Layer of reaction product of epoxy and phosphorus materials and curing agent on substrate

• US 7,476,444 B2
• Filed: 09/15/2006
• Issued: 01/13/2009
• Est. Priority Date: 11/06/2002
• Status: Expired due to Term

• Current Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Original Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Inventors: Nugent, Richard M Jr., Jones, Dennis W., Le Disert, Yves, Deronne, Laurent, Gray, Ralph C., Pawlik, Michael J.
• Primary Examiner(s): SELLERS, ROBERT E
• Application Number:
  US11/521,823
• Publication Number:
  US 20070009742A1
• Time in Patent Office: 851 Days
• Field of Search: None
• US Class Current: 428/418
• CPC Class Codes: C08G 59/1488 containing phosphorus
• CPC Class Codes: C08G 59/4071 phosphorus containing compounds
• CPC Class Codes: C08L 2666/16 Addition or condensation polymers of aldehydes or ketones according to C08L59/00 - C08L61/00; Derivatives thereof
• CPC Class Codes: C08L 2666/40 Phosphorus-containing compounds
• CPC Class Codes: C09D 163/00 Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
• CPC Class Codes: C09D 5/08 Anti-corrosive paints
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/31511 Of epoxy ether
• CPC Class Codes: Y10T 428/31515 As intermediate layer
• CPC Class Codes: Y10T 428/31522 Next to metal
• CPC Class Codes: Y10T 428/31529 Next to metal
• CPC Class Codes: Y10T 428/31678 Of metal

Abstract

A corrosion resistant, alkali resistant coating composition is disclosed. The composition comprises a binder comprising a reaction product of an epoxy-containing material and a phosphorus-containing material together with a curing agent. Aminoplasts, especially melamine-based aminoplasts, are particularly suitable curing agents. A source of silicon can optionally be included. The compositions also provide excellent adhesion and can be used with or without a weldable primer. The compositions are applied to and cured on a metal substrate.

Claims

1. A weldable, corrosion resistant layer deposited on a substrate, wherein the weldable layer has a thickness of from 0.1 micron to 1.0 micron, is substantially free of conductive pigments, and is comprised of the cured reaction product of:

a) the reaction product of at least one epoxy-functional material and at least one phosphorus-containing material, wherein the equivalent ratio of the phosphorous-containing material to epoxy-containing material is within the range of 1.6;

1 and 5;

1; and

b) a curing agent.

2. A coating layer combination comprising the weldable, corrosion resistant layer of claim 1 directly adjacent to a weldable coating layer comprising an electroconductive pigment and a binder.

3. The layer of claim 1, wherein the epoxy-containing material is a polyglycidyl ether of a polyhydric phenol.

4. The layer of claim 3, wherein the polyhydric phenol is Bisphenol A.

5. The layer of claim 1, wherein the number average molecular weight of the epoxy-containing material is 220 to 25,000, as determined by multiplying the epoxy equivalent by the epoxy functionality.

6. The layer of claim 1, wherein the phosphorus-containing material is selected from the group consisting of phosphoric acid, a phosphonic acid, and phosphorous acid.

7. The layer of claim 1, wherein the curing agent is selected from the group consisting of aminoplast resins, polyisocyanates, polyacids, organometallic complexed materials, polyamines, and polyamides.

8. The layer of claim 7, wherein the curing agent is an aminoplast that is a melamine-formaldehyde condensate comprising at least 40 weight percent of imino groups.

9. The layer of claim 1, wherein the weldable, corrosion resistant layer further comprises one or more corrosion resistant pigments.

10. A metal substrate at least partially coated with the weldable, corrosion resistant layer of claim 1.