Roofing granules comprising base particles that are sintered and have an initial reflectance of at least 0.25

Patent metadata

Field	Value
Publication number	US-9422719-B2
Application number	US-201213729118-A
Country	US
Kind code	B2
Filing date	Dec 28, 2012
Priority date	Dec 29, 2011
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

A roofing product can include roofing granules, wherein the roofing granules include base particles and a coating covering the base particles. The base particles are sintered. The coating has a depth of penetration into an outside surface of at least about 0.5% of an average radius of the base particles. In an embodiment, the coating has a depth of penetration into an outside surface of at least about 2.5 microns into the base particles. Further included is a process of forming the roofing granules.

First claim

What is claimed is:

1. A roofing product comprising roofing granules, wherein the roofing granules comprise:
base particles, wherein the base particles are sintered and have a solar reflectance of greater than about 0.25, as measured by ASTM C1549; and
a coating covering the base particles, wherein the coating has a depth of penetration into an outside surface of the base particles of at least about 0.5% of an average radius of the base particles and wherein a solar reflectance of the coated base particles is decreased by about 0.20 or less, compared to the base particle without the coating.

2. The roofing product of claim 1 , wherein the coating has a depth of penetration not greater than about 10.0%.

3. The roofing product of claim 1 , wherein the base particles are sintered to provide a porous surface morphology.

4. The roofing product of claim 1 , wherein the coating has a total average thickness of about 5 microns to about 50 microns.

5. The roofing product of claim 1 , wherein the roofing granules have a solar reflectance of greater than about 0.25.

6. The roofing product of claim 1 , wherein the base particles have a water absorption of about 3.0 wt. % to about 15.0 wt. %.

7. The roofing product of claim 1 , wherein the roofing product is selected from the group consisting of asphaltic roofing products, metal roofing products, synthetic roofing products, and polymeric roofing products.

8. The roofing product of claim 7 , wherein the roofing product is selected from the group consisting of shingle roofing products, tile roofing products, and membrane roofing products.

9. A roofing product comprising roofing granules, wherein the roofing granules comprise:
base particles, wherein the base particles are sintered and have a solar reflectance of greater than about 0.25, as measured by ASTM C1549; and
a coating covering the base particles, wherein the coating has a depth of penetration into an outside surface of the base particles of at least about 2.5 microns into the base particles and wherein a solar reflectance of the coated base particles is decreased by about 0.20 or less, compared to the base particle without the coating.

10. The roofing product of claim 9 , wherein the depth of penetration into the outside surface is not greater than about 50 microns.

11. The roofing product of claim 9 , wherein the coating comprises an outer portion that has not penetrated into the base particles.

Assignees

• Certain Teed Corp

Inventors

• Shiao Ming Liang
• Fuss Tihana
• Millberg Jennifer A

Classifications

• C01P2006/60

  Optical properties, e.g. expressed in CIELAB-values · CPC title

• Y10T428/2991

  Coated · CPC title

• Y02B80/34

  Cross-Sectional Technologies · mapped topic

• C01P2004/60

  Particles characterised by their size · CPC title

• E04D2001/005

  the roofing elements having a granulated surface · CPC title