VATTENSKYDD AV I VATTEN SVAELLBAR LERA SANDWICHAD MELLAN SKIKT AV FLEXIBEL VAEVNAD.

摘要

There is disclosed a waterproofing material comprising an intermediate layer of a granular abrasive material (16) e.g.a water-swellable colloidal clay, such as bentonite, sandwiched between two layers (12, 14) of flexible sheet or fabric material wherein the two flexible layers of sheet or fabric material are structurally interconnected through the intermediate layer, such as by needle punching, after lubrication of the clay or sheet material with a liquid, such as water, to interconnect fibres of one fabric layer to the other fabric layer at spaced locations over essentially the entire inner surface areas of both sheet or fabric material layers. IMAGE