Patent ID: 7678467

Claim:
An asphalt shingle comprising: an organic felt or fiberglass mat; a first layer of a chemically-modified, air-blown asphalt and a second layer of a chemically-modified, air-blown asphalt, wherein the mat is coated on its top surface by one of the layers of chemically-modified, air-blown asphalt and the mat is coated on its bottom surface by the other layer of chemically-modified, air-blown asphalt; and a surfacing material embedded into the surface, that is opposed to the mat, of at least one of the chemically-modified, air-blown asphalt layers; wherein said chemically-modified, air-blown asphalt is formed by a process for modifying an asphalt that comprises air blowing the asphalt and mixing polyphosphoric acid with the asphalt before the air blowing, during the air blowing, or a combination thereof to form the chemically-modified, air-blown asphalt.