INCREMENTALLY STRETCHED FILMS WITH ENCHANCED PROPERTIES AND METHODS FOR MAKING THE SAME

摘要

Methods of enhancing one or more physical properties of a thermoplastic film include incrementally stretching thermoplastic films in the machine direction and/or transverse direction. In one or more implementations, methods of incrementally stretching thermoplastic films include reducing the gauge of the films without reducing the films' machine-direction tear resistance. The methods can involve cold stretching the films and imparting rib patterns into the film. The linear ribs can have alternating thick and thin gauges. Incrementally stretched thermoplastic films can have a machine-direction tear resistance that is approximately equal to or greater than the machine-direction tear resistance of the film prior to stretching.

主权项

1. An incrementally-stretched thermoplastic film with enhanced physical properties formed by stretching an un-stretched thermoplastic film, comprising:
a thermoplastic material; a ribbed pattern including thicker and thinner linear ribs extending across the incrementally-stretched thermoplastic film; a machine direction tear resistance that is approximately equal to or greater than a first machine direction tear resistance of the un-stretched thermoplastic film; and a gauge by weight that is approximately equal to or less than a first gauge by weight of the un-stretched thermoplastic film.