JP2001038173A - Dehumidifying membrane and production of dehumidifying membrane - Google Patents

Dehumidifying membrane and production of dehumidifying membrane

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Publication number
JP2001038173A
JP2001038173A JP11221635A JP22163599A JP2001038173A JP 2001038173 A JP2001038173 A JP 2001038173A JP 11221635 A JP11221635 A JP 11221635A JP 22163599 A JP22163599 A JP 22163599A JP 2001038173 A JP2001038173 A JP 2001038173A
Authority
JP
Japan
Prior art keywords
thin film
film
dehumidifying
water vapor
organic polymer
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.)
Withdrawn
Application number
JP11221635A
Other languages
Japanese (ja)
Inventor
Tomonari Saito
知成 斎藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nok Corp
Original Assignee
Nok Corp
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Filing date
Publication date
Application filed by Nok Corp filed Critical Nok Corp
Priority to JP11221635A priority Critical patent/JP2001038173A/en
Publication of JP2001038173A publication Critical patent/JP2001038173A/en
Withdrawn legal-status Critical Current

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  • Separation Using Semi-Permeable Membranes (AREA)
  • Drying Of Gases (AREA)

Abstract

PROBLEM TO BE SOLVED: To improve the tolerance and film strength of a dehumidifying membrane, to suppress permeation of air and to maintain excellent removing performance of water vapor by laminating a hydrophilic organic polymer material in a thin film state on the surface of a porous base body having micropores. SOLUTION: The dehumidifying membrane 1 is produced by laminating a chitosan thin film 3 as a hydrophilic organic polymer material on the surface of a porous alumina hollow fiber 2. The chitosan thin film 3 is formed as a homogeneous and dense thin film layer on the surface of the porous alumina hollow fiber 2 so as to use such a phenomenon that the thin film layer in contact with water vapor dissolves and diffuse moisture to separate as well as to secondarily use the capillary condensation phenomenon of moisture in the pores of the thin film. The pore diameter of the micropore is specified to <=5 μm. Thereby, the tolerance and film strength of the dehumidifying membrane 1 against a mist component such as oil in air can be improved and permeation of air is suppressed to maintain excellent removing performance for water vapor.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、除湿膜及び除湿膜
の製造方法に関する。
The present invention relates to a dehumidifying film and a method for producing the dehumidifying film.

【0002】[0002]

【従来の技術】これまで工業生産などに用いられる空気
(例えば圧縮空気)の除湿には、冷凍機式や吸着式など
の除湿機が多く利用されてきたが、環境保全を図る為に
冷凍機等で使用されるフロン等の冷媒の撤廃や、コスト
及びメンテナンスの有利さから、近年では膜式ドライヤ
ーの利用が注目されている。
2. Description of the Related Art Hitherto, dehumidifiers of the refrigerator type or adsorption type have been widely used for dehumidifying air (for example, compressed air) used in industrial production and the like. In recent years, attention has been paid to the use of a membrane dryer because of the elimination of refrigerants such as chlorofluorocarbons and the advantages of cost and maintenance.

【0003】膜式ドライヤーは、水蒸気を含む空気を膜
に供給し、膜を介して水蒸気のみを分離除去し、乾燥空
気を得るものである。
[0003] The membrane dryer supplies air containing water vapor to the membrane, and separates and removes only water vapor through the membrane to obtain dry air.

【0004】この場合用いられる膜としては、水蒸気を
溶解・拡散機構によって透過する高分子系の均質膜が主
流であるが、この場合に、水蒸気の膜透過性は、水蒸気
の膜への溶解性と拡散性によって決まり、親水性が高
く、かつ膜厚の薄い膜ほど水蒸気の透過性に優れてい
る。
As a membrane used in this case, a polymer-based homogeneous membrane that transmits water vapor by a dissolution / diffusion mechanism is mainly used. In this case, the water vapor permeability of the film is determined by the solubility of the water vapor in the film. The film having a higher hydrophilicity and a smaller thickness has a higher water vapor permeability.

【0005】[0005]

【発明が解決しようとする課題】このような高分子系の
均質膜においては、用いる膜によって、空気中に含まれ
る油等のミスト成分に対する耐性や膜強度あるいは水蒸
気の除去性能が低いことなどが問題点として挙げられ
る。
In such a polymer-based homogeneous membrane, depending on the membrane used, resistance to mist components such as oil contained in air, membrane strength, or performance of removing water vapor is low. This is a problem.

【0006】これに対し、微細孔径を有するセラミック
ス(アルミナ)多孔質膜は、異物への耐性や膜強度を期
待することは可能であるが、一般的に用いられる細孔径
が0.2μm程度までの多孔質膜では細孔内での水の毛
管凝縮が生じず、空気も水蒸気も透過してしまうことに
なり、水蒸気の選択透過性を得ることは困難とされてい
る。
On the other hand, a ceramic (alumina) porous film having a fine pore diameter can be expected to have resistance to foreign substances and film strength, but generally has a pore diameter of about 0.2 μm. In the porous membrane described above, capillary condensation of water in the pores does not occur, and both air and water vapor permeate, and it is difficult to obtain selective permeability of water vapor.

【0007】そこで、これまで除湿膜として用いられて
いる高分子系の均質膜に対して耐性や強度を持たせよう
とすると、膜全体が同一の素材で形成された均質膜であ
るため、膜厚をある程度厚くする必要があり、水蒸気の
透過性が損なわれるという問題があった。
In order to impart resistance and strength to a polymer-based homogeneous film which has been used as a dehumidifying film, since the entire film is a homogeneous film formed of the same material, It is necessary to increase the thickness to some extent, and there is a problem that water vapor permeability is impaired.

【0008】本発明は上記従来技術の問題を解決するた
めになされたもので、その目的とするところは、耐性や
膜強度を備えると共に、空気の透過を抑えて高い水蒸気
の除去性能を有することの可能な除湿膜及び除湿膜の製
造方法を提供することにある。
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a film having resistance and film strength, and having high water vapor removal performance by suppressing air permeation. To provide a dehumidifying film and a method for producing the dehumidifying film.

【0009】[0009]

【課題を解決するための手段】上記目的を達成するため
に本発明の除湿膜にあっては、微細孔を有する多孔質基
材の表面に、親水性の有機系高分子物質を薄膜状態で積
層させたことを特徴とする。
In order to achieve the above object, in the dehumidifying film of the present invention, a hydrophilic organic polymer substance is formed in a thin film state on a surface of a porous substrate having fine pores. It is characterized by being laminated.

【0010】これにより、多孔質基材の表面に薄膜状態
で積層された親水性の有機系高分子物質は、空気を透過
させず、水蒸気を親水性の有機系高分子物質の薄膜層に
溶解・拡散させて水蒸気の選択透過性を得ることができ
る。
As a result, the hydrophilic organic polymer material laminated in a thin film state on the surface of the porous substrate does not allow air to permeate, and dissolves water vapor in the hydrophilic organic polymer material thin film layer. It can be diffused to obtain water vapor selective permeability.

【0011】前記親水性の有機系高分子物質は、キトサ
ンであることが好適である。
It is preferable that the hydrophilic organic polymer is chitosan.

【0012】前記親水性の有機系高分子物質は、キチン
またはセルロース類であることが好適である。
It is preferable that the hydrophilic organic polymer is chitin or cellulose.

【0013】前記多孔質基材の微細孔の孔径は、5μm
以下であることが好適である。
[0013] The pore size of the fine pores of the porous substrate is 5 µm
It is preferred that:

【0014】前記多孔質基材は、多孔質セラミックス中
空糸であることが好適である。
The porous substrate is preferably a porous ceramic hollow fiber.

【0015】また、除湿膜の製造方法にあっては、微細
孔を有する多孔質基材を浴媒中に親水性の有機系高分子
物質を溶解させた製膜溶液に浸漬し、乾燥することによ
り、微細孔を有する多孔質基材の表面に、親水性の有機
系高分子物質を薄膜状態で積層させる。
In the method for producing a dehumidifying film, a porous substrate having fine pores is immersed in a film forming solution in which a hydrophilic organic polymer substance is dissolved in a bath medium and dried. Thereby, a hydrophilic organic polymer substance is laminated in a thin film state on the surface of the porous substrate having micropores.

【0016】[0016]

【発明の実施の形態】以下に発明の詳細を説明する。親
水性の有機系高分子物質を積層する多孔質基材として
は、例えばアルミナ、シリカ、炭素などの多孔質セラミ
ックスが挙げられるが、その孔径は大きすぎると積層し
たキトサン薄膜の気密性や耐圧性が損なわれるので、5
μm以下、好ましくは0.5μm以下のものが用いられ
る。多孔質セラミックスは、オイル等の耐性と強度を兼
ね備えている。
DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below. Examples of the porous substrate on which the hydrophilic organic polymer material is laminated include porous ceramics such as alumina, silica, and carbon. However, if the pore size is too large, the airtightness and pressure resistance of the laminated chitosan thin film will be considered. Is impaired, so 5
μm or less, preferably 0.5 μm or less is used. Porous ceramics have both resistance to oil and the like and strength.

【0017】多孔質基材の形態は、中空糸状とすること
で膜面積を大きくすることができ、また分離された水蒸
気成分は管内を通して除去することが可能となる。しか
しながら中空糸状に限定されるものではなく、シート状
でも良いことはもちろんである。
The porous substrate can be formed into a hollow fiber to increase the membrane area, and the separated water vapor component can be removed through a tube. However, the shape is not limited to the hollow fiber shape, but may be a sheet shape.

【0018】また、親水性の有機系高分子物質は、例え
ばキトサンを溶解した製膜溶液を多孔質基材上にデイッ
ピング、または多孔質基材を製膜溶液に浸漬し、これを
乾燥することによって得られる。
The hydrophilic organic polymer substance is prepared, for example, by dipping a film-forming solution in which chitosan is dissolved on a porous substrate, or immersing the porous substrate in the film-forming solution and drying it. Obtained by

【0019】しかし、その膜厚は、薄すぎると気密性や
耐圧性が掲なわれ、厚すぎると水蒸気の透過性が低下す
るので、0.5μmから20μm、好ましくは1μmか
ら5μmとする。
However, if the film thickness is too small, the airtightness and pressure resistance are described, and if the film thickness is too thick, the permeability of water vapor is reduced. Therefore, the film thickness is 0.5 μm to 20 μm, preferably 1 μm to 5 μm.

【0020】親水性の有機系高分子物質の膜厚をコント
ロールする場合に、製膜溶液の濃度調整を行ない、浸漬
及び乾燥工程を複数回繰り返して目的とする膜厚を得る
ことも可能である。
When controlling the film thickness of the hydrophilic organic polymer substance, it is possible to adjust the concentration of the film-forming solution and repeat the immersion and drying steps a plurality of times to obtain the desired film thickness. .

【0021】尚、多孔質基材上に積層する親水性の有機
系高分子物質としては、後述する実施例ではキトサンを
選択採用しているが、この他に塩基性多糖類、またキチ
ンやセルロース類を選択採用することも可能である。
As the hydrophilic organic polymer material laminated on the porous substrate, chitosan is selected and employed in the examples described later. In addition, basic polysaccharides, chitin and cellulose are also used. It is also possible to select and adopt a class.

【0022】図1(a)は得られた除湿膜1の断面構成
を模式的に示した図であり、図1(b)は図1(a)の
D1部を拡大した図である。2は多孔質基材としての多
孔質アルミナ中空糸であり、3は多孔質アルミナ中空糸
1の表面に積層された親水性の有機系高分子物質として
のキトサン薄膜である。
FIG. 1A is a diagram schematically showing a sectional configuration of the obtained dehumidifying film 1, and FIG. 1B is an enlarged view of a portion D1 in FIG. 1A. Reference numeral 2 denotes a porous alumina hollow fiber as a porous substrate, and reference numeral 3 denotes a chitosan thin film as a hydrophilic organic polymer substance laminated on the surface of the porous alumina hollow fiber 1.

【0023】キトサン薄膜3は、多孔質アルミナ中空糸
2の膜表面に均質で緻密な薄膜層として形成され、主に
水蒸気に触れた薄膜層に水分を溶解・拡散させて分離を
行なう現象を利用し、また薄膜の細孔内での水分の毛管
凝縮現象も二次的に利用している。除湿膜1の詳細につ
いては、以下の実施例において説明する。
The chitosan thin film 3 is formed as a uniform and dense thin film layer on the surface of the porous alumina hollow fiber 2 and utilizes a phenomenon in which water is dissolved and diffused into the thin film layer mainly exposed to water vapor to perform separation. In addition, the phenomenon of capillary condensation of water in the pores of the thin film is secondarily used. Details of the dehumidifying film 1 will be described in the following examples.

【0024】(実施例1)浴媒として5%酢酸水溶液に
1.5%のキトサンを溶解した製膜溶液を孔径が0.2
μmの多孔質アルミナ中空糸(外径=2.2mm、内径
=1.8mm)にデイプコーティングし、これを室温雰
囲気下で乾燥して、キトサン薄膜を調製した。このとき
のキトサン薄膜の膜厚は、約3μmであった。
Example 1 A film-forming solution in which 1.5% chitosan was dissolved in a 5% acetic acid aqueous solution as a bath medium had a pore diameter of 0.2%.
A porous alumina hollow fiber having a diameter of μm (outer diameter = 2.2 mm, inner diameter = 1.8 mm) was deep-coated, and dried in a room temperature atmosphere to prepare a chitosan thin film. At this time, the thickness of the chitosan thin film was about 3 μm.

【0025】この除湿膜の除湿性能を以下の条件にて測
定した.膜有効長=10cm、飽和水蒸気を含有した湿
潤空気の膜管内への供給流量=200cm3/cm2・s
ec、除湿膜の水蒸気透過側(除湿膜の外周側)に流す
乾燥したスイープ空気流量=35cm3/cm2・se
c、印加圧力=120kPaである。
The dehumidifying performance of this dehumidifying film was measured under the following conditions. Effective membrane length = 10 cm, supply flow rate of wet air containing saturated steam into the membrane tube = 200 cm 3 / cm 2 · s
ec, dry sweep air flow rate flowing on the water vapor permeable side of the dehumidifying film (outer peripheral side of the dehumidifying film) = 35 cm 3 / cm 2 · se
c, applied pressure = 120 kPa.

【0026】その結果、このときの水蒸気除去率(=除
湿膜を透過した水蒸気量/供給した全水蒸気量)は約3
3%であった。
As a result, the water vapor removal rate at this time (= the amount of water vapor transmitted through the dehumidifying membrane / the total amount of supplied water vapor) is about 3
3%.

【0027】また、この除湿膜について、窒素ガス透過
速度を測定した結果、約1×10-6cm3/cm2・se
c・cmHgであり、高い水蒸気の選択透過性を示し
た。
The nitrogen gas permeation rate of the dehumidifying film was measured to be about 1 × 10 −6 cm 3 / cm 2 · sec.
c · cmHg, indicating high water vapor permselectivity.

【0028】また、この除湿膜の透過性能は、1500
kPaまでの加圧条件においても変化は見られなかっ
た。
The permeability of the dehumidifying membrane is 1500
No change was observed even under pressurized conditions up to kPa.

【0029】尚、キトサン薄膜を積層する前のこの多孔
質アルミナ中空糸単体では、窒素ガス透過速度が1×1
-1cm3/cm2・sec・cmHg以上の値を示し、
水蒸気の選択透過性は見られなかった。
The porous alumina hollow fiber alone before laminating the chitosan thin film had a nitrogen gas permeation rate of 1 × 1.
0 -1 cm 3 / cm 2 · sec · cmHg shows the above value,
No selective permeation of water vapor was observed.

【0030】(実施例2)5%酢酸水溶液に1%のキト
サンを溶解した製膜溶液を用い、実施例1と同様に、キ
トサン薄膜を調製した。
Example 2 A chitosan thin film was prepared in the same manner as in Example 1 except that a film-forming solution in which 1% of chitosan was dissolved in a 5% acetic acid aqueous solution was used.

【0031】このときのキトサン薄膜の膜厚は、約1μ
mであった。また、この除湿膜の水蒸気除去率は約45
%であり、窒素ガス透過速度は約1×10-5cm3/c
2・sec・cmHgであった。
At this time, the thickness of the chitosan thin film is about 1 μm.
m. The water vapor removal rate of the dehumidifying film is about 45.
%, And the nitrogen gas permeation rate is about 1 × 10 −5 cm 3 / c
m 2 · sec · cmHg.

【0032】[0032]

【発明の効果】上記のように説明された本発明による
と、空気透過性を抑え、高い水蒸気の選択透過性を備え
た除湿膜が得られた。
According to the present invention described above, a dehumidifying membrane having a reduced air permeability and a high water vapor selective permeability can be obtained.

【図面の簡単な説明】[Brief description of the drawings]

【図1】図1は除湿膜の断面構成を模式的に説明する図
である。
FIG. 1 is a diagram schematically illustrating a cross-sectional configuration of a dehumidifying film.

【符号の説明】[Explanation of symbols]

1 除湿膜 2 多孔質アルミナ中空糸 3 キトサン薄膜 1 Dehumidifying film 2 Porous alumina hollow fiber 3 Chitosan thin film

───────────────────────────────────────────────────── フロントページの続き Fターム(参考) 4D006 GA41 HA22 KE01P KE02P MA02 MA06 MA22 MA33 MB03 MB06 MB16 MC03X MC09 MC10X MC11 NA46 PA01 PB17 PB65 PC72 4D052 AA01 EA02 GA03 GB01 GB03 GB04  ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 4D006 GA41 HA22 KE01P KE02P MA02 MA06 MA22 MA33 MB03 MB06 MB16 MC03X MC09 MC10X MC11 NA46 PA01 PB17 PB65 PC72 4D052 AA01 EA02 GA03 GB01 GB03 GB04

Claims (6)

【特許請求の範囲】[Claims] 【請求項1】 微細孔を有する多孔質基材の表面に、親
水性の有機系高分子物質を薄膜状態で積層させたことを
特徴とする除湿膜。
1. A dehumidifying film characterized in that a hydrophilic organic polymer substance is laminated in a thin film state on a surface of a porous substrate having fine pores.
【請求項2】 前記親水性の有機系高分子物質は、キト
サンであることを特徴とする請求項1に記載の除湿膜。
2. The dehumidifying membrane according to claim 1, wherein the hydrophilic organic polymer substance is chitosan.
【請求項3】 前記親水性の有機系高分子物質は、キチ
ンまたはセルロース類であることを特徴とする請求項1
に記載の除湿膜。
3. The method according to claim 1, wherein the hydrophilic organic polymer is chitin or cellulose.
2. The dehumidifying film according to 1.
【請求項4】 前記多孔質基材の微細孔の孔径は、5μ
m以下であることを特徴とする請求項1乃至3のいずれ
か1項に記載の除湿膜。
4. The pore size of the fine pores of the porous substrate is 5 μm.
The dehumidifying film according to any one of claims 1 to 3, wherein m is not more than m.
【請求項5】 前記多孔質基材は、多孔質セラミックス
中空糸であることを特徴とする請求項4に記載の除湿
膜。
5. The dehumidifying membrane according to claim 4, wherein the porous substrate is a porous ceramic hollow fiber.
【請求項6】 微細孔を有する多孔質基材を浴媒中に親
水性の有機系高分子物質を溶解させた製膜溶液に浸漬
し、乾燥することにより、微細孔を有する多孔質基材の
表面に、親水性の有機系高分子物質を薄膜状態で積層さ
せたことを特徴とする除湿膜の製造方法。
6. A porous substrate having fine pores, which is immersed in a film forming solution in which a hydrophilic organic polymer substance is dissolved in a bath medium and dried. A method for producing a dehumidifying film, characterized in that a hydrophilic organic polymer substance is laminated in a thin-film state on the surface of (1).
JP11221635A 1999-08-04 1999-08-04 Dehumidifying membrane and production of dehumidifying membrane Withdrawn JP2001038173A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11221635A JP2001038173A (en) 1999-08-04 1999-08-04 Dehumidifying membrane and production of dehumidifying membrane

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11221635A JP2001038173A (en) 1999-08-04 1999-08-04 Dehumidifying membrane and production of dehumidifying membrane

Publications (1)

Publication Number Publication Date
JP2001038173A true JP2001038173A (en) 2001-02-13

Family

ID=16769871

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
JP (1) JP2001038173A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010501065A (en) * 2006-08-14 2010-01-14 ナノキャップ テクノロジーズ リミテッド ライアビリティ カンパニー Universal dehumidification process and equipment
RU2567922C1 (en) * 2014-05-21 2015-11-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Юго-Западный государственный университет" (ЮЗГУ) Shell-and-tube capillary condenser
JP2019042710A (en) * 2017-09-06 2019-03-22 国立大学法人 名古屋工業大学 Separation membrane

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010501065A (en) * 2006-08-14 2010-01-14 ナノキャップ テクノロジーズ リミテッド ライアビリティ カンパニー Universal dehumidification process and equipment
RU2567922C1 (en) * 2014-05-21 2015-11-10 Федеральное государственное бюджетное образовательное учреждение высшего образования "Юго-Западный государственный университет" (ЮЗГУ) Shell-and-tube capillary condenser
JP2019042710A (en) * 2017-09-06 2019-03-22 国立大学法人 名古屋工業大学 Separation membrane
JP7065492B2 (en) 2017-09-06 2022-05-12 国立大学法人 名古屋工業大学 Separation membrane

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