Aqueous coating composition for electroplating lacquer coating of electrically conductive substrates containing bismuth, both present in dissolved form, as well as in undissolved form

摘要

The present invention relates to an aqueous coating composition (A) having a pH in a range from 4.0 to 6.5 and comprising at least one cathodically depositable binder (A1), a total amount of at least 130 ppm of Bi, based on the total weight of (A), including at least 30 ppm of Bi in a form (A3) in solution in (A) and at least 100 ppm of Bi in a form not in solution in (A), and at least one at least bidentate complexing agent (A5) suitable for complexing Bi, (A5) being present in (A) in a fraction of at least 5 mol %, based on the total amount of the Bi present in (A), for at least partly coating an electrically conductive substrate with an electrocoat material, to a method for producing (A), to the use of (A) for at least partly coating an electrically conductive substrate with an electrocoat material, to a corresponding coating method, to an at least partly coated substrate obtainable by this method, and to a method for setting and/or maintaining the concentration of component (A3) and/or (A4) in the coating composition (A) during the coating method.