Coating system for sag resistant formaldehyde-free fibrous panels

• US 20070055012A1
• Filed: 08/23/2005
• Published: 03/08/2007
• Est. Priority Date: 08/23/2005
• Status: Active Grant

• Current Assignee: AWI Licensing Company
• Original Assignee: AWI Licensing Company
• Inventors: Caldwell, Kenneth
• Granted Patent: US 7,851,052 B2
• Time in Patent Office: Days
• US Class Current: 525/54.100
• CPC Class Codes: B32B 2307/102 Insulating
• CPC Class Codes: B32B 2307/734 Dimensional stability
• CPC Class Codes: B32B 2607/00 Walls, panels
• CPC Class Codes: B32B 33/00 Layered products characterised by particular properties or particular surface features, e.g. particular surface coatings; Layered products designed for particular purposes not covered by another single class
• CPC Class Codes: B32B 37/0015 to avoid warp or curl
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08K 7/00 Use of ingredients characterised by shape
• CPC Class Codes: C09D 7/61 inorganic
• CPC Class Codes: C09D 7/69 Particle size larger than 1000 nm
• CPC Class Codes: E04C 2/16 of fibres, chips, vegetable stems, or the like
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree

Abstract

A coating system on a fibrous substrate, such as a fibrous ceiling panel, having a first surface and a second surface. A first coating is disposed on the first surface of the substrate and includes a first binder and a first filler material. A second coating may be disposed on the second surface of the substrate. The second coating includes a second binder and a second filler material. The first coating and the second coating expand at different rates in the presence of humidity in order to help prevent sagging of the substrate in presence of humidity. The first coating is preferably a hydrophobic coating having a large particle size, high elastic modulus filler material. The second coating is preferably a hydrophilic coating having a lower concentration of high elastic modulus material and a polymer having a hydrophilic moiety.

Claims

1. A coated sag resistant building material comprising:

a substrate having a first surface and a second surface;

a substantially hydrophobic first coating disposed on the first surface, the first coating comprising a first binder and a first filler material;

a substantially hydrophilic second coating disposed on the second surface, the second coating comprising a second binder and a second filler material; and

wherein the first coating and the second coating expand at different rates in the presence of humidity.

2. The building material of claim 1, wherein the substrate is a fibrous panel.

3. The building material of claim 1, wherein the first coating and second coating are substantially formaldehyde free.

4. The building material of claim 1, wherein the hydrophobic coating experiences substantially no expansion in the presence of humidity.

5. The building material of claim 1, wherein the first filler material has a platelet geometry.

6. The building material of claim 1, wherein the first filler material is a material having a particle size of from about 10 microns to about 250 microns.

7. The building material of claim 1, wherein the first filler material is selected from the group consisting of mica, aluminum silicate, ground stainless steel, titanium carbide, magnesium-partially stabilized zirconia, quartz, borosilicate glass and combinations thereof.

8. The building material of claim 1, wherein the first binder material is a polymer selected from the group consisting of starch, protein, natural polymers, thermal set acrylics, vinyl polymers, thermoplastic acrylics, epoxies urethanes, polyesters, polyamides and combinations thereof.

9. The building material of claim 1, wherein the coated substrate sags at a rate less than about 134 mils/ft.

10. The building material of claim 1, wherein the coated substrate sags at a rate less than about 89 mils/ft.

11. A coated sag resistant building material comprising:

a substrate having a first surface and a second surface;

a substantially hydrophobic coating disposed on one or both of the first surface and the second surface, the coating comprising a binder and a filler material; and

wherein the hydrophobic coating provides the substrate with a resistance to sagging.

12. The building material of claim 11, wherein the substrate is a fibrous panel.

13. The building material of claim 11, wherein the hydrophobic coating is substantially formaldehyde free.

14. The building material of claim 11, wherein the hydrophobic coating experiences substantially no expansion in the presence of humidity.

15. The building material of claim 11, wherein the filler material has a platelet geometry.

16. The building material of claim 11, wherein the filler material is a material having a particle size of from about 10 microns to about 250 microns.

17. The building material of claim 11, wherein the filler material is selected from the group consisting of mica, aluminum silicate, ground stainless steel, titanium carbide, magnesium-partially stabilized zirconia, quartz, borosilicate glass, and combinations thereof.

18. The building material of claim 11, wherein the binder material is a polymer selected from the group consisting of starch, protein, natural polymers, thermal set acrylics, vinyl polymers, thermoplastic acrylics, epoxies urethanes, polyesters, polyamides and combinations thereof.

19. The building material of claim 11, wherein the coated substrate sags at a rate less than about 134 mils/ft.

20. The building material of claim 19, wherein the coated substrate sags at a rate less than about 89 mils/ft.

29. The method of claim 18, wherein the coated fibrous panel sags at a rate less than about 89 mils/ft.

21. A method for making a sag-resistant panel comprising:

providing a fibrous panel;

coating a first surface of the fibrous panel with a first coating composition comprising a first polymeric binder and a first filler to produce a substantially hydrophobic first coating, the filler comprising a material having a high modulus of elasticity;

coating a second surface of the fibrous panel with a second coating composition comprising a second polymeric binder comprising a hydrophilic group and a second filler to produce a substantially hydrophilic second coating, the filler comprising a material having a high modulus of elasticity; and

wherein the coated fibrous panel comprises sag resistance in the presence of humidity.

22. The method of claim 21, wherein the first coating and second coating are substantially formaldehyde free.

23. The method of claim 21, wherein the hydrophobic first coating experiences substantially no expansion in the presence of humidity.

24. The method of claim 21, wherein the first filler material has a platelet geometry.

25. The method of claim 21, wherein the first filler material is a material having a particle size of from about 10 microns to about 250 microns.

26. The method of claim 21, wherein the first filler material is selected from the group consisting of mica, aluminum silicate, ground stainless steel, titanium carbide, magnesium-partially stabilized zirconia, quartz, borosilicate glass, and combinations thereof.

27. The method of claim 21, wherein the first binder material is a polymer selected from the group consisting of starch, protein, natural polymers, thermal set acrylics, vinyl polymers, thermoplastic acrylics, epoxies urethanes, polyesters, polyamides and combinations thereof.

28. The method of claim 21, wherein the coated fibrous panel sags at a rate less than about 134 mils/ft.