ROOFING GRANULES WITH HIGH SOLAR REFLECTANCE, ROOFING PRODUCTS WITH HIGH SOLAR REFLECTANCE, AND PROCESS FOR PREPARING SAME

• US 20110223385A1
• Filed: 03/08/2011
• Published: 09/15/2011
• Est. Priority Date: 03/15/2010
• Status: Abandoned Application

• Current Assignee: CertainTeed Corp. (Compagnie De Saint-Gobain)
• Original Assignee: CertainTeed Corp. (Compagnie De Saint-Gobain)
• Inventors: Kalkanoglu, Husnu, Shiao, Ming Liang
• Application Number:
  US13/043,036
• Publication Number:
  US 20110223385A1
• Time in Patent Office: Days
• US Class Current: 428/144
• CPC Class Codes: C04B 14/108 Shale, slate colliery shale C04B18/125
• CPC Class Codes: C04B 14/20 Mica; Vermiculite mechanical splitting B28D
• CPC Class Codes: C04B 14/34 Metals , e.g. ferro-silicon
• CPC Class Codes: C04B 20/1033 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C04B 20/1051 Organo-metallic compounds; Organo-silicon compounds, e.g. bentone
• CPC Class Codes: C04B 20/1059 Pigments or precursors thereof
• CPC Class Codes: C04B 20/107 Acids or salts thereof
• CPC Class Codes: C04B 20/1085 Waterglass
• CPC Class Codes: C04B 2111/00586 Roofing materials
• CPC Class Codes: C04B 2235/3232 Titanium oxides or titanates, e.g. rutile or anatase
• CPC Class Codes: C04B 2235/349 Clays, e.g. bentonites, smectites such as montmorillonite, vermiculites or kaolines, e.g. illite, talc or sepiolite
• CPC Class Codes: C04B 2235/5292 Flakes, platelets or plates
• CPC Class Codes: C04B 2235/5296 with a defined aspect ratio, e.g. indicating sphericity
• CPC Class Codes: C04B 2235/5427 millimeter or submillimeter sized, i.e. larger than 0,1 mm
• CPC Class Codes: C04B 2235/5463 Particle size distributions
• CPC Class Codes: C04B 2235/9661 Colour
• CPC Class Codes: C04B 33/14 Colouring matters
• CPC Class Codes: C04B 35/62695 Granulation or pelletising devices for shaping artificial aggregates from ceramic mixtures B28B1/004
• CPC Class Codes: C04B 35/62807 Silica or silicates
• CPC Class Codes: C04B 35/62884 by gas phase techniques
• CPC Class Codes: D06N 5/003 : coated with bitumen
• CPC Class Codes: E04B 1/78 : Heat insulating elements E04B1/7662 takes precedence
• CPC Class Codes: E04D 1/22 : of specified materials not covered by any one of groups E04D1/14 - E04D1/205, or of combinations of materials, where at least one is not covered by any one of groups E04D1/14 - E04D1/205
• CPC Class Codes: E04D 2001/005 : the roofing elements having a granulated surface
• CPC Class Codes: E04D 7/005 : characterised by loose or embedded gravel or granules as an outer protection of the roof covering
• CPC Class Codes: Y02A 30/254 : Roof garden systems; Roof coverings with high solar reflectance
• CPC Class Codes: Y02B 80/00 : Architectural or constructional elements improving the thermal performance of buildings
• CPC Class Codes: Y10T 428/2438 : Coated
• CPC Class Codes: Y10T 428/2991 : Coated
• CPC Class Codes: Y10T 428/2993 : Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]

Abstract

A solar heat-reflective roofing product includes a base sheet, and solar heat-reflective roofing granules on top of the base sheet. The granules have a base particle with a flake-like geometry covered by a uniform coating layer. The coating layer has a thickness of at least one mil and includes a coating binder and at least one solar heat-reflective pigment. The solar heat-reflective pigment provides a solar heat reflectance of greater than 70 percent to the granules and the roofing product. Roofing products including roofing shingles and roofing membranes are described.

Claims

1. Solar heat-reflective roofing granules comprising:

a) a base particle having a flake-like geometry, and an average particle size from #5 US mesh to #50 US mesh,

b) a uniform coating layer on the base particle, the coating layer having a thickness of at least one mil, the coating layer comprising a coating binder and at least one solar heat-reflective pigment, the solar heat-reflective pigment providing a solar heat reflectance of greater than 70 percent to the granules.

2. Solar heat-reflective roofing granules according to claim 1, wherein the roofing granules have an aspect ratio of at least 3.

5. Solar heat-reflective roofing granules according to claim 1, wherein the coating layer has a thickness of at least 2 mils.

6. Solar heat-reflective roofing granules according to claim 1, wherein the base particles are selected from the group consisting of crushed slate, slate granules, shale granules, mica granules, metal flakes, and flake-like synthetic particles.

7. Solar heat-reflective roofing granules according to claim 1, wherein the coating binder is selected from the group consisting of metal silicates, fluoropolymers, metal phosphates, silica coating binders, sol-gel coating binders, polysiloxanes, silicones, polyurethanes, and polyacrylates.

8. Solar heat-reflective roofing granules according to claim 1, wherein the at least one solar heat-reflective pigment is selected from the group consisting of titanium dioxide, calcium carbonate, zinc oxide, lithopone, zinc sulphide, white lead, glass microspheres, glass microbubbles, microvoid pigments, and synthetic polymeric opacifiers.

9. Solar heat-reflective roofing granules according to claim 1, which have (a*²+b*²)^1/2 less than 6.

28. Solar heat-reflective roofing granules according to claim 9, having a value of L* of at least one of greater than about 80, greater than about 85 or greater than about 90.

3-4. -4. (canceled)

10. A solar heat-reflective roofing product comprising:

a) a base sheet, and

b) solar heat-reflective roofing granules on top of the base sheet, the granules comprising;

1) a base particle having a flake-like geometry, and an average particle size from #5 US mesh to #50 US mesh,

2) a uniform coating layer on the base particle, the coating layer having a thickness of at least one mil, the coating layer comprising a coating binder and at least one solar heat-reflective pigment, the solar heat-reflective pigment providing a solar heat reflectance of greater than 70 percent to the granules.

11. A solar heat-reflective roofing product according to claim 10 wherein the granules cover at least 85 percent of the surface area of the base sheet.

14. A solar heat-reflective roofing product according to claim 10, wherein the roofing granules particles have an aspect ratio of at least 3.

21. A solar heat-reflective roofing product according to claim 10 wherein the solar heat-reflective roofing granules have (a*²+b*²)^1/2 less than 6.

22. A solar heat-reflective roofing product according to claim 10, the solar heat-reflective roofing granules comprising primary roofing granules, the shingle further comprising secondary roofing granules interspersed among the primary roofing granules.

23. A solar heat-reflective roofing product according to claim 22, the secondary roofing granules including at least one algaecide.

32. A solar heat-reflective roofing product according to claim 10, wherein the roofing product is a roofing membrane.

34. A solar heat-reflective roofing product according to claim 10, wherein the roofing product is a shingle.

12. (canceled)

13. (canceled)

15-20. -20. (canceled)

24. A process for preparing solar heat reflective roofing granules, the process comprising:

a) providing base particles having a flake-like geometry, and an average particle size from #5 US mesh to #50 US mesh,

b) providing a coating composition including a coating binder and at least one solar heat-reflective pigment; and

c) coating the base particles with the coating composition to provide a uniform coating layer on the base particles, the solar heat-reflective pigment providing a solar heat reflectance of greater than 70 percent to the granules.

39. A process according to claim 24, wherein the coating layer has an average coating thickness, and the coating thickness does not vary by more than about 25 percent of the average coating thickness.

25. A process for preparing solar heat reflective roofing products, the process comprising:

a) providing base particles having a flake-like geometry, and an average particle size from #5 US mesh to #50 US mesh,

b) providing a coating composition including a coating binder and at least one solar heat-reflective pigment;

c) coating the base particles with the coating composition to provide a uniform coating layer on the base particles, the solar heat-reflective pigment providing a solar heat reflectance of greater than 70 percent to the granules, thus providing solar heat-reflective roofing granules;

d) providing a bituminous base sheet having an upper surface; and

e) applying the solar heat-reflective roofing granules to the upper surface of the base sheet, the solar heat heat-reflective roofing granules being applied to at least 85 percent of the upper surface.

26. A process according to claim 25 wherein the solar heat-reflective roofing granules are applied to at least 90 percent of the upper surface.

40. A process according to claim 25, wherein the solar heat-reflective roofing granules comprise a first class of granules, and a second class of granules are provided, the second class of granules having a smaller average dimension than the first class of granules, and granules of the second class of granules are applied to the upper surface of the base sheet.

41. A process according to claim 40, wherein the granules of the second class have a size and a shape selected so that granules of the second class of granules will tend to lie in interstitial spaces between granules of the first class of granules.

27. (canceled)

29-31. -31. (canceled)

33. (canceled)

35-38. -38. (canceled)