A filter (1a, 1b, 1c, 1d) Blood Processing which includes: a Filter Element (5) in the form of a sheet,A flexible Container (9) on the input side and a flexible Container (11) on the output side to intersperse the filter element (5),A Hole (9a) input is provided in the container (9) flexible input side and receives Blood not processedAnd a Hole (11a) output is provided on the flexible Container (11) on the output side and discharge Blood processed by the filter element (5) comprising the filter (1a, 1b,1c, 1d): a film (7) setting Flow path (5) arranged between the Filter Element and the flexible Container (11) on the output Side,A first portion (13) of Board shaped belt to seal at least the filter element (5) and (7) of the Blade fixing Flow PATH,And has to be separated from the flexible Container (11) on the output Side,And a second portion (15) of o-ring Seals at least flexible Container (9) of the input side and the flexible Container (11) on the output Side,And is provided to surround the filter element (5) and (7) of the Blade fixing Flow PATH, wherein the first portion (13): Board includes a pair of side portions(13C) arranged opposite each other with the output Hole (11a) interposed between them, and a portion (13a, 13b) communication connected to the pair of side Portions (13C) portion (13a,13b) communication includes a portion (13a) of Lower side and an upper side portion (13b),The fixing plate (7) is a sheet Flow path which includes RIBS which consist of only a couple of Ribs (7a) which are arranged between the pair of side Portions (13C) andOpposite each other with the output Hole (11a) interposed between them,A slot (7b) disposed between the pair of Ribs (7a) to communicate with a Concave portion (6) formed by the portion (13a, 13b) communication,(7c) dissemination and Openings are arranged outside the pair of Ribs (7th),And Open continuously since the ribs (7a) at the lateral portion (13C) and communicate with the Concave portion (6) formed by the later
