The presentation of PET film materials has made food packaging develop rapidly. It was the first time to use PET bottles to package cool drinks. Food and beverages packaged in PET containers have gradually become "hot cakes". The light weight and robustness of PET containers attract customers and are expected by shopping malls. PET materials also have the advantage of being able to form any shape (good applicability), being able to be processed into colors that suit everyone's hobby, and being able to print words and pictures; With excellent strength and dimensional stability, cold resistance and chemical stability, it is widely used in composite packaging, photographic film, metal evaporation, audio and video recording and other substrates.