PLASTIC BOTTLE HAVING HANGER ON BOTTOM

摘要

PROBLEM TO BE SOLVED: To improve tensile and flexural strength of a hanger integrally formed on a bottom of a preform by thinning a coupling of the hanger by the drawing due to stretching for orientation. SOLUTION: A preform made of a crystalline resin and an annular hanger projecting from an outer bottom surface thereof are integrally formed by injection molding. A thin bottle is manufactured by blow-molding the preform. The hanger comprises an annular hanging portion and a thick coupling with such a quantity of heat that can be stretched after mold release. The coupling is drawn by stretching, thereby applying tensile and flexural strength to the hanger by orientation.