Abstract: The present invention provides a hollow fiber membrane where the membrane strength and pressure resistance to pressurization from the dialysate side is ensured, the retaining rate of water permeability after the repeated pressure load from outside is high, the resistance to the pressure from outside is excellent and the assembling property into module (low leakage rate at the adhered part) is satisfactory at the same time. The present invention also provides a method for manufacturing the same, and a blood purification module.

Abstract: The present invention provides a hollow fiber membrane where the membrane strength and pressure resistance to pressurization from the dialysate side is ensured, the retaining rate of water permeability after the repeated pressure load from outside is high, the resistance to the pressure from outside is excellent and the assembling property into module (low leakage rate at the adhered part) is satisfactory at the same time. The present invention also provides a method for manufacturing the same, and a blood purification module. An annealing spinning method was found where a spinning dope is discharged from a nozzle into a coagulation bath, an appropriate elongation is applied so as to enhance the membrane strength, an elongation is continued during a water-washing step so as not to relax the elongation, and no elongation is applied during drying whereby the strain is relaxed.

Abstract: Purpose: To provide a blood purifier having a high water permeability, for use in treatment of chronic renal failure, which is not variable in performance during the treatment, independently of a patient's body condition. Solution: The present invention provides a hollow fiber membrane excellent in performance stability, which has an average thickness of from 10 to 50 ?m and an average pore radius of from 150 to 300 ?, and which shows a pure water permeability of 150 to 1,500 mL/m2/hr./mmHg at 37° C., characterized in that the ratio of the overall mass transfer coefficient (Ko?2) of a blood plasma solution of ?2-microgloburin to the overall mass transfer coefficient (Komyo) of an aqueous myoglobin solution (i.e., Ko?2/Komyo) is from 0.7 to 1.0.