Food packaging bags Because of the inherent advantages and disadvantages of single-layer films, they cannot meet the requirements of more and more products and increasingly demanding food packaging bags. Therefore, two or more different properties must be used. The film or material is laminated to complement each other to meet the requirements of food packaging. This kind of bag made of food packaging materials made up of multiple layers of different materials is also called a composite bag. Food packaging generally requires packaging in a composite bag.