Dialyzer cartridge of roll type particularly for extracorporal artificial kidneys

A dialyser cartridge of roll type particularly for extracorporal artificial kidneys comprising an outer casing, a support element consisting of a length of plastics material sheet spirally wound in said casing and having a longitudinally extending web and at least one type of projections on both sides of the web distributed in aligned arrangement to provide spaces between the projections defining fluid flow passages for the dialysing liquid, the aligned arrangement of said projections on one side of said web defining a first plurality of parallel directional lines and the aligned arrangement of the projections on the other side of said web defining a second plurality of parallel centerlines, a flattened tubular dialyser membrane longitudinally and transversely coextensive with said support element and disposed, along turns thereof between said one side of said support element and said other side of the subsequent turn of said support element and wherein, the improvement consists in that at least part of said first plurality of directional lines is arranged at an angle with respect to said second plurality of directional lines, said first and said second plurality of directional lines crossing each other at least partially and at least part of said projections on one side of said web abutting with the interposition of said membrane against the projections on the other side of the web thereby to prevent embedding of said projections on one side of said web in the spaces between said projections on the other side of said web.