| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a cylindrical bottle that is formed of synthetic resin by biaxial orientation blow forming and has circumferential reinforcing grooves around the body to enhance the shape stability, by increasing the reinforcing strength of the circumferential reinforcing grooves to heighten the strength in vacuum and buckling. SOLUTION: A number of parallel circumferential reinforcing grooves 3 are provided around the circumference of a cylindrical body 2, and have upper and lower groove sidewalls 7 that expand outward at a slope and groove bottom walls 4 that are formed into a regular polygon column shape. In addition, the groove bottom walls 4 of the adjacent circumferential reinforcing grooves 3 that run parallel horizontally are in such a positional relation that a bottom wall ridgeline 6 of one of the groove bottom walls 4 is aligned with the middle of a flat wall part 5 of the other groove bottom wall 4. Therefore, reinforcing rib function is enhanced and deforming force is prevented from exerting unevenly so that high strength in vacuum and bucking is exhibited.</p> |
