Patent attributes
A plurality of granules comprising particulate silicate material bonded together with an inorganic binder, the inorganic binder comprising reaction product of at least alkali silicate and hardener, wherein the hardener is at least one of aluminum phosphate, amorphous aluminosilicate, fluorosilicate, Portland cement, or a calcium silicate, wherein the particulate silicate material is present as at least 50 percent by weight of each granule, based on the total weight of the respective granule, wherein each granule has a total porosity in a range from greater than 0 to 50 percent by volume, based on the total volume of the respective granule, and wherein the granules have Tumble Toughness Value of at least 70 before immersion in water and at least 40 after immersion in water at 20° C.±2° C. for two months. The granules are useful, for example, as roofing granules.
