Multi-component coating method for porous substrates

• US 8,697,190 B2
• Filed: 04/09/2012
• Issued: 04/15/2014
• 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: Evanson, Kevin W., Marty, Brian L., Carlson, Stephen M., Ubel, Andrew
• Primary Examiner(s): WIECZOREK, MICHAEL P
• Application Number:
  US13/442,732
• Publication Number:
  US 20120213931A1
• Time in Patent Office: 736 Days
• Field of Search: 427/136, 427/140, 427/294, 427/333, 427/209, 427/314, 427/532
• US Class Current: 427/333
• CPC Class Codes: B28B 11/04 for coating or applying engobing layersglazing, engobing C04B
• CPC Class Codes: C04B 20/0048 Fibrous materials
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C04B 28/14 containing calcium sulfate cements gypsum-paper plates E04C
• CPC Class Codes: C04B 41/009 characterised by the material treated
• CPC Class Codes: C04B 41/488 Other macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds
• 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 41/71 at least one coating being an organic material

Abstract

The disclosure relates to a coating method including the steps of providing a multi-component coating composition including two or more components, applying each component to a porous substrate, mixing each component with at least one other component thereby causing at least two components to undergo a chemical reaction.

Claims

1. A method comprising:

providing a multi-component coating composition including two or more components, wherein the multi-component coating composition comprises a first component comprising an amino-functional chemical compound, and at least a second component comprising an oxirane-functional chemical compound, and wherein each component in the multi-component coating composition is in a separate container prior to application to a surface of a porous substrate selected from one of a fibrous cement substrate and a gypsum wall board;

introducing each of the first and the second component at a rate corresponding to an application rate for each component;

applying each of the first and the second component to the surface of the porous substrate at the application rate, wherein the first component of the multi-component coating composition is applied to the surface of the substrate before the second component of the multi-component coating composition is applied to the surface of the substrate, and wherein a first component penetration time is allowed to elapse before applying the second component;

mixing each of the first and the second component with at least one other component on the surface of the substrate to form the multi-component coating composition thereon, thereby causing at least two components to undergo a chemical reaction and form a coating.

2. The method of claim 1, wherein the porous substrate is a fibrous cement substrate.

3. The method of claim 1, wherein the multi-component coating composition further comprises at least one additive selected from the group consisting of a catalyst, a wetting agent, or a rheology control agent.

4. The method of claim 1, wherein the multi-component coating composition comprises at least one carrier liquid.

5. The method of claim 1, wherein the porous substrate is a fibrous cement substrate comprising a sheet having a plurality of edges adjoining a first major surface, and a second major surface adjoining the edges opposite the first major surface.

6. The method of claim 5, wherein each component is applied to at least the first major surface and at least one of the edges.

7. The method of claim 6, wherein each component is further applied to the second major surface and each of the edges.

8. The method of claim 1, further comprising removing at least a portion of the multi-component coating composition from a surface of the porous substrate.

9. The method of claim 8, wherein removing at least a portion of the multi-component coating composition from a surface of the porous substrate takes place after allowing at least some of the components to penetrate into the porous substrate.

10. The method of claim 8, further comprising applying at least a portion of the multi-component coating composition removed from the surface of the porous substrate to a surface of a second substrate.

11. The method of claim 10, further comprising mixing at least a portion of the multi-component coating composition removed from the surface of the porous substrate with at least a portion of the multi-component coating composition not previously applied to the substrate to form a recycled coating mixture before applying the recycled coating mixture to a surface of a second substrate.

12. The method of claim 11, wherein removing at least a portion of the multi-component coating composition from the surface of the porous substrate comprises directing a gas stream against at least a portion of the coated surface to remove at least a portion of the multi-component coating composition.

13. The method of claim 1, wherein applying each component to the porous substrate comprises coating the component onto a surface of the porous substrate using one or more of brush coating, knife coating, direct roll coating, reverse roll coating, spray coating, extrusion die coating, curtain coating, flood coating and vacuum coating and wherein the porous substrate is a fibrous cement substrate.

14. The method of claim 1, wherein mixing occurs upon applying each component to the porous substrate.

15. The method of claim 1, wherein the multi-component coating composition is applied to the porous substrate to obtain a dry coating weight of from about 1 g/m² to about 40 g/m².

16. The method of claim 1, wherein the porous substrate is a fibrous cement substrate, and wherein the porous substrate exhibits a water droplet penetration time of from about 1 second to about 15 seconds.

17. The method of claim 1, wherein the porous substrate comprises a sheet having a plurality of edge surfaces adjoining a first major surface, and a second major surface adjoining the edge surfaces opposite the first major surface, wherein each component is applied to at least the first major surface and the plurality of edges.

18. The method of claim 17, wherein the reaction is a cross-linking reaction.

19. The method of claim 1, wherein the first component has a penetration time of 0.5 to 5 seconds.

20. The method of claim 1, wherein the second component has a penetration time of 5 to 15 seconds.

21. The method of claim 1, further comprising heating the porous substrate prior to applying each component to the surface thereof.