Solar-Reflective Roofing Granules with Hollow Glass Spheres
Assignee3M Innovative Properties Company
InventorKristin M. Amsden
Life of this patent
Estimating the term…
Abstract
The present disclosure relates to roofing granule having a base granule with at least one layer on the base granule that includes hollow glass spheres embedded in a ceramic matrix and a roofing article having a substrate and a plurality of any embodiment of roofing granules described above. The disclosure additionally relates to a roofing granule precursor mixture containing base granules, an aluminum silicate, an alkali metal silicate, and hollow glass spheres. The disclosure also relates to a method of making roofing granules including providing base granules; applying a coating containing hollow glass spheres, an aluminum silicate, an alkali metal silicate to the base granules; and heating the coated granules to a temperature between about 550° F. and about 1000° F.
Claims21
A roofing granule comprising:
- a base granule;
- and
- at least one layer on the base granule comprising hollow glass spheres embedded in a ceramic matrix.
(canceled)
A roofing granule precursor mixture comprising:
- base granules, an aluminum silicate, an alkali metal silicate, and hollow glass spheres.
A method of making roofing granules comprising:
- providing base granules;
- applying a coating containing hollow glass spheres, an aluminum silicate, an alkali metal silicate to the base granules;
- and
- heating the coated granules to a temperature between about 550° F. and about 1000° F.
Dependencies are inferred from the claim text.