PROBLEM TO BE SOLVED: To provide a hollow fiber membrane having an antioxidative property similar to that of a prior art in a blood circulation line, and in addition to this, having an effect for suppressing the aggravation of oxidation stress from a dialysate solution side, and a plasticizer adsorption effect.SOLUTION: In a hollow fiber membrane containing an oil-soluble antioxidant, an amount of the oil-soluble antioxidant per effective membrane area 1 m2 is not smaller than 50 mg/m2, and not larger than 600 mg/m2, and when removing cut faces of the hollow fiber membrane from both ends by 5 μm, trisecting a remaining membrane thickness, setting the trisected membrane thicknesses as an inside region, an intermediate region and an outside region, and setting TOF-SIMS standardized peak intensities of the respective regions as li, lc and lo, li is not smaller than 0.18, lc/li is not smaller than 0.80 and not larger than 1.0, and lo/li is not smaller than 0.70 and not larger than 1.0.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2019,JPO&INPIT【課題】血液循環ラインにおいては従来と同様の抗酸化性を有しつつ、これに加えて、透析液側からの酸化ストレスの亢進を抑制する効果、および、可塑剤吸着効果も併せ持った中空糸膜及び血液浄化器を提供すること。【解決手段】脂溶性抗酸化剤を含む中空糸膜であって、有効膜面積1m2あたりの脂溶性抗酸化剤量が、50mg/m2以上600mg/m2以下であり、前記中空糸膜の切断面を両端から5μmを外して、残りの膜厚を3等分し、それぞれ内側領域、中間領域、外側領域とした場合の各領域におけるTOF-SIMS規格化ピーク強度を、各々、Ii、Ic及びIoとしたときに、Iiが0.18以上であり、Ic/Iiが0.80以上1.0以下であり、かつIo/Iiが0.70以上1.0以下である、中空糸膜。【選択図】図1
