Colored roofing granules with increased solar heat reflectance, solar heat-reflective shingles, and process for producing same
View Patent ↗Solar-reflective roofing granules having deep-tone colors are formed by coating base mineral particles with a coating composition including an infrared-reflective pigment. Color is provided by colored infrared pigment, light-interference platelet pigment, or a metal oxide.
1. Colored infrared-reflective roofing granules comprising inert base particles with size passing #8 mesh and retaining on #70 mesh coated with a cured coating composition comprising a coating binder and at least one colored, infrared-reflective pigment.
2. Colored infrared-reflective roofing granules according to claim 1 , the colored infrared-reflective roofing granules having an L* value of less than 55.
3. Colored infrared-reflective roofing granules according to claim 1 the colored infrared-reflective roofing granules having an infrared reflectance of at least 25%.
4. Colored infrared-reflective roofing granules according to claim 1 wherein the coating composition further comprises at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, mirrorized silica pigments based upon metal-doped silica, and alumina.
5. Colored infrared-reflective roofing granules according to claim 1 wherein the coating composition further comprises at least one coloring material selected from the group consisting of granule coloring pigments and uv-stabilized dyes.
6. Colored infrared-reflective roofing granules comprising base particles with size passing #8 mesh and retaining on #70 mesh coated with a cured coating composition comprising a coating binder and at least one colored, infrared-reflective pigment wherein the base particles comprise mineral particles coated with a cured base coating composition including a base particle binder, and at least one reflective white pigment.
7. Colored infrared-reflective roofing granules according to claim 6 wherein the at least one reflective white pigment is selected from the group consisting of titanium dioxide, zinc oxide and zinc sulfide.
8. Colored infrared-reflective roofing granules comprising base particles comprising inert mineral particles coated with a cured first coating composition including a base particle binder and at least one reflective white pigment, the base particles being coated with a cured second coating composition including a coating binder, and at least one colorant selected from the group consisting of uv-stabilized dyes and granule coloring pigments.
9. Colored infrared-reflective roofing granules according to claim 8 , the colored infrared-reflective roofing granules having an L* value of less than 55.
10. Colored infrared-reflective roofing granules according to claim 8 the colored infrared-reflective roofing granules having an infrared reflectance of at least 25%.
11. Colored infrared-reflective roofing granules according to claim 8 wherein the second coating composition further comprises at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, mirrorized silica pigments based upon metal-doped silica, and alumina.
12. Colored infrared-reflective roofing granules according to claim 8 wherein the at least one reflective white pigment is selected from the group consisting of titanium dioxide, zinc oxide and zinc sulfide.
13. Colored infrared-reflective roofing granules comprising inert mineral particles coated with a cured first coating composition including a base particle binder and at least one colorant selected from the group consisting of uv-stabilized dyes and granule coloring pigments to form base particles, the base particles being coated with a cured second coating composition including a coating binder and at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, mirrorized silica pigments based upon metal-doped silica, and alumina.
14. Colored infrared-reflective roofing granules according to claim 13 , the colored infrared-reflective roofing granules having an L* value of less than 55.
15. Colored infrared-reflective roofing granules according to claim 13 the colored infrared-reflective roofing granules having an infrared reflectance of at least 25%.
16. Colored infrared-reflective roofing granules according to claim 13 wherein the first coating composition further comprises at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, mirrorized silica pigments based upon metal-doped silica, and alumina.
17. A bituminous roofing product comprising a substrate sheet of a fibrous material saturated with a bituminous coating material and colored, infrared-reflective roofing granules comprising base particles with size passing #8 mesh and retaining on #70 mesh coated with a cured coating composition comprising a coating binder and at least one colored, infrared-reflective pigment.
18. A bituminous roofing product according to claim 17 having an L* value of less than 55.
19. A bituminous roofing product according to claim 17 having an infrared reflectance of at least 25%.
20. A bituminous roofing product according to claim 17 wherein the coating composition further comprises at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, mirrorized silica pigments based upon metal-doped silica, and alumina.
21. A bituminous roofing product according to claim 17 wherein the base particles comprise mineral particles coated with a cured base coating composition including a base coating binder and at least one reflective white pigment.
22. A bituminous roofing product according to claim 21 wherein the at least one reflective white pigment is selected from the group consisting of titanium dioxide, zinc oxide and zinc sulfide.
23. A bituminous roofing product comprising a substrate sheet of a fibrous material saturated with a bituminous coating material and colored infrared-reflective roofing granules comprising base particles comprising inert mineral particles with size passing #8 mesh and retaining on #70 mesh coated with a cured first coating composition including a base particle binder and at least one reflective white pigment, the base particles being coated with a cured second coating composition including a coating binder, and at least colorant selected from the group consisting of uv-stabilized dyes and granule coloring pigments.
24. A bituminous roofing product according to claim 23 having an L* value of less than 55.
25. A bituminous roofing product according to claim 23 having an infrared reflectance of at least 25%.
26. A bituminous roofing product according to claim 23 wherein the second coating composition further comprises at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, mirrorized silica pigments based upon metal-doped silica, and alumina.
27. A bituminous roofing product according to claim 23 wherein the at least one reflective white pigment is selected from the group consisting of titanium dioxide, zinc oxide and zinc sulfide.
28. A bituminous roofing product comprising a substrate sheet of a fibrous material saturated with a bituminous coating material and colored infrared-reflective roofing granules comprising inert mineral particles with size passing #8 mesh and retaining on #70 mesh coated with a cured first coating composition including a base particle binder and at least one colorant selected from the group consisting of uv-stabilized dyes and granule coloring pigments to form base particles, the base particles being coated with a cured second coating composition including a coating binder and at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, and mirrorized silica pigments based upon metal-doped silica.
29. A bituminous roofing product according to claim 28 having an L* value of less than 55.
30. A bituminous roofing product according to claim 28 having an infrared reflectance of at least 25%.
31. A bituminous roofing product according to claim 28 wherein the first coating composition further comprises at least one infrared-reflective functional pigment selected from the group consisting of light-interference platelet pigments including mica, light-interference platelet pigments including titanium dioxide, mirrorized silica pigments based upon metal-doped silica, and alumina.
32. A mineral surfaced asphalt shingle having L*<60 and solar reflectance >25%.
33. A process for preparing a bituminous roofing product, the process comprising:
(a) saturating a sheet of fibrous material with a bituminous coating material to form a substrate, and
(b) applying infrared-reflective roofing granules to the substrate, the infrared-reflective roofing granules comprising base particles coated with a cured coating composition comprising a binder and at least one colored, infrared-reflective pigment.