How is plastic film different from a plastic sheet?
Plastic film is a continuous polymeric substance that is very thin and flexible. "Sheet" refers to a thicker plastic substance. By convention, manufacturing of plastic film is called "converting" while manufacturing of plastic sheet is called "extrusion". These thin plastic membranes are used to divide spaces or volumes, retain things, function as barriers, and provide printed surfaces. Simple monolayer plastic films are used for a number of purposes including plastic shopping bags, labels for other packages, in building and construction, for landscaping, and other categories. Multi-layer films, such as a traditional 5 layer structure, are widely used in food packaging where oxygen and water transmission rates are a critical component of package performance.