Jelly and tofu sold at convenience stores, supermarkets, etc. Hold the lid of the cup and gently pull the edge to open and enjoy the food. The secret is not in the jelly container, but in the lid. The function of the lid is to prevent the contents inside from leaking, so the container and lid need to be heated and attached together. Although both containers and lids are made of plastic, there are many different raw materials for plastics with different properties. Therefore, it is important whether the container and the lid material “fit” when heat sealing. However, when I opened the lid of the jelly cup, I did not feel the existence of the easy-tear film. The lid of the jelly is made of an ultra-thin film with a thickness of 100 microns. The film looks like one layer, but it is actually 3 layers of film that are held together by an adhesive. The outermost base layer is used to print the trade name, the middle insulating layer is used to isolate oxygen and moisture to protect the things inside, and the innermost layer is the easy-tear film. The easy-tear film is only 50 microns thick, so it doesn’t seem unreasonable to go unnoticed. There are various kinds of foods that use easy-tear film, not only jelly and tofu, but also sterile rice, steamed egg custard, sliced ham and so on. After boxed instant noodles, plastic boxed foods such as jelly, pudding, and tofu became popular, and the demand for easy-to-tear films increased sharply. Constantly trying, mixing various materials, and improving the technology of extruding different materials to form films at the same time, an easy-to-tear film that can not only protect the Dongsi installed inside but also be easily opened was born. However, technology is constantly evolving with the changes of the times, and the improvement of products and the development of new products are never-ending. In today’s aging society, easy-to-tear films are faced with the challenge of opening with less force.