PACKAGING CONTAINER EQUIPPED WITH SPIRAL VACUUM SUCTION PANEL

PROBLEM TO BE SOLVED: To provide a spiral plastic bottle equipped with a plurality of spiral panels thereon in the circumferential direction capable of dispersing stress exerted during vacuum suction, and effectively preventing the depression and buckling of a pillar by reinforcing the strength of a part at concentrated pressure so as not to deteriorate a vacuum suction function. SOLUTION: In the spiral plastic bottle, a pillar of a spiral panel has a shape which is narrowest in the vicinity of the center, and continuously expanded toward top and bottom sides, and a boundary between upper and lower annular parts and a spiral panel body has a substantially regular polygonal shape which is sectioned by an arc-shaped diagonal plane with the panel width substantially equal to the pillar width. The curvature of the cross section of the vacuum suction panel is maximum in the center, and smaller toward the top and bottom sides to reduce a difference in the depth of the spiral panel. COPYRIGHT: (C)2010,JPO&INPIT