Aluminum foil bag and composite bag are two kinds of packaging bags which are widely used at present, and they both occupy a certain market position at present. Their similar appearance makes it difficult to distinguish aluminum foil bags from composite bags.
　　Well, this article will answer their differences.

　　First, let's take a look at what are aluminum foil bags and composite bags:
　　(1) Aluminum foil bag, as the name suggests, is a kind of packaging bag containing aluminum foil, which is the finished product of our common aluminum foil bag after dry mixing with aluminum and high barrier materials.
　　(2) Composite bag, outer printable film (BOPA biaxially stretched polyester BOPP), inner heat sealable film (chlorinated polyethylene) and coextrusion film. Al (aluminum foil) is also one of them, usually as an intermediate layer. These materials are compounded into composite films with glue as required.
　　So how can we quickly distinguish between aluminum foil bags and composite bags?
　　The first is the difference in appearance: generally, aluminum foil packages have metallic luster, and have strong reflection ability through the sun. The color printed on aluminum foil packages looks more beautiful.
　　2、 Difference of insulation performance: aluminum foil package is famous for its strong insulation and good protection. Its air tightness and water vapor characteristics can effectively prevent the items in the package, making it more convenient and easier to store.
　　The third difference in packaging: the current aluminum foil package can leave transparent parts at any position on the package, so that customers can see the contents clearly and intuitively.
　　The composite bag is suitable for vacuum packaging or general packaging of food, electronic products, chemical, pharmaceutical, tea and national defense products. The process includes three sides: edge sealing, back sealing, middle sealing and sealing. Four different machines are required. The "composite bag" has good heat preservation performance, strong protection performance, and is airtight and water vapor free. Therefore, the plastic sealing function can effectively prevent moisture absorption and vaporization of the contents, is not easy to be invaded by bacteria and insects, has good shape stability, and is not affected by humidity changes.
　　These are aluminum foil bags and composite bags. I hope my analysis is helpful to you.