01.10.05
Patented is a biaxially oriented polyester film with a base layer that is composed of at least 80% by weight of a thermoplastic polyester. The film has two outer layers A and C, wherein the outer layer A has high surface smoothness, Ra, ≤21 nm, and the outer layer C comprises external particles and has, per mm2 of film surface area, a number Nc of elevations whose respective heights h are correlated via the following equation: Ah1-Bh1·log10h/mm≤log10(NC/mm2)(1) 0.01 mm≤h≤1 mm Ah1=0.05; Bh1=3.3. The outer layer A comprises no external particles and the gloss (20°) of the uncoated surface layer A is greater than 190.