Packaging roll film is a kind of packaging form that buyers like very much now. Compared with ordinary packaging bags, it not only reduces the process of cutting and bag making, but also reduces the cost. Among them, there are two kinds of dealumination phenomenon in the composite film packaging: Black flake spots appear on the aluminum plated surface, and the aluminum coating disappears.
1. Flake black spots appear on the aluminized surface
The reason is that the vacuum aluminizing layer is very thin and easy to be oxidized in wet condition, so the flake black spots appear on the aluminized surface of the film.
2. The aluminum coating disappears

In particular, the packaging of pet aluminized film / PE film, and the tuyere edge of pet aluminized film / PE film composite packaging bag. This is because of the moisture or the middle by the adhesive solvent erosion, aluminum will disappear, in fact, is also a phenomenon of dealumination. When the internal stress of PE film is compressed and rebounded, the aluminum will transfer to the inner film, and then the aluminum will lose the support of the film mirror plane and disappear. If you look closely, actually a small amount of aluminum is still concentrated on the inner film.

countermeasure
1. the sealing edge of aluminum composite packaging bags must be pressed well. Note that the aluminum plated surface should not be bonded with PE film. The aluminum plated surface should be combined with the mask, then the aluminum plated film surface and the inner PE film will be combined.
2. Attention should be paid to the composite packaging bag with aluminum film, which should not be used as boiling and steaming bags.
Dongguan Beite packaging materials Co., Ltd. is a large-scale company specializing in the production of food grade composite packaging. It is a professional manufacturer of composite packaging bags. It uses new equipment to produce packaging bags and roll films, providing comprehensive, environmental protection and safety packaging services for the market.
The company produces composite bags, roll film, fruit bags, aluminum foil bags, suction mouth bags, self-supporting bags, zipper bags, anti-static bags, special-shaped bags, etc., which are suitable for the internal and external packaging of food, daily chemicals, electronics, toys, medicine, cosmetics, industrial products and other industries.
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