Metal pretreatment composition containing zirconium, copper, and metal chelating agents and related coatings on metal substrates

摘要

Disclosed is a zirconium-based metal pretreatment coating composition that includes a metal chelator that chelates copper in the metal pretreatment coating composition and thereby improves adhesion of paints to a metal substrate coated with the pretreatment coating composition and the chelating agent is present in a sufficient amount to ensure that in the deposited pretreatment coating on the metal substrate the average total atomic % of copper to atomic % of zirconium is equal to or less than 1.1. The pretreatment coating composition is useful for treating a variety of metal substrates.

主权项

1. An article of manufacture comprising a coated metal substrate which has been coated according to a method comprising steps of:
a) contacting a metal substrate with a pre-rinse comprising a copper chelating agent, and optionally copper, prior to application of a zirconium-based pretreatment coating composition to the metal substrate; b) applying to the metal substrate a zirconium-based metal pretreatment coating composition comprising dissolved Zr, a source of fluoride, optionally materials comprising one or more of silicon, boron and yttrium and optional added dissolved Cu, thereby forming a pretreatment coating on the metal substrate; wherein the copper chelating agent is present in the pre-rinse in an amount sufficient to control the amount of copper deposited onto the metal substrate by the zirconium-based pretreatment coating composition such that an average total ratio of atomic % of Cu to atomic % of Zr in the pretreatment coating deposited on the metal substrate is in a range of 0.0001 and 1.1.