Coating systems for cement composite articles

• US 8,932,718 B2
• Filed: 07/09/2007
• Issued: 01/13/2015
• Est. Priority Date: 07/07/2006
• Status: Active Grant

• Current Assignee: Axalta Coating Systems Ip Co Llc (Axalta Coating Systems Ltd.)
• Original Assignee: Valspar Sourcing, Inc. (Sherwin-Williams Company)
• Inventors: Garner, Archie W., Killilea, T. Howard, Cavallin, Carl Lewis, Evanson, Kevin W., Hartinger, Dan, Brandenburger, Larry B., Peterson, Todd A.
• Primary Examiner(s): Shosho, Callie
• Assistant Examiner(s): Fung, Coris
• Application Number:
  US11/775,080
• Publication Number:
  US 20080008895A1
• Time in Patent Office: 2,745 Days
• Field of Search: 428/413
• 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 3/06 by exposure to radiation B05D3/02 takes precedence ; plasma treatment B05D3/141
• CPC Class Codes: B32B 27/12 next to a fibrous or filamentary layer
• CPC Class Codes: B32B 27/18 characterised by the use of special additives
• CPC Class Codes: B32B 27/38 comprising epoxy resins
• CPC Class Codes: C04B 14/04 Silica-rich materials; Silicates
• CPC Class Codes: C04B 20/0048 Fibrous materials
• CPC Class Codes: C04B 2103/0065 Polymers characterised by their glass transition temperature (Tg)
• CPC Class Codes: C04B 2103/54 Pigments; Dyes
• CPC Class Codes: C04B 2111/00482 Coating or impregnation materials
• CPC Class Codes: C04B 2111/00517 for masonry
• CPC Class Codes: C04B 2111/00568 Multiple coating with same or similar material
• CPC Class Codes: C04B 2111/27 Water resistance, i.e. waterproof or water-repellent materials
• CPC Class Codes: C04B 2111/29 Frost-thaw resistance
• CPC Class Codes: C04B 24/2641 Polyacrylates; Polymethacrylates
• CPC Class Codes: C04B 26/14 Polyepoxides
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C04B 41/0045 Irradiation; Radiation, e.g. with UV or IR C04B41/0036 takes precedence
• CPC Class Codes: C04B 41/009 characterised by the material treated
• CPC Class Codes: C04B 41/483 Polyacrylates
• CPC Class Codes: C04B 41/4853 : Epoxides
• CPC Class Codes: C04B 41/4884 : Polyurethanes; Polyisocyanates
• CPC Class Codes: C04B 41/5024 : Silicates C04B41/5022 takes precedence; silico-fluorides C04B41/5018
• CPC Class Codes: C04B 41/52 : Multiple coating or impregnating multiple coating or impregnating with the same composition or with compositions only differing in the concentration of the constituents, is classified as single coating or impregnation
• CPC Class Codes: C04B 41/522 : Multiple coatings, for one of the coatings of which at least one alternative is described
• CPC Class Codes: C04B 41/63 : Macromolecular compounds
• CPC Class Codes: C04B 41/71 : at least one coating being an organic material
• CPC Class Codes: C08F 265/04 : on to polymers of esters
• CPC Class Codes: C08F 291/00 : Macromolecular compounds obtained by polymerising monomers on to macromolecular compounds according to more than one of the groups C08F251/00 - C08F289/00
• CPC Class Codes: C08L 2666/02 : Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/22 : Macromolecular compounds not provided for in C08L2666/16 - C08L2666/20
• CPC Class Codes: C08L 63/00 : Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• CPC Class Codes: C09D 133/068 : containing glycidyl groups
• CPC Class Codes: C09D 133/14 : of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen
• CPC Class Codes: C09D 151/003 : grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds C09D151/04, C09D151/06 take precedence
• CPC Class Codes: C09D 163/00 : Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
• CPC Class Codes: Y10T 428/31511 : Of epoxy ether
• CPC Class Codes: Y10T 428/31855 : Of addition polymer from unsaturated monomers

Abstract

A coating system, a method of coating a substrate, and a coated substrate (e.g., a coated cement fiberboard article) include one or more latex polymers, an aliphatic epoxy resin system, optionally a silicate additive, and optionally one or more olefinic compounds and an initiator. The coating system may be applied in one or more layers and may be applied to all the surfaces of the substrate (e.g., the front side, back side and edges of a board). The coated substrate may then be coated with other optional coatings, e.g., decorative or protective topcoats.

Claims

1. An aqueous coating system comprising:

one or more multistage latex polymers containing between 50 and 90 wt. % hard segments having a Tg between 30 and 130°

C. and between 10 and 50 wt. % soft segments having a Tg between 0 and 25°

C.;

an aliphatic epoxy resin system having an oxirane functional component that is distinct from the one or more multistage latex polymers, wherein the oxirane functional component in the aliphatic epoxy resin system has an epoxy equivalent weight less than 1000; and

wherein the aqueous coating system includes one or more coating compositions that may be applied in one or more layers and contains about 2-50 wt. % aliphatic epoxy resin based on total solids, and the aqueous coating system when dried is block-resistant.

2. The aqueous coating system of claim 1, wherein the the one or more multistage latex polymers comprise one or more epoxy functional groups.

3. The aqueous coating system of claim 2, wherein at least one of the latex polymers is made from glycidyl methacrylate, glycidyl acrylate, 4-hydroxybutyl acrylate glycidylether, and combinations thereof.

4. The aqueous coating system of claim 1, wherein the minimum film forming temperature of a blend of the one or more multistage latex polymers with the oxirane functional component of the aliphatic epoxy resin system is less than about 20°

C.

5. The aqueous coating system of claim 1, wherein the the one or more multistage latex polymers comprise acetoacetoxy-functionality.

6. The aqueous coating system of claim 1, wherein the one or more multistage latex polymers comprise one or more amine groups.

7. The aqueous coating system of claim 1, wherein the aqueous coating system further comprises about 2 to 50 wt. % of a silicate salt;

wherein the silicate salt is potassium silicate, ammonium silicate, sodium silicate, lithium silicate, or mixtures thereof.

8. The aqueous coating system of claim 1, wherein the oxirane functional component is the reaction product of an oxirane precursor molecule with an alcohol containing material or a carboxylic acid containing material.

9. The aqueous coating system of claim 8, wherein the oxirane functional component is the reaction product of an oxirane precursor molecule with an alcohol containing material, and at least a portion of the alcohol containing material is ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 2,2-butylethyl propanediol, hexanediol, diethylene glycol, dipropylene glycol, polyethylene glycols, polypropylene glycols, cyclohexane dimethylol, 2,2,3-trimethylpentanediol, trimethylol propane, ethoxylated trimethylol propane, propoxylated trimethylol propane, glycerine, propoxylated glycerine, pentaerythritol, ethoxylated pentaerythritol, propoxylated pentaerythritol, dipentaerythritol, tripentaerythritol, ethoxylated and propoxylated dipentaerythritol, ethoxylated and propoxylated tri-pentaerythritol, ditrimethylolpropane, hydroxypivalyl hydroxypivalate, hydrogenated bisphenol A, ethoxylated and propoxylated hydrogenated bisphenol A, isosorbide, or mixtures thereof.

10. The aqueous coating system of claim 8, wherein the oxirane functional component is the reaction product of an oxirane precursor molecule with a carboxylic acid containing material, and at least a portion of the carboxylic acid containing material is malonic acid, succinic acid, glutaric acid, sebacic acid, fumaric acid, adipic acid, pimelic acid, hexahydrophthalic acid, 1,3- and 1,4 cyclohexanedicarboxylic acid, orthophthalic acid, isophthalic acid, maleic acid, chlorendic acid, glycolic acid, citric acid, trimellitic acid, lactic acid, caprolactone, or mixtures thereof.

11. The aqueous coating system of claim 8, wherein the oxirane functional component has an epoxy equivalent weight of about 90 to 350.

12. A coated article comprising a substrate, at least a portion of which is coated with one or more layers of the aqueous coating system of claim 1, and one or more layers of a second coating system comprising a latex polymer.

13. A coated article comprising a substrate, at least a portion of which is coated with one or more layers of the aqueous coating system of claim 1, and one or more layers of a second coating system comprising a functionalized latex polymer, a multistage latex polymer, or a functionalized, multistage latex polymer.

14. The aqueous coating system of claim 1, wherein the aqueous coating system further comprises one or more olefinic compounds and is radiation curable.

15. A coated article comprising a substrate, at least a portion of which is coated with one or more layers of the aqueous coating system of claim 1, and one or more layers of a second coating system comprising (i) a latex containing primer, (ii) a latex containing topcoat, or (iii) both (i) and (ii).

16. The coated article of claim 15, wherein the second coating system comprises a functionalized latex polymer, a multistage latex polymer or a functionalized, multistage latex polymer.

17. The coated article of claim 16, wherein the second coating system comprises (i) an acetoacetoxy-functional latex containing primer, or (ii) an acetoacetoxy-functional latex containing topcoat, or (iii) both (i) and (ii).

18. The aqueous coating system of claim 1 wherein the multistage latex polymer has a hard segment having a Tg between 30 and 70°

C.

19. The aqueous coating system of claim 1, wherein the aqueous coating system contains about 20-80 wt. % latex polymer based on total solids.

20. The aqueous coating system of claim 1, wherein the aqueous coating system contains about 2-15 wt. % amine crosslinker based on total solids with a reactive hydrogen equivalent weight between 20 and 500.

21. The aqueous coating system of claim 1, further comprising one or more pigments.

22. The aqueous coating system of claim 1, wherein the aliphatic epoxy resin system acts as a coalescent.

23. The aqueous coating system of claim 22, wherein the minimum film forming temperature of the aqueous coating system is less than about 20°

C.

24. The aqueous coating system of claim 1, wherein the aliphatic epoxy resin system lowers the minimum film forming temperature of the aqueous coating system.

25. The aqueous coating system of claim 24, wherein the minimum film forming temperature of the aqueous coating system is less than about 30°

C.

26. A coated article comprising a substrate, at least a portion of which is coated with one or more layers of the aqueous coating system of claim 1.

27. The coated article according to claim 26, wherein the substrate is cement fiberboard.