Patents Assigned to L Hoist North America, Inc.
  • Mineral composition
    Patent number: 8771826
    Abstract: A roofing shingle that contains a roofing granules. The roofing granules contain at least about 95 weight percent of calcium carbonate with a hardgrove grindability index of less than about 70, and from about 0.1 to about 1.0 weight percent of a pigmented material; the pigmented material contains from about 10 to about 35 weight percent of pigment and from about 90 to about 65 weight percent of a resin; and the roofing granules are coated with an amine antistrip agent.
    Type: Grant
    Filed: January 22, 2010
    Date of Patent: July 8, 2014
    Assignee: L Hoist North America, Inc.
    Inventors: Robert H. Whitaker, Richard Brann, Randall P. Downing