Aluminized composite film is a bright metallic film formed by evaporating high-purity aluminum wire into gaseous state at high temperature (1100~1200 ℃) through vacuum aluminizing process, and then when the plastic film passes through the vacuum evaporation chamber, the gaseous aluminum molecules precipitate onto the surface of the plastic film.

Aluminized composite film is a kind of composite soft packaging material formed by plating a thin layer of metal aluminum on the surface of plastic film by special process. The most commonly used processing method is vacuum aluminizing, which is to melt and evaporate the metal aluminum under high vacuum through high temperature, so that the aluminum vapor deposition is accumulated on the surface of plastic film, so that the surface of plastic film has metallic luster. Because it has the characteristics of both plastic film and metal, it is a cheap and beautiful packaging material with good performance and strong practicability.

At present, the most widely used aluminized films are polyester aluminized composite film (VMPET) and CPP aluminized composite film (VMCPP). The function of aluminum plating on the film surface is to block light and prevent ultraviolet radiation, which not only extends the shelf life of the content, but also improves the brightness of the film. It replaces aluminum foil to a certain extent, and also has low price, beautiful appearance and good barrier performance. Therefore, aluminum plating composite film is widely used in composite packaging. At present, it is mainly used in dry and puffed food packaging such as biscuits and the outer packaging of some medicine and cosmetics.