Method for electrodepositing zinc and zinc alloy coatings from an alkaline coating bath with reduced depletion of organic bath additives

Method for the galvanic deposition of zinc-nickel coatings from an alkaline coating bath comprising zinc-nickel electrolytes and organic bath additives, which uses as the anode an electrode that is insoluble in the bath and contains metallic manganese and/or manganese oxide, wherein the organic bath additives include amine-containing complexing agents, and wherein the electrode

• 1) is produced from metallic manganese or a manganese-containing alloy, the manganese-containing alloy comprising at least 5% by weight of manganese, or
• 2) is produced from an electrically conductive substrate and a metallic manganese and/or manganese oxide-containing coating applied thereto, the manganese and/or manganese oxide-containing coating comprising at least 5% by weight of manganese, based on the total amount of manganese resulting from metallic manganese and manganese oxide, or
• 3) is produced from a composite material comprising metallic manganese and/or manganese oxide and an electrically conductive material, the composite material comprising at least 5% by weight of manganese, based on the total amount resulting from metallic manganese and manganese oxide.

Galvanic apparatus for the deposition of zinc-nickel coatings from an alkaline coating bath comprising zinc-nickel electrolytes and organic bath additives, which comprises as the anode an insoluble electrode that contains metallic manganese and/or manganese oxide, and comprises an alkaline coating bath with zinc-nickel electrolytes and organic bath additives, including amine-containing complexing agents, and wherein the electrode

• 1) is produced from metallic manganese or a manganese-containing alloy, the manganese-containing alloy comprising at least 5% by weight of manganese, and/or
• 2) is produced from an electrically conductive substrate and a metallic manganese and/or manganese oxide-containing coating applied thereto, the manganese and/or manganese oxide-containing coating comprising at least 5% by weight of manganese, based on the total amount of manganese resulting from metallic manganese and manganese oxide, or
• 3) is produced from a composite material comprising metallic manganese and/or manganese oxide and an electrically conductive material, the composite material comprising at least 5% by weight of manganese, based on the total amount resulting from metallic manganese and manganese oxide.