| 摘要 |
<p>An asphalt for roofing comprises a basic material in the form of bulky non-woven fibre mat constituted of tangled, endless filaments of synthetic fibres, possessing appreciable strength, and asphalt, with which this material is uniformly and completely saturated and coated on both sides. The material possesses appreciable strength and also strain capability enabling it to follow the movements of the underlying roof structure. Specifically the non-woven is made by a needle quilting and perforating process. The pref. endless fibres are polypropylene fibres.</p> |
