US 7,402,214 B2 · Conversion coatings including alkaline earth metal fluoride complexes

Abstract

An aqueous composition for pretreating and depositing a coating on metal substrates is provided. The coating composition includes from about 1,500 to about 55,000 ppm based on the aqueous composition of a Group IIA dissolved metal ion, from about 100 to about 200,000 ppm based on the aqueous composition of a dissolved complex metal fluoride ion wherein the metal atom is selected from Group IIIA, Group IVA, Group IVB metals, Group VA, Group VB metals; and water. The composition is free of Group IIA metal fluoride precipitate achieved by including in the composition a complex metal salt different than the salt associated with the complex metal fluoride ion, with the complex metal salt being capable of complexing free fluoride ions to prevent a precipitation reaction. A process for coating a metal substrate with such an aqueous composition is further provided.

Claims12

Dependent claims

A process for coating a metal substrate comprising:

a) contacting a metal surface with a phosphate-based composition, wherein said phosphate-based composition comprises iron phosphate and stannous ion in an amount ranging from about 10 to about 500 parts per million followed by;
b) contacting said metal surface with an aqueous composition comprising a Group IIA dissolved metal ion;
a dissolved complex metal fluoride ion comprising a metal atom selected from Group IIIA, Group IVA, Group IVB, Group VA, and Group VB metals, and water, wherein the composition is substantially free of Group IIA metal fluoride precipitate followed by;
c) contacting said metal surface with a rinse composition comprising an aqueous solution of a rare earth metal prior to application of a paint to said metal surface.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

10/424,302Filed 28 Apr 2003 · continuation in part

Priority

29 Apr 2002

Published

US 2003/0205299 A118 Dec 2003

Granted

22 Jul 2008

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

C23C 22/83
After-treatment: chemical after-treatment
C23C 22/34
Using aqueous acidic solutions with pH less than 6: containing fluorides or complex fluorides
C23C 22/73
Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material…:…
Y10T 428/12535
Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]: with additional, spatially distinct nonmetal…

Family

Application10/134,761Parent of this continuation-in-part · filed 29 Apr 2002

Application60/435,441Us provisional application · filed 20 Dec 2002

US 2003/0230364 A1Pre-grant publication · published 18 Dec 2003

US 6,749,694 B2Parent of this continuation-in-part

US 2003/0205299 A1Published application

US 7,402,214 B2This patent

From the US filing history. Foreign family members aren’t listed.

Conversion coatings including alkaline earth metal fluoride complexes

Life of this patent

Conversion coatings including alkaline earth metal fluoride complexes

Life of this patent

Abstract

Claims12