Patent ID: 6528144
Filing Date: 2003-03-04
Classification: B29K,B32B,Y10T

Abstract:
A biaxially oriented, coextruded polyester film having a base layer B composed to an extent of at least 80% by weight of a thermoplastic polyester and one or more further layers, where at least one outer layer A contains internal and/or inert particles and where this outer layer has a number of elevations/protrusions N per mm2 of film surface area which is related to their respective heights h and diameters d by the following equationslog N/mm2hâˆ’Bh*log h/&mgr;m,â€ƒâ€ƒ(1) 0.01 &mgr;mAh=1.4; Bh=2.5 log N/mm2dâˆ’Bd*log d/&mgr;m,â€ƒâ€ƒ(2) 0.4 &mgr;mAd=3.4; Bd=2.4.