Metallised Films, Properties and Uses

Metallised films are produced by the coating of polymer films such as OPP (Oriented Polypropene), PET(Polyethylene Terepthalate) and Nylon (Polyamide) with a thin layer of metal like aluminium.

Metallised films are produced by a process known as Physical Vapour Deposition. Although aluminium is the most common metal used for the deposition process, other metals like nickel or chromium can be used too.



The metallised film is of a glossy, silvery surface very similar to that of aluminium and gives the coated polymer a reduced permeability to light, water vapour and oxygen and at the same time still keeps vital properties such as high toughness, easily heat sealed and low density intact. The metallisation process reduces the Oxygen Transmission Rate (OTR) by about 50 times for OPP films and up to 10 times in PET films. In addition to that, metallised films have very good insulation properties and its reflective appearance improves a product's value aesthetically when printed on.

Although metallised films cannot match the barrier properties of aluminium foils, has more advantages such as:

• They are cheaper than aluminium foils.
• Unlike aluminium foils, there are no difficulties encountered during any printing or lamination processes such as tearing or creasing.
• Furthermore, foils are prone to cracking and pinholing when flexed. Hence, there is a high chance of compromising its barrier properties.
• Metallised films have a lower density and the film produced can be much more thinner than an aluminium foil.
• Foil laminations aren't recyclable.

Due to its above mentioned properties, metallised films have a range of uses.



Metallised plastic pouch for snacks

In the packaging industry metallised PET and OPP have started to replace foil laminates in products like snacks, dry powder pouches, oxygen-sensitive liquids (to some extent) and medical/pharmaceuticals. While metallised nylon and PE (Polyethylene) are used more widely in the meat export market. In addition to that, metallised films are also used as susceptors, that absorb electromagnetic energy normally from a microwave oven and convert that energy into heat.

Mylar Balloons

 



In decorations, metallised films due to their aesthetic properties are widely used in decorations such as Christmas tinsels and in items such as ribbons and wrappers. Metallised BoPET (Biaxially-oriented polyethylene terephthalate) films are used in the production metallic helium-filled balloons commonly known as Mylar balloons.

Due to its heat insulation properties and resistance to radiation, metallised PET films are used in NASA spacesuits as well as in proximity suits worn by fire-fighters. Metallised films are also used in the construction of insulated shipping containers, which are used for the shipping of temperature sensitive products such as food products or chemicals.



Antistatic Bag



Metallised films are also used in electronics. It's sometimes used as a dielectric for the prodction of capacitors and metallised PET is used in the manufacture of antistatic bags, which are used for the shipping of electronic components.