Cast vs Blown Stretch Film: How to Choose the Right Film

How the two are made

Cast film is extruded through a flat die and cooled on rollers. It tends to have consistent thickness and good clarity.

Blown film is extruded as a bubble and then collapsed. This process can produce films with good toughness and puncture resistance, and the performance depends on the resin and process used.

What to compare on your loads

Factor	Cast film	Blown film
Thickness consistency	Generally very consistent	Varies more by grade
Clarity	Generally clear	Varies
Machine behavior	Often steady under pre-stretch	Depends on the grade
Puncture and tear resistance	Depends on grade	Often strong for its gauge
Best fit	Consistent machine wrapping	Rough or sharp-cornered loads

How to test it

Pick three representative loads, including one with sharp corners or protruding items.
Wrap each load with the candidate film at the same machine settings.
Check containment, tears, holes and film use after the same handling you see on your dock.
Compare the cost per load, including any damage, not the price per roll alone.

Ask your film supplier for a sample and the technical data sheet, and confirm the maximum pre-stretch the film holds before you commit to a full order.

Common questions

Which film is stronger, cast or blown?

It depends on the grade. Blown film is often chosen for toughness, but many cast films perform well. Compare data sheets and test the film.

Which film works better on a machine?

Cast film is often used for machine wrapping because it is consistent, but the best film is the one that holds containment with your machine settings.

Does the film type change how much film I use?

It can, through its maximum pre-stretch and gauge. Test the setting before you change your film order.