| 摘要 |
PROBLEM TO BE SOLVED: To provide a cap to be used for a container subjected to retort sterilization, and including a liner excelling in dropping sealability in addition to openability and sealability.SOLUTION: The cap is formed by using, as a material, a composition having a reovery of 60% after compression of 70% or higher at 130°C, and an elongation of 100% or higher at 130°C, respectively, out of compositions having high elongation described in the patent publication No.4319594. In the cap, the thickness of a flat part 7b is 80-150% of the circumferential radius r of a curl part 8, the projecting length L4 of the flat part is 0-65% of the radius r of the curl part, and the compression amount of the flat part 7b is 60-90%. An outer peripheral surface 7co of an inner rib 7c is tapered at 15-45°. The thickness L1 of a root part of the inner rib 7c is 50-150% of the radius r of the curl part. The length L2 of the inner rib is 60-150% of the radius r of the curl part. |
