Metallised film

Metallised film is a plastic film, typically PET, BOPP or CPP, onto which an extremely thin layer of aluminium is evaporated under vacuum. The result looks metallic and transmits far less light, oxygen and moisture than the base film.

Why it is used

It is one of the most cost-effective ways to add barrier to a pouch. Blocking light slows rancidity in fatty foods, while lower oxygen and moisture transmission keeps snacks, nuts and coffee fresher. It also gives a silver base that can be overprinted with transparent inks for gold or copper effects.

Metallised film vs foil

Aluminium foil is a true metal layer measured in microns and offers a near-absolute barrier. The metal on metallised film is far thinner, so its barrier is good but not total. In return it is lighter, more flexible, less prone to flex cracking and usually cheaper. Most medium-to-high barrier food packs do well with metallised film; very sensitive or long shelf-life products still use foil.

Metallised layers sit inside a laminate rather than on the surface, are not microwave-safe and do not allow a clear product window.