JPH089668B2 - Hydrophilic membranes and their preparation - Google Patents

Hydrophilic membranes and their preparation


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JPH089668B2 JP61243372A JP24337286A JPH089668B2 JP H089668 B2 JPH089668 B2 JP H089668B2 JP 61243372 A JP61243372 A JP 61243372A JP 24337286 A JP24337286 A JP 24337286A JP H089668 B2 JPH089668 B2 JP H089668B2
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JPS6397634A (en
昌明 島垣
和実 田中
良忠 酒井
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    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0081After-treatment of organic or inorganic membranes
    • B01D67/0088Physical treatment with compounds, e.g. swelling, coating or impregnation
    • B01D67/00Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0081After-treatment of organic or inorganic membranes
    • B01D67/009After-treatment of organic or inorganic membranes with wave-energy, particle-radiation or plasma


【発明の詳細な説明】 [産業上の利用分野] 本発明は、新規な親水化膜およびその製造法に関する。 DETAILED DESCRIPTION OF THE INVENTION [FIELD OF THE INVENTION The present invention relates to a novel hydrophilic membranes and their preparation.

[従来の技術] 従来、過処理や透析処理で用いられる水処理用膜は、グリセリンなどの水溶性膜透過能維持剤を用いた状態、膜素材として親水性高分子を用いた状態、水を共存させた状態、などで供給されてきた。 [Prior Art] Conventionally, water treatment membranes used in over-processing or dialysis treatment, a state of using a water-soluble film permeability maintaining agent, such as glycerin, a state with a hydrophilic polymer as a membrane material, water coexistence is not the state, it has been supplied, and the like. しかし、 But,
では使用に先立って膜透過能維持剤を洗浄除去する必要があり、即時使用ができないこと、では一般にポアサイズが小さくなり、分子量数万以上の成分の分離に使える膜ができにくいこと、では被処理液体が血液である場合など、共存している水を予め被処理液体に変質を与えない液体に置換する必要がある用途があり、即時使用できないことなど、それぞれに問題がある。 In must be washed off the membrane permeability maintaining agents prior to use, can not immediately used, in general a pore size becomes smaller, it is difficult can film that can be used for separation of molecular weight of several 10,000 or more ingredients, the object to be processed such as when the liquid is blood, there is coexistence to which applications must be replaced with a liquid which does not give alteration in advance in the target liquid water, etc. can not be immediately used, there are problems respectively.

一方、膜素材として、ポリエチレン、ポリプロピレン、ポリマーボネート、ポリアクリロニトリル、ポリスルホン、ポリエステル、ポリ2弗化ビニリデン、ポリ4 On the other hand, as the film material, polyethylene, polypropylene, polymers Bo sulfonates, polyacrylonitrile, polysulfones, polyesters, poly 2 fluoride, poly 4
弗化エチレン、ポリメチルメタクリレート、セルローストリアセテートなどの疎水性高分子を主たる素材とした膜が過膜や透析膜として提供されているが、これらの疎水性膜ではやの状態にしておかないと直ちには本来の透過能を発揮できず、したがって前記のように即時使用できない問題は疎水性膜の宿命とされてきた。 Ethylene tetrafluoride, polymethylmethacrylate, as soon as it film mainly material a hydrophobic polymer such as cellulose triacetate is provided as a filtration membrane and a dialysis membrane, unless in the Hayate state in these hydrophobic membranes can not exhibit the inherent permeability, thus can not immediately use problems as described above has been the fate of the hydrophobic membrane. また、疎水性膜に対して親水性成分を導入し、固着させることで即時使用を可能にするという例(例えば、特開昭 Further, examples of introducing a hydrophilic component with respect to the hydrophobic membrane allows the immediate use by affixing (e.g., JP
61−120602、特開昭61−125405、特開昭61−125408、特開昭61−125409、特開昭61−133102、特開昭61−133105 61-120602, JP-A-61-125405, JP-A-61-125408, JP-A-61-125409, JP-A-61-133102, JP-A-61-133105
など)もみられるが、これらでは親水性高分子の固着が不充分で、使用中に膜から親水性成分が溶出してくるなどの問題がある。 Etc.) also found, but these in insufficient sticking of the hydrophilic polymer, there are problems such as coming hydrophilic component is eluted from the membrane during use.

[発明が解決しようとする問題点] 本発明者らは、かかる状況に鑑み、溶出性成分を伴わずに疎水性膜を即時使えるようにするには如何にすべきかにつき鋭意検討を重ねたところ本発明に到達した。 [INVENTION Problems to be Solved] The present inventors, in view of such circumstances, when intensive studies on how should how to be able to use immediately the hydrophobic film without leachable components and it reached the present invention.

[問題点を解決するための手段] 即ち、ポリスルホンを主たる素材とした疎水性膜へ、 [Means for solving the problems] That is, the hydrophobic membrane in which the polysulfone as the main material,
該膜の製造行程中で放射線または/および熱により水不溶化するポリビニルピロリドンを導入することにより、 By introducing a polyvinyl pyrrolidone to water insoluble by radiation and / or heat in the film manufacturing process,
溶出性成分を伴わずにポリスルホン膜を即時使えるようにしうることを見出した。 It found that may to a polysulfone membrane available immediately without the leachable component.

本発明のポリスルホンを主体とした疎水性成分としては、ポリスルホンおよびその誘導体、あるいはポリスルホンを主体とするが共重合成分として親水性成分を少量含む重合体などが用いられ、本手段は平衡吸水率(20 The polysulfone hydrophobic component mainly composed of the present invention, polysulfone and derivatives thereof, or polysulfone mainly to the like polymers containing a small amount of a hydrophilic component as a copolymer component is used, this means the equilibrium water absorption ( 20
℃、相対湿度65%の雰囲気下に1週間置いて測定した吸水率で、水重量/ポリマー重量を%で表示した値)が5 ° C., in water absorption was measured by placing 1 week in an atmosphere of a relative humidity of 65%, the value displayed by the water weight / polymer weight percent) 5
%以下、さらに望ましくは2%以下の素材に適用できる。 % Or less, more preferably be applied to more than 2% of the material.

ポリビニルピロリドンの水不溶化手段として、放射線を照射する方法と加熱する方法とがあるが、ポリスルホンは、耐放射線性および耐熱性に共に優れた素材であるので、両手段を併用することも可能である。 As the water insoluble means polyvinylpyrrolidone, although there are a method of heating a method of irradiating radiation, polysulfone, because it is excellent in both materials the radiation resistance and heat resistance, can be used in combination of both means .

放射線または/および熱により水不溶化する成分として、ビニルピロリドンが用いられるが、その誘導体モノマー、さらには、オリゴマ、ポリマー等であってもよく、本発明でいう製造行程中で導入するビニルピロリドンには、これらポリマー等も含まれる。 By radiation and / or heat as a component for water insoluble, but vinylpyrrolidone is used, the derivative monomer, furthermore, oligomers, may be a polymer such as a vinyl pyrrolidone introduced during the manufacturing process in the present invention also it includes those polymers.

水不溶化手段としての放射線としては、ガンマー線、 As the radiation as water insoluble means, gamma,
紫外線、電子線などが用いられるが、特にガンマー線では浸透性が高いので単一膜だけでなく、膜集合体や膜を組込んだモジュール状態でもポリビニルピロリドンの水不溶化処理が行なえるので好適に用いられる。 UV, but it is used like electron beam, in particular not only a single layer due to its high permeability by a gamma ray, suitably so the water insolubilization treatment of polyvinylpyrrolidone in module status incorporating membrane assemblies or film can be performed used. 水不溶化手段としての加熱手段としては、乾熱、湿熱、温浴加熱のいずれも用いることができる。 The heating means as water insoluble means, it is possible to use dry heat, wet heat, none of the bath heating. 加熱温度としては、ポリスルホンの軟化点や融点、ポリビニルピロリドンの熱分解温度などを考慮する必要があるが、50℃ないし200 The heating temperature, the softening point or melting point of the polysulfone, it is necessary to consider the thermal decomposition temperature of the polyvinylpyrrolidone, but to no 50 ° C. 200
℃が好ましい。 ℃ is preferable. また、加熱処理をポリビニルピロリドンを水不溶化する手段としてだけでなく、ポアサイズの調整手段も兼ね合せた手段として用いることも可能である。 In addition to the polyvinylpyrrolidone to a heat treatment as a means of water insoluble, it is also possible to use as a means of combined doubles as adjusting means pore size.

ポリビニルピロリドンを導入する製膜段階としては、 The film introducing a polyvinyl pyrrolidone,
膜素材へのブロック共重合体化、製膜原液への混入、ポリスルホン膜製膜後の後処理など、いずれの段階でも良いが、製膜原液への混入や後処理による導入が大きな孔を確保しやすいという点、ポリビニルピロリドンの使用量を削減できるという点などで有利である。 Block co-polymerisation of the film material, contamination of the membrane-forming solution, such as post-processing after the polysulfone membrane manufactured film may be at any stage, but introduction by mixing and post-processing to the film-forming solution to secure large pores that easily, that it can reduce the amount of polyvinylpyrrolidone it is advantageous in such. また、放射線照射や加熱処理を膜や膜を組込んだモジュールの殺菌手段を兼ねたものとすることも可能である。 It is also possible to make the irradiation or heat treatment to that also serves as a sterilizer of the module incorporating the film or membrane.

本発明でいう膜の形態は特に限定するものではなく、 Form of a membrane in the present invention is not particularly limited,
例えばシート状、中空糸状、マイクロカプセル状の膜などが挙げられる。 For example, a sheet-like, hollow fiber, such as microencapsulated of film.

以下、本発明の有効性を実施例をもって説明する。 Hereinafter, it will be explained with examples the efficacy of the present invention. そこで用いた測定法は次の通りである。 Therefore, measurement methods used were as follows.

(1) 透水性 中空糸膜の場合は、両端に還流液溶の孔を備えたガラス製のケースに該中空糸膜を挿入し、市販のポッティング剤を用いて小型モジュールを作製し、37℃に保って中空糸内側に水圧をかけ膜を通して外側へ透過する一定時間の水の量と有効膜面積および膜間圧力差から算出する方法で透水性能を測定した。 (1) In the case of water-permeable hollow fiber membrane, inserting the hollow fiber membrane in a glass case equipped with a reflux liquid solvent of holes in both ends, to prepare a small module with a commercial potting agent, 37 ° C. the water permeability was measured by the method of calculating the amount and the effective membrane area and the intermembrane pressure difference of water for a certain time to be transmitted to the outside through the membrane applying a pressure to the hollow fiber inward kept.

平膜の場合は、撹拌円筒セルを用いて同様にして測定した。 For flat films was measured in the same manner using a stirred cylindrical cell.

(2) 溶出物 膜0.5gを70℃温水50ccで1時間加熱して試験液を調製する。 (2) eluate film 0.5g was heated 1 hour at 70 ° C. warm water 50cc to prepare a test solution. 試験液の波長220〜350μmにおける吸光度を測定する。 The absorbance at a wavelength 220~350μm of test liquid is measured. なお、透析型人工腎臓装置承認基準では、本条件での規格を0.1以下としている。 In the dialysis type artificial kidney device approval standards are standards in this condition is 0.1 or less.

[実施例] 実施例1 ポリスルホン(ユーデルポリサルホンP−3500)15 EXAMPLES Example 1 Polysulfone (Yu del polysulfone P-3500) 15
部、ポリビニルビロリドン(K−90)8部、ジメチルアセトアミド75部、水2部からなる原液から製膜した中空糸膜を185℃、1.5時間乾熱処理し、ポリビニルビロリドンの水不溶化処理を施した。 Parts, polyvinyl bi Lori pyrrolidone (K-90) 8 parts, 75 parts of dimethylacetamide, hollow fiber membrane was formed from a stock solution consisting of 2 parts water to 185 ° C., 1.5 hours dry heat treatment, the water insolubilization of polyvinyl bi Lori pyrrolidone It was applied. この完全ドライ膜の透水性を測定したところ15000の値を得た。 The complete to obtain a value of 15000 where the permeability was measured in the dry film. この膜の表面には On the surface of the membrane
0.2μm程度の孔があり、常圧で水漏れ性の良いことから、浄水器用として利用できる。 There is 0.2μm about holes, since good water leak resistance at normal pressure, can be used as water purifier.

実施例2 実施例1と同様にして製膜した中空糸膜を170℃、5 170 ° C. The hollow fiber membrane was formed into a film by the same manner as in Example 1, 5
時間乾燥処理し、親水化膜を作った。 The time the drying process, made a hydrophilic membrane. 本中空糸膜を膜面積0.15m 2になるように束ね、モジュール化後、2.5Mrad Bundled so that the present hollow fiber membrane membrane area 0.15 m 2, after modularization, 2.5 Mrad
γ線照射処理後乾燥し、ドライ膜として牛血(ヘマトクリット値40%、総タンパク濃度65g/dl)での血漿分離性能を測定したところ、温度37℃、膜間圧力差47mmHg、血液流量50ml/minで血漿過流量16ml/minの性能を得た。 Dried after γ ray irradiation treatment, bovine blood (hematocrit value 40%, the total protein concentration 65 g / dl) as a dry film where the plasma separation performance in measured, temperature 37 ° C., transmembrane pressure difference 47 mmHg, the blood flow rate 50ml / to give the performance of the plasma over the flow rate 16ml / min by min.
水がついていないため、初期からタンパク透過率(液中濃度/血液中濃度)が95%を越える優れたドライ採血漿膜としての性能を認めた。 Since water is not attached, from the initial protein permeability (liquid concentration / blood concentration) was observed performance as good dry adopted plasma membrane exceeds 95%.

実施例3 実施例1と同様にして製膜した中空糸膜をモジュール化後、水を充填させ、2.5Mradγ線照射による後処理を施した。 After modularized film hollow fiber membranes in the same manner as in Example 3 Example 1, water was filled and subjected to post-treatment with 2.5Mradγ ​​irradiation. この膜を乾燥後、透水性能を測定したところ11 After drying the film, it was measured the water permeability 11
000の性能を得た。 000 performance was obtained.

実施例4 実施例1〜3の中空糸膜の溶出物試験をしたところ、 Was eluted material test of the hollow fiber membrane of Example 4 Examples 1-3,
すべて220nm〜350nmでの吸光度は0.1以下であった。 All absorbance at 220nm~350nm was 0.1 or less.

───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl. 6識別記号 庁内整理番号 FI 技術表示箇所 C08J 7/00 305 7/04 CEZ T // C08L 81:06 (56)参考文献 特開 昭56−38333(JP,A) 特開 昭56−157437(JP,A) 特開 昭53−134876(JP,A) 特開 昭63−51129(JP,A) 特公 昭56−2094(JP,B2) ────────────────────────────────────────────────── ─── front page continued (51) Int.Cl. 6 Docket No. FI technique in identification symbol Agency display portion C08J 7/00 305 7/04 CEZ T // C08L 81:06 (56) reference JP Akira 56 -38333 (JP, A) JP Akira 56-157437 (JP, A) JP Akira 53-134876 (JP, A) JP Akira 63-51129 (JP, A) Tokuoyake Akira 56-2094 (JP, B2 )

Claims (3)

    【特許請求の範囲】 [The claims]
  1. 【請求項1】ポリスルホンを主体とした疎水性成分と、 The method according to claim 1 Polysulfone mainly to the hydrophobic component,
    物理的に不溶化したポリビニルピロリドンとからなる親水化膜。 Physically insolubilized polyvinylpyrrolidone comprising a hydrophilic membrane.
  2. 【請求項2】親水化膜が、中空糸膜であることを特徴とする請求項1記載の親水化膜。 2. A hydrophilic membrane, hydrophilic membrane of claim 1, wherein the hollow fiber membrane.
  3. 【請求項3】ポリスルホンを主体とした疎水性高分子を主たる素材とした膜の製造工程中でビニルピロリドンを導入し該ビニルピロリドンを放射線または/および熱により水不溶化することを特徴とする親水化膜の製造方法。 3. A hydrophilic, characterized in that the hydrophobic polymer a main material and the film production process by introducing a vinylpyrrolidone said vinylpyrrolidone radiation or / and heat in a mainly composed of polysulfone to water insoluble method of manufacturing the film.
JP61243372A 1986-10-14 1986-10-14 Hydrophilic membranes and their preparation Expired - Lifetime JPH089668B2 (en)

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JPH089668B2 true JPH089668B2 (en) 1996-01-31



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