Reflective roofing granules having coating including a cristobalite component and processes for making the same
AssigneeCovia Solutions Inc.
InventorJason Lamb
Life of this patent
Estimating the term…
Abstract
A roofing granule includes a core and a coating on the core. The coating comprises at least 10 wt. % of a cristobalite component, titanium dioxide, clay, and a hardener. A weight ratio of the amount of cristobalite component to the amount of titanium dioxide in the coating is from about 1:1 to about 5:1. Accordingly, the roofing granule exhibits an improvement in L* value of at least 6% as compared to an L* value of the core alone and/or an improvement in solar reflectivity of at least 5% as compared to a solar reflectivity of the core alone.
Claims29
A roofing granule comprising:
- a core;
- and
- a coating on the core, the coating comprising:
- at least 10 wt. % of a cristobalite component;
- titanium dioxide;
- clay;
- and
- a hardener,
- wherein the roofing granule exhibits an improvement in L* value of at least 6% as compared to an L* value of the core alone.
A coating composition for a roofing granule, the coating composition comprising
- at least 10 wt. % of a cristobalite component;
- titanium dioxide;
- clay;
- and
- a hardener,
- wherein, when applied to a core comprising nepheline syenite and calcined to form a roofing granule, the resulting roofing granule exhibits an improvement in L* value of at least 6% as compared to an L* value of the core alone.
A roofing granule comprising:
- a core;
- and
- a coating on the core, the coating comprising:
- at least 10 wt. % of a cristobalite component;
- titanium dioxide;
- clay;
- and
- a hardener,
- wherein the roofing granule exhibits an improvement in solar reflectivity of at least 5% as compared to a solar reflectivity of the core alone.
Dependencies are inferred from the claim text.