A process for the production of polymer hollow fiber membranes

The invention concerns a method of producing hollow fibre polymer membranes in which a polymer is guided through an extruder in order to form the hollow fibre membranes. Before entering a melt-forming extrusion tool of the extruder, the polymer is charged under pressure with gas. As a result of a predetermined pressure drop occurring as the polymer leaves the extruder and of the accompanying expansion of the gas in the polymer, a porous hollow fibre membrane is formed.