Compositions for application to a metal substrate

Patent metadata

Field	Value
Publication number	US-10876211-B2
Application number	US-201113235317-A
Country	US
Kind code	B2
Filing date	Sep 16, 2011
Priority date	Sep 16, 2011
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

A corrosion resistant pretreatment composition for coating a metal substrate is provided. The composition comprises an aqueous carrier, one or more Group IA metal ions, wherein at least one of the Group 1A metal ions comprises a lithium compound, a hydroxide; and a phosphate or a halide. A process for treating a metal substrate with a lithium based coating is also provided, as well as a process for treating a metal substrate with a non-chrome conversion coating process.

First claim

What is claimed is:

1. A conversion composition for application to an aluminum substrate, the composition comprising:
an aqueous carrier;
at least one Group 1A metal ion;
a hydroxide ion;
a phosphate ion comprising (PO 4 ) 3− ; and
one or more additional components selected from the group consisting of polyvinylpyrrolidone, fluoride, a carbonate, a surfactant, a thickener, allantoin, 1,5-Dimercapto-1,3,4-thiadiazole, a halide, a silane, and an alcohol;
wherein contact of the conversion composition with a surface of the substrate leads to precipitation of a coating thereon; and
wherein the pH of the composition is greater than 10.

2. The conversion composition of claim 1 , wherein the conversion composition is substantially free of metals other than the than Group 1A metals.

3. The conversion composition of claim 1 , wherein the composition is substantially free of Group 3 through Group 12 metals.

4. The conversion composition of claim 1 , wherein at least one of the Group 1A metal ions comprises lithium.

5. The conversion composition of claim 4 , wherein the lithium is provided by a compound present in an amount of 0.02 g/1000 g of conversion composition to 12 g/1000 g of conversion composition.

6. The conversion composition of claim 4 , wherein a second Group 1A metal ion is selected from the group consisting of sodium, potassium, and combinations thereof.

7. The conversion composition of claim 5 , wherein the sodium is provided by a compound present in an amount of 0.2 g/1000 g of conversion composition to 16 g/1000 g of conversion composition.

8. The conversion composition of claim 1 , wherein the hydroxide ion is provided by a compound present in an amount of 0.09 g/1000 g of conversion composition to 16 g/1000 g of conversion composition.

9. The conversion composition of claim 1 , wherein the phosphate ion further comprises a pyrophosphate (P 2 O 7 ) 4− , and/or a polyphosphate.

10. The conversion composition of claim 1 , wherein the phosphate ion further comprises a di-hydrogen phosphate (H 2 PO 4 ) − , and/or a pyrophosphate (P 2 O 7 ) 4− .

11. The conversion composition of claim 1 , wherein the phosphate ion further comprises an organophosphate compound.

12. The conversion composition of claim 1 , wherein the phosphate ion is provided by a compound present in an amount of 0.2 g/1000 g of conversion composition to 16 g/1000 g of conversion composition.

13. The conversion composition of claim 1 , wherein the carbonate ion is provided by a compound present in an amount of 0.05 g/1000 g of conversion composition to 12 g/1000 g of conversion composition.

14. The conversion composition of claim 1 , wherein the composition is substantially chromate free.

15. A substrate, comprising:
a coating formed on at least a portion of a surface of the substrate by the composition of claim 1 .

Assignees

• Morris Eric L
• Prc Desoto Int Inc

Inventors

• Morris Eric L

Classifications

• C23G1/14

  with alkaline solutions · CPC title

• C23C22/78 Primary

  Pretreatment of the material to be coated · CPC title

• C23G1/22

  Light metals · CPC title

• C23C22/66

  Treatment of aluminium or alloys based thereon · CPC title

• C23C22/83

  Chemical after-treatment · CPC title