JPS61293502A - Separation film for purifying blood - Google Patents

Abstract

PURPOSE:To obtain separation film having effective capacity for permeation of water and sufficient compatibility with blood, permitting long time continuous dialysis or filtration of blood by using polysulfone type resin and regulating the contact angle of the surface of the film with water to a value within a specified range. CONSTITUTION:Polysulfone type resin as expressed by formulas I-III is dissolved in a solvent such as N-methyl-2-pyrrolidone, etc., and a filmforming solution is prepd. by adding propionic acid, etc., thereto. The solution is poured on a flat plate to form film, which is then coagulated by dipping in a coagulating bath contg. water, etc., or hollow yarn film is prepd. by ejecting the solution through a nozzle for prepg. hollow fiber while ejecting simultaneously coagulating liquid such as waterthrough a core nozzle of the above-described nozzle in accordance with a method for spinning hollow yarn membrane by the wet process. Obtd. separating film just after preparation is dipped in a non-solvent such as water and heat-treated at ca.90-150 deg.C. By this method, the contact angle between the surface of the film and water is controlled to 65-80 deg.C.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、慢性あるいは急性の腎不全患者の治療を目的
とした、血液浄化、主として血液透析または血液濾過に
用いられる分離膜に関するもので、分離！ＩＸ表面にお
ける水の接触角を特定の範囲内にコントロールすること
によシ、すぐれた透水性と血液適合性を付与せしめ、長
時間の連続的血液透析または血液濾過を可能にする分離
膜を提供するものである。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a separation membrane used for blood purification, mainly hemodialysis or hemofiltration, for the purpose of treating patients with chronic or acute renal failure. Separation! By controlling the contact angle of water on the IX surface within a specific range, we provide a separation membrane that provides excellent water permeability and blood compatibility and enables long-term continuous hemodialysis or hemofiltration. It is something to do.

〔従来技術〕[Prior art]

血液透析や血液濾過に使用される分離膜には、有効な透
水性能を持ちかつ血球成分の付着が少なく、抗血栓性に
優れ、安定して体外循環を行なうための血液適合性が要
求される。血液適合性と密接に関係しているのは、血液
と接触する分離膜表面の構造であシ、こ−の表面が特定
の範囲の親水性を有することが重要なピイントである。Separation membranes used for hemodialysis and hemofiltration are required to have effective water permeability, minimal adhesion of blood cell components, excellent antithrombotic properties, and blood compatibility for stable extracorporeal circulation. . Closely related to blood compatibility is the structure of the separation membrane surface that comes into contact with blood, and it is important that this surface has hydrophilicity within a specific range.

特に血液ポンプを使用しない血圧駆動による血液透析や
血液濾過においては、膜表面の構造が非常に重要な影響
を及ぼす。Particularly in blood pressure-driven hemodialysis and hemofiltration that do not use a blood pump, the structure of the membrane surface has a very important influence.

親水性と疎水性を表わす指標として水の接触角があるが
、従来、膜表面の水の接触角が６５°以下のものは水に
濡れやすく透水性能の向上することが知られていた（特
開昭５４−１６３７８号公報）０しかしながら、血液透
析や血液濾過に用いる場合、透水性能が高くなると血液
適合性が悪くなる傾向があり、有効な透水性能を持ちか
つ血液適合性に優れた膜は存在しなかった。The contact angle of water is an indicator of hydrophilicity and hydrophobicity, and it has been known that membranes with a water contact angle of 65° or less are easily wetted by water and have improved water permeability (especially However, when used for hemodialysis or hemofiltration, higher water permeability tends to result in poorer blood compatibility, and membranes with effective water permeability and excellent blood compatibility are It didn't exist.

〔発明の目的〕[Purpose of the invention]

本発明者らは、有効な透水性能を持ちかつ血液適合性の
優れた分離膜を得んとして研究した結果、ポリスルホン
系樹脂から成り、膜表面での水の接触角が特定の範囲内
にある分離膜が有効な透水性能を持ちかつ血液適合性に
優れていることを見出し、更にこの知見に基づき徨々の
検討を行なった結果、本発明を完成するに至ったもので
ある。The present inventors conducted research to obtain a separation membrane with effective water permeability and excellent blood compatibility, and found that it is made of polysulfone resin, and the contact angle of water on the membrane surface is within a specific range. It was discovered that the separation membrane has effective water permeability and excellent blood compatibility, and based on this knowledge, extensive studies were conducted, and as a result, the present invention was completed.

〔発明の構成〕[Structure of the invention]

即ち本発明は、ポリスルホン系樹脂よ構成υ、膜表面に
おける水の接触角が６５〜８０℃の範囲内にあることを
特徴とする血液透析あるいは血液濾過による血液浄化用
分離膜である０ 更に詳細に本発明の説明を行なうと、プリスルホン系樹
脂よシなる分離膜は、ぼりスルホン系樹脂を該樹脂を溶
解し得る極性有機溶剤中に添加剤と共に溶解せしめて製
膜原液とし、製膜後文に熱処理等の適当な処理を行なう
ことにより膜表面の水の接触角を特定の範囲にコントロ
ールし、透水性能と血液適合性を付与せしめるものであ
る。ここでｉｔ？　ＩＪスルホン系樹脂とは、の構造を
有するものである。That is, the present invention is a separation membrane for blood purification by hemodialysis or hemofiltration, which is composed of a polysulfone resin and has a water contact angle on the membrane surface in the range of 65 to 80°C. To explain the present invention, a separation membrane made of presulfone resin is prepared by dissolving the presulfone resin together with additives in a polar organic solvent capable of dissolving the resin to obtain a membrane forming stock solution. By performing appropriate treatments such as heat treatment, the contact angle of water on the membrane surface can be controlled within a specific range, thereby imparting water permeability and blood compatibility. Is it here? The IJ sulfone resin has the following structure.

製膜原液中のポリスルホン系樹脂の濃度は１０〜２５重
量％、好ましくは１２〜２０重量％である。ポリスルホ
ン系樹脂を溶解する極性有機溶剤はジメチルホルムアミ
ド、Ｎ−メチル−２−ピロリドン等が用いられるが、ぼ
りスルホン系樹脂を溶解するものであればこれらに限定
されない。添加剤としては、金属塩またはポリスルホン
系樹脂の非溶剤が挙げられる。金属塩の例としては、１
価または２価の金属塩、すなわちＬｉＣ１１ＬＩＢｒ　
。The concentration of polysulfone resin in the membrane forming stock solution is 10 to 25% by weight, preferably 12 to 20% by weight. Dimethylformamide, N-methyl-2-pyrrolidone and the like are used as the polar organic solvent for dissolving the polysulfone resin, but the solvent is not limited to these as long as it dissolves the polysulfone resin. Examples of additives include metal salts and non-solvents for polysulfone resins. Examples of metal salts include 1
valent or divalent metal salts, i.e. LiC11LIBr
.

ＮａＣ４ＮａＢｒ５ＫＣｔ、　ＫＢｒ、　ＭｇＣ１，２
、ＭｇＢ　ｒ　２、ＣａＣｌ２、ＣａＢｒ　２等が挙げ
られるがこれらに限定されない。NaC4NaBr5KCt, KBr, MgC1,2
, MgBr2, CaCl2, CaBr2, etc., but are not limited to these.

、ｔＦ　ＩＪスルホン系樹脂の非溶剤としては、ケトン
系、エーテル系、フラン系、有機酸系、有機酸、無水物
系、有機酸エステル系、界面活性剤等が挙げられるがこ
れらに限定されない。更に、金属塩と非溶剤の組合わせ
、また２１以上の非溶剤を組合わせることも可能である
。, tF IJ Non-solvents for IJ sulfone-based resins include, but are not limited to, ketone-based, ether-based, furan-based, organic acid-based, organic acids, anhydride-based, organic acid ester-based, and surfactants. Furthermore, combinations of metal salts and nonsolvents, or combinations of 21 or more nonsolvents are also possible.

製膜原液は上記の各成分を混合し、室温から１００℃程
度に加温しながら攪拌溶解して得られる。The film-forming stock solution is obtained by mixing the above-mentioned components and stirring and dissolving the mixture while heating it from room temperature to about 100°C.

平膜を製造する場合は、上記の製膜原液を平板上に流延
した後、凝固浴中に浸漬し凝固せしめることによりて平
膜を得る。また、中空糸膜を製造する場合は、２重管構
造の中空繊維製造用ノズルを用いて、外側の環状口から
製膜原液を、芯部から凝固液を凝固浴中へ吐出し凝固せ
しめる湿式紡糸法によって中空糸膜を得る。凝固浴及び
凝固液の組成は、操作性の点からは水単独であることが
望ましいが、水に金属塩及び／またはヒリスルホン系樹
脂の溶剤、及び／またはポリスルホン系樹脂の非溶剤を
加えることも可能である。凝固液に添加し得る金属塩は
、Ｌｉｃｔ、　ＬｉＢｒ、　ＮａＣ４１ＮａＢｒ、　Ｋ
Ｃｌ。In the case of producing a flat membrane, the above-mentioned membrane-forming stock solution is cast onto a flat plate, and then immersed in a coagulation bath to coagulate, thereby obtaining a flat membrane. In addition, when manufacturing hollow fiber membranes, a wet method is used in which a double-tube hollow fiber manufacturing nozzle is used to discharge the membrane forming stock solution from the outer annular port and the coagulation liquid from the core into the coagulation bath. A hollow fiber membrane is obtained by a spinning method. The composition of the coagulation bath and coagulation liquid is preferably water alone from the viewpoint of operability, but a metal salt and/or a solvent for hyrisulfone resin and/or a non-solvent for polysulfone resin may be added to the water. It is possible. Metal salts that can be added to the coagulation solution include Lict, LiBr, NaC41NaBr, K
Cl.

１Ｇ３ｒ、　ＭｇＣｌ２、ＭｇＢｒ２、ＣａＣｌ２、Ｃ
ａＢｒ２などが挙げられるが、これらに限定されず、ま
た２種以上の金属塩の組合わせも可能である。また、凝
固浴に添加し得るぼりスルホン系樹脂の溶剤は、ジメチ
ルホルムアミド、Ｎ−メチル−２−ピロリドンなどであ
るがこれらに限定されず、また２種以上の溶剤の組合わ
せも可能である。凝固浴に添加し得るプリスルホン系樹
脂の非溶剤は、アルコール系、ケトン系などがあるがこ
れらに限定されず、また２種以上の非溶剤の組み合わせ
も可能である。1G3r, MgCl2, MgBr2, CaCl2, C
Examples include, but are not limited to, aBr2, and a combination of two or more metal salts is also possible. Further, solvents for the sulfone resin that can be added to the coagulation bath include, but are not limited to, dimethylformamide, N-methyl-2-pyrrolidone, etc., and a combination of two or more solvents is also possible. Non-solvents for the presulfone resin that can be added to the coagulation bath include, but are not limited to, alcohol-based and ketone-based solvents, and a combination of two or more types of non-solvents is also possible.

製膜条件として主に温度管理が重要であり通常室温近辺
で行うが、製膜原液の組成によシ室温において不安定な
場合は加温製膜を行い、製膜温度は室温〜１００℃の範
囲が適当である。更に得られた膜には水に不溶性の添加
剤を含む場合もある丸め、エタノール等に浸漬させ脱溶
剤及び脱添加剤を行って後、水に置換する方法が効果的
である。Temperature control is the main important factor in film forming conditions, and it is usually performed around room temperature. However, if the film forming solution is unstable at room temperature due to the composition, heated film forming is performed, and the film forming temperature is between room temperature and 100°C. The range is appropriate. Furthermore, it is effective to round the obtained film, which may contain water-insoluble additives, and to immerse it in ethanol or the like to remove solvent and additives, and then replace it with water.

分離膜の表面の性質は、上記の製膜原液組成、製膜条件
及び凝固浴、凝固液の組成を適当に組合わせることＫよ
ってかなり広範囲に変化させ得るが、製造直後の分離膜
の表面は疎水性が高くほとんど透水性能を持たない。透
水性を持たせ、表面の水の接触角を特定範囲にコントロ
ールするためにはこの製造直後の分離膜をポリスルホン
系樹脂の非溶剤に浸漬し、９０℃以上１５０℃以下の温
度で熱処理を行なうことが効果的である。、ｔ？　ＩＪ
スルホン系樹脂の非溶剤としては、水やエタノール、グ
リセリン等のアルコール類があるがこれらに限定されな
い。また、これらの非溶剤を単独で用いる以外に組合わ
せて用いることも可能である。非溶剤の沸点が熱処理温
度よシも低い場合は加圧下で行なうことも可能である。The properties of the surface of the separation membrane can be varied over a wide range by appropriately combining the above-mentioned membrane-forming stock solution composition, membrane-forming conditions, coagulation bath, and coagulation liquid composition, but the surface properties of the separation membrane immediately after manufacture are It is highly hydrophobic and has almost no water permeability. In order to provide water permeability and control the contact angle of water on the surface within a specific range, the separation membrane immediately after production is immersed in a polysulfone resin non-solvent and heat-treated at a temperature of 90°C or higher and 150°C or lower. This is effective. ,t? I.J.
Non-solvents for sulfone resins include, but are not limited to, water, alcohols such as ethanol, and glycerin. Moreover, it is also possible to use these non-solvents not only alone but also in combination. When the boiling point of the non-solvent is lower than the heat treatment temperature, it is also possible to carry out the treatment under pressure.

また、熱処理時間は通常３０分〜２時間で充分であるが
、１時間程度が望ましい。Further, the heat treatment time is usually sufficient for 30 minutes to 2 hours, but about 1 hour is desirable.

ここで、水の接触角が６５°未満の場合は親水性が高く
な）、初期の透水性能は高いが、膜の表面における血球
成分及び蛋白質等による目詰りのため、凝血が起こり透
水性能が低下し、安定した血液透析や血液濾過が行なえ
なくなる。また、親水性が高いと膜の強度が低下し、膜
の破損の危険性も高くなる。一方、水の接触角が８０’
を越える場合は、疎水性が高くなるため透水性能が低下
し、有効な血液透析や血液濾過が行なえなくなる。Here, if the contact angle of water is less than 65°, the hydrophilicity is high), and the initial water permeability is high, but due to clogging with blood cell components and proteins on the surface of the membrane, blood coagulation occurs and the water permeability decreases. It becomes impossible to perform stable hemodialysis or hemofiltration. Furthermore, if the hydrophilicity is high, the strength of the membrane decreases and the risk of membrane breakage increases. On the other hand, the contact angle of water is 80'
If it exceeds the above, the hydrophobicity increases and the water permeability decreases, making it impossible to perform effective hemodialysis or hemofiltration.

〔発明の効果〕〔Effect of the invention〕

本発明の血液透析または血液濾過用分離膜は、膜表面の
水の接触角を特定の範囲内にコントロールすることによ
シ、すぐれた透水性と血液適合性を付与し、血液透析や
血液濾過を効率よくかつ安定に行ない得ることを可能に
したものである。The separation membrane for hemodialysis or hemofiltration of the present invention has excellent water permeability and blood compatibility by controlling the contact angle of water on the membrane surface within a specific range, and can be used for hemodialysis or hemofiltration. This makes it possible to perform this efficiently and stably.

従って、慢性または急性腎不全患者の治療において、従
来困難とされた２４時間、４８時間といった長時間にわ
たる連続的血液透析法または血液濾過法のみならず、血
液ポンプを使用しない体外循環法に対しても適用できる
など極めて有用である。この地条臓器不全、薬剤治療抵
抗性心不全、浮型等に対しても連続的血液濾過法が効果
的であシ、長時間安定して使用できる血液濾過器を提供
することが可能となる。さらに将来、慢性の腎不全患者
に対して適用可能な携帯型人工腎臓や家庭透析等にも使
用可能と考えられ、応用範囲はかなシ広いものである。Therefore, in the treatment of patients with chronic or acute renal failure, not only continuous hemodialysis or hemofiltration over a long period of 24 or 48 hours, which has traditionally been considered difficult, but also extracorporeal circulation methods that do not use a blood pump are recommended. It is extremely useful as it can also be applied. The continuous hemofiltration method is also effective against striae organ failure, drug-resistant heart failure, floating type, etc., and it becomes possible to provide a hemofilter that can be used stably for a long period of time. Furthermore, in the future, it is thought that it can be used for portable artificial kidneys and home dialysis that can be applied to patients with chronic renal failure, and the range of applications is wide-ranging.

また、現行の血液ピンプを使用した間歇的治療において
も、よシ血液適合性の優れた血液透析器や血液濾過器を
用いることにより、血液成分を損傷するととが少なくな
シより高度の医療を提供することが可能となる。In addition, even in the current intermittent treatment using blood pumps, by using a hemodialyzer or hemofilter with excellent blood compatibility, we can provide more advanced medical treatment without damaging blood components. It becomes possible to provide

以下本発明の実施例について説明する。Examples of the present invention will be described below.

実施例１ 一テルスルホンを１５重ｉｓ、溶剤としてＮ−メチル−
２−ピロリドンを７８重量％、添加剤としてプロピオン
酸を７重量−の割合で混合し、８０℃３時間加熱攪拌を
行ない均一溶液を得た。この製膜原液をガラス板上に０
．１　ｍの厚さに流延した後、室温下で水からなる凝固
浴中に浸漬して凝固せしめ、さらに水洗を行なって溶剤
等を除去し、分離膜を得た。次いで分離膜を水中に浸漬
し、加圧下１２０℃にて１時間熱処理を行った。Example 1 15 times of monotersulfone, N-methyl-
78% by weight of 2-pyrrolidone and 7% by weight of propionic acid as an additive were mixed and heated and stirred at 80° C. for 3 hours to obtain a homogeneous solution. This membrane forming stock solution is placed on a glass plate.
．． After casting to a thickness of 1 m, it was immersed in a water coagulation bath at room temperature to coagulate, and was further washed with water to remove the solvent and the like to obtain a separation membrane. The separation membrane was then immersed in water and heat treated at 120° C. for 1 hour under pressure.

得られた分離膜の純水での透水率は１１００ｍｆｆｉ／
ｈｒ−ｍＨｇ　−Ｊ、重量平均分子量約７万のデキスト
ランの阻止率は５５チであった。この分離膜の表面の水
の接触角を光反射法にょυ測定したところ７３°であっ
た。The water permeability of the obtained separation membrane in pure water is 1100mffi/
hr-mHg-J, the rejection rate of dextran having a weight average molecular weight of about 70,000 was 55 h. The contact angle of water on the surface of this separation membrane was measured using a light reflection method and was found to be 73°.

比較例１ 実施例１の＃膜原液を用い、同様にして分離膜を得た。Comparative example 1 A separation membrane was obtained in the same manner using #membrane stock solution of Example 1.

熱処理を行なわない場合、純水での透水率はＯであシ、
表面の水の接触角は８７°であった。Without heat treatment, the water permeability of pure water is O,
The contact angle of water on the surface was 87°.

実施例２．３ チルスルホンを１７重量％、溶剤としてジメチルホルム
アミド７０重量％、添加剤として無水安息香酸１３重量
％を混合し、８０℃で３時間攪拌し均一溶液を得た。こ
の製膜原液を中空糸製造用ノズルの外側の環状口から、
また芯部からは水を吐出し、水からなる凝固浴へ導いて
凝固せしめ、３０ｍ／分の速度で巻取りを行なった。こ
こで製膜原液及び凝固液の温度は４０℃であった。得ら
れた中空糸膜は内径２５０μ、膜厚４５μであシ、これ
を水洗して溶剤等の除去後、水中に浸漬し加圧下１１０
℃及び１２８℃で１時間熱処理を行ない、それぞれ実施
例２．３とした。Example 2.3 17% by weight of tilsulfone, 70% by weight of dimethylformamide as a solvent, and 13% by weight of benzoic anhydride as an additive were mixed and stirred at 80° C. for 3 hours to obtain a homogeneous solution. This membrane forming stock solution is passed through the outer annular opening of the hollow fiber manufacturing nozzle.
Further, water was discharged from the core, led to a water coagulation bath for coagulation, and wound up at a speed of 30 m/min. Here, the temperature of the film-forming stock solution and coagulation solution was 40°C. The obtained hollow fiber membrane had an inner diameter of 250 μm and a membrane thickness of 45 μm. After washing with water to remove the solvent, etc., it was immersed in water and heated under pressure for 110 μm.
℃ and 128° C. for 1 hour to give Examples 2 and 3, respectively.

それぞれの中空糸膜の純水での透水率および重量平均分
子量約７万のデキストランの阻止率は、それぞれ実施例
２・・・・・・・・・・・・１０５０　ｍｌ　／　ｈｒ
−ｍＨｇ　−ｍ。The water permeability of each hollow fiber membrane in pure water and the rejection rate of dextran with a weight average molecular weight of approximately 70,000 were as in Example 2...1050 ml/hr.
-mHg -m.

６２％；実施例３−−・−１２９０ｍｌ／　ｈｒ−ｗＨ
ｇ　・ｍ１４９％であった。さらに中空糸膜内表面の水
の接触角を毛管上昇法で測定したところ、それぞれ実施
例２・・・・・・・・・・・・７５°、実施例３・・・
曲面・６９°であった。62%; Example 3--1290ml/hr-wH
g·m was 149%. Furthermore, when the contact angle of water on the inner surface of the hollow fiber membrane was measured by the capillary rise method, the results were as follows: Example 2...75°, Example 3...
The curved surface was 69°.

次いでこれらの中空糸の有効長２０ｃｍ、２０００本を
束ね、両端をウレタン接着剤で固定した後切断し、両端
に開口部を持つ膜面積０．３１　ｍのモジエールを得た
。これらのモジュールを用いて、体重約１０ｋｇのピー
グル大の頚部動静脈に外シャントを設置し、血圧駆動に
よる血液濾過を行なった。Next, 2,000 of these hollow fibers with an effective length of 20 cm were bundled, both ends were fixed with urethane adhesive, and then cut to obtain a mosier with a membrane area of 0.31 m and openings at both ends. Using these modules, an external shunt was installed in the carotid artery and vein of a peagle-sized animal weighing about 10 kg, and blood pressure-driven blood filtration was performed.

その際ヘノ６１Ｊンを３００１Ｕ／ｈｒで持続注入した
。At that time, heno-61J was continuously injected at 3001 U/hr.

その結果、実施例２では４００〜６００ｍｆｆ１／ｈｒ
。As a result, in Example 2, 400 to 600 mff1/hr
.

実施例３では７００〜８００　ｍｌ　／ｈｒの濾過量が
得られ、共に１００時間以上の連続血液濾過が可能であ
った。In Example 3, a filtration rate of 700 to 800 ml/hr was obtained, and continuous blood filtration for 100 hours or more was possible in both cases.

比較例２．３ 実施例２．３と同様にして作成した中空糸膜を水洗し溶
剤等を除去した後、比較例２では熱処理を行なわず、比
較例３では水中に浸漬し加圧下１５５℃で３時間熱処理
を行なった。Comparative Example 2.3 A hollow fiber membrane prepared in the same manner as in Example 2.3 was washed with water to remove the solvent, etc., and then heat treatment was not performed in Comparative Example 2, and in Comparative Example 3, it was immersed in water and heated at 155°C under pressure. Heat treatment was performed for 3 hours.

それぞれの中空糸膜の純水での透水率および重量平均分
子量約７万のデキストランの阻止率は、それぞれ比較例
２・・・・・・・・・・・・ＯｍＩ！／ｈｒ−ＩＩＩＩ
Ｈｇ−ｍ１１００チ；比較例３　＝−２０１０ｍｌ　／
ｈｒ−ｍＨｇ　・ｍ１２５チであった。さらに中空糸膜
内表面の水の接触角を毛管上昇法で測定したところ、そ
れぞれ比較例２・・・・・・・・・・・・８５″、比較
例３・・・・・・・・・・・・６１’であった。The water permeability of each hollow fiber membrane in pure water and the rejection rate of dextran having a weight average molecular weight of approximately 70,000 were as compared to Comparative Example 2...OmI! /hr-III
Hg-m1100chi; Comparative Example 3 =-2010ml/
hr-mHg・m125chi. Furthermore, when the contact angle of water on the inner surface of the hollow fiber membrane was measured by the capillary rise method, the results were as follows: Comparative Example 2...85'', Comparative Example 3... ...It was 61'.

次いで実施例２．３と同様にしてモジュールを作成し動
物実験を行なった。その結果、比較例２ではまったく濾
液が得られず、血液濾過による体液交換は不可能であっ
た。また、比較例３では最初１２００ｍｅ／ｈｒの濾過
量が得られたが、開始３０分後に急激に血流量、濾過量
が減少し、１時間後にはほとんどの中空糸が血栓によシ
閉塞し、血液濾過が行なえなくなった。Next, a module was prepared in the same manner as in Example 2.3, and an animal experiment was conducted. As a result, no filtrate was obtained in Comparative Example 2, and body fluid exchange by hemofiltration was impossible. In addition, in Comparative Example 3, a filtration rate of 1200 me/hr was initially obtained, but 30 minutes after the start, the blood flow rate and filtration rate suddenly decreased, and after 1 hour, most of the hollow fibers were occluded by blood clots. Blood filtration is no longer possible.

Claims (2)

【特許請求の範囲】[Claims] （１）ポリスルホン系樹脂より成り、膜表面における水
の接触角が６５〜８０°の範囲内にあることを特徴とす
る血液浄化用分離膜。(1) A separation membrane for blood purification which is made of polysulfone resin and has a contact angle of water on the membrane surface within a range of 65 to 80 degrees. （２）ポリスルホン系樹脂が ▲数式、化学式、表等があります▼、 ▲数式、化学式、表等があります▼または ▲数式、化学式、表等があります▼ の構造を有する重合体より成る、特許請求 の範囲第（１）項記載の血液浄化用分離膜。(2) Polysulfone resin ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲Contains mathematical formulas, chemical formulas, tables, etc.▼ A patent claim consisting of a polymer having the structure A separation membrane for blood purification according to item (1).