Adhesion-promoted , heatsealable and peelable polyester film, process for its production and its use

A coextruded, biaxially oriented polyester film which has a base layer (B) and has a heatsealable outer layer (A) that can be peeled from APET/CPET and from CPET, where

• the outer layer (A) comprises
• a) from 60 to 99% by weight of polyester and
• b) from 1 to 10% by weight of inorganic and/or organic particles with a median diameter d50 of from 2 to 8 μm,
• and where
• c) the polyester is composed of from 12 to 89 mol % of units derived from at least one aromatic dicarboxylic acid and of from 11 to 88 mol % of units derived from at least one aliphatic dicarboxylic acid,
• where the total of the dicarboxylic-acid-derived molar percentages is 100, the non-sealable surface of the film has been rendered adhesion-promoting,
• d) the ratio calculated from the particle size d50 of the particles and the layer thickness dA of the outer layer (A) is greater than or equal to 1.1, and
• e) said outer layer (A) exhibits a surface roughness, Ra, ranging from greater than 60 to 400 nm, as determined via DIN 4768.