Asahi Kasei Kogyo Kabushiki Kaisha

Morishita Pharm.

Yasuo Hashino

Fusakazu Hayano

Masatsugu Yoshino

Tsugio Konno

Hitoshi Sawabu

Kazuo Toyomoto

Takashi Nohmi

Kenji Ito

Shinichi Ohkubo

Kohichi Matsumoto

Giichi Sayanagi

Sukeo Kawashima

Kaoru Maeda

Kiyoshi Ichikawa

Aromatic polysulfone type resin hollow fiber membrane and a process for

An inline intravenous final filter unit especially of the bacteria-retentive type and adapted to be incorporated in administering sets for administering infusion solutions to patients. The filter unit comprises a casing having an inlet cap at its one end and an outlet cap at the other end thereof, at least one porous hollow fiber arranged within the casing in parallel to the longitudinal direction thereof and having a porosity rating of 0.1 to 5.mu., the hollow fiber being closed at its one end opposed to the inlet cap and open at the other end thereof opposed to the outlet cap, the hollow fiber further being tightly fixed at the outer peripheral portion of its open end to the inner wall of the casing by a securing member, and the ratio of the total effective filtration area of the hollow fiber to the capacity of the casing being at least about 4:1.

Inline intravenous final filter unit

A semipermeable membrane of a polyaryl ether sulfone having repeating units of the formula, ##STR1## wherein Ar.sup.1 and Ar.sup.2 independently represent ##STR2## wherein X, Y and Z independently represents an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a chlorine atom or a bromine atom; and l, m and n independently represent zero or an integer of 1 to 4, and having a contact angle of its surface to water of at most 65.degree..

Semipermeable membranes of polyaryl ether sulfones

Hollow fibers of acrylonitrile polymers having water-permeability greater than 0.2 ml/cm.sup.2.min.atm and useful as an inexpensive superior ultrafilter, comprising

Method for producing hollow fibers of acrylonitrile polymers for

A semipermeable composite membrane which shows only a small reduction of water permeability even when it is subjected to one time hot water treatment or drying treatment is provided according to the method of the present invention. Said semipermeable composite membrane consists of a porous substance and a reinforcing material embedded therein. Said porous substance has a porous region of network structure at least in one part thereof and numbers of voids in said porous region. Said reinforcing material is a fabric in case of flat type membrane or a braid having a central hollow portion in case of hollow fiber type membrane which is embedded in the wall of the membrane. Said method comprises impregnating said reinforcing material with a polymer solution and treating the impregnated reinforcing material with a coagulating liquid.

Semipermeable composite membranes

An ultrafiltration apparatus comprising a module in which a number of hollow fibers having semipermeable walls, disposed in approximately parallel and collected orderly to form a bundle and fixed with a cast-molding material at at least one end portion thereof, are used as semipermeable membrane, a back washing means and a control means for controlling said module and said back washing means, is presented. Said apparatus can be used for a long time without accompanying reduction of filtration capacity.

Ultrafiltration apparatus

Membranes of acrylonitrile polymers having water-permeability greater than 0.2 ml/cm.sup.2.min.atm and useful as an inexpensive superior ultrafilter, comprising (1) a porous layer or layers existing near and on the surfaces of said membranes, the average sizes of pores contained in said porous layer or layers and existing on each of assumptive parallel planes to the surfaces of said membranes, having such a gradient that said average sizes become smaller toward the surfaces of said membranes, and (2) a reticulate porous layer adjacent to said porous layer or layers (1) and containing therein a succession of voids of cylindrical shape or revolving ellipsoid shape having diameters of 5 - 50.mu. and lengths of at least 10.mu., are prepared by dissolving an acrylonitrile polymer in an aqueous solution of nitric acid of 65 - 95% by weight concentration, casting the resulting solution on a support followed by coagulation in a coagulation bath, or extruding the resulting solution from a slit into a coagulation bath, the coagulation bath being water alone or a nitric acid aqueous solution of 30% by weight or less.

Growing community of inventors

Kashiwa, Japan

Yasuo Hashino