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First, watch, second, feel, third, fold, fourth, twist and twist, fifth, knife scrape, sixth, fire method to help you distinguish plastic composite packaging is made of aluminum foil or aluminized film material.

2. Watch: The brightness of the packaging aluminium layer is not as bright as that of the aluminium-plated film. That is to say, the packaging made of aluminium foil is not as bright as that made of the aluminium-plated film. Aluminum foil is thick and has strong light shielding. Aluminum coating is very thin and has poor light shielding. Therefore, it can pass through the strong light by using aluminium-coated film, whereas the poor light transmission is made by aluminium foil. Because of the brightness of aluminized film, the reflectivity of aluminium foil is not as good as that of aluminized film, but the refractive and shielding properties of aluminium foil are better than that of aluminized film. Aluminum foil packaging is silver-white or silver-gray, and aluminized film packaging is silver-yellow or silver-black.

3. Hand feeling: Aluminum foil packaging feels thicker and stiffer, heavier. Aluminum film packaging feels lighter and softer than aluminum foil packaging.

Fourth, folding: Aluminum foil packaging is easy to fold into dead fold mark. Aluminum-plated packaging will not fold into dead fold mark, and will soon rebound.

5. Twisting: The coalescence of aluminum foil packaging is not easy to rebound after twisting, and the aluminium layer will break. The wrapping of aluminized film will spray out quickly after twisting, and there will be no obvious cracks in the aluminium layer.

6. Knife Scraping: Aluminum foil can be scraped off with a knife, then the aluminized film will not scrape off the aluminium chip, but will shine on the film.

7. Fire: Aluminum foil is not easy to burn with fire point. Aluminum layer will roll back. After burning, the packaging of aluminium foil will leave gray aluminium slag. There are no residues of aluminium slag in the burning process of aluminized film.