Cast and blown stretch film are the same polymer made two different ways. The price gap between them is real, and on most European pallets it buys a property nobody is using.
How they are made
Cast film is extruded onto a chilled roller and cooled fast. Blown film is extruded as a bubble and cooled in air, slowly.
That difference in cooling rate is where everything else comes from.
The four differences
1. Clarity
Cast is clear. Blown is hazy.
It matters more than it sounds. If your warehouse or your customer’s goods-in reads labels through the wrap — batch numbers, barcodes, hazard markings — hazy film means unwrapping to check, and unwrapping to check means rewrapping.
2. Noise
Cast is quiet off the roll. Blown is loud.
A wrapping station running blown film all shift is genuinely unpleasant to stand next to. It is not a specification issue and it is a real one.
3. Puncture and tear
Blown wins, and this is what the price buys.
Cast film punctures more easily, and once punctured a cast film tends to run. Blown resists the initial puncture and, more importantly, resists the tear that follows one.
This is the property that matters on sharp corners, on unstable stacks, and on anything handled four times between here and its destination.
4. Pre-stretch
Cast runs to higher pre-stretch more consistently.
Which matters commercially more than the rest of this article, because pre-stretch is where the money is. Film at 250% covers three and a half metres of pallet per metre off the roll; at 150% it covers two and a half.
So which
Cast for most palletised goods. Square loads, stable stacks, road freight inside Europe. Cheaper, quieter, clearer, and easier to run at the pre-stretch that saves you money.
Blown for the awkward ones. Sharp-cornered loads, unstable stacks, sea freight, and anything handled repeatedly.
If your loads are square and going by road, paying for blown is paying for a property you are not using — and if you are running blown because the loads keep shifting, the problem is more likely to be containment force than film type.
The test that costs nothing
Wrap a pallet. Try to move the top layer with your hand.
If it slides on the layer below, the load is not held, and no amount of blown film fixes a wrapper that is not applying enough force. If it does not move, the wrap is doing its job and the only question left is what it costs — which the cost per pallet calculator answers in about a minute.