Patent ID: 7144615

Claim:
Coextruded, transparent, biaxially oriented polyester film comprising a base layer (B) and a heatsealable top layer (A) which is peelable with respect to at least CPET, the heatsealable and peelable top layer (A) consisting of a) 70–97% by weight of polyester and b) 3–20% by weight of a polyester-incompatible polymer or anti-PET polymer based on the mass of the top layer (A) and c) particles, wherein d) the polyester used to form said top layer (A) is composed of 20–95 mol % of units derived from at least one aromatic dicarboxylic acid and 5–80 mol % of units derived from at least one aliphatic dicarboxylic acid, the sum of the dicarboxylic acid-derived molar percentages being 100, e) the top layer (A) exhibits a roughness, Ra, ranging from greater than 60 nm to 400 nm, as determined via DIN 4768, f) the layer thickness of the top layer (A) d A is from 1.7 to 6.0 μm and g) said heatsealable top layer (A) exhibits a seal seam strength with respect to CPET of at least about 1.5 N/15 mm.