A method for the leucocyte depletion of blood or blood components

摘要

A porous web for filtering fluids has a plurality of adjacent layers of fiber material having anisotropic properties. The anisotropic directions of a given vectorial property of at least two adjacent layers differ one from the other by an angle greater than 0°, and preferably of at least 8°. The porous web is particularly useful as a filter element for the filtration of biological fluids, such as blood and blood components.