Indicator Coatings for Metal Surfaces

• US 20150140338A1
• Filed: 06/10/2013
• Published: 05/21/2015
• Est. Priority Date: 06/08/2012
• Status: Abandoned Application

• Current Assignee: PRC-DeSoto International, Inc. (Nouryon BV)
• Original Assignee: Pcr-Desoto International Incorporated
• Inventors: Morris, Eric L.
• Application Number:
  US14/405,580
• Publication Number:
  US 20150140338A1
• Time in Patent Office: Days
• US Class Current: 428/413
• CPC Class Codes: B05D 1/36 Successively applying liquids or other fluent materials, e.g. without intermediate treatment
• CPC Class Codes: B05D 3/10 by other chemical means
• CPC Class Codes: C09D 5/08 Anti-corrosive paints
• CPC Class Codes: C09D 5/084 Inorganic compounds
• CPC Class Codes: C09D 5/29 for multicolour effects
• CPC Class Codes: C09D 7/41 Organic pigments; Organic dyes
• CPC Class Codes: C09D 7/48 Stabilisers against degradation by oxygen, light or heat
• CPC Class Codes: C09D 7/63 organic
• CPC Class Codes: C23C 22/34 containing fluorides or complex fluorides
• CPC Class Codes: C23C 22/60 using alkaline aqueous solutions with pH greater than 8
• CPC Class Codes: C23C 22/68 using aqueous solutions with pH between 6 and 8
• CPC Class Codes: C23C 22/73 characterised by the process
• CPC Class Codes: C23C 22/83 Chemical after-treatment
• CPC Class Codes: C23C 22/84 Dyeing
• CPC Class Codes: C23C 2222/10 Use of solutions containing trivalent chromium but free of hexavalent chromium
• CPC Class Codes: C23C 28/00 Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
• CPC Class Codes: C23F 11/08 in other liquids
• CPC Class Codes: C23F 11/185 Refractory metal-containing compounds
• CPC Class Codes: G01N 21/80 Indicating pH value
• CPC Class Codes: G01N 31/22 using chemical indicators G01N31/02 takes precedence
• CPC Class Codes: Y10T 428/31511 : Of epoxy ether
• CPC Class Codes: Y10T 428/31551 : Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]

Abstract

Methods and compositions for treating a substrate are provided. The composition contains a corrosion-inhibiting metal cation and a conjugated compound.

Claims

1. A composition comprising:

a) a corrosion-inhibiting metal cation; and

b) a conjugated compound.

2. The composition of claim 1, wherein the corrosion-inhibiting metal cation comprises a rare earth salt.

3. The composition of claim 2, wherein the rare earth salt comprises a praseodymium, cerium and/or yttrium salt.

4. The composition of claim 1, wherein the corrosion-inhibiting metal cation comprises a lithium salt.

5. The composition of claim 1, wherein the composition further comprises an azole compound.

6. The composition of claim 1, wherein the conjugated compound comprises an indicator compound.

7. The composition of claim 5, wherein the indicator compound changes color when exposed to a metal ion.

8. The composition of claim 6, wherein the indicator compound changes color when exposed to an alkaline pH.

9. The composition of claim 6, wherein the indicator compound changes color when exposed to an acidic pH.

10. The composition of claim 6, wherein the conjugated compound comprises catechol violet and/or xylenol orange and/or hematoxylin.

11. The composition of claim 1, wherein the conjugated compound does not comprise a fluorescent indicator.

12. The composition of claim 1, wherein the composition additionally comprises an oxidizing agent and/or polyvinylpyrrolidone.

13. The composition of claim 1, wherein the composition is substantially free of chromate and/or heavy metal phosphate.

14. The composition of claim 1, wherein the composition is completely free of chromate and/or heavy metal phosphate.

15. A method for treating a substrate comprising:

a) applying to at least a portion of the substrate the composition of claim 1.

16. The method of claim 15, wherein the method further comprises treating the substrate prior to the application of the composition of claim 1.

17. The method of claim 15, wherein treating the substrate prior to the application of the composition of claim 1 comprises rendering at least a portion of the surface of the substrate alkaline.

18. The method of claim 15, wherein treating the substrate prior to the application of the composition of claim 1 comprises rendering at least a portion of the surface of the substrate acidic.

19. The method of claim 15, wherein treating the substrate prior to the application of the composition of claim 1 comprises applying a conversion coating to the substrate.

20. The method of claim 14, wherein the substrate comprises metal.

21. The method of claim 14, wherein the substrate is non-metallic.

22. A substrate treated according to the method of claim 15.

23. A substrate comprising:

a) a layer deposited from the composition of claim 1;

b) a coating layer deposited on at least a portion thereof.

24. The substrate of claim 23, wherein the coating layer of component b comprises epoxy.

25. The substrate of claim 24, wherein the coating layer of component b comprises urethane.