Coated substrates and methods of preparing the same

Patent metadata

Field	Value
Publication number	US-12018174-B2
Application number	US-201917271303-A
Country	US
Kind code	B2
Filing date	Aug 27, 2019
Priority date	Aug 27, 2018
Publication date	Jun 25, 2024
Grant date	Jun 25, 2024

Abstract

The present invention relates to a substrate having (a) a first material applied to at least a portion of the substrate, and (b) a coating layer deposited from a powder coating composition including a film-forming resin, and optionally a crosslinker that is reactive with the film-forming resin, in direct contact with at least a portion of the substrate to which the first material has been applied. The first material is (i) a catalyst that catalyzes cure of the powder coating composition, (ii) a component reactive with the film-forming resin and/or the crosslinker of the powder coating composition, and/or (iii) a rheology modifier.

First claim

The invention claimed is:

1. A method for improving edge coverage of a powder coating composition on a substrate comprising:
a. contacting at least a portion of a substrate with a first material that is: (i) a catalyst selected from at least one of a phosphonium compound, a quaternary ammonium halide compound, an amine compound, an imidazole compound, a sulfonium compound, and a compound comprising a transition metal and/or post-transition metal, that catalyzes cure of the powder coating composition, (ii) a component reactive with a film-forming resin and/or a crosslinker of the powder coating composition, the component selected from at least one of: an oxazoline-functional crosslinker; a polycarbodiimide functional crosslinker; an epoxy-functional crosslinker; a reactive diluent; and a monomer; and/or (iii) a rheology modifier comprising at least one of, colloidal silica, alumina, chemically modified alumina, and a rubber latex;
b. directly contacting at least a portion of first material on the substrate with the powder coating composition, wherein the powder coating composition comprises a film forming resin and a crosslinker that is reactive with the film forming resin, wherein the film forming resin comprises carboxylic acid or epoxide functional groups and the crosslinker comprises a phenolic resin, an epoxy resin, triglycidyl isocyanurate, a beta-hydroxy (alkyl) amide, a polyacid, an anhydride, an organometallic acid-functional material, a carbodiimide, and/or an oxazoline; and
c. liquidizing the powder coating composition to form a coating layer of the powder coating composition on the substrate, wherein a ratio of dry film thickness of the coating layer formed from the powder coating composition at an edge of the substrate and at 10 mm away from the edge into the center is from 1:3 to 1:15.

2. The method of claim 1 , wherein an interfacial flow of the powder coating composition when liquidized and in contact with at least a portion of the first material on the substrate is lower than an interfacial flow of the same powder composition liquidized under the same conditions that is in contact with an identical substrate with the exception that no first material has been applied.

3. The method of claim 1 , wherein a viscosity of the powder coating composition when liquidized and upon and/or after contact with the first material is higher than a viscosity of the same powder coating composition liquidized under the same conditions that is in contact with an identical substrate with the exception that no first material has been applied.

4. The method of claim 1 , wherein step (a) comprises dipping the substrate in a bath that comprises the first material.

5. The method of claim 4 , wherein the bath comprises a pretreatment bath.

6. The method of claim 5 , wherein the pretreatment bath is a cleaner bath, a deoxidizer bath, a cleaner-coater bath, a rinse conditioner bath, a pretreatment coating bath, a rinsing bath, a sealing bath, or a deionized water rinsing bath.

7. The method of claim 1 , wherein the first material is contained on and/or in a wipe and step (a) comprises wiping the substrate with the wipe.

8. The method of claim 1 , wherein the first material is contained in a liquid formulation and the liquid formulation is sprayed onto the substrate in step (a).

9. The method of claim 8 , wherein the liquid formulation further comprises a surfactant.

10. The method of claim 1 , wherein the first material is deposited onto the substrate by electrodeposition or vapor deposition in step (a).

11. The method of claim 1 , wherein the first material is brushed or rolled onto the substrate in step (a).

12. The method of claim 1 , wherein the first material is a solid and is blasted onto the substrate in step (a) or is sprayed onto the substrate in step (a) as a powder.

13. The method of claim 1 , wherein the substrate is cleaned and coated with the first material in a single step.

14. The method of claim 1 , wherein the substrate is plated with a metal prior to step (a).

15. The method of claim 1 , wherein the substrate comprises an anodized, cast, or forged metal.

16. The method of claim 1 , wherein the substrate is treated prior to step (a).

17. The method of claim 16 , wherein, prior to step (a), the substrate is alkaline cleaned, deoxidized, mechanically cleaned, ultrasonically cleaned, plasma cleaned or etched, exposed to chemical vapor deposition, treated with an adhesion promoter, or any combination thereof.

18. The method of claim 1 , wherein the substrate is pretreated prior to step (a) with a pretreatment composition.

19. The method of claim 18 , wherein the pretreatment composition comprises a sol-gel, iron phosphate, manganese phosphate, zinc phosphate, a rare earth metal, permanganate, zirconium, titanium, a silane, trivalent chrome, chromate, a silicate, molybdenum, a lanthanide, a metal chelate, a metal oxide, hydrotalcite, phosphonic acid, layered double hydroxide, or any combination thereof.

20. The method of claim 18 , wherein, after pretreatment, the substrate is rinsed with, sprayed with, or wiped with a solution that comprises the first material in step (a).

21. The method of claim 18 , wherein the pretreatment composition is dried after application.

22. The method of claim 1 , further comprising step (d), contacting at least a portion of the substrate with a second coating composition.

23. The method of claim 1 , wherein the first material is dried by air and/or heat after step (a).

24. The method of claim 1 , wherein there is no intervening step between step (a) and step (b).

25. The method of claim 1 , wherein first material is applied directly to the substrate.

26. The method of claim 1 , wherein the powder coating composition, upon cure, has an R-value of 75% or greater as compared to an R-value of a coating formed from the powder coating composition applied over a substrate that is free of the first material, where R-value is measured by the R-value test.

27. The method of claim 1 , wherein the dry film thickness of the coating formed from the powder coating composition at the edge of the substrate is 2 μm or greater.

28. The method of claim 1 , wherein the coated substrate has 10% or less linear edge corrosion after 40 cycles as measured by the linear edge corrosion test.

29. A method for improving edge coverage of a powder coating composition on a coil metal substrate comprising:
contacting at least a portion of the metal substrate with a first material that is: (i) a catalyst selected from at least one of a phosphonium compound, a quaternary ammonium halide compound, an amine compound, an imidazole compound, a sulfonium compound, and a compound comprising a transition metal and/or post-transition metal, that catalyzes cure of the powder coating composition, (ii) a component reactive with a film-forming resin and/or a crosslinker of the powder coating composition, the component selected from at least one of: an oxazoline-functional crosslinker; a polycarbodiimide functional crosslinker; an epoxy-functional crosslinker; a reactive diluent; and a monomer; and/or (iii) a rheology modifier comprising at least one of, colloidal silica, alumina, chemically modified alumina, and a rubber latex;
rolling the metal substrate into a coil;
unrolling the coil;
directly contacting at least a portion of the first material on the metal s

Assignees

• Ppg Ind Ohio Inc

Inventors

• Larimer Troy James
• Schneider John R
• Chasser Anthony M
• Woodworth Brian Edward
• Martin Justin Jonathan
• Lemon Steven Joseph
• Niederst Craig Daniel

Classifications

• B05D1/06 Primary

  Applying particulate materials · CPC title

• B05D3/005

  Pretreatment for allowing a non-conductive substrate to be electrostatically coated · CPC title

• B05D3/10

  by other chemical means · CPC title

• B05D3/002

  Pretreatement · CPC title

• C09D175/06

  from polyesters · CPC title