SEALLING OFF LEAF AND PRODUCTION METHOD

摘要

Process comprises superposition of layers of polyvinyl chloride on a layer of polyethylene terephthalate. The layers are bonded by thermoadhesive varnish, for protection of water piping. Prior to the superposition, the PVC layers are contacted with a heated cylindrical surface, and then they are contacted with an elastic cylindrical surface and a rigid heated cylindrical surface after superposition.