摘要 |
<p>An asphalt-based roofing material (10) includes a coating (14) having a top portion (14A) containing a mixture of asphalt and igneous and/or metamorphic rock particles, while the mat portion of the coating contains a mixture of asphalt and a filler which contains less than 10% igneous and/or metamorphic rock particles. In other embodiments, the top portion but not the bottom portion (14C) of the coating meets or exceeds a pliability standard, passes a weathering performance test, or has a high solar reflectance. In another embodiment relating to a laminated roofing material, the top portion but not the bottom portion has viscoelastic properties effective to prevent the coating from sticking to an adjacent shingle in a bundle. The invention also relates to a continuous process of applying first (62) and second (76) coatings to a mat for manufacturing a roofing material. In a first coating operation (60), a first asphalt-based coating is continuously applied to a first surface (52) of the mat so that the first coating saturates the mat an d forms a layer on the first surface. In a second coating operation (74), a second asphalt-based coating is continuously applied to a second surface (54 ) of the mat so that the second coating forms a layer on the second surface. T he second coating has different properties from the first coating.</p> |