| 摘要 |
Improved flexible waterproofing membranes of the preformed pressure- sensitive or self-adhesive bituminous type particularly useful in roofing are described. The membranes are in the form of factory- manufactured, flexible, sheet-like laminates employing (a) a lower layer of waterproofing self-adhesive bituminous composition such as rubberized asphalt non-removably adhered to (b) an upper support layer comprises of a laminate of separate, preformed flexible sheet materials having different coefficients of linear thermal expansion. The uppermost sheet material in the support layer (b) has the higher linear thermal expansion coefficient so that the edges of the applied laminate when exposed to, e.g., solar heating and subsequent cooling, turn downward towards the substrate to be waterproofed, resulting in improved sealability. Additionally, further layers of, e.g., protective films and coatings may be applied to the laminates. |
