A range of biaxially drawn films made from polyethelene terephthalate polymer, created by extruding the polymer through a slot die, then drawing it in two directions at right angles to orient the molecules in the plane of the film, then held under tension and heat set. Polyester film has great strength, dimensional stability, and resistance to chemicals, and has been used in a variety of industrial applications, as a base for motion picture film, videotape, and audio tape, and archival housing for documents, laminate, and many other uses.
