Abstract: The present invention relates to a method for depositing a zinc-nickel alloy on a substrate, particularly to a method for electrolytically depositing a zinc-nickel alloy on a substrate, wherein a zinc-nickel deposition bath is utilized as a catholyte comprising at least one brightening agent, wherein the at least one brightening agent has a source which is substantially free of, preferably does not comprise, halogen anions. The present invention furthermore relates to a respective aqueous zinc-nickel deposition bath, a respective brightening agent, and a respective use of said brightening agent for replenishing in an aqueous zinc-nickel deposition bath.

Abstract: The present invention is related to a membrane anode system for electrolytic zinc-nickel alloy deposition, a method for electrolytic deposition of a zinc-nickel alloy layer on a substrate to be treated using a membrane anode system, and the use of a membrane anode system for acid or alkaline electrolytic deposition of a zinc-nickel alloy layer on a substrate to be treated by such a method.

Abstract: A method for depositing a zinc-nickel alloy on a substrate, including: (a) providing the substrate, (b) providing an aqueous zinc-nickel deposition bath as catholyte in a compartment, wherein the compartment includes an anode and anolyte, the anolyte being separated from catholyte by a membrane, and the catholyte includes nickel ions, complexing agent, zinc ions, (c) depositing zinc-nickel alloy onto the substrate, wherein after step (c) nickel ions have lower concentration than before step (c), (d) rinsing the zinc-nickel coated substrate in water, obtaining a rinsed zinc-nickel coated substrate and rinse water including a portion of the complexing agent and nickel ions, wherein (i) a portion of rinse water and/or a portion of catholyte is treated in a first treatment compartment to separate water from the complexing agent and the nickel ions, (ii) returning the separated complexing agent to the catholyte, and (iii) adding nickel ion to the catholyte.

Abstract: A method for depositing a zinc-nickel alloy on a substrate, including: (a) providing the substrate, (b) providing an aqueous zinc-nickel deposition bath as catholyte in a compartment, wherein the compartment includes an anode and anolyte, the anolyte being separated from catholyte by a membrane, and the catholyte includes nickel ions, complexing agent, zinc ions, (c) depositing zinc-nickel alloy onto the substrate, wherein after step (c) nickel ions have lower concentration than before step (c), (d) rinsing the zinc-nickel coated substrate in water, obtaining a rinsed zinc-nickel coated substrate and rinse water including a portion of the complexing agent and nickel ions, wherein (i) a portion of rinse water and/or a portion of catholyte is treated in a first treatment compartment to separate water from the complexing agent and the nickel ions, (ii) returning the separated complexing agent to the catholyte, and (iii) adding nickel ion to the catholyte.

Abstract: The present invention is related to a membrane anode system for electrolytic zinc-nickel alloy deposition, a method for electrolytic deposition of a zinc-nickel alloy layer on a substrate to be treated using a membrane anode system, and the use of a membrane anode system for acid or alkaline electrolytic deposition of a zinc-nickel alloy layer on a substrate to be treated by such a method.