Abstract: For separating material mixtures, in particular of thermoplastic plastics mixed with solids, the plasticized material to be separated is fed into the interior (23) of a hollow cylindrical filter body (7). The filtered material is conveyed via ducts (39, 41, 43) to the outside of the filter body (7). The remaining residue is fed by scrapers (19) on a rotatably driven scraper shaft (17) to an outlet provided with a holding-back device (47). The filter body (7) is composed of a single tubular material piece with a smooth inner surface and an outer surface ribbed in the circumferential direction. The filter openings (37) are worked into the bottoms of circumferential grooves (33) formed in the outer surface between the circumferential webs (35) by laser beam or electron beam processing methods. The elastically pretensioned scrapers (19) are supported via the webs (35) at the interior of a housing (9).