Coating system for cement composite articles

• US 8,057,893 B2
• Filed: 07/31/2008
• Issued: 11/15/2011
• Est. Priority Date: 01/31/2006
• Status: Active Grant

• Current Assignee: Axalta Coating Systems Ip Co Llc (Axalta Coating Systems Ltd.)
• Original Assignee: Valspar Sourcing, Inc. (Sherwin-Williams Company)
• Inventors: Herfindal, Larry Lloyd, Killilea, T. Howard, Evanson, Kevin W.
• Primary Examiner(s): Ahmed; Sheeba
• Application Number:
  US12/184,150
• Publication Number:
  US 20090029157A1
• Time in Patent Office: 1,202 Days
• Field of Search: None
• US Class Current: 428/330
• CPC Class Codes: C04B 14/06 Quartz; Sand
• CPC Class Codes: C04B 20/0048 Fibrous materials
• CPC Class Codes: C04B 2103/54 Pigments; Dyes
• CPC Class Codes: C04B 2111/00482 Coating or impregnation materials
• CPC Class Codes: C04B 2111/29 Frost-thaw resistance
• CPC Class Codes: C04B 24/2611 Polyalkenes
• CPC Class Codes: C04B 24/2641 Polyacrylates; Polymethacrylates
• CPC Class Codes: C04B 24/281 Polyepoxides
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C04B 28/26 Silicates of the alkali metals
• CPC Class Codes: C04B 41/009 characterised by the material treated
• CPC Class Codes: C04B 41/483 Polyacrylates
• CPC Class Codes: C04B 41/5089 Silica sols, alkyl, ammonium or alkali metal silicate cements
• 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 41/63 Macromolecular compounds
• CPC Class Codes: C04B 41/71 at least one coating being an organic material
• CPC Class Codes: C08F 257/02 on to polymers of styrene or alkyl-substituted styrenes
• CPC Class Codes: C08F 265/04 on to polymers of esters
• CPC Class Codes: C08F 285/00 Macromolecular compounds obtained by polymerising monomers on to preformed graft polymers
• 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: C08K 3/34 : Silicon-containing compounds
• CPC Class Codes: C08L 2666/02 : Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/14 : Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C08L 51/003 : grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds C08L51/04, C08L51/06 take precedence
• 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: C09J 151/003 : grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds C09J151/04, C09J151/06 take precedence
• CPC Class Codes: Y10T 428/25 : Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/258 : Alkali metal or alkaline earth metal or compound thereof
• CPC Class Codes: Y10T 428/26 : Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 428/269 : including synthetic resin or polymer layer or component
• CPC Class Codes: Y10T 428/31511 : Of epoxy ether
• CPC Class Codes: Y10T 428/31855 : Of addition polymer from unsaturated monomers

Abstract

A coated article including a cement fiberboard substrate and a coating system applied to the substrate, wherein the coating system comprises (i) at least one acid-functional alkali-soluble polymer having a backbone substantially free of linear or branched aliphatic alkyl repeating units having more than 3 backbone carbon carbons, (ii) at least one water-soluble silicate salt and (iii) water.

Claims

1. A coated article including a cement fiberboard substrate and a coating system applied to the substrate, wherein the coating system comprises:

(i) at least one acid-functional alkali-soluble polymer having a backbone substantially free of linear or branched aliphatic alkyl repeating units having more than 3 backbone carbon carbons,

(ii) at least one water-soluble silicate salt, and

(iii) water,

wherein the silicate salt is potassium silicate, sodium silicate, lithium silicate, ammonium silicate or mixtures thereof and is present in an amount of from about 2 to about 50% by weight, based on the total weight of the non-volatile components.

2. The coated article of claim 1, wherein the acid-functional alkali-soluble polymer is derived from a reaction mixture containing at least one acid-functional monomer in an amount sufficient to provide at least 5 wt. % acidic monomers in the reaction mixture.

3. The coated article of claim 1, wherein the acid-functional alkali-soluble polymer is derived from a reaction mixture containing at least one acid-functional monomer in an amount sufficient to provide at least 8 wt. % acidic monomers in the reaction mixture.

4. The coated article of claim 1, wherein the acid-functional alkali-soluble polymer contains less than 8 wt. % linear or branched aliphatic alkyl repeating units having more than 3 backbone carbon carbons.

5. The coated article of claim 1, wherein the acid-functional alkali-soluble polymer has a number average molecular weight of no more than 25,000 daltons.

6. The coated article of claim 1, wherein the acid-functional alkali-soluble polymer is present in an amount of from about 15 to about 80% by weight, based on the total weight of the non-volatile components.

7. The coated article of claim 1, wherein the silicate salt is present in an amount of from about 10 to about 35% by weight, based on the total weight of the non-volatile components.

8. The coated article of claim 1, wherein acid-functional alkali-soluble polymer comprises a multistage latex polymer.

9. The coated article of claim 8, wherein the multistage latex polymer is derived from acetoacetyl ethyl methacrylate.

10. The coated article of claim 1, wherein the coating system further comprises an epoxy resin system.

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

12. The coated article of claim 1, wherein the coating system further comprises a coalescent.

13. The coated article of claim 1, wherein the coated article has a first and a second major surface and four edges, and wherein the article has been coated on both major surfaces and on the four edges with the coating system.

14. The coated article of claim 1, wherein the coating system is applied to a dry film thickness of about 0.005 to about 0.1 mm.

15. The coated article of claim 1, wherein the article has further been coated with a second coating system comprising a latex-containing primer, latex-containing topcoat, or both a latex-containing primer and latex-containing topcoat.

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

17. The coated article of claim 1, wherein the article has further been coated with a second coating system comprising an acetoacetoxy-functional latex-containing primer, acetoacetoxy-functional latex-containing topcoat, or (iii) both an acetoacetoxy-functional latex-containing primer and acetoacetoxy-functional latex-containing topcoat.

18. The coated article of claim 1, wherein the article after cure or hardening can withstand at least 75 freeze-thaw cycles.

19. A method for making a coated article, which method comprises:

providing a cement fiberboard substrate;

coating at least a portion of the substrate with a coating system of claim 1; and

curing or otherwise hardening the coating.

20. The coated article of claim 1, wherein the coating system contains less than 2 weight % volatile organic content based on the total coating system weight.

21. The coated article of claim 1, wherein the coating system contains less than 0.5 weight % volatile organic content based on the total coating system weight.