Stretch film basics

What is stretch film?

Written by Öncümak Engineering Team3 min read

What is stretch film?

In short

Stretch film is a thin, highly elastic plastic film, usually made from LLDPE, that is stretched around goods and holds them together as it tries to return to its original length. It keeps pallets stable, clean and tamper-evident during storage and transport.

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How stretch film works

Stretch film is applied under tension. As it is pulled around a load it elongates, and because it is elastic it keeps trying to contract. That recovery force, together with the film's cling (which makes the layers stick to each other), squeezes the load into one stable unit without tape, straps or glue.

A good stretch film balances three properties:

  • Stretch: how far the film can be elongated before it breaks.
  • Holding force: how strongly it keeps pulling the load together after it has been applied.
  • Puncture resistance: how well it survives sharp corners and edges.

What it is made of

Most stretch film is made from linear low-density polyethylene (LLDPE), sometimes blended with other polyethylene grades and small amounts of additives that give the film its cling. The film is produced on an extrusion line, either as cast or blown film, and wound onto large master rolls called jumbo rolls.

Where it is used

  • Securing pallets for warehousing and shipping
  • Bundling long or loose items such as profiles, pipes and boxes
  • Protecting goods from dust, moisture and tampering
  • Holding furniture and building materials together during transport

Food wrap is a different product: the thin cling film used in kitchens and supermarkets is usually PVC, not the polyethylene stretch film used on pallets.

Main types of stretch film

TypeApplied byWhat sets it apart
Hand stretch filmHand, with or without a dispenserSmall, light rolls: typically 50 cm wide, 2–3 kg and around 200–300 m
Machine stretch filmPallet wrapping machinesLarger, heavier rolls for automatic and semi-automatic wrappers
Pre-stretched filmHand or machineStretched during production, so less film is needed per pallet
Coreless filmHand or machineWound without a paper core; the whole roll is film
Slitted rollsHand or machineCut from a jumbo roll into narrower widths

The two most common formats are compared in hand vs machine stretch film.

From jumbo roll to the roll you buy

Film leaves the production line on jumbo rolls that are far too large for end users. Stretch film rewinding machines unwind these jumbo rolls and rewind the film onto smaller rolls in the length, weight and core size the market asks for. Depending on the machine they can also slit the film into narrower widths, pre-stretch it or wind it without a core. See what a stretch film rewinding machine is.

Advantages

  • Low cost per pallet
  • Keeps loads clean, dry and tamper-evident
  • Clear grades let you read labels through the film
  • Polyethylene film can be recycled where collection exists

Disadvantages

  • The wrong film, or the wrong stretch level, wastes material or leaves loads loose
  • Sharp edges can puncture the film unless they are protected
  • Used film has to be collected and recycled responsibly
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