Containment force explained: holding power vs film thickness

Containment force is the inward pressure the wrap applies to the load — the force that turns a stack of separate cartons into one block that moves as a single mass. It is not a property of the film on its own. It is what the film, the tension, the number of revolutions and the wrap pattern produce together on that particular load.

In Toreto's wrap tests it is measured directly, with a gauge that reads how hard the wrap is holding the pallet, in kilograms per square inch. That is the number worth arguing about. Micron, roll price and metres on the roll are all proxies for it, and none of them predicts it reliably.

The clearest result in Toreto's own wrap tests of August 2026 is the one nobody expects. Solid film was run at 23µ, 20µ and 17µ on the same pallet, the same machine and the same 250% power stretch and tension settings. All three held the load at 9.9 kg/sq in. Identical containment across a third less thickness.

What the extra microns bought was weight: 200 g of plastic a pallet at 23µ, 174 g at 20µ and 140 g at 17µ, at roughly €0.48, €0.42 and €0.37 to wrap. Moving up the micron scale purchased material and cost in those tests, not stability. The costs are approximate and vary with film price and pallet size.

Because thickness is not irrelevant — it is simply not the variable that decides. 12µ nano film, run on its own at the same settings, held 7.6 kg/sq in. That is the lowest figure in the whole test, on 91 g and roughly €0.32 a pallet. Cheap to buy, and holding about a quarter less than the solid films above it.

Nano is a finely tuned film. It depends on a perfect machine and perfect settings, and when anything is off it fails easily, so in practice most users double-wrap it. That does hold the load — 11.9 kg/sq in, the highest reading in the test — but on 182 g and about €0.64 a pallet, at half the throughput.

From structure. Reinforced film carries banded reinforcement fused between layers, and those bands do not yield the way a plain film does: a lighter gauge behaves like a much heavier one. That is the design idea behind Supersonic, Toreto's reinforced “Tiger” film.

The row of the test that matters is the last one. Supersonic and Aerosonic at 16µ held 10 kg/sq in on 66 g of film at about €0.32 a pallet — more containment than 23µ solid, on a third of the plastic and at roughly half the revolutions, so the same wrapper produced twice as many pallets in a shift.

Aerosonic is the macroperforated version of the same material and performs the same, so a load that has to breathe can have containment and airflow at the same cost per pallet, on unchanged machine settings. Breathability usually costs holding power; here it does not.

Yes, and it is a real failure mode. Toreto's application guide puts it plainly: tension enough to secure the load fully, but not so much that the wrap crushes what is inside it. Over-tensioned film deforms carton corners, buckles the top layers of a light load and pulls bagged goods out of shape.

More turns is not more containment either. Once the load is held, additional revolutions mostly add film cost and machine time. With reinforced film the reinforcement carries the containment those extra revolutions would otherwise have to provide, which is why the guide is a single spiral up with 20–30 mm overlap, bookended by two revolutions at the base and two at the top.

Copy the test method. Take one representative pallet, run each film on the same machine at the same power stretch and tension settings, then weigh the film that went on and measure how hard the wrap is holding. Anything else — roll price, micron, metres per roll — compares the packaging, not the performance.

Then divide. Cost per pallet at equal containment is the number to buy on, and it has to include the revolutions, because revolutions are machine time and machine time is pallets per shift. In Toreto's tests two films landed on the same €0.32: one of them held 7.6 kg/sq in, the other 10.

Hand-wrapping operations can be measured the same way. In a field test in the United Kingdom in August 2026, the same difficult pallet was rewrapped by hand with the Hyper Wrap System: 181 g of conventional hand film became 151 g, two minutes became one, and 50% fewer metres went onto the load — £1.00 a pallet down to £0.74.