BOPP/CPP composite film, also known as OPP/CPP composite film bag, is called: biaxially oriented polypropylene and unstretched polypropylene composite film bag. This composite film is the most transparent of all composite films. Compared with the single-film plastic bag, the cost is higher than that of the single-film plastic bag at the same thickness, but the hand feel is better than the single-film bag; and because the film has good moisture-proof performance, it is mainly used for packaging in food. Dry foods and fast foods such as biscuits, instant noodles, etc. The disadvantage is that it is resistant to high temperature and cold resistance, and it is not suitable to package refrigerated and high temperature sterilized foods.