Abstract: The present invention concerns a method for increasing the adhesion between a chromium surface and a lacquer wherein said chromium surface is contacted with an aqueous solution comprising at least one phosphorous compound according to formulae R1—P(O)(OR2)(OR3) 1 and R1—O—P(O)(OR2)(OR3) 2 wherein R1 is a C1 to C12 alkyl group, linear, branched or cyclic comprising at least one polar residue and R2 and R3 are independently selected from the group consisting of hydrogen, lithium, sodium, potassium, ammonium and C1 to C4 alkyl while passing an external electrical current through said substrate and at least one anode wherein said substrate serves as the cathode.

Abstract: The present invention concerns a method for increasing the adhesion between a chromium surface and a lacquer wherein said chromium surface is contacted with an aqueous solution comprising at least one phosphorous compound according to formulae R1—P(O)(OR2R3) 1 and R1—O—P(O)(OR2R3) 2 wherein R1 is a C1 to C12 alkyl group, linear, branched or cyclic comprising at least one polar residue and R2 and R3 are independently selected from the group consisting of hydrogen, lithium, sodium, potassium, ammonium and C1 to C4 alkyl while passing an external electrical current through said substrate and at least one anode wherein said substrate serves as the cathode.