PURPOSE: To obtain a hollow fiber for an atrificial kidney, by extruding a cellulose ester solution into a filamentary form, extruding a solvent, an aqueous solution of a water-soluble salt or monoterpene or a liquid containing it into the inside of the filamentary material, and introducing the filamentary material into a coagulating solution.
CONSTITUTION: A cellulose ester is dissolved in an organic solvent, e.g. dimethylformamide, and the resultant solution is extruded through an annular slit into a filamentary material. Any one type selected from (A) a solvent for the cellulose ester and/or a swelling agent or a liquid containing at least one of them, (B) an aqueous solution containing a water-soluble salt in an amount sufficient to cause the phase separation from the solution and (C) a monoterpene (or a liquid containing it) is extruded into the inside of the filamentary material simultaneously with the extrusion. The filamentary material is then introduced into a coagulating solution of an alkaline liquid to give the aimed fiber.
EFFECT: The hollow fiber having a membrane thickness ≥10μ, an ultrafiltration ratio ≥5ml/hr.m2.mmHg and a permeability coefficient (K) to vitamin B12≥ 40×10-4cm/min can be obtained.
ICHIGE NORIYUKI
SONOBE HISAKO
NAGASE TOSHIO
KANEKO NORIAKI
NIINA AKIHIKO
ICHIKAWA KOUJI
SAITOU TETSUO
