Method for treating metal surfaces with compositions comprising zirconium and a polymer

• US 3,912,548 A
• Filed: 07/13/1973
• Issued: 10/14/1975
• Est. Priority Date: 07/13/1973
• Status: Expired due to Term

• Current Assignee: Amchem Products Inc. (Henkel AG & Co KGaA)
• Original Assignee: Harry L. Faigen
• Inventors: Faigen, Harry L.
• Primary Examiner(s): Kendall, Ralph S.
• Assistant Examiner(s): Wolfe, Jr., Charles R.
• Application Number:
  US05/379,138
• Time in Patent Office: 823 Days
• Field of Search: 148/6.16,6.14,6.15R,6.15Z 260/29.6M,29.6MM
• US Class Current: 428/472
• CPC Class Codes: C09D 5/08 Anti-corrosive paints
• CPC Class Codes: C23C 22/68 using aqueous solutions with pH between 6 and 8
• CPC Class Codes: C23C 22/83 Chemical after-treatment

Abstract

The corrosion resistance and siccative finish bonding characteristics of a metal surface are improved by contacting the surface with an aqueous composition consisting of a soluble zirconium compound and a polymeric material. The aqueous composition can be applied to a surface having a conversion coating deposited thereon, to improve the qualities of the coating.

Claims

1. A PROCESS FOR TREATING A METALLIC SURFACE TO IMPROVE THE CORROSION RESISTANCE AND THE SICCATIVE FINISH BONDING CHARACTERISTICS OF SAID SURFACE, COMPRISING CONTACTING THE METALLIC SURFACE WITH AN AQUEOUS COMPOSITION CONSISTING ESSENTIALLY OF A SOLUBLE ZIRCONIUM COMPOUND IN AN AMOUNT OF FROM ABOUT 0.1 GRAMS/LITER TO ABOUT 3.5 GRAMS/LITER, MEASURED AS ZRO2 AND A POLYMERIC MATERIAL IN AN AMOUNT FROM ABOUT 0.1 GRAMS/LITER TO ABOUT 5.0 GRAMS/LITER, WHEREIN THE SAID ZIRCONIUM COMPOUND IS SELECTED FROM THE GROUP CONSISTING OF AMMONIUM CARBONATE AND AMMONIUM FLUOZIRCONATE AND THE POLYMERIC MATERIAL IS SELECTED FROM THE GROUP CONSISTING OF POLYACRYLIC ACID, ESTERS, AND SALTS THEREOF.

2. A process according to claim 1 in which the aqueous composition has a pH from about 6.0 to 8.0.

3. A process according to claim 1 wherein the soluble zirconium compound is ammonium zirconium carbonate.

4. A method for treating a metal surface having thereon a conversion coating comprising applying to said conversion coating an aqueous composition consisting essentially of a soluble zirconium compound in an amount of from about 0.1 grams/liter to about 3.5 grams/liter, measured as ZrO2, and a polymeric material in an amount for about 0.1 grams/liter to about 5.0 grams/liter, wherein the said zirconium compound is selected from the group consisting of ammonium zirconium carbonate and ammonium fluozirconate and the polymeric material is selected from the group consisting of polyacrylic acid, esters, and salts thereof.

5. A process according to claim 4 wherein an overlying siccative coating is thereafter applied to the surface.

6. A method for improving the corrosion resistance and paint bonding characteristics of a metal surface having an initial phosphate conversion coating thereon comprising contacting the surface with an aqueous composition consisting essentially of ammonium zirconium carbonate in an amount from about 0.1 grams/liter to about 3.5 grams/liter and a polymeric material selected from the group consisting of polyacrylic acid, esters, and salts thereof in an amount from about 0.1 grams/liter to about 5.0 grams/liter, thereafter applying an organic final finish coating.

7. A coated metallic surface having thereon a conversion coating which has been contacted with an aqueous composition consisting essentially of ammonium zirconium carbonate in an amount from about 0.1 grams/liter to about 3.5 grams/liter, measured as ZrO2, and polyacrylic acid in an amount from about 0.1 grams/liter to about 5.0 grams/liter, said conversion coating underlying an overlying final finish coating.

8. An aqueous composition for treating a metal surface consisting essentially of from about 0.1 grams/liter to about 3.5 grams/liter of a soluble zirconium compound, measured as ZrO2, the soluble zirconium compound being selected from the group consisting of ammonium zirconium carbonatE and ammonium fluozirconate, and from about 0.1 grams/liter to about 5.0 grams/liter of a polymeric material selected from the group consisting of polyacrylic acid, esters, and salts thereof, said composition having a pH from about 6.0 to about 8.0.