Aluminum foil is the most widely used metal foil for packaging. Aluminum foil is die cast from electrolytic aluminum or aluminum alloy plates with a purity of 99.3%. As a packaging material, aluminum foil film has many advantages, including light weight, which is conducive to reducing transportation costs. Aluminum foil composite film is a flexible packaging material, which is composed of aluminum foil and plastic film or thin paper. Common plastic films include polyethylene, polypropylene, polyethylene terephthalate (PET), polyvinylidene glycol, nylon, etc. The thickness of aluminum foil is 0.007 × 10000 9_ Or 0.012? 0.015mm, enough isolation effect has been obtained after compounding. According to statistics, aluminum foil composite thin_ 70% is used for food packaging, 17% for cigarette packaging, and 13% for drugs, detergents and cosmetics packaging. A typical application of aluminum foil composite film is to make a soft container a cooking bag (called soft can). PET film provides excellent Engraving resistance; Middle layer brocade_ It is the most economical moisture-proof, oxygen proof and light proof microbial material, and also the key to maintain the stable shelf life of cooking bags; The polymerization period of the inner layer has excellent heat sealing property. Therefore, the cooking bag has the advantages of light weight, low energy consumption, no need to refrigerate and transport the aluminum foil composite film, and can also be used as a trademark material, with good decoration effect. Metal and glass cans, frozen food.