Metallized PET film in industrial applications - aluminium foil, blisters, laminates
Metallized PET film (metallized polyethylene terephthalate, PET-MET) is produced by coating polyester film with a very thin layer of metal. This is vapor-deposited in a high vacuum. The metal used is usually aluminum in its purest form (99.9 %). The use of aluminium optimizes the diffusion density. Vapor deposition with this metal creates a so-called barrier effect against foreign substances. This is a particular advantage over non-metallized plastic film.
In the industry, such films are also known as Mylar. These have a multi-layer structure and are flexible in terms of their properties. These films have very good insulating properties. At the same time, they are resistant to heat and cold and have a good surface hardness. The metallic sheen creates a special optical effect.
PET films
Metallized PET films essentially have the following properties. They are impact and abrasion resistant, difficult to tear and resistant to fats and oils. They also have a very attractive gloss, can be glued and are very suitable for direct contact with food.
PET-MET films
Metallized PET films (PET-MET) are used in a wide range of applications in industry, technology and everyday life. They are often found in the packaging sector. This preserves the freshness and aroma of the food. Metallized PET films are permeable to light and gas. This has a number of advantages over conventional aluminum foil. Aluminum foil is less suitable for salty, alkaline or acidic foods in particular, as it can release aluminum into the food.
As metallized polyester film has a metal layer, the electrical conductivity on the surface is altered. This is particularly useful for microwave dishes with a low water content. The food can therefore absorb more energy and heat up more quickly.
The tear resistance of the films is also higher. However, if high diffusion densities are required, aluminium foil is preferable, as metallized PET films are always slightly transparent.
The reflectance and also the optical density of metallized PET film increases with the thickness of the layer of aluminium vapour deposition. The more aluminum is used, the higher this is. The surface hardness also increases.
Metallized PET film is also used as a flame retardant and for rescue blankets. Thanks to their good insulating properties, the films are used for thermal insulation and against heat radiation in buildings.
