Solution to dealumination phenomenon of aluminized composite film

Packaging roll film is a packaging form that buyers like very much now. Compared with ordinary packaging bags, it not only reduces the cutting and bag making procedures, but also reduces the cost. Among them, there are two kinds of dealumination phenomena of aluminum-plated composite film packaging: flake black spots appear on the aluminum-plated surface, and the aluminum-plated layer disappears.

1. Flaky black spots appear on the aluminized surface

This is because the vacuum aluminized layer is very thin and easy to be oxidized when wet, resulting in flake black spots appearing on the aluminized surface of the film.

2. The aluminized layer disappears

Especially the packaging of PET aluminized film/PE film, and the sealing edge of PET aluminized film/PE film composite packaging bag. This is because moisture or the middle of the adhesive is dissolved and corroded, which will also cause the composite film to open. When the internal stress of the blown PE film shrinks and rebounds, the aluminum transfers to the inner film, and the aluminum loses the mirror plane of the film. Relying on, also disappeared as if disappeared. If you look closely, in fact, a small amount of metallic aluminum is still concentrated on the inner film.

Countermeasure

1. The sealing edge of the aluminum-plated composite packaging bag must be pressed well. Note that the aluminum-plated surface should not be bonded to the PE film. The aluminum-plated surface should be composited with the film, and then the aluminized film surface and the inner PE film should be composited.

2. Pay attention to the composite packaging bag with aluminized film, it is not suitable for boiled and retorted packaging.