PURPOSE: To mold a container having an easy-to-break thin projection on the outer surface of the bottom section thereof by using the lower cintainer bottom die provided with the recess having no air discharge hole.
CONSTITUTION: Provided on the lower container bottom die 1a is a recess cylindrical, or inverse cone or inverse truncated cone shaped recess of which the ratio between the diameter of the mouth portion and the depth is 1 : 0.6W1.4, and the angle formed between the perpendicular line set up on the mouth edge outwardly with respect to the wall face of the lower die forming said recess and the side wall face is smaller than 45°, desirably 10W20°, and which has no air discharge port. The sheet softened by heating is placed into said recess by compressed air, and a projection with a tip thickness of 10W50μ is formed in said recess while the tip of thereof is kept apart from the bottom section said recess and air is kept between said recess and sheet.
WAKIGUCHI HIROYA
AKIYAMA KIMIO
ASHIKAWA MASAMI
