Stretch film
Stretch film is the umbrella term for elastic films that are extremely stretchable without tearing; When stretched below their elastic limit , these films have a high restoring force . If the films still adhere well to one another even after they have been stretched to a great extent, they are called adhesive films .
Cling film
In the supermarket they are used to pack meat and vegetables in trays and bowls. In the home, cling film is used to cover bowls and to wrap food.
Due to their polarity, PVC-based cling films have the advantage that the formation of drops is avoided and condensation does not form on the film. This anti-fog property of the film is very much appreciated in the supermarket , as otherwise the packaging unit can become unsightly due to water misting (drops).
Cling film is also made on the basis of polyethylene . PE as a non-polar plastic has no anti-fog properties.
Silage film
Animal feeds preserved with silage film or "agricultural stretch film" are fermented by lactic acid fermentation . The good elasticity and adhesive strength of the film allow the silage to be packaged airtight, which is crucial . The film thickness is 25 µm, the roll widths are 500 mm or 750 mm, depending on the silage stretch machine used .
Load unit securing film
Stretch films for securing load units enable dimensionally stable load securing by palletized load units (e.g. cardboard boxes, sacks, boxes, barrels):
- Establish a firm connection, a frictional connection, between the pallet base and the goods on the transport pallet .
- also prevent the individual layers / layers of the goods from moving and shifting among each other.
- Protection against external mechanical and climatic loads and ease of handling.
Packaging stretch films are produced in a wide variety of thicknesses and widths. Foil thicknesses between 12 and 35 µm with a roll width of 500 mm are typical.
Depending on the daily pallet volume, the pallet is secured manually with hand stretch film or by machine with machine stretch film with wrapping machines (= stretch wrappers, stretch machines, stretch systems). Rolls weighing a maximum of 20 kg are used, which are processed on semi and fully automatic stretch systems. In the beverage industry, fully automatic stretch systems are usually an integral part of the filling system. Stretch wrappers are available in a wide variety of designs and price classes, semi-automatic to fully automatic, for horizontal and vertical pallet wrapping, the specialist speaks of "stretching". Stretch film in roll widths of 100 - 250 mm is used to bundle long transport goods.
Perforated (macro-perforated) stretch film is used to secure pallets that require air circulation (plants, cardboard boxes that still have to dry out, canned food sterilized in the autoclave).
A rather exotic application is the area of bondage , but also the protection of suitcases at airports.
With an annual consumption of 1.5 million tonnes in Europe, stretch film is a mass product of the European film industry, with a significant share in the total LLDPE consumption.
Hood stretch film
Stretch hoods also stretch hoods come in uniform sized loading units (z. B. pallets with refrigerators, bricks, etc.) are used. They are pulled by grippers over the load and the pallet base, where after being released they are firmly attached to the load and the pallet, thus securing the load unit.
