METHOD AND APPARATUS FOR UNIFORMLY STRETCHING THERMOPLASTIC FILM AND PRODUCTS PRODUCED THEREBY

摘要

Thermoplastic films and laminates (29) are made by extrusion and stretching using differential speed rollers (24, 27) employing a short stretching gap (x) of no more than one inch immediately after the extruded film product is formed. The method and apparatus (of Fig. 1) control the thickness of the stretched film and impart desirable mechanical properties thereto such as film products with a high modulus for handling and suitable tensile for softness. ® KIPO & WIPO 2007