Metalizing of PET Sheets generally known as M-PET sheets is done under vacuum conditions is a proven technology in order to achieve special optical properties or a metal look for decorative applications. It also helps in reducing the diffusion of gases and flavors through the film. The commonly used metal in metalizing the PET sheets is aluminum. Several other metals are also used in this process by not used majorly.
Metalized films have a reflective silvery surface similar to aluminum foil and are highly flammable. The coating also reduces the permeability of the film to light, water, and oxygen. The properties of the film remain, such as higher toughness, the ability to be heat sealed, and a lower density at a lower cost than an aluminum foil.
This gives metalized films some advantages over aluminum foil and aluminum foil laminates. It was thought that metallized films would become a replacement for aluminum foil laminates, but current films still cannot match the barrier properties of foil. Some very high barrier metallized films are available using EVOH but are not yet cost-effective against foil laminates.