| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a pressure-proof polyester bottle having a self-standing type structure in which foot segments and valley segments are alternatively installed therein and some contents producing self-generative pressure are filled, and bottom cracking and latent bottom cracking are prevented from being produced even in a long-period storage under a high temperature and high humidity condition. SOLUTION: There is provided a pressure-proof polyester bottle in which foot segments and valley segments are alternatively arranged at its bottom segment 4, the valleys have a curved surface with a substantial uniform radius of curvature in a height direction, density of the valley within a radius corresponding to 40% of a radius of barrel from the center of the bottom segment is lower than 1.34 g/cm3 and the valleys have no substantial single-axial orientation in a circumferential direction.</p> |
