| 摘要 |
PURPOSE:To tear a plastic lid easily along the low strength part, and at the same time, prevent fingers from being cut by the edge after the tearing by a method wherein the low strength part with a ring shape is provided on the plastic lid, and at the same time, a part of the lid material along the low strength part is crystallized. CONSTITUTION:A plastic lid 1 is formed of a bottom part 2 which consists of a flat surface to cover the opening of a container, and a flange part 3 to correspond with the flange part of the container 13. Also, on the bottom part 2, a low strength part (thin part) 4 with a ring shape and a pull part 5 which is located inside of the low strength part 4 are provided. In addition, on the lower surface part A of the flange part 3, an adhesive is applied, and at the same time, a part B of the lid material along the low strength part 2 is crystallized. The flange part 3 of the plastic lid 1 is joined to the flange part of the container by the adhesive layer. By this method, when the pull part 5 is pulled up by a finger, the plastic lid 1 can be easily torn along the low strength part 2. |
