| 摘要 |
PROBLEM TO BE SOLVED: To provide a plastic bottle for pressure resistance, achieving both weight saving/easiness of crushing, and securement of hardness, through a completely unconventional approach.SOLUTION: A trunk 4 with a circular cross section includes a maximum diameter part 30, a recess part 32, a step part 34, a narrow part 36, and a maximum diameter part 38 sequentially in this order from the upper side. The recess part 32 has a whole circumference formed in a recessed shape in the radial direction, and a plurality of circumferential groove-shaped reinforcement ribs 70, 71, and 72. The narrow part 36 has a circumferential groove-shaped reinforcement rib 80. When the inside of the plastic bottle 1 becomes a positive pressure, the reinforcement ribs 70, 71, 72 and 80 are plastically deformed so as to make the groove depth shallow, and allow expansion of the recess part 32 and the narrow part 36 in the radial direction. |
