| 摘要 |
An impact resistant shingle is provided, wherein the base mat is impregnated with an asphaltic material, with an asphaltic material on the upper surface of the shingle, and wherein another asphaltic material is disposed on the rear surface of the shingle, which other asphaltic material is softer with greater elongation than the asphaltic material used elsewhere in the shingle, such that crack resistance is afforded because energy from impact on the shingle is dissipated.
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