As the name implies, the aluminum washing process, also called as demetallizing process, it is a technical upgrade of ordinary printed packaging film and anti-counterfeit film for the cleaning and partial hollowing of metalized film to achieve more colorful printed film and anti-counterfeit packaging film. Usually in order to get better barrier degree of the film, it will make metalizing treatment for film
Definition：
Compared with ordinary film printing and metalized film printing, the latter has a better printing effect and can highlight the colorfulness of the ink (some moisture-proof and sun-proof products should use aluminized film), which is more beautiful for packaging products, just like the difference between mirror and glass. But ordinary aluminized packaging bags and can not let consumers clearly see the products inside, the yin and yang aluminized packaging bags aesthetics and practicality and can not fully achieve the effect. So the birth of aluminized film washing process, this process allows the packaging film to leave any desired pattern text, while any unwanted windows and graphics can be hollowed out and washed away. This process technology not only retains the color of intaglio printing, but also can see the products inside the package, and can improve the anti-counterfeiting technology of the packaging film, and some products can also wash out special patterns to transfer to paper packaging to play the role of anti-counterfeiting.
Principle：
Aluminum washing process is mainly divided into two kinds: one is alkali washing (chemical washing), and one is water washing (ordinary tap water). Alkali washing process: aluminized film (pet, opp, pvc, cpp) → surface printing (generally gravure printing) → aluminum washing (best to play the base color, and printing ink shall not be too thin). Washing process: ordinary transparent film (pet, opp) → lithography (gravure printing) → aluminizing (vacuum metalizing) → washing aluminum (printing the last two colors to be on the protective oil and wash ink).
Process characteristics：
Alkali washing is characterized by fast production speed, easier process, easy procurement of raw materials, but quality control is more difficult to control, the shortcoming is that once the color printing too much then overprinting a bit trouble, lamination strength is not good, alkali pollution of the environment, sewage must be treated before discharge. Water washing is characterized by more production processes, quality control is easy to grasp, better quality aluminum washing, compound strength is much better than alkali washing, no other chemical residues easy to pass the certification, aluminum washing discharge water pollution is smaller, but also need to be treated before discharge.
However, this needs to be based on the actual production needs to determine which process is more suitable for their products. So the demetallizing machine quality and technology is one of key important factors.
Applications：
Aluminum wash packaging film is widely used in a series of products such as flexible packaging bags, anti-counterfeit labels, laser packaging film, aluminum wash composite film, thermal transfer film, anti-counterfeit transfer film, water labels, etc. for food, electronic products, clothing, tobacco, cosmetics, pharmaceuticals, mineral water, etc.
In addition, aluminum wash process is also applied to aluminum foil (PET+Al foil), which is needed in special electronic products or application scenarios.
