Tokyo Ohka Kogyo Co., Ltd.

Tsukasa Sugawara

Mitsuharu Tobari

Takahiro Asai

Masanori Ichikawa

Jun Koshiyama

Kaoru Ishikawa

Yoshihiro Sawada

Yoshitsugu Kawamura

Akihiko Nakata

Akihito Morioka

Hayato Takashima

Takao Nakajima

To provide a method for producing a porous film in which even when minute fine particles are used, fine particles can be satisfactorily dispersed, a method for producing a composition for producing a porous film, and a porous film that can be produced by the method for producing a porous film. When a porous film is formed using a varnish including at least one resin component selected from the group consisting of polyamide acid, polyimide, a polyamide-imide precursor, polyamide-imide and polyethersulfone, and fine particles, varnish is produced by dispersing the fine particles by using a pressure device that pressurizes slurry including the fine particles and a dispersing device provided with a flow path whose cross-sectional area is 1960 &#x3bc;mor more and 785000 &#x3bc;mor less, and allowing the slurry pressurized to 50 MPa or more to pass through the flow path.

Method for producing porous film, method for producing composition for producing porous film, and porous film

Provided are a porous film having excellent surface smoothness and a method for producing the same. The surface roughness of a porous film of polyvinylidene fluoride, polyethersulfone, polyimide and/or polyamide-imide is Ra 30,000 &#x212b; or less. The opening diameter of the porous film is preferably from 100 nm to 5000 nm. The method for producing a porous film preferably includes a step for kneading a varnish containing fine particles and at least one resin selected from the group consisting of polyvinylidene fluoride, polyether sulfone, polyamic acid, polyimide, polyamide-imide precursor, and polyamide-imide. The varnish preferably has a viscosity at 25&#xb0; C. of 0.1-3 Pa&#xb7;s, a solids fraction concentration of 10-50 mass %, and a fine particle average particle size of 10-5000 nm.

Porous film and method for producing same

To provide a method for manufacturing a polyimide and/or a polyamide imide porous membrane with which it is possible to prepare a varnish in which microparticles are satisfactorily dispersed, even when minute microparticles are used, and to manufacture a porous membrane using the varnish. The method for manufacturing a polyimide and/or a polyamide imide porous membrane comprises a step for preparing a porous membrane manufacturing composition containing microparticles and at least one resin component selected from the group consisting of polyamic acids, polyimides, polyamide imide precursors, polyamide imides, and polyethersulfones, the preparation step including a dispersion step for causing a slurry containing the microparticles to disperse by shear and compression or shock.

Method for manufacturing porous membrane

A porous separator for secondary batteries is formed of a porous film, and has a first layered region having an average pore diameter of 100 nm or more and 500 nm or less, and a second layered region having a larger average pore diameter than the first layered region. The first layered region is positioned in one outermost surface of the porous film. Both the first layered region and the second layered region may be positioned as outermost surfaces of the porous film.

Porous separator for secondary batteries and secondary battery using same

The present invention addresses the problem of providing: a method for purifying a liquid using a porous polyimide and/or polyamideimide membrane having excellent impurities (e.g., metals) removal performance which is preferably compatible with a flow rate, and also having an excellent stress, an excellent breaking elongation and the like; a method for producing a chemical solution or a cleaning solution employing the purification method; a filter medium comprising the porous membrane; and a filter device equipped with the porous membrane. A method for purifying a liquid, comprising causing a portion or the whole of the liquid to pass through a porous polyimide and/or polyamideimide membrane having communicated pores from one side of the membrane to the other side of the membrane by the action of a differential pressure between the two sides.

Method for purifying liquid, method for producing chemical solution or cleaning solution, filter medium, and filter device

Provided are a polyimide and/or polyamideimide porous body and method for manufacturing same, method for separation and/or adsorption using the porous body, a separation material, adsorption material, and filter media composed of the porous body, a laminate, and a filter device. A polyimide and/or polyamideimide porous body in which the polyimide and/or polyamideimide has at least one group selected from the group consisting of a carboxy group, a salt-type carboxy group, and a &#x2014;NH&#x2014; bond.

Polyimide and/or polyamideimide porous body and method for manufacturing same, method for separation and/or adsorption, separation material, adsorption material, filter media, laminate, and filter device

To provide: a purification method which uses a polyimide and/or polyamide imide porous membrane that exhibits excellent removal performance for impurities such as metals, and wherein a liquid that is a silylating agent liquid, a film forming material or a diffusing agent composition is an object to be purified; a purification method for purifying a silicon compound-containing liquid that contains a silicon compound which is capable of producing a silanol group by hydrolysis; a method for producing a silylating agent liquid, a film forming material or a diffusing agent composition, which uses the purification method; a filter medium which is composed of the above-described porous membrane; and a filter device which comprises the above-described porous membrane. A purification method for purifying a liquid, which comprises a step in which some or all of the liquid is caused to permeate through a polyimide and/or polyamide imide porous membrane having communicating pores from one side to the other side by means of differential pressure, and wherein the liquid is a silylating agent liquid, a film forming material or a diffusing agent composition that is used for diffusing a dopant into a semiconductor substrate.

Purification method for purifying liquid, purification method for purifying silicon compound-containing liquid, method for producing silylating agent liquid, film forming material or diffusing agent composition, filter medium and filter device

A filtration filter used for filtering a liquid chemical for lithography, provided with a polyimide resin porous membrane; a filtration method including allowing a liquid chemical for lithography to pass through the filtration filter; and a production method of a purified liquid chemical product for lithography, including filtering a liquid chemical for lithography by the filtration method.

Filtration filter, filtration method, production method of purified liquid chemical product for lithography, and method of forming resist pattern

Provided are a varnish for porous polyimide film production, providing an unburned composite film that is less likely to have a sea-island structure, and a method for producing a porous polyimide film using the same. The varnish according to the present invention comprises a resin including polyamide acid and/or polyimide, fine particles, and a solvent, and has a fine particle content of not less than 65% by volume relative to the total of the resin and the fine particles and a viscosity at 25&#xb0; C. of not less than 550 mPa&#xb7;s. Preferably, the varnish further comprises a dispersant. The method for producing a porous polyimide film according to the present invention comprises: forming an unburned composite film using the varnish; burning the unburned composite film to obtain a polyimide-fine particle composite film; and removing the fine particles from the polyimide-fine particle composite film.

Varnish for porous polyimide film production and method for producing porous polyimide film using same

Provided is a method for producing a porous polyimide film with which it is possible to suppress the occurrence of curling in the polyimide-fine particle composite film obtained by firing the unfired composite film. The method for producing a porous polyimide film of the present invention includes, in the following order: forming an unfired composite film using a varnish that contains a resin including polyamide acid and/or polyimide, fine particles, and a solvent; immersing the unfired composite film in a solvent including water; firing the unfired composite film to obtain a polyimide-fine particle composite film; and removing the fine particles from the polyimide-fine particle composite film.

Method for producing porous polyimide film

A method for producing a porous polyimide film comprises: forming a first un-burned composite film wherein the first film is formed on a substrate using a first varnish that contains (A1) a polyamide acid or a polyimide and (B1) fine particles at a volume ratio (A1):(B1) of from 19:81 to 45:65; forming a second un-burned composite film wherein the second film is formed on the first film using a second varnish that contains (A2) a polyamide acid or a polyimide and (B2) fine particles at a volume ratio (A2):(B2) of from 20:80 to 50:50 and has a lower fine particle content ratio than the first varnish; burning wherein an un-burned composite film composed of the first film and the second film is burned, thereby obtaining a polyimide-fine particle composite film; and a fine particle removal step wherein the fine particles are removed from the polyimide-fine particle composite film.

Method for producing porous polyimide film, porous polyimide film and separator using same

A porous polyimide resin film having a high aperture ratio, and a method for producing a porous polyimide film. The method includes removing fine particles from a polyimide resin-fine particle composite film to obtain a porous polyimide resin film by either removing at least a part of a polyimide resin portion of the polyimide resin-fine particle composite film prior to removing the fine particles, or by removing at least a part of the porous polyimide resin film subsequent to removing the fine particles.

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Kanagawa, Japan

Tsukasa Sugawara