Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
  • B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
  • B29C41/12—Spreading-out the material on a substrate, e.g. on the surface of a liquid
• • 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
  • B01D67/0016—Coagulation
• • 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
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
  • B29C41/24—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of indefinite length
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D7/00—Producing flat articles, e.g. films or sheets
  • B29D7/01—Films or sheets
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/18—Manufacture of films or sheets
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
  • C08J9/28—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum
• • 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
  • B01D2325/0283—Pore size
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2325/00—Details relating to properties of membranes
  • B01D2325/04—Characteristic thickness
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2325/00—Details relating to properties of membranes
  • B01D2325/20—Specific permeability or cut-off range
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2079/00—Use of polymers having nitrogen, with or without oxygen or carbon only, in the main chain, not provided for in groups B29K2061/00 - B29K2077/00, as moulding material
  • B29K2079/08—PI, i.e. polyimides or derivatives thereof
  • B29K2079/085—Thermoplastic polyimides, e.g. polyesterimides, PEI, i.e. polyetherimides, or polyamideimides; Derivatives thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
  • B29K2105/04—Condition, form or state of moulded material or of the material to be shaped cellular or porous
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
  • B29K2995/0037—Other properties
  • B29K2995/0068—Permeability to liquids; Adsorption
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/755—Membranes, diaphragms
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/249921—Web or sheet containing structurally defined element or component
  • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/249921—Web or sheet containing structurally defined element or component
  • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
  • Y10T428/249955—Void-containing component partially impregnated with adjacent component
  • Y10T428/249958—Void-containing component is synthetic resin or natural rubbers
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/249921—Web or sheet containing structurally defined element or component
  • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
  • Y10T428/249961—With gradual property change within a component
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/249921—Web or sheet containing structurally defined element or component
  • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
  • Y10T428/249978—Voids specified as micro
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/249921—Web or sheet containing structurally defined element or component
  • Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
  • Y10T428/249978—Voids specified as micro
  • Y10T428/249979—Specified thickness of void-containing component [absolute or relative] or numerical cell dimension

Definitions

• the present invention relates to a porous film having substantially no skin layer (dense layer) on the surface and having a large number of continuous micropores formed thereon.
• This porous film can be obtained by using a membrane separation technology such as microfiltration and separation / concentration, or by using the pore characteristics as it is, or by filling the pores with a functional material to form a battery separator, electrolytic capacitor, It can be used as a wide range of substrate materials such as road substrates. Background art
• a polymer compound such as an amide-based polymer, a imide-based polymer, a sulfone-based polymer, a fluorine-based polymer, or an olefin-based polymer has been known.
• a method for producing a porous film made of such a material for example, a method (phase inversion method) in which a mixed solution containing the above-mentioned polymer compound is cast into a film and then guided to a coagulation solution is known. I have.
• a skin layer (dense layer) is present on the surface of the film produced by the above-mentioned method using the above-mentioned polymer compound as a material, and substantially no pores are present.
• a porous film made of an imid-based polymer a porous film made of polyimide and a method for producing the same have been disclosed (for example, Japanese Patent Application Laid-Open No. 2001-676643, See Japanese Patent Application Laid-Open No. 2000-14505826 and Japanese Patent Application Laid-Open No. 2000-314924.) These are solvent replacement rate adjusting materials for forming holes in the surface.
• the production process is complicated and that the material does not have a sufficient porosity and permeability. Disclosure of the invention
• the inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, using a polymer and a substrate in which the difference between the surface tension of the polymer and the surface tension of the substrate is a specific value or more, the polymer contains By casting the mixed solution in a film form on the substrate and inverting the phase, a porous film having a high porosity and uniform micropores can be obtained on the film surface on the side in contact with the substrate.
• the present invention has been completed.
• a method for producing a porous film to be used is provided.
• the method of the present invention includes, for example, a polymer component constituting a porous film, 8 to 25% by weight, a water-soluble polymer, 10 to 50% by weight, water, 0 to 10% by weight, a water-soluble polar solvent, 30 to 8%.
• a method of casting a 2% by weight mixed solution as a polymer solution on a substrate in the form of a film, guiding the mixture to a coagulating liquid, and inverting the phase to obtain a porous film may be used.
• the film is cast, the film is kept in an atmosphere having a relative humidity of 70 to 100% and a temperature of 15 to 90 ° C for 0.2 to 15 minutes.
• a guiding step may be included.
• the present invention relates to a porous film having a large number of interconnected micropores, wherein the thickness of the film is 5 to 200 ⁇ m, and the average pore diameter of the surface is 0.00 on both surfaces of the film. 1 to 1 ⁇ ⁇ ⁇ , average pore diameter on surface ⁇ and average pore diameter inside
• the ratio A / B to B is 0.3 to 3
• the ratio C / D of the average open area ratio C on the surface to the average open area ratio D on the inside is 0.7 to 1.5.
• the present invention provides a porous film micropores having communication properties there are many, are. 5 to 200 mu m thickness of the film, the average of both sides of the film pore size A ', both the A 2 0. 0 1 ⁇ 1 0 ⁇ , average porosity both sides of the film C ', also C 2 are both are at 48% or more, and an average pore size a of the one surface' average ratio of pore diameter a 2 of the other surface a '/ a 2 is from 0.3 to 3, the average porosity C of one surface' ratio C 'ZC 2 between the average porosity C 2 of the other surface is 0.7 to 1.5 A porous film is provided.
• the porous film of the present invention can be used for membrane separation techniques such as microfiltration and separation / concentration, and by filling the pores with a functional material, it can be used for battery separators, electrolytic capacitors, and circuits. It can be used as a wide range of substrate materials such as substrates.
• a polymer solution containing a polymer component as a material constituting a porous film is cast on a substrate in a film form, and a porous film is produced by a phase inversion method.
• polymer component examples include polymers such as amide imide polymers, imide polymers, amide polymers, sulfone polymers, cellulosic polymers, acryloline polymers, fluorine polymers, and olefin polymers.
• a solvent which is soluble in a water-soluble polar solvent and can form a film by a phase inversion method is used.
• the substrate examples include a glass plate; a polyolefin resin such as polyethylene, polypropylene, and polymethylpentene; nylon; and polyethylene terephthalate (PET).
• Plastic sheet consisting of polyester, polycarbonate, styrene resin, etc., fluorine resin such as PTFE (polytetrafluoroethylene), PVDF (polyvinylidene fluoride), vinyl chloride resin, other resin; stainless steel plate, aluminum plate, etc.
• Metal plate Note that a composite plate in which the surface material and the internal material are combined with different materials may be used.
• the difference is that a porous film is manufactured using a polymer and a substrate having a difference (S a -S b) of ⁇ 10 or more.
• the substrate is a composite plate in which the surface material and the internal material are different, it is only necessary that the surface tension of the material forming the contact surface with the polymer satisfies the above relationship.
• the (S a -S b) is less than -10, the polymer is agglomerated at the interface between the polymer and the substrate to form a dense phase. It becomes.
• a mixed solution containing the polymer causes a phase separation having a sea-island structure on the substrate, which is a source of micropores in the film. Therefore, it is possible to obtain a porous film having a high porosity particularly on the surface of the film that is in contact with the substrate (sometimes referred to as the “film substrate-side surface”).
• the polymer aggregated by the phase inversion method cannot wet the surface of the substrate and is repelled.
• more preferred Is 3 or more, more preferably 7 or more, and 13 or more is most preferable.
• the upper limit of the value of (S a — S b) is not particularly limited, and may be, for example, about 100.
• the polymer solution to be cast includes, for example, a polymer component 8 to 25% by weight, a water-soluble polymer 10 to 50% by weight, water 0 to 1 0% by weight, water-soluble polar solvent 30 to 82% by weight. /.
• a mixed solution consisting of At this time, if the concentration of the polymer component is too low, the strength of the film becomes weak, and if it is too high, the porosity becomes small.
• the water-soluble polymer is added to make the inside of the film a homogeneous sponge-like porous structure. If the concentration is too low, a large void exceeding 10 m will be generated inside the film, and the homogeneity will increase. Decreases. If the concentration of the water-soluble polymer is too high, the solubility is deteriorated. If the concentration is more than 50% by weight, problems such as a decrease in film strength are liable to occur.
• water-soluble polar solvent examples include dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide (DMAC), N-methyl-12-pyrrolidone (NMP), and 2-pyrrolidone And mixtures thereof.
• DMAC dimethyl sulfoxide
• N-dimethylformamide N, N-dimethylacetamide
• NMP N-methyl-12-pyrrolidone
• 2-pyrrolidone And mixtures thereof examples of the water-soluble polar solvent.
• Those having solubility according to the chemical skeleton of the polymer used as the polymer component can be used. These solvents can be used alone or in combination of two or more.
• the membrane structure in order to make the membrane structure porous in a sponge form, it is effective to add a water-soluble polymer or water to control the phase separation structure during casting.
• the water-soluble polymer include polyethylene glycol, polyvinyl pyrrolidone, polyethylene oxide, polyvinyl alcohol, polyacrylic acid, polysaccharides, and derivatives thereof. These water-soluble polymers can be used alone or in combination of two or more. Among these, polyvinyl pyrrolide is particularly preferred from the viewpoint of the communicability of the micropores present in the film.
• the molecular weight of the water-soluble polymer is preferably at least 100, more preferably at least 500, particularly preferably Is 10,000 or more (for example, about 10,000 to 200,000). The amount of water added can be used to adjust the diameter of the poison, and the diameter can be increased by increasing the amount of water added.
• the micropores can be formed uniformly.
• the film when the polymer solution is cast into a film, the film is placed in an atmosphere having a relative humidity of 70 to 100% and a temperature of 15 to 90 ° C. for 0.2 to 15 ° C. After holding for about one minute, it is desirable to lead to a coagulation liquid comprising a non-solvent of the polymer component. More preferred conditions are 90 to 100% relative humidity, 30 to 80 ° C, and particularly preferred conditions are about 100% relative humidity (for example, 95 to 100%). The temperature is between 40 and 70 ° C. If the amount of water in the air is lower than this, there is a problem that the opening ratio of the film becomes insufficient.
• the porosity of the surface opposite to the substrate side surface of the film (sometimes referred to as the “air side surface of the film”) can be particularly improved.
• the reason why the porosity is improved is considered to be that, by placing the film under humidification, moisture penetrates from the film surface to the inside, and the phase separation of the mixed solution is efficiently promoted.
• the coagulation solution used in the phase inversion method may be any solvent that coagulates the polymer component, and is appropriately selected depending on the type of the polymer used as the polymer component.
• water methanol
• Alcohols such as polyhydric alcohols such as polyhydric alcohols and glycerin
• water-soluble polymers such as polyethylene dalicol; mixtures thereof can be used.
• the production method of the present invention it is possible to obtain a porous film having a high porosity and in which uniform micropores are formed.
• the thickness of the porous film is, for example, 5 to 2 0 0 M m, preferably 1 0 ⁇ 1 0 0 ⁇ m, more preferably 2 0 to 8 0 m. If the thickness is too thin, the mechanical strength of the film becomes insufficient, while if it is too thick, it becomes difficult to control the pore size distribution uniformly.
• the porous portion is filled with a functional material, it is preferable that the porous material can be filled with a resolution of submicron to micron units.Therefore, the above-mentioned average pore size is preferable. On the other hand, if it is too large, it is difficult to control in submicron to micron units. Further, the maximum pore size on the film surface is preferably 15 ⁇ m or less.
• the average porosity (porosity) of a part of the porous film is, for example, 30 to 80%, preferably 40 to 80%, and more preferably 45 to 80%. If the porosity is too low, the permeation performance may not be sufficient, or the function may not be exhibited even if a functional material is filled. On the other hand, if the porosity is too high, the functional strength may be poor.
• the average porosity (surface porosity) on the surface of the film is, for example, 48% or more (for example, 48 to 80%), and preferably about 60 to 80%. If the surface porosity is too low, the permeation performance may not be sufficient, or even if a functional material is filled, the function may not be sufficiently exhibited. On the other hand, if the surface porosity is too high, the mechanical strength tends to decrease.
• the continuity of the micropores present in the film can be, for example, a Gurley value indicating air permeability, a pure water permeation rate, and the like as indexes.
• the Gurley value of the porous film is, for example, 0.2 to 29 seconds / 100 cc, preferably 1 to 25 seconds // 100 cc, particularly preferably 1 to 18 seconds 100 cc. It is. Larger numbers than this In some cases, the permeation performance in practical use is not sufficient, or the function cannot be exhibited because the functional material cannot be sufficiently filled. On the other hand, if the value is smaller than this, the mechanical strength may be poor. Further, pure water permeation rate is, for example 1. 3 X 1 0- 9 ⁇ : 1.
• a preferred porous film is a porous film having a large number of interconnected micropores, the thickness of the film is 5 to 200 ⁇ m, and the average pore diameter of the surface is 0.01 on both surfaces of the film. Up to 10 m, the ratio A / B of the average pore diameter A on the surface to the average pore diameter B on the inside is 0.3 to 3, and the ratio CZD of the average pore rate C on the surface to the average pore rate D on the inside is 0.7 to 1.5.
• the ratio C / D of the average pore size A of the surface to the average pore size B of the inside and the average pore size B of the inside, and the ratio C / D of the average pore ratio C of the surface to the inside average pore ratio D are preferably 0.5 to 2 for AZB.
• C / D is 0.75 to 1.4, more preferably A / B is 0.6 to 1.5, and CZD is 0.8 to 1.3. If these ratios are too small, the permeability may be poor or the functional material may not be sufficiently filled. If it is too large, there may be inconveniences such as poor separation characteristics and uneven filling of the functional material.
• porous film is a porous film having a large number of interconnected micropores, wherein the film has a thickness of 5 to 200 im, and The average pore diameters A 1 and A 2 on both sides are both 0.01 to 10 ⁇ , the average porosity C 1 and C 2 on both sides of the finolem are 48% or more, and one surface (for example, the substrate side surface) mean surface) pore size a 'and the other surface (for example, the average ratio eighth and pore size Alpha 2 air-side surface)' / eight 2 from 0.3 to 3, the average rate of hole area C 1 and the other of one surface ratio C'ZC 2 is 0.7 to 1 between the average porosity C 2 of the surface. 5.
• the ratio of the average pore size A of the one surface and the average porosity C 2 'and the other the average ratio of the hole diameter A 2 A surface' ⁇ 2, and an average rate of hole area C 1 and the other surface of the one surface C 'Zeta C is preferred properly the a' ⁇ 2 is a 0. 5 ⁇ 2 C 'ZC 2 is 0. 75 to 1 • 4, more preferably a' / Alpha 2 is 0.6 to 1. 5 and C′ZC 2 is 0.8 to 1.3. If these ratios are too small, the permeability may be poor or the functional material may not be sufficiently filled. On the other hand, if it is too large, there may be inconveniences such as poor separation characteristics and uneven filling of the functional material.
• the diameter, porosity, air permeability, and porosity of the micropores of the porous film are determined by the substrate used, the type and amount of the water-soluble polymer, the amount of water used, the humidity and temperature during casting, and It can be adjusted to a desired value by appropriately selecting time and time.
• a porous film having a characteristic that the ratio of the surface to the inside and the ratio of the substrate side surface to the air side surface are within the above ranges with respect to the average pore diameter and the average pore ratio. can be easily obtained.
• the measurement was carried out using a Gurley's Densometer manufactured by YOSHIMITSU in accordance with JISP 8117. However, since the measurement area was 1/10 of the standard device, it was converted to the standard galley value according to Appendix 1 of JISP 8117.
• the evaluation was performed using a flat membrane filter of Amicon STIRRED ULTRAFILTRATION CELLS MODELS 8200.
• the transmission area was 28.7 cm 2 .
• a filter paper was placed instead of a spacer on the transmission side to eliminate the resistance on the transmission side as much as possible.
• the pressure was measured at 0.5 kg / cm 2 and converted. Measurement temperature is 25 ° C Average surface pore size A
• the hole diameter was converted to the hole diameter assuming that the hole was a perfect circle, and the value was used as the average hole diameter.
• ⁇ represents the pi.
• the film was broken at liquid nitrogen temperature to expose the cross section of the film. If the film cannot be broken by this method, Was made to break at the temperature of liquid nitrogen while moistened with water to expose the cross section of the film.
• the obtained cross section of the film was used as a sample for an electron microscope, and the average pore diameter was determined by the same method as the above-described method for determining the average pore diameter on the surface. Maximum surface pore size
• Pore size 2 X (S max / ⁇ ) 1/2
• the film was broken at the temperature of liquid nitrogen to expose the cross section of the film.
• the film was broken at a temperature of liquid nitrogen in a state where the film was wetted with water in advance to expose the cross section of the film.
• the cross section of the obtained film was used as a sample for an electron microscope, and the maximum pore diameter was determined by the same method as the method for determining the maximum pore diameter on the surface described above. Average porosity of surface C
• the average open area of the surface was determined by selecting an arbitrary area of 20 ⁇ 20 Im from the electron micrograph of the film surface, and calculating the ratio of the total area of the holes existing therein to the entire area. This operation was performed for five arbitrary points, and the average value was obtained.
• the average pore size, maximum pore size, and average opening ratio in the above evaluation method were obtained only for the micropores visible in the foreground of the electron micrograph. Outside.
• the casting was performed in a 30 ° C., 80% RH atmosphere, and immediately after the casting, the container was kept in a container having a humidity of about 100% and a temperature of 45 ° C. for 4 minutes. Then, it was immersed in water for coagulation, and then dried to obtain a porous film. In this operation, the gap between the film preicker and the Teflon (registered trademark) substrate at the time of casting was 127 ⁇ , and the thickness of the obtained film was about 50 ⁇ m.
• pore size A 1 is about 0. 9 ⁇
• maximum pore diameter of 2 mean porosity at 5 m C 1 is approximately 6 5%
• an average pore pore diameter a 2 that exists in were not in contact with the substrate during cast film surface (air-side surface of the film) is about 1. 1 mu m
• the average rate of hole area at 7 mu m C 2 is about 70%
• Wataru the entire connexion average pore size B of about 1. 0 mu m, a maximum pore diameter of 1.
• the average open area ratio D inside the film was 70%.
• surface tension: 29 mN / m ( dyn / cm)
• pyrrolidone molecular weight: 360,000
• Added 15 parts by weight of NMP85 to 15 parts by weight A liquid B was prepared by adding 25 parts by weight of polybutylpyrrolidone (molecular weight: 50,000) to 100 parts by weight of the mixed solution obtained above.
• Teflon registered trademark
• the average pore size A ' is about 0. 3 ⁇ ⁇
• maximum pore diameter of average porosity C 1 at 0. 6 m pores which are present on the substrate side surface of the film is about 4 0%
• the average of the pores present on the air side surface of the film pore size a 2 is about 1. 0 mu m
• a maximum pore diameter of 2. 5 mu average porosity C 2 m is about 70%
• the film interior There were micropores that were nearly homogeneous and communicable with an average pore diameter B of about 1. ⁇ and a maximum pore diameter of 2. ⁇ over the entire area.
• the average open area ratio D inside the film was about 70%.
• the micropores present on the substrate side surface of the film were smaller than the micropores present on the air side surface and the inside of the film, had a low porosity, and lacked the homogeneity of the entire film. .
• Teflon registered trademark
• the average opening ratio C 1 was estimated to be 10% or less.
• the average pore diameter A 2 of the pores present on the air side surface of the film is about 1. 3 ⁇ ⁇ , maximum pore diameter of 2. 7 mu average porosity C 2 in ⁇ about 70%, the film inside is substantially homogeneous Micropores with an average pore size of about 1.2 Atm and a maximum pore size of 2.2 ⁇ m were present throughout the entire region. Also, The average porosity D inside the lum was about 70%.
• the substrate side surface of the film had a low porosity and a unique appearance as compared with the air side surface and the inside of the film, and lacked the uniformity of the film as a whole.
• the average pore size A 1 is about 1. 2 im, a maximum pore diameter of pores present on the substrate side surface of the film Ji 2. ( ⁇ average rate of hole area at !!! 1 1 0% or less, an average pore diameter a 2 of the pores present on the air side surface of the film is about 0. 8 m, a maximum pore diameter of 1. the average rate of hole area C 2 at 9 m to about 50%, the film interior Micropores with an average pore diameter B of about 2. ⁇ and a maximum pore diameter of 3.5 ⁇ were present throughout the entire area, and the average open area ratio D inside the film was about 70%.
• the surface of the film on the substrate side had a low porosity and lacked the uniformity of the film as a whole.
• Teflon registered trademark
• the average hole opening rate C ' was estimated to be 10% or less.
• the average pore diameter A 2 of the pores present on the air side surface of the film is about 0. 9 ⁇ ⁇ , maximum pore diameter of 2.
• the average rate of hole area C 2 in ⁇ ⁇ ⁇ about 50%, the film interior Wataru connexion the entire Micropores with continuity with an average pore size of about 2.2 ⁇ and a maximum pore size of 3.6 ⁇ m were present.
• the average porosity D inside the film was about 70%. From the above, the ratio to the air side surface and the inside of the film In comparison, the substrate side surface of the film had a low porosity and a unique appearance, and lacked the uniformity of the entire film.
• the porous film of the present invention can be used for membrane separation techniques such as microfiltration and separation / concentration, and by filling the pores with a functional material, battery separators, electrolytic capacitors, circuit boards, etc. Can be used as a wide range of substrate materials.

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• Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
• Separation Using Semi-Permeable Membranes (AREA)

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• 2003
  • 2003-08-19 EP EP20030811060 patent/EP1561561B1/en not_active Expired - Lifetime
  • 2003-08-19 CN CN038250969A patent/CN1694791B/zh not_active Expired - Fee Related
  • 2003-08-19 WO PCT/JP2003/010426 patent/WO2004043666A1/ja not_active Ceased
  • 2003-08-19 US US10/534,411 patent/US7820281B2/en not_active Expired - Fee Related
  • 2003-08-19 KR KR1020057008352A patent/KR100937077B1/ko not_active Expired - Fee Related
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