POLYESTER AND POLYAMIDE ADHESION IMPROVERS

• US 3,776,782 A
• Filed: 03/15/1971
• Issued: 12/04/1973
• Est. Priority Date: 03/15/1971
• Status: Expired due to Term

• Current Assignee: BETZ Laboratories Incorporated Somerton RD Trevose PA 19047
• Original Assignee: Masamichi Nagatani, Thomas J. Kiefer
• Inventors: Kiefer, Thomas J., Nagatani, Masamichi
• Primary Examiner(s): Kendall, Ralph S.
• Application Number:
  US05/124,562
• Time in Patent Office: 995 Days
• Field of Search: 260/233.5 148/6.15R,6.15Z,6.16 117/84,165,75
• US Class Current: 428/458
• CPC Class Codes: B05D 7/16 using synthetic lacquers or varnishes
• CPC Class Codes: C09D 167/08 Polyesters modified with higher fatty oils or their acids, or with natural resins or resin acids
• CPC Class Codes: C09D 177/00 Coating compositions based on polyamides obtained by reactions forming a carboxylic amide link in the main chain based on polyhydrazides C09D179/06; based on polyamide-imides C09D179/08; Coating compositions based on derivatives of such polymers
• CPC Class Codes: C09D 5/08 Anti-corrosive paints
• CPC Class Codes: Y10T 428/31681 Next to polyester, polyamide or polyimide [e.g., alkyd, glue, or nylon, etc.]

Abstract

Prior to applying an alkyd paint to a metallic surface or to a pre-paint coating covering a metallic surface, there is applied to said surface or said coating a polyester or a polyamide for the purpose of improving the adhesion of said paint. The polyester or polyamide can be applied from an aqueous rinse solution or from a final rinse solution.

Claims

2. The method according to claim 1 wherein starch phosphate is applied to said wet pre-paint conversion coating.

3. The method according to claim 1 wherein said wet pre-paint conversion coating is rinsed with an aqueous solution containing said polyester or said polyamide.

4. The method according to claim 3 wherein said aqueous solution is a final rinse solution.

5. A method for coating a metallic surface comprising:

A applying to a metallic surface a pre-paint coating-forming solution which forms on said surface a prepaint conversion coating;

B applying to said pre-paint conversion coating while wet a water soluble or colloidally dispersible polyester or polyamide adhesion improver, wherein said adhesion improver is applied from a water rinse which is applied to said pre-paint conversion coating to remove therefrom excess or spent pre-paint coating solution or from a final rinse solution after said pre-paint conversion coating has been water rinsed to remove therefrom excess or spent pre-paint coating solution; and

C thereafter applying an alkyd paint to the pre-paint conversion coating having thereon said adhesion improver;

wherein the amount of adhesion improver applied is sufficient to improve the bond between the paint film formed from said alkyd paint and said pre-paint conversion coating.

6. The method according to claim 5 wherein said adhesion improver is starch phosphate and wherein it is applied to said pre-paint conversion coating by rinsing it with an aqueous solution containing said starch phosphate.

7. A method for coating a metallic surface comprising:

A applying a pre-paint conversion coating to said metallic surface;

B applying an aqueous solution containing starch phosphate to said pre-paint conversion coating; and

C applying an alkyd paint to said pre-paint conversion coating having thereon starch phosphate;

wherein the amount of starch phosphate on said pre-paint conversion coating is at least sufficient to improve the bond between said conversion coating and the paint film formed from said alkyd paint.

8. A method according to claim 7 wherein said pre-paint conversion coating is a zinc phosphate coating.

9. A metallic surface coated according to the method of claim 1.

10. A metallic surface coated according to the method of claim 5.

11. A metallic surface coated according to the method of claim 7.