Cling films are generally made of materials such as polyethylene (PE), polyvinyl chloride (PVC), and polyvinylidene chloride (PVDC). PE is relatively safe and is often used for packaging fresh fruits and vegetables and frozen foods without oil. PVC is often used to wrap vegetables and some agricultural products but is not suitable for packaging high-fat and cooked foods. PVDC has good barrier properties and is suitable for packaging meat, cooked food, and food that needs to prevent moisture evaporation.