The invention relates to a co-extruded, biaxially oriented polyester film consisting of a base layer and at least one outer layer. The film contains a UV-stabilizer and has a matt outer layer which contains a mixture and/or a blend of two components (I) and (II), whereby component (I) is substantially a polyethylene terephthalate homopolymer or a polyethylene terephthalate copolymer, or a mixture of polyethylene terephthalate homopolymers or polyethyleneterephthalate copolymers, and component (II) is a polymer which contains at least one sulphonate group.