JPS6214905A - Process of manufacturing microporous - Google Patents
Process of manufacturing microporousInfo
- Publication number
- JPS6214905A JPS6214905A JP60155722A JP15572285A JPS6214905A JP S6214905 A JPS6214905 A JP S6214905A JP 60155722 A JP60155722 A JP 60155722A JP 15572285 A JP15572285 A JP 15572285A JP S6214905 A JPS6214905 A JP S6214905A
- Authority
- JP
- Japan
- Prior art keywords
- membrane
- alcohol
- treatment
- microporous
- microporous membrane
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 13
- 238000000034 method Methods 0.000 title abstract description 6
- 239000012528 membrane Substances 0.000 claims abstract description 27
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000012982 microporous membrane Substances 0.000 claims abstract description 16
- 229920000642 polymer Polymers 0.000 claims abstract description 15
- 229920002492 poly(sulfone) Polymers 0.000 claims abstract description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 24
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 10
- 239000011550 stock solution Substances 0.000 claims description 7
- 238000005345 coagulation Methods 0.000 claims description 6
- 230000015271 coagulation Effects 0.000 claims description 6
- DKGAVHZHDRPRBM-UHFFFAOYSA-N Tert-Butanol Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 claims description 3
- 239000003495 polar organic solvent Substances 0.000 claims description 2
- 125000003118 aryl group Chemical group 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 12
- -1 polypropylene Polymers 0.000 abstract description 8
- 239000003960 organic solvent Substances 0.000 abstract description 5
- 239000004743 Polypropylene Substances 0.000 abstract description 4
- 239000007788 liquid Substances 0.000 abstract description 4
- 229920001155 polypropylene Polymers 0.000 abstract description 4
- 238000005406 washing Methods 0.000 abstract description 4
- 229920002678 cellulose Polymers 0.000 abstract description 3
- 230000001112 coagulating effect Effects 0.000 abstract description 3
- 239000004642 Polyimide Substances 0.000 abstract description 2
- 229920001721 polyimide Polymers 0.000 abstract description 2
- 229920005989 resin Polymers 0.000 abstract description 2
- 239000011347 resin Substances 0.000 abstract description 2
- 239000004952 Polyamide Substances 0.000 abstract 1
- 244000052616 bacterial pathogen Species 0.000 abstract 1
- 229920002647 polyamide Polymers 0.000 abstract 1
- 238000001914 filtration Methods 0.000 description 23
- 239000011148 porous material Substances 0.000 description 11
- 239000002904 solvent Substances 0.000 description 10
- 239000000243 solution Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 238000000926 separation method Methods 0.000 description 6
- 239000003792 electrolyte Substances 0.000 description 5
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 description 3
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 210000004907 gland Anatomy 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 239000004953 Aliphatic polyamide Substances 0.000 description 2
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 2
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 2
- 239000002033 PVDF binder Substances 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 150000001298 alcohols Chemical class 0.000 description 2
- 229920003231 aliphatic polyamide Polymers 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- PHTQWCKDNZKARW-UHFFFAOYSA-N isoamylol Chemical compound CC(C)CCO PHTQWCKDNZKARW-UHFFFAOYSA-N 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Chemical class 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000004745 nonwoven fabric Substances 0.000 description 2
- 239000005518 polymer electrolyte Substances 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- VWDWKYIASSYTQR-UHFFFAOYSA-N sodium nitrate Chemical compound [Na+].[O-][N+]([O-])=O VWDWKYIASSYTQR-UHFFFAOYSA-N 0.000 description 2
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 2
- CTTJWXVQRJUJQW-UHFFFAOYSA-N 2,2-dioctyl-3-sulfobutanedioic acid Chemical compound CCCCCCCCC(C(O)=O)(C(C(O)=O)S(O)(=O)=O)CCCCCCCC CTTJWXVQRJUJQW-UHFFFAOYSA-N 0.000 description 1
- 241000894006 Bacteria Species 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- AMQJEAYHLZJPGS-UHFFFAOYSA-N N-Pentanol Chemical compound CCCCCO AMQJEAYHLZJPGS-UHFFFAOYSA-N 0.000 description 1
- 239000004695 Polyether sulfone Substances 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- VMHLLURERBWHNL-UHFFFAOYSA-M Sodium acetate Chemical compound [Na+].CC([O-])=O VMHLLURERBWHNL-UHFFFAOYSA-M 0.000 description 1
- 239000004280 Sodium formate Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- FDSGHYHRLSWSLQ-UHFFFAOYSA-N dichloromethane;propan-2-one Chemical compound ClCCl.CC(C)=O FDSGHYHRLSWSLQ-UHFFFAOYSA-N 0.000 description 1
- 229960000878 docusate sodium Drugs 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 235000011187 glycerol Nutrition 0.000 description 1
- GNOIPBMMFNIUFM-UHFFFAOYSA-N hexamethylphosphoric triamide Chemical compound CN(C)P(=O)(N(C)C)N(C)C GNOIPBMMFNIUFM-UHFFFAOYSA-N 0.000 description 1
- 239000012456 homogeneous solution Substances 0.000 description 1
- 239000002563 ionic surfactant Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 239000005486 organic electrolyte Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 229920001467 poly(styrenesulfonates) Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920006393 polyether sulfone Polymers 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 229920000036 polyvinylpyrrolidone Polymers 0.000 description 1
- 239000001267 polyvinylpyrrolidone Substances 0.000 description 1
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 description 1
- 239000004323 potassium nitrate Substances 0.000 description 1
- 235000010333 potassium nitrate Nutrition 0.000 description 1
- HNJBEVLQSNELDL-UHFFFAOYSA-N pyrrolidin-2-one Chemical compound O=C1CCCN1 HNJBEVLQSNELDL-UHFFFAOYSA-N 0.000 description 1
- 239000001632 sodium acetate Substances 0.000 description 1
- 235000017281 sodium acetate Nutrition 0.000 description 1
- HLBBKKJFGFRGMU-UHFFFAOYSA-M sodium formate Chemical compound [Na+].[O-]C=O HLBBKKJFGFRGMU-UHFFFAOYSA-M 0.000 description 1
- 235000019254 sodium formate Nutrition 0.000 description 1
- 239000004317 sodium nitrate Substances 0.000 description 1
- 235000010344 sodium nitrate Nutrition 0.000 description 1
- 229940006186 sodium polystyrene sulfonate Drugs 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- HXJUTPCZVOIRIF-UHFFFAOYSA-N sulfolane Chemical compound O=S1(=O)CCCC1 HXJUTPCZVOIRIF-UHFFFAOYSA-N 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 229920001059 synthetic polymer Polymers 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 235000005074 zinc chloride Nutrition 0.000 description 1
- 239000011592 zinc chloride Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
- B01D71/06—Organic material
- B01D71/30—Polyalkenyl halides
- B01D71/32—Polyalkenyl halides containing fluorine atoms
- B01D71/34—Polyvinylidene fluoride
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
- B01D67/0009—Organic membrane manufacture by phase separation, sol-gel transition, evaporation or solvent quenching
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
- B01D67/0002—Organic membrane manufacture
- B01D67/0009—Organic membrane manufacture by phase separation, sol-gel transition, evaporation or solvent quenching
- B01D67/0013—Casting processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
- B01D69/02—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor characterised by their properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/08—Specific temperatures applied
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2323/00—Details relating to membrane preparation
- B01D2323/12—Specific ratios of components used
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2325/00—Details relating to properties of membranes
- B01D2325/02—Details relating to pores or porosity of the membranes
- B01D2325/022—Asymmetric membranes
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は液体の精密濾過に使用される微孔性膜の製造方
法に関する０、更に詳しくは、本発明は濾過速度の大き
い微孔性膜の製造方法に関する。Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for producing a microporous membrane used for precision filtration of liquids. Relating to a manufacturing method.
（従来の技術）
微孔性膜は古くから知られており、（例えばアール・ケ
スティング（Ｒ，Ｋｓｓｔｉｎｇ）著シンセティック・
ポリマー・メンプラン（Ｓｙｎｔｈｅｔｉｃ Ｐｏｌ
ｙｍｅｒ Ｍｅｍｂｒａｎｅ）？グロウヒル社（Ｍｃ
Ｃｒａｗ Ｈｉ１１社）発行）濾過用フィルターなど
に広く利用されている。微孔性膜は、たとえば米国特許
第１．４２１．３４１号、同３，１３３．１３２号、同
２゜９４４．０１７号、特公昭４３−１５６９８号、特
公昭４５−３３３１３号、同４８−３９５８６号、同４
８−４００５０号などに記載されているように、セルロ
ーズエステルを原料として製造されるもの、米国特許第
２．７８３．８９４号、同 。(Prior Art) Microporous membranes have been known for a long time (for example, in Synthetic Films by R, Kssting).
Synthetic Pol
ymer Membrane)? Grow Hill Company (Mc
(Published by Craw Hi 11) It is widely used in filtration filters, etc. Microporous membranes are disclosed in, for example, U.S. Pat. No. 1.421.341, U.S. Pat. No. 39586, same 4
As described in US Pat. No. 8-40050, etc., those manufactured using cellulose ester as a raw material, and US Pat. No. 2.783.894.
３．４０８，３１５号、同４，３４０．４７９号、同４
，３４０．４８０号、同４，４５０．１２６号ドイツ特
許ＤＥ３，１３８．５２５号、特開昭５Ｂ−３７８４２
号などに記載されているように脂肪族ポリアミドを原料
として製造されるもの、米国特許第４．１９６，０７０
号、同４，３４０゜４８２号、特開昭５５−９９９３４
号、特開昭５８−９１７３２号などに記載されているよ
うにポリフルオロカーボンを原料として製造されるもの
、特開昭５６−１５４０５１号、特開昭５６−８６９４
１号、特開昭５６−１２６４０号などに記載されている
ポリスルホンを原料とするもの、ドイツ特許０ＬＳ３，
００３，４００号などに記載されているポリプロピレン
を原料とするものなどがある。これら微孔性膜は電子工
業用洗浄水、医薬用水、医薬製造工程用水、食品水等の
濾過、滅菌に用いられ近年その用途と使用量は拡大して
おり、特に粒子捕捉の点から信頼性の高い微孔性膜が注
目され多用されている。3.408,315, 4,340.479, 4
, 340.480, 4,450.126, German Patent DE 3,138.525, JP-A-5B-37842
No. 4,196,070, manufactured from aliphatic polyamide as a raw material, as described in US Pat.
No. 4,340゜482, JP-A-55-99934
JP-A-56-154051, JP-A-56-8694, which are manufactured using polyfluorocarbon as a raw material as described in JP-A No. 58-91732, etc.
No. 1, those made from polysulfone described in JP-A-56-12640, etc., German patent 0LS3,
There are those made from polypropylene, such as those described in No. 003,400. These microporous membranes are used for filtration and sterilization of electronic industry cleaning water, medical water, water for pharmaceutical manufacturing processes, food water, etc., and their applications and usage have expanded in recent years, especially in terms of particle capture. Highly microporous membranes are attracting attention and are widely used.
（発明が解決しようとする問題点）
しかしながら従来の微孔性膜は、単位面積当たりの濾過
速度が十分とは言えず、必要濾過流量を得るにはより高
い圧力で濾過する必要があり、又は膜面積を増すぺ（多
くの濾過ユニットを並列して使用することを余儀無くさ
れている。そこで濾過工程のコストダウンの面で濾過速
度を上げる事は当業界の技術的課題であった。(Problems to be Solved by the Invention) However, conventional microporous membranes cannot be said to have a sufficient filtration rate per unit area, and in order to obtain the required filtration flow rate, it is necessary to filter at a higher pressure, or Increasing the membrane area (many filtration units are forced to be used in parallel) Therefore, increasing the filtration speed in order to reduce the cost of the filtration process has been a technical challenge in the industry.
このような観点から、従来微孔性腺の改質のために、出
来上がった膜をアルコール等の有機溶媒によって処理す
る事が知られており、例えば特開昭５５−１４７１０８
号には、ポリスルホン半透膜をアルコール処理し、濾過
速度を上げる方法が記載されている。しかしながらこの
方法の場合には、濾過速度の増大が膜の孔径の増大によ
るものであるために、膜が本来維持せねばならない分離
能の低下を伴い好ましくない。From this point of view, it has been known to treat the finished membrane with an organic solvent such as alcohol in order to modify the microporous glands.
The issue describes a method for increasing the filtration rate by treating polysulfone semipermeable membranes with alcohol. However, in the case of this method, since the increase in filtration rate is due to the increase in the pore size of the membrane, this is not preferable as it involves a decrease in the separation ability that the membrane should originally maintain.
そこで本発明者等は、アルコール処理が膜に与える効果
について詳細に調べた結果、アルコール処理の極く初期
には膜の空孔率が上昇し、引続き平均孔径が増大すると
いう２つの現象が存在する事を見い出し本発明に到達し
た。Therefore, the present inventors investigated in detail the effect that alcohol treatment has on membranes, and found that two phenomena exist: the porosity of the membrane increases at the very early stage of alcohol treatment, and the average pore diameter subsequently increases. The present invention was achieved by discovering the following.
従って本発明の第１の目的は、単位面積当たりの濾過流
量を増大することのできる微孔性膜の製造方法を提供す
ることにある。Therefore, a first object of the present invention is to provide a method for manufacturing a microporous membrane that can increase the filtration flow rate per unit area.
本発明の第２の目的は、微粒子、ならびに細菌等を効率
良く捕捉することができる濾過寿命の長い微孔性膜の製
造方法を提供することにある。A second object of the present invention is to provide a method for producing a microporous membrane with a long filtration life that can efficiently trap fine particles, bacteria, and the like.
（問題を解決するための手段）
本発明の上記の諸口的は、ポリマーを極性有機溶媒に溶
解してなる製膜原液を凝固浴に浸漬する微孔性膜の製造
方法において、謹製膜原液を凝固浴に浸漬し微孔を形成
した後、微孔サイズが実質的に変化しない程度にアルコ
ールで処理することを特徴とする微孔性膜の製造方法に
よって達成された。(Means for Solving the Problems) The above-mentioned aspects of the present invention are that in the method for producing a microporous membrane in which a membrane-forming stock solution obtained by dissolving a polymer in a polar organic solvent is immersed in a coagulation bath, the membrane-forming stock solution is This was achieved by a method for producing a microporous membrane characterized by immersing it in a coagulation bath to form micropores and then treating it with alcohol to the extent that the micropore size does not substantially change.
本発明で使用することのできる微孔性膜には、ポリ弗化
ビニリデン、ポリテトラフルオロエチレンの如き弗素系
樹脂、ポリスルホン、ポリエーテルスルホン、脂肪族ポ
リアミド、セルローズエステル、ポリプロピレンポリイ
ミド等の公知のポリマーを単独又は混合して原料とする
ことができる。Microporous membranes that can be used in the present invention include known polymers such as polyvinylidene fluoride, fluorine-based resins such as polytetrafluoroethylene, polysulfone, polyethersulfone, aliphatic polyamide, cellulose ester, and polypropylene polyimide. These can be used alone or in combination as raw materials.
本発明においては、これらの中でもポリスルホンが好ま
しく、特に
又は、
の繰り返し単位で表されるポリマーが好ましい。In the present invention, polysulfones are preferred among these, and polymers represented by the repeating units of or are particularly preferred.
微孔性膜の製造は、上記ポリマーを■良溶媒、■良溶媒
と非溶媒の混合溶媒又は■ポリマーに対する熔解性の程
度が異なる複数種の溶媒の混合したものに溶解して製膜
原液を作製し、これを支持体上に、又は直接凝固液中に
流延し洗浄、乾燥して行う、この場合に、ポリマーを熔
解する溶媒の一例としては、ジクロロメタンアセトン、
ジメチルホルムアミド、ジメチルアセトアミド、ジメチ
ルスルホキシド、２−ピロリドン、Ｎ−メチルー２−ピ
ロリドン、スルホラン、ヘキサメチルホスホルアミド等
を挙げることができる。To produce a microporous membrane, the above polymer is dissolved in 1) a good solvent, 2) a mixed solvent of a good solvent and a non-solvent, or 2) a mixture of multiple types of solvents with different degrees of solubility for the polymer to form a membrane-forming stock solution. In this case, examples of solvents that dissolve the polymer include dichloromethane acetone,
Dimethylformamide, dimethylacetamide, dimethylsulfoxide, 2-pyrrolidone, N-methyl-2-pyrrolidone, sulfolane, hexamethylphosphoramide and the like can be mentioned.
上記溶媒に添加する非溶媒の一例としては、セロソルブ
類、メタノール、エタノール、プロパツール、アセトン
、テトラヒドロフラン、ポリエチレングリコール、グリ
セリン等が挙げられる。非溶媒の良溶媒に対する割合は
、混合液が均一状態を保てる範囲ならばいかなる範囲で
もよいが、５重量％〜５０重量％が好ましい。Examples of nonsolvents added to the above solvent include cellosolves, methanol, ethanol, propatool, acetone, tetrahydrofuran, polyethylene glycol, glycerin, and the like. The ratio of the nonsolvent to the good solvent may be in any range as long as the mixed liquid can maintain a uniform state, but is preferably 5% to 50% by weight.
又、多孔構造を制御するものとして膨潤剤と称される無
機電解質、有機電解質、高分子電解質等を加えることも
できる。Furthermore, an inorganic electrolyte, an organic electrolyte, a polymer electrolyte, etc. called a swelling agent may be added to control the porous structure.
本発明で使用することのできる電解質としては、食塩、
硝酸ナトリウム、硝酸カリウム、硫酸ナトリウム、塩化
亜鉛等の無機酸の金属塩、酢酸ナトリウム、ギ酸ナトリ
ウム等の有機酸の金属塩、ポリスチレンスルホン酸ナト
リウム、ポリビニルベンジルトリメチルアンモニウムク
ロライド等の高分子電解質、ジオクチルスルホコハク酸
ナトリウム、アルキルメチルタウリン酸ナトリウム等の
イオン系界面活性剤等が用いられる。これらの電解質は
、単独でポリマー溶液に加えてもある程度の効果を示す
ものであるが、これら電解質を水溶液として添加する場
合には、特に顕著な効果を示すものである。電解質水溶
液の添加量は添加によって溶液の均一性が失われること
がない限り、特に制限はないが、通常、溶媒に対して０
．５容量％〜ｌＯ容量％である。又、電解質水溶液の濃
度についても特に制限はなく、濃度の大きい方が効果が
大きいが、通常用いられる濃度としては１重量％〜６０
重量％である。Electrolytes that can be used in the present invention include salt,
Metal salts of inorganic acids such as sodium nitrate, potassium nitrate, sodium sulfate, and zinc chloride, metal salts of organic acids such as sodium acetate and sodium formate, polymer electrolytes such as sodium polystyrene sulfonate, polyvinylbenzyltrimethylammonium chloride, and dioctyl sulfosuccinic acid. Ionic surfactants such as sodium and sodium alkylmethyltaurate are used. Although these electrolytes exhibit some effects even when added alone to a polymer solution, they exhibit particularly remarkable effects when added as an aqueous solution. The amount of the electrolyte aqueous solution added is not particularly limited as long as the addition does not impair the uniformity of the solution, but it is usually 0% to the solvent.
．． 5% by volume to 10% by volume. There is also no particular restriction on the concentration of the electrolyte aqueous solution, and the higher the concentration, the greater the effect, but the concentration usually used is 1% by weight to 60% by weight.
Weight%.
製膜原液としてのポリマー溶液の濃度は５〜３５重量％
、好ましくは１０〜３０重量％である。The concentration of the polymer solution as a membrane forming stock solution is 5 to 35% by weight.
, preferably 10 to 30% by weight.
３５５重量を越えると、得られる微孔性膜の透水性が実
用的な意味を持たない程小さくなり、又５重量％より低
い濃度では十分な分離能を持った微孔性膜は得られない
。If the weight exceeds 355%, the water permeability of the resulting microporous membrane becomes so low that it has no practical meaning, and if the concentration is lower than 5% by weight, a microporous membrane with sufficient separation ability cannot be obtained. .
上記のようにして調整した製膜原液を支持体の上に流延
し、流延直後或いは一定時間をおいて、凝固液中に支持
体ごとポリマー溶液膜を浸漬する。The membrane-forming stock solution prepared as described above is cast onto a support, and the polymer solution membrane together with the support is immersed in a coagulation solution immediately after casting or after a certain period of time.
凝固液としては、水が最も一般的に用いられるが、ポリ
マーを溶解しない有機溶媒を用いても良く、又これら非
溶媒を２種以上混合して用いても良い。As the coagulating liquid, water is most commonly used, but an organic solvent that does not dissolve the polymer may also be used, or a mixture of two or more of these non-solvents may be used.
支持体としては、通常微孔性膜を製造する場合に支持体
として使用できるものの中から任意に選択することがで
きるが、特に不織布を使用した場合には支持体を剥がす
必要がないので好ましい。The support can be arbitrarily selected from those that can be used as a support in the production of microporous membranes, but it is particularly preferable to use a nonwoven fabric since there is no need to peel off the support.
本発明で使用することのできる不織布はポリプロピレン
、ポリエステル、等から成る一般的なものであり、材質
の限定を受けるものではない。The nonwoven fabric that can be used in the present invention is generally made of polypropylene, polyester, etc., and is not limited in material.
本発明においては、凝固液中でポリマーが析出した流延
膜はこの後水洗、温水洗、有機溶媒洗等の代わりに、又
はこれらの洗浄工程の直後の未乾燥の状態で、微孔性腺
の孔径が実質的に変化しない程度にアルコールで処理す
る。このような処理条件は、処理温度が室温〜６０℃好
ましくは４０℃〜５５℃、処理時間は５分〜３０分好ま
しくは１０分〜２０分であり、このようなアルコール処
理の後は、８０℃以下好ましくは４０℃以下で乾燥する
。In the present invention, the cast membrane in which the polymer has precipitated in the coagulation solution is then washed with microporous glands instead of washing with water, hot water, organic solvent, etc., or in an undried state immediately after these washing steps. Treat with alcohol to the extent that the pore size does not substantially change. Such treatment conditions include a treatment temperature of room temperature to 60℃, preferably 40℃ to 55℃, treatment time of 5 minutes to 30 minutes, preferably 10 minutes to 20 minutes, and after such alcohol treatment, Drying is carried out at a temperature of 0.degree. C. or less, preferably 40.degree. C. or less.
（作用）
浸漬時間はアルコールの温度によっても異なり、実質的
な孔径変化を伴わない範囲内であれば制限はなく、長い
方が濾過流量は増大するので好ましいが、長すぎる場合
には微孔性膜の孔径が大きくなるので好ましくない。(Effect) The immersion time varies depending on the temperature of the alcohol, and there is no limit as long as it does not cause a substantial change in pore size. Longer immersion times are preferable because they increase the filtration flow rate, but if it is too long, microporous This is not preferred because the pore size of the membrane becomes large.
この場合、膜を一度乾燥状態にした後処理した場合には
空孔率増大と孔径増大は同時に起こり、濾過流量のみの
増大は実現されない。In this case, if the membrane is once dried and then subjected to post-treatment, the porosity and pore size will increase simultaneously, and only the filtration flow rate will not increase.
上記処理において使用することのできるアルコールとし
ては、例えばメタノール、エタノール、プロパツール、
イソプロパノール、ｎ−ブタノール、１ｓｏ−ブタノー
ル、ｔｅｒ−ブタノール、アミルアルコール、イソアミ
ルアルコール等を挙げることができるが、これらの中で
も、特にメタノール、エタノール、イソプロパノール及
ヒｔｅｒ−ブタノールが好ましい。Examples of alcohols that can be used in the above treatment include methanol, ethanol, propatool,
Examples include isopropanol, n-butanol, 1so-butanol, ter-butanol, amyl alcohol, isoamyl alcohol, and among these, methanol, ethanol, isopropanol, and ter-butanol are particularly preferred.
これらのアルコールは単独で使用することも、混合して
使用することも、更には、他の溶媒を少量添加して使用
することもできる。These alcohols can be used alone, in combination, or with a small amount of other solvent added.
（発明の効果）
本発明によれば、極めて容易に微孔性膜本来の分離能を
低下させることなく、微孔性膜の濾過流量を向上させる
ことができる。本発明によって得られた膜の濾過効率は
極めて大きいので、濾過流量に対する微孔性腺の寿命も
大きく改善される。(Effects of the Invention) According to the present invention, the filtration flow rate of the microporous membrane can be improved very easily without reducing the inherent separation ability of the microporous membrane. Since the filtration efficiency of the membrane obtained according to the invention is extremely high, the lifetime of the microporous glands relative to the filtration flow rate is also greatly improved.
以下、本発明を実施例に従って更に詳述するが、本発明
はこれによって限定されるものではない。EXAMPLES Hereinafter, the present invention will be explained in more detail according to Examples, but the present invention is not limited thereto.
実施例１゜
ポリフッ化ビニリデン２０部、ジメチルアセトアミド（
ＤＭＡ）７０部及びメタノール１０部よりなる混合溶液
を、ガラス板上にドクターブレードを用いて２５０μｍ
厚味に流延し、３０秒間空気中に放置した後、水／ＤＭ
Ａ＝１／１の凝固液に浸漬し、２分間凝固させて直ちに
５０℃のメタノールに１０分間浸漬させた。処理を終わ
った膜は４０℃にて乾燥させた。孔径は０．０５μ、濾
過流量は１５ｍ／／ｃｊ・ｍｉ ｎ／ａ ｔｍであった
のに対し、【タノール未処理の膜は孔径は０．０５μｍ
とメタノール処理した場合と同じであったが、濾過流量
は４ｍ１ｌ／ｃ１１・ｍｉｎ −ａ ｔｍと小さかった
。Example 1 20 parts of polyvinylidene fluoride, dimethylacetamide (
A mixed solution consisting of 70 parts of DMA) and 10 parts of methanol was heated to 250 μm on a glass plate using a doctor blade.
After casting it thickly and leaving it in the air for 30 seconds, water/DM
It was immersed in a coagulating solution of A=1/1, coagulated for 2 minutes, and immediately immersed in methanol at 50° C. for 10 minutes. The treated membrane was dried at 40°C. The pore size was 0.05 μm and the filtration flow rate was 15 m//cj・min/a tm;
was the same as when treated with methanol, but the filtration flow rate was as small as 4 ml/c11·min -a tm.
一方、メタノール処理を３時間行った場合には１８ｍｊ
！／ｄ−ｍｉｎ−ａｔｍの濾過流量であったが、孔径も
０．９２μと拡大しているのが観察され、分離能力が劣
化したことが確認された。これらの事実は、本発明の方
法によって初めて、分離能力を劣化させることなく濾過
流量を大きくすることができることを実証するものであ
る。On the other hand, when methanol treatment was performed for 3 hours, 18 mj
! The filtration flow rate was /d-min-atm, but the pore diameter was also observed to be enlarged to 0.92μ, confirming that the separation ability had deteriorated. These facts demonstrate that, for the first time, the method of the present invention makes it possible to increase the filtration flow rate without deteriorating the separation ability.
実施例２゜
ポリスルホン（ＵＣＣ社Ｐ３５００）２０部、Ｎメチル
−２−ピロリドン６０部、ポリビニルピロリドン（分子
量４万）１５部及びＬｉＣ１５部よりなる均一溶液をガ
ラス板上に１５０μ厚に流延した後直ちに冷水に浸漬し
、１分後、イソプロパノール（５０℃）に８分間浸漬処
理を行った。Example 2 A homogeneous solution consisting of 20 parts of polysulfone (UCC P3500), 60 parts of N-methyl-2-pyrrolidone, 15 parts of polyvinylpyrrolidone (molecular weight 40,000) and 15 parts of LiC was cast onto a glass plate to a thickness of 150μ. Immediately, it was immersed in cold water, and after 1 minute, it was immersed in isopropanol (50°C) for 8 minutes.
この膜はＯ，ｌＩＩｍ孔径を有し、濾過流量５０ｍｊ！
／ｃｊ−ｍｉ ｎ −ａ ｔｍであったのに対し、イソ
プロパノール未処理の膜は０．１μｍ孔径で２７ｍ７！
／−・ｍ ｉ ｎ −ａ ｔ ｍであった。一方、３時
間上記のアルコール処理を行った場合には、濾過流量が
５２ｍｊ！／ａｄ−ｍｉｎ−ａｔｍと増大したが、同時
に孔径も０．１６μｍと増大し分離能が低下したことが
確認された。This membrane has a pore size of O,lIIm and a filtration flow rate of 50 mj!
/cj-min-a tm, whereas the membrane untreated with isopropanol had a pore size of 0.1 μm and 27 m7!
/-・min-atm. On the other hand, when the above alcohol treatment was performed for 3 hours, the filtration flow rate was 52 mj! /ad-min-atm, but at the same time, the pore diameter also increased to 0.16 μm, and it was confirmed that the separation ability decreased.
Claims (1)
凝固浴に浸漬する微孔性膜の製造方法において、該製膜
原液を凝固浴に浸漬し微孔を形成した後、微孔サイズが
実質的に変化しない程度にアルコールで処理することを
特徴とする微孔性膜の製造方法。 ２）ポリマーが芳香族ポリスルホンであることを特徴と
する特許請求の範囲第１項に記載の微孔性膜の製造方法
。 ３）アルコールがメタノール、エタノール、イソプロパ
ノール又はｔｅｒ−ブタノールである特許請求の範囲第
１項に記載の微孔性膜の製造方法。[Claims] 1) A method for producing a microporous membrane in which a membrane-forming stock solution prepared by dissolving a polymer in a polar organic solvent is immersed in a coagulation bath, in which the film-forming stock solution is immersed in a coagulation bath to form micropores. A method for producing a microporous membrane, which comprises treating the membrane with alcohol to the extent that the micropore size does not substantially change. 2) The method for producing a microporous membrane according to claim 1, wherein the polymer is aromatic polysulfone. 3) The method for producing a microporous membrane according to claim 1, wherein the alcohol is methanol, ethanol, isopropanol, or ter-butanol.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60155722A JPS6214905A (en) | 1985-07-15 | 1985-07-15 | Process of manufacturing microporous |
| GB8701193A GB2199786B (en) | 1985-07-15 | 1987-01-20 | Polymeric micro-porous membranes and their production |
| DE19873701633 DE3701633A1 (en) | 1985-07-15 | 1987-01-21 | MICROPOROUS MEMBRANE |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60155722A JPS6214905A (en) | 1985-07-15 | 1985-07-15 | Process of manufacturing microporous |
| GB8701193A GB2199786B (en) | 1985-07-15 | 1987-01-20 | Polymeric micro-porous membranes and their production |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6214905A true JPS6214905A (en) | 1987-01-23 |
| JPH057047B2 JPH057047B2 (en) | 1993-01-28 |
Family
ID=39339878
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60155722A Granted JPS6214905A (en) | 1985-07-15 | 1985-07-15 | Process of manufacturing microporous |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPS6214905A (en) |
| DE (1) | DE3701633A1 (en) |
| GB (1) | GB2199786B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109847585A (en) * | 2018-12-20 | 2019-06-07 | 时代沃顿科技有限公司 | The preparation method of composite nanometer filtering film and composite nanometer filtering film prepared therefrom |
Families Citing this family (26)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3850493T2 (en) * | 1987-11-06 | 1995-02-09 | Dow Chemical Co | SEMI-PLEASANT MEMBRANE WITH AN INNER DISCRIMINATING ZONE. |
| DE3829752A1 (en) * | 1988-09-01 | 1990-03-22 | Akzo Gmbh | INTEGRAL ASYMMETRICAL POLYAETHERSULPHONE MEMBRANE, METHOD FOR THE PRODUCTION AND USE FOR ULTRAFILTRATION AND MICROFILTRATION |
| US4902422A (en) * | 1988-12-06 | 1990-02-20 | Board Regents The University Of Texas System | Defect-free ultrahigh flux asymmetric membranes |
| US5324538A (en) * | 1991-03-12 | 1994-06-28 | Toray Industries, Inc. | Process for producing composite semipermeable membrane employing a polyfunctional amine solution and high flash point - solvent |
| US5188734A (en) * | 1991-03-26 | 1993-02-23 | Memtec America Corporation | Ultraporous and microporous integral membranes |
| US5480554A (en) * | 1992-05-13 | 1996-01-02 | Pall Corporation | Integrity-testable wet-dry-reversible ultrafiltration membranes and method for testing same |
| ES2138877B1 (en) * | 1994-03-04 | 2000-09-01 | Memtec America Corp | SYNTHETIC POLYMER MEMBRANES WITH LARGE PORES. |
| US6277281B1 (en) * | 1994-03-04 | 2001-08-21 | Usf Filtration And Separations Group Inc. | Large pore synthetic polymer membranes |
| DE4421871C2 (en) * | 1994-06-23 | 1997-06-19 | Seitz Filter Werke | Multi-layer microfiltration membrane with integrated pre-filter layer and process for its production |
| ATE358574T1 (en) * | 1996-01-22 | 2007-04-15 | Pall Corp | METHOD FOR PRODUCING A HIGHLY POROUS MEMBRANE FROM POLYVINYLIDED DIFLUORIDE |
| WO1998021588A1 (en) * | 1996-11-14 | 1998-05-22 | Pall Corporation | Membrane and methods of preparing and using same |
| US6045899A (en) | 1996-12-12 | 2000-04-04 | Usf Filtration & Separations Group, Inc. | Highly assymetric, hydrophilic, microfiltration membranes having large pore diameters |
| US6146747A (en) * | 1997-01-22 | 2000-11-14 | Usf Filtration And Separations Group Inc. | Highly porous polyvinylidene difluoride membranes |
| US5958989A (en) * | 1997-07-08 | 1999-09-28 | Usf Filtration And Separations Group, Inc. | Highly asymmetric ultrafiltration membranes |
| ES2151815B1 (en) * | 1998-05-18 | 2001-08-16 | Consejo Superior Investigacion | PROCEDURE FOR THE PREPARATION OF CARBON MEMBRANES FOR THE SEPARATION OF PERMANENT GASES. |
| AT408656B (en) * | 1998-06-04 | 2002-02-25 | Chemiefaser Lenzing Ag | METHOD FOR PRODUCING CELLULOSIC MOLDED BODIES |
| JP4038049B2 (en) * | 2000-05-24 | 2008-01-23 | ミリポア・コーポレイション | Method for forming multilayer structure |
| EP1534755B1 (en) | 2002-05-10 | 2011-10-12 | Bio-Layer Pty Limited | Generation of surface coating diversity |
| EP1700244A4 (en) | 2003-12-12 | 2009-07-08 | Bio Layer Pty Ltd | A method for designing surfaces |
| AU2005259833B2 (en) | 2004-07-02 | 2011-09-22 | Anteo Technologies Pty Ltd | Use of metal complexes |
| EP1721657A1 (en) * | 2005-05-13 | 2006-11-15 | SONY DEUTSCHLAND GmbH | A method of fabricating a polymeric membrane having at least one pore |
| FR2958190B1 (en) * | 2010-04-01 | 2012-05-18 | Commissariat Energie Atomique | PROCESS FOR FORMING VINYLIDENE POLYFLUORIDE-TYPE FLUORINE POLYMER FILM USED AS LITHIUM BATTERY SEPARATOR |
| DE102011114634A1 (en) | 2011-10-04 | 2013-04-04 | Mn-Beteiligungs Gmbh | Abrasion resistant membrane and process for its preparation |
| TWI658070B (en) * | 2013-11-14 | 2019-05-01 | 美商恩特葛瑞斯股份有限公司 | Microporous polyamide-imide membranes |
| DE102018004521A1 (en) | 2018-06-07 | 2019-12-12 | Sartorius Stedim Biotech Gmbh | Serial arrangement with multiple layers of asymmetric filter media, manufacturing process, filtration unit, use of the array, and characterization procedures |
| EP3933023A4 (en) * | 2019-03-14 | 2022-09-28 | Teijin Limited | Membrane for concentrating biological particles, concentrating device, concentrating system, concentrating method, and method for detecting biological particles |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50756A (en) * | 1973-05-02 | 1975-01-07 | ||
| JPS5382669A (en) * | 1976-12-29 | 1978-07-21 | Kuraray Co Ltd | Preparation of dry separating membrane |
-
1985
- 1985-07-15 JP JP60155722A patent/JPS6214905A/en active Granted
-
1987
- 1987-01-20 GB GB8701193A patent/GB2199786B/en not_active Expired - Lifetime
- 1987-01-21 DE DE19873701633 patent/DE3701633A1/en not_active Withdrawn
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50756A (en) * | 1973-05-02 | 1975-01-07 | ||
| JPS5382669A (en) * | 1976-12-29 | 1978-07-21 | Kuraray Co Ltd | Preparation of dry separating membrane |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109847585A (en) * | 2018-12-20 | 2019-06-07 | 时代沃顿科技有限公司 | The preparation method of composite nanometer filtering film and composite nanometer filtering film prepared therefrom |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2199786A (en) | 1988-07-20 |
| JPH057047B2 (en) | 1993-01-28 |
| DE3701633A1 (en) | 1988-08-04 |
| GB2199786B (en) | 1990-03-28 |
| GB8701193D0 (en) | 1987-02-25 |
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