Stretch film basics

Stretch film vs shrink film: what is the difference?

Written by Öncümak Engineering Team3 min read

Stretch film vs shrink film: what is the difference?

In short

Stretch film is applied cold: it is stretched around the load and holds it as it tries to contract. Shrink film is applied loose and then heated, so that it shrinks tightly around the product. Stretch film is the usual choice for pallets; shrink film is used for retail packs and for some pallet loads such as bricks, where it is applied as a hood and heated.

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The short answer

Both are plastic films that hold goods together, and both names are often mixed up. The difference is how they get tight:

  • Stretch film is stretched as it is applied. It is elastic, so it keeps trying to contract and squeezes the load together. No heat is used.
  • Shrink film is put on loosely and then heated. The heat makes it shrink and close tightly around the product.

How stretch film works

Stretch film is a thin, elastic polyethylene film. The European Commission's cargo securing guidelines (2014) describe it as very thin film of 10 to 30 microns, mostly on rolls 50 cm wide. It is wrapped around the load by hand or by a pallet wrapping machine; the machine stretches the film first between two rollers and then again between the roller and the load. The tension in the film and its cling hold the load together. See what stretch film is.

How shrink film works

Shrink film is stretched while it is still warm during production and then cooled, which locks the stretch in. When it is heated again, it shrinks back toward its original size. Patents describe heat-shrinkable films made of polyvinyl chloride (PVC), oriented polypropylene and polyethylene.

To apply it, the film is placed loosely around the product, as a sleeve (hood) pulled over a pallet or as flat film, and then heated. Retail packages are passed through a heat tunnel; on pallets, the EU guidelines note that the film is heated mostly with hot air, and that it can even be shrunk with a simple gas burner.

Where each one is used

  • Stretch film: securing pallets for storage and transport, and bundling long or loose items.
  • Shrink film: retail packages, sealed in film and passed through a heat tunnel (Lantech, a maker of pallet wrappers, gives a candle or a video game box as examples), and some pallet loads. The EU guidelines name bricks and some bagged fertilisers as typical examples.

Side by side

Stretch filmShrink film
How it gets tightStretched while applied, then contractsApplied loose, then shrinks when heated
Heat neededNoYes: heat tunnel, heat gun or gas burner
ThicknessVery thin (10–30 µm on pallets)Described by the EU guidelines as "rather thick"
Applied byHand or pallet wrapping machineHeat tunnel; on pallets, a hood or flat film plus a heat source
Typical usePallets and bundlesRetail packs; pallets of bricks or bagged goods

Cost and safety

The EU guidelines say that shrink film, when properly applied, can be very effective at holding a pallet together, and that it can be applied by hand. They also report that its use in Europe is decreasing, mainly because of its relatively high cost and the risk of fire during application. Stretch film needs no heat at all.

A third option: stretch hoods

A stretch hood is a film sleeve, smaller than the load, that a machine stretches and pulls over the pallet; it then contracts around it, without heat. The EU guidelines list high-speed automatic application, very good weather protection and a lower cost than shrink hoods as its main advantages, and note that each load size needs its own hood size.

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