6 of the trunk part 4, and thereby the amount of deformation by heat shrinkage at the flat wall part opposite grounding parts 9 and the amount of deformation by sink shrinkage at the time of releasing mold are made approximately the same with each other, ensuring a satisfactory stability for setting the bottle body.