A coating agent comprises a binding agentcontaining at least one acrylate copolymer (A) with carboxyl groups and/or at least one acrylate copolymer (B) with epoxide groups, the acrylate copolymers (A) and (B) being obtained by solution polymerization using less than 5% by weight based on the total weight of monomers of one or more polysiloxane macromonomers a.sub.1 having a number-average molecular weight of 1000 to 40,000 and on average 0.5 to 2.5 ethylenically unsaturated double bonds per molecule; and one or more epoxy resins.