Patents by Inventor Tooru Kitagawa
Tooru Kitagawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 10814289Abstract: [Problem] To provide a membrane for the forward osmosis method, which keeps a high porosity, reduces concentration polarization by appropriately controlling the pore distribution, achieves both high water permeability and a self-supporting property, and has high chemical durability such that are membrane is applicable to various draw solutions. [Solution] A separation membrane having a structure inclined from an outer surface side to an inner surface side, a ratio between a thickness of a dense layer having a dense polymer density and a thickness of a coarse layer having a coarse polymer density being in a range of 0.25?(the thickness of the coarse layer)/[(the thickness of the dense layer)+(the thickness of the coarse layer)]?0.6, when measuring polymer density distribution in a thickness direction of the separation membrane by Raman spectroscopy.Type: GrantFiled: October 6, 2015Date of Patent: October 27, 2020Assignee: TOYOBO CO., LTD.Inventors: Takahito Nakao, Mayumi Akashi, Miyuki Yao, Seiji Watanuki, Tooru Kitagawa
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Publication number: 20170296985Abstract: [Problem] To provide a membrane for the forward osmosis method, which keeps a high porosity, reduces concentration polarization by appropriately controlling the pore distribution, achieves both high water permeability and a self-supporting property, and has high chemical durability such that the membrane is applicable to various draw solutions. [Solution] A separation membrane having a structure inclined from an outer surface side to an inner surface side, a ratio between a thickness of a dense layer having a dense polymer density and a thickness of a coarse layer having a coarse polymer density being in a range of 0.25?(the thickness of the coarse layer)/[(the thickness of the dense layer)+(the thickness of the coarse layer)]?0.6, when measuring polymer density distribution in a thickness direction of the separation membrane by Raman spectroscopy.Type: ApplicationFiled: October 6, 2015Publication date: October 19, 2017Applicant: TOYOBO CO., LTD.Inventors: Takahito Nakao, Mayumi Akashi, Miyuki Yao, Seiji Watanuki, Tooru Kitagawa
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Patent number: 9550153Abstract: The present invention provides a porous polymer flat-sheet membrane for MBR wherein surface of the porous polymer membrane is kept hydrophilic for a long period and high water permeability and anti-fouling properties are kept. A porous polymer flat-sheet membrane for MBR comprising a hydrophobic porous polymer membrane forming a network structure and a sheet substrate supporting it, characterized in that at least surface of the porous polymer membrane is coated and fixed with an insolubilized hydroxypropyl cellulose, that a ratio of the hydroxypropyl cellulose to the porous polymer membrane is 0.4 to 1.0% by weight and that, when NMR spectrum of the hydroxypropyl cellulose coated on and fixed to the membrane is measured using a nuclear magnetic resonance apparatus (proton NMR), an intensity ratio (B/A) of a spectral peak (B) appearing at 4.12 ppm to a spectral peak (A) appearing at 3.75 ppm is 12 to 30%.Type: GrantFiled: December 11, 2013Date of Patent: January 24, 2017Assignee: TOYOBO CO., LTD.Inventors: Junsuke Morita, Masao Higashi, Norifumi Shimada, Tooru Kitagawa
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Patent number: 9394638Abstract: A non-woven fabric which is excellent in thermal resistance, mechanical strength, and thermal dimensional stability for applications exposed to high temperature circumstance and has an extremely large surface area and exhibit an excellent filter performance is obtained. The non-woven fabric is composed of polyimide fibers which are obtained by polycondensation of at least an aromatic tetracarboxylic acid and an aromatic diamine having a benzoxazole structure and have a fiber diameter in the range of 0.001 ?m to 1 ?m. The non-woven fabric is obtained by the steps of preparing a polyamic acid by polycondensation of an aromatic tetracarboxylic acid and an aromatic diamine having a benzoxazole structure, and electro-spinning the polyamic acid to form a polyimide precursor non-woven fabric; and imidizing a polyimide precursor fiber bundle.Type: GrantFiled: June 19, 2007Date of Patent: July 19, 2016Assignee: Toyo Boseki Kabushiki KaishaInventors: Masahiko Nakamori, Satoshi Maeda, Tooru Kitagawa, Hisato Kobayashi, Yasuo Ohta
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Patent number: 9211509Abstract: To provide a reverse osmosis membrane where both salt rejection rate and water permeability required for wastewater treatment are achieved in a high level in spite of using the materials having excellent resistance to chemicals (resistance to alkali and to chlorine). A reverse osmosis membrane for wastewater treatment comprising a sulfonated poly(arylene ether sulfone) polymer containing a constituting component represented by the following formula [I], characterized in that, in a proton nuclear magnetic resonance spectrum where water molecules in the membrane are measured using the reverse osmosis membrane in a water-containing state, the relation between the chemical shift A (ppm) of spectral peak top derived from bound water and the chemical shift B (ppm) of spectral peak top derived from bulk water satisfies (B?0.36)?A<(B?0.30): wherein X is H or a univalent cationic species and n is an integer of 10 to 50.Type: GrantFiled: June 14, 2012Date of Patent: December 15, 2015Assignee: TOYOBO CO., LTD.Inventors: Masao Higashi, Junsuke Morita, Tooru Kitagawa
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Publication number: 20150328591Abstract: The present invention provides a porous polymer flat-sheet membrane for MBR wherein surface of the porous polymer membrane is kept hydrophilic for a long period and high water permeability and anti-fouling properties are kept. A porous polymer flat-sheet membrane for MBR comprising a hydrophobic porous polymer membrane forming a network structure and a sheet substrate supporting it, characterized in that at least surface of the porous polymer membrane is coated and fixed with an insolubilized hydroxypropyl cellulose, that a ratio of the hydroxypropyl cellulose to the porous polymer membrane is 0.4 to 1.0% by weight and that, when NMR spectrum of the hydroxypropyl cellulose coated on and fixed to the membrane is measured using a nuclear magnetic resonance apparatus (proton NMR), an intensity ratio (B/A) of a spectral peak (B) appearing at 4.12 ppm to a spectral peak (A) appearing at 3.75 ppm is 12 to 30%.Type: ApplicationFiled: December 11, 2013Publication date: November 19, 2015Applicant: TOYOBO CO., LTD.Inventors: Junsuke Morita, Masao Higashi, Norifumi Shimada, Tooru Kitagawa
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Publication number: 20150314245Abstract: The present invention provides a composite separation membrane having a separation layer formed of sulfonated polyarylene ether (SPAE) copolymer on a surface of a porous support membrane wherein both high separation property and high water permeation property are achieved. A composite separation membrane wherein a surface of a porous support membrane containing polyphenylene ether is coated with a thin film of a sulfonated polyarylene ether copolymer constituted from a repeating structure of a hydrophobic segment and a hydrophilic segment, characterized in that when proton nuclear magnetic resonance spectrum is measured at ?10° C., chemical shift of a spectral peak top derived from water contained in the membrane satisfies from 4.15 ppm to less than 5.00 ppm.Type: ApplicationFiled: December 11, 2013Publication date: November 5, 2015Applicant: TOYOBO CO., LTD.Inventors: Takahito Nakao, Takashi Ohkame, Ryouhei Yamane, Seiji Watanuki, Tooru Kitagawa
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Publication number: 20150136692Abstract: To provide a reverse osmosis membrane where both salt rejection rate and water permeability required for wastewater treatment are achieved in a high level in spite of using the materials having excellent resistance to chemicals (resistance to alkali and to chlorine). A reverse osmosis membrane for wastewater treatment comprising a sulfonated poly(arylene ether sulfone) polymer containing a constituting component represented by the following formula [I], characterized in that, in a proton nuclear magnetic resonance spectrum where water molecules in the membrane are measured using the reverse osmosis membrane in a water-containing state, the relation between the chemical shift A (ppm) of spectral peak top derived from bound water and the chemical shift B (ppm) of spectral peak top derived from bulk water satisfies (B?0.36)?A<(B?0.30): wherein X is H or a univalent cationic species and n is an integer of 10 to 50.Type: ApplicationFiled: June 14, 2012Publication date: May 21, 2015Applicant: TOYOBO CO., LTD.Inventors: Masao Higashi, Junsuke Morita, Tooru Kitagawa
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Patent number: 8580380Abstract: To provide fibers which retain the excellent heat resistance and flame retardancy inherent in polybenzazole fibers and pyridobisimidazole fibers, have improved post-processability and neither necessitate considerable change in production process conditions nor require a high-temperature and long-time heating treatment. With respect to the polybenzazole fiber and pyridobisimidazole fiber, in an electron diffraction diagram of a surface layer part (from the surface to 1 ?m) of the fibers, the fibers containing a crystal present in a state satisfying that S2/S1 is in a prescribed range, wherein S1 is a diffraction peak area derived from a crystal (200) plane and S2 is a diffraction peak area derived from a plurality of other crystal planes along an equatorial direction profile.Type: GrantFiled: August 22, 2007Date of Patent: November 12, 2013Assignee: Toyo Boseki Kabushiki KaishaInventors: Tooru Kitagawa, Kohei Kiriyama, Seiji Watanuki, Yoshihiko Teramoto, Yusuke Shimizu
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Process for producing polyester, polyester produced using said process, and polyester molded product
Patent number: 7868126Abstract: This invention provides a polyester and a polyester molded product, which, while maintaining color tone, transparency, and thermal stability, can realize a high polycondensation rate, are less likely to cause the production of polycondensation catalyst-derived undesired materials, and can simultaneously meet both quality and cost effectiveness requirements, which can exhibit the characteristic features, for example, in the fields of ultrafine fibers, high transparent films for optical use, or ultrahigh transparent molded products. These advantages can be realized by using, in the production of a polyester in the presence of an aluminum compound-containing polyester polycondensation catalyst, an aluminum compound having an absorbance of not more than 0.0132 as measured in the form of an aqueous aluminum compound solution, prepared by dissolving the aluminum compound in pure water to give a concentration of 2.Type: GrantFiled: June 24, 2005Date of Patent: January 11, 2011Assignee: Toyo Boseki Kabushiki KaishaInventors: Katsuhiko Kageyama, Tooru Kitagawa, Kenichi Funaki, Masaki Fuchikami, Kazuo Katayose, Takahiro Nakajima, Toshiyuki Tsuchiya, Satoru Nakagawa, Fumikazu Yoshida, Haruhiko Kohyama, Naoki Watanabe -
Patent number: 7811673Abstract: To provide a novel high strength polyethylene multifilament which consists of a plurality of filaments having high strengths and uniform internal structures, and showing a narrow variation in the strengths of the monofilaments, and which has been difficult to be provided by the conventional gel spinning method. A high strength polyethylene multifilament consisting of a plurality of filaments which are characterized in that the crystal size of monoclinic crystal is 9 nm or less; the stress Raman shift factor is ?5.0 cm?1/(cN/dTex) or more; the average strength is 20 CN/dTex or higher; the knot strength retention of each monofilament is 40% or higher; CV indicating a variation in the strengths of the monofilaments is 25% or lower; the elongation at break is from 2.5% inclusive to 6.0% inclusive; the fineness of each filament is 10 dTex or less; and the melting point of the filaments is 145° C. or higher.Type: GrantFiled: March 12, 2004Date of Patent: October 12, 2010Assignee: Toyo Boseki Kabushiki KaishaInventors: Godo Sakamoto, Tooru Kitagawa, Yasuo Ohta, Yasunori Fukushima, Hiroki Murase
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Publication number: 20100233451Abstract: To provide fibers which retain the excellent heat resistance and flame retardancy inherent in polybenzazole fibers and pyridobisimidazole fibers, have improved post-processability and neither necessitate considerable change in production process conditions nor require a high-temperature and long-time heating treatment. With respect to the polybenzazole fiber and pyridobisimidazole fiber, in an electron diffraction diagram of a surface layer part (from the surface to 1 ?m) of the fibers, the fibers containing a crystal present in a state satisfying that S2/S1 is in a prescribed range, wherein S1 is a diffraction peak area derived from a crystal (200) plane and S2 is a diffraction peak area derived from a plurality of other crystal planes along an equatorial direction profile.Type: ApplicationFiled: August 22, 2007Publication date: September 16, 2010Applicant: Toyo Boseki Kabushiki KaishaInventors: Tooru Kitagawa, Kohei Kiriyama, Seiji Watanuki, Yoshihiko Teramoto, Yusuke Shimizu
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Publication number: 20100178830Abstract: A non-woven fabric which is excellent in thermal resistance, mechanical strength, and thermal dimensional stability for applications exposed to high temperature circumstance and has an extremely large surface area and exhibit an excellent filter performance is obtained. The non-woven fabric is composed of polyimide fibers which are obtained by polycondensation of at least an aromatic tetracarboxylic acid and an aromatic diamine having a benzoxazole structure and have a fiber diameter in the range of 0.001 ?m to 1 ?m. The non-woven fabric is obtained by the steps of preparing a polyamic acid by polycondensation of an aromatic tetracarboxylic acid and an aromatic diamine having a benzoxazole structure, and electro-spinning the polyamic acid to form a polyimide precursor non-woven fabric; and imidizing a polyimide precursor fiber bundle.Type: ApplicationFiled: June 19, 2007Publication date: July 15, 2010Applicant: Toyo Boseki Kabushiki KaishaInventors: Masahiko Nakamori, Satoshi Maeda, Tooru Kitagawa, Hisato Kobayashi, Yasuo Ohta
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Patent number: 7649025Abstract: A composite ion exchange membrane having a high swelling resistance and being superior in mechanical strength and ion conductivity can be provided by means of an composite ion exchange membrane including an ion exchange resin composition and a support membrane having a continuous pore penetrating the support membrane, wherein the support membrane is one which accepts the ion exchange resin composition within the pore, and wherein the ion exchange resin composition is one which contains an ion exchange resin containing, as a main component, an aromatic polyether and/or its derivative, the aromatic polyether being obtained by mixing a compound having a specific structure, an aromatic dihalogenated compound and a bisphenol compound with a carbonate and/or a bicarbonate of an alkali metal and polymerizing the mixture in an organic solvent.Type: GrantFiled: October 16, 2003Date of Patent: January 19, 2010Assignee: Toyo Boseki Kabushiki KaishaInventors: Kota Kitamura, Yoshimitsu Sakaguchi, Shigenori Nagahara, Shiro Hamamoto, Naohiko Takimoto, Hideki Sugihara, Satoshi Takase, Tooru Kitagawa, Miyako Noshiro
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Process for Producing Polyester, Polyester Produced Using Said Process, and Polyester Molded Product
Publication number: 20080249280Abstract: This invention provides a polyester and a polyester molded product, which, while maintaining color tone, transparency, and thermal stability, can realize a high polycondensation rate, are less likely to cause the production of polycondensation catalyst-derived undesired materials, and can simultaneously meet both quality and cost effectiveness requirements, which can exhibit the characteristic features, for example, in the fields of ultrafine fibers, high transparent films for optical use, or ultrahigh transparent molded products. These advantages can be realized by using, in the production of a polyester in the presence of an aluminum compound-containing polyester polycondensation catalyst, an aluminum compound having an absorbance of not more than 0.0132 as measured in the form of an aqueous aluminum compound solution, prepared by dissolving the aluminum compound in pure water to give a concentration of 2.Type: ApplicationFiled: June 24, 2005Publication date: October 9, 2008Applicant: TOYO BOSEKI KABUSHIKI KAISHAInventors: Katsuhiko Kageyama, Tooru Kitagawa, Kenichi Funaki, Masaki Fuchikami, Kazuo Katayose, Takahiro Nakajima, Toshiyuki Tsuchiya, Satoru Nakagawa, Fumikazu Yoshida, Haruhiko Kohyama, Naoki Watanabe -
Publication number: 20070148452Abstract: PURPOSE: To provide a novel high strength polyethylene multifilament which consists of a plurality of filaments having high strengths and uniform internal structures, and showing a narrow variation in the strengths of the monofilaments, and which has been difficult to be provided by the conventional gel spinning method. SOLUTION: A high strength polyethylene multifilament consisting of a plurality of filaments which are characterized in that the crystal size of monoclinic crystal is 9 nm or less; the stress Raman shift factor is ?5.0 cm?1/(cN/dTex) or more; the average strength is 20 CN/dTex or higher; the knot strength retention of each monofilament is 40% or higher; CV indicating a variation in the strengths of the monofilaments is 25% or lower; the elongation at break is from 2.5% inclusive to 6.0% inclusive; the fineness of each filament is 10 dTex or less; and the melting point of the filaments is 145° C. or higher.Type: ApplicationFiled: March 12, 2004Publication date: June 28, 2007Inventors: Godo Sakamoto, Tooru Kitagawa, Yasuo Ohta, Yasunori Fukushima, Hiroki Murase
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Patent number: 7141301Abstract: A high strength polyethylene filament, wherein said filament has a fineness of 1.5 dtex or less as a monofilament, a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, the rate of dispersion-defective fibers cut from the filament is 2% or less, is disclosed, and a high strength polyethylene filament, wherein said filament has a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, a long period structure of 100 ? or less is observed in an X-ray small angle scattering pattern is disclosed.Type: GrantFiled: April 15, 2005Date of Patent: November 28, 2006Assignee: Toyo Boseki Kabushiki KaishaInventors: Godo Sakamoto, Tooru Kitagawa, Syoji Oda, Yasuo Ohta
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Publication number: 20060241192Abstract: A composite ion exchange membrane having a high swelling resistance and being superior in mechanical strength and ion conductivity can be provided by means of an composite ion exchange membrane including an ion exchange resin composition and a support membrane having a continuous pore penetrating the support membrane, wherein the support membrane is one which accepts the ion exchange resin composition within the pore, and wherein the ion exchange resin composition is one which contains an ion exchange resin containing, as a main component, an aromatic polyether and/or its derivative, the aromatic polyether being obtained by mixing a compound having a specific structure, an aromatic dihalogenated compound and a bisphenol compound with a carbonate and/or a bicarbonate of an alkali metal and polymerizing the mixture in an organic solvent.Type: ApplicationFiled: October 16, 2003Publication date: October 26, 2006Inventors: Kota Kitamura, Yoshimitsu Sakaguchi, Shigenori Nagahara, Shiro Hamamoto, Naohiko Takimoto, Hideki Sugihara, Satoshi Takase, Tooru Kitagawa, Miyako Noshiro
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Publication number: 20050238875Abstract: A high strength polyethylene filament, wherein said filament has a fineness of 1.5 dtex or less as a monofilament, a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, the rate of dispersion-defective fibers cut from the filament is 2% or less, is disclosed, and a high strength polyethylene filament, wherein said filament has a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, a long period structure of 100 ? or less is observed in an X-ray small angle scattering pattern is disclosed.Type: ApplicationFiled: April 15, 2005Publication date: October 27, 2005Applicant: Toyo Boseki Kabushiki KaishaInventors: Godo Sakamoto, Tooru Kitagawa, Syoji Oda, Yasuo Ohta
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Patent number: 6899950Abstract: A high strength polyethylene filament, wherein said filament has a fineness of 1.5 dtex or less as a monofilament, a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, the rate of dispersion-defective fibers cut from the filament is 2% or less, is disclosed, and a high strength polyethylene filament, wherein said filament has a tensile strength of 15 cN/dtex or more and a tensile elastic modulus of 300 cN/dtex or more, and, a long period structure of 100 ? or less is observed in an X-ray small angle scattering pattern is disclosed.Type: GrantFiled: December 7, 2001Date of Patent: May 31, 2005Assignee: Toyo Boseki Kabushiki KaishaInventors: Godo Sakamoto, Tooru Kitagawa, Syoji Oda, Yasuo Ohta