What is blown film extrusion?

Blown film extrusion is a manufacturing process where melted plastic resin is forced through a circular die and inflated with air into a continuous bubble. As the bubble rises and cools, it is collapsed by rollers into flat film, which is then wound into rolls or converted into bags and pouches.

It is the primary process behind most flexible packaging film, including bags, liners, and rollstock used in food, industrial, agricultural, and retail packaging.