| 摘要 |
A weather-resistant covering is made of three superimposed sheets of vulcanizable material such as ethylene-propylene copolymers, e.g. ethylene-propylene-diene terpolymer. The inner layer contains a vulcanization accelerator and advantageously the outer layers do not. An additional inner layer such as a non-woven textile fabric can be provided to increase strength and dimensional stability. A roof can be covered by placing a plurality of strips of such covering side-by-side with slight overlap, welding them together into impervious seams by application of a volatile solvent or swelling agent for the outer layers. |
