Two rolls of stretch film might look identical—until you use them. One feels smooth and clear; the other grips tighter and shrugs off punctures.
The difference lies in how they’re made.
Blown and cast films each bring unique strengths, and choosing the right one can have a major impact on wrapping consistency, cost, and machine performance.
How Blown Stretch Film Is Made
Blown film starts as molten resin pushed through a circular die, inflated into a tall bubble, then cooled and rolled.
This process builds a film with multi-directional strength and exceptional puncture resistance—ideal for heavy or irregular loads.
Pros: strong, tear-resistant, high holding force.
Cons: hazier appearance, louder unwind, less suited to high-speed machines.
How Cast Stretch Film Is Made
Cast film flows through a flat die onto a chilled roller, producing a smooth, transparent sheet with uniform thickness.
It unwinds quietly, offers great clarity, and works beautifully on most semi-automatic wrappers.
Pros: crystal-clear optics, consistent gauge, quiet application.
Cons: lower puncture resistance on sharp edges.
Choosing Between Blown and Cast Film
The best choice depends on your load type and wrapping conditions:
- Uniform loads with clean edges wrap best with cast film, giving smooth, quiet application and clear visibility.
- Mixed or uneven loads benefit from blown or hybrid films for stronger cling and puncture resistance.
- Heavy or irregular loads with rough surfaces perform best with blown film for maximum durability and hold.
Hybrid co-extruded films can blend both properties for balanced cost and performance.
Film and Machine: The Perfect Match
Even premium film won’t perform well on a poorly tuned wrapper.
That’s why every Nitech IPM machine includes programmable pre-stretch and film-force controls—so customers can get full value from any film type.
The Bottom Line
Blown film brings toughness; cast film brings clarity.
Choosing the right one isn’t about preference—it’s about matching film behavior to your loads and your wrapper’s capabilities.
Nitech IPM helps customers test and pair films for consistent, predictable results.