Slip Agents

Slip agents are additives used to lower the coefficient of friction (COF) of a film surface. Common examples include the fatty amides oleamide and erucamide. Some slip additives move toward the film surface after extrusion, so the same roll may slide differently when it is fresh and after it has been stored.

If film drags on a forming collar, feeds unevenly, or is hard to unwind, measure film-to-film and film-to-metal friction under the conditions where the trouble occurs. Compare a fresh roll with an aged roll and record the storage time, temperature, and which side contacts the equipment. That comparison may reveal a migration-timing issue, but friction alone does not prove the additive is the cause. Gauge, winding, surface treatment, and machine setup can matter too.

Slip and anti-block are related but separate. Slip helps surfaces slide; anti-block additives help adjacent film layers release from each other. A film may need both properties balanced for the same converting line.

A fresh roll drags through a bagging machine while a roll from the same structure runs smoothly a few days later. Compare their measured friction and storage history before changing the slip formulation.

Adding more slip is not an automatic fix. A lower-friction surface may also change printing, lamination, or sealing behavior. Test the finished film on the intended equipment after any formulation change.

Slip is set when the film is made. We choose the slip level for the machine the film will run on and the time rolls will sit in storage first.

Tell us whether the film runs on a form fill seal machine, an automatic bagger or by hand. Tell us how long rolls usually wait before use. That is enough to set slip and anti-block together.