Organometallic adhesion promoters for paint-over-chrome plated polymers

A method for forming a robust polymeric paint coating on a metal-coated plastic substrate, the method comprising:

• forming a metal coating on a plastic substrate, wherein the metal coating comprises a first metal selected from the group consisting of chromium, nickel, and combinations thereof;
• applying an organometallic adhesion promoter over the metal coating, wherein the organometallic adhesion promoter comprises (i) a transition metal selected from the group consisting of:
• zirconium (Zr), titanium (Ti), chromium (Cr), and combinations thereof, (ii) a first ligand complexed to the transition metal comprising an organofunctional group selected from the group consisting of:
• amino, glycidyloxy, hydroxy, carboxy, allyl, vinyl, acrylate, meth(acrylate), and combinations thereof, and (iii) a second ligand complexed to the transition metal having an alkoxy group;
• and
• applying one or more layers of an organic paint precursor material over the organometallic adhesion promoter, wherein the alkoxy group of the second ligand of the organometallic adhesion promoter is capable of reacting with the metal-coated plastic substrate and the organofunctional group of the first ligand reacts with at least a portion of the organic paint precursor material to form the robust polymeric paint coating over the metal coating on the plastic substrate.

A robust transparent polymeric paint coating on a metal-coated plastic substrate comprising:

• a metal coating on a plastic substrate, wherein the metal coating comprises a first metal selected from chromium (Cr), nickel (Ni), and combinations and alloys thereof;
• an organometallic adhesion promoter layer disposed over the metal coating, wherein the organometallic adhesion promoter layer comprises (i) a transition metal selected from the group consisting of:
• zirconium (Zr), titanium (Ti), chromium (Cr), and combinations thereof, (ii) a first ligand complexed to the transition metal comprising an organofunctional group selected from the group consisting of:
• amino, glycidyloxy, hydroxy, carboxy, allyl, vinyl, acrylate, meth(acrylate), other unsaturated hydrocarbon groups, nitrogen-containing organic groups, halides, epoxides, and combinations thereof, and (iii) a second ligand complexed to the transition metal having a hydrolysable functional group selected from the group consisting of:
• an alkoxy group, an aryloxy group, and a carboxy group;
• and
• one or more layers of a polymeric paint coating disposed over the organometallic adhesion promoter layer, wherein the hydrolysable functional group of the second ligand of the organometallic adhesion promoter layer is capable of reacting with the metal coating on the plastic substrate and the organofunctional group of the first ligand reacts with at least a portion of the polymeric paint coating to form a robust bond between the polymeric paint coating and the metal-coated plastic substrate.