Patents by Inventor Hideki Yokoyama
Hideki Yokoyama 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: 9102771Abstract: A method is disclosed for producing a water-absorbent resin by a reversed-phase suspension polymerization method, wherein an odor originating from a raw material component, in particular, a petroleum hydrocarbon dispersion medium, is further reduced as compared with a water-absorbent resin obtained by a conventional method, and a water-absorbent resin obtained by the method. More specifically, a method is disclosed for producing a water-absorbent resin by performing a reversed-phase suspension polymerization of a water-soluble ethylenically unsaturated monomer in a petroleum hydrocarbon dispersion medium, comprising adding and dispersing an aqueous solution of a water-soluble ethylenically unsaturated monomer containing a hydrophilic polymeric dispersion agent to a petroleum hydrocarbon dispersion medium in the presence of a surfactant under stirring, and performing a reversed-phase suspension polymerization using a radical polymerization initiator, and a water-absorbent resin obtained by the method.Type: GrantFiled: July 20, 2011Date of Patent: August 11, 2015Assignee: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Hideki Yokoyama, Atsushi Heguri, Nobuhiro Maeda
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Patent number: 9074022Abstract: A purpose of the present invention is to reduce odor of a water-absorbent resin during absorption of water. Such the invention is attained by a process for production of a water-absorbent resin by subjecting a water-soluble ethylenically unsaturated monomer to reversed-phase suspension polymerization. The process comprises the following steps (A) to (C): (A) adding an aqueous solution of water-soluble ethylenically unsaturated monomer to a petroleum hydrocarbon dispersion medium to disperse the aqueous solution in the dispersion medium; (B) adding a surfactant to the emulsion to further disperse the emulsion; and (C) performing the reversed-phase suspension polymerization using a water-soluble radical polymerization initiator, optionally in the presence of an internal-crosslinking agent.Type: GrantFiled: April 26, 2007Date of Patent: July 7, 2015Assignee: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Hideki Yokoyama, Yasuhiro Nawata
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Patent number: 8883944Abstract: A method for producing a water-absorbent resin by performing a reversed-phase suspension polymerization of a water-soluble ethylenically unsaturated monomer in a petroleum hydrocarbon dispersion medium, comprising the following steps of: (A) performing a primary dispersion in the absence of surfactants by adding an aqueous solution of a water-soluble ethylenically unsaturated monomer containing a hydrophilic polymeric dispersion agent to a petroleum hydrocarbon dispersion medium in which a hydrophobic polymeric dispersion agent was heat-dispersed or heat-dissolved, under stirring; (B) further performing a secondary dispersion by adding a surfactant to a dispersion liquid obtained after the primary dispersion; and (C) performing the reversed-phase suspension polymerization by using a radical polymerization initiator; and the water-absorbent resin obtained by the method.Type: GrantFiled: July 20, 2011Date of Patent: November 11, 2014Assignee: Sumitomo Seika Chemicals Co., Ltd.Inventors: Atsushi Heguri, Sachi Kikuno, Hideki Yokoyama, Nobuhiro Maeda
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Patent number: 8859700Abstract: A method for producing a water-absorbent resin having a further reduced odor as compared with a water-absorbent resin obtained by a conventional method as well as a water-absorbent resin produced by the same method, by maintaining the addition rate V from the pouring nozzle for the aqueous solution of the water-soluble ethylenically unsaturated monomer in a polymerization reaction tank not more than 0.30 [min?1], in the first stage polymerization step which is within the step of the conventional method upon performing multi-stages such as two or more stages of reversed-phase suspension polymerizations in a method for producing a water-absorbent resin, and thereby by being able to reduce the amount of the petroleum hydrocarbon dispersion medium remaining in the above water-absorbent resin.Type: GrantFiled: July 20, 2011Date of Patent: October 14, 2014Assignee: Sumitomo Seika Chemicals Co., Ltd.Inventors: Hideki Yokoyama, Sachi Kikuno, Atsushi Heguri, Nobuhiro Maeda
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Patent number: 8841395Abstract: The present invention provides a method for producing a water-absorbent resin by a reversed-phase suspension polymerization method, wherein an odor originating from a raw material component, in particular, a petroleum hydrocarbon dispersion medium, was reduced, and a water-absorbent resin obtained by the method. More specifically, the present invention provides a method for producing a water-absorbent resin comprising performing a reversed-phase suspension polymerization of a water-soluble ethylenically unsaturated monomer in a petroleum hydrocarbon dispersion medium by using a surfactant, wherein an aqueous solution of the water-soluble ethylenically unsaturated monomer is dispersed in the dispersion medium at a specific pouring rate to reduce an odor, and a water-absorbent resin obtained by the method, are provided.Type: GrantFiled: July 20, 2011Date of Patent: September 23, 2014Assignee: Sumitomo Seika Chemicals Co., Ltd.Inventors: Hideki Yokoyama, Sachi Kikuno, Atsushi Heguri, Nobuhiro Maeda
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Publication number: 20140179886Abstract: A method is disclosed for producing a water-absorbent resin by a reversed-phase suspension polymerization method, wherein an odor originating from a raw material component, in particular, a petroleum hydrocarbon dispersion medium, is further reduced as compared with a water-absorbent resin obtained by a conventional method, and a water-absorbent resin obtained by the method. More specifically, a method is disclosed for producing a water-absorbent resin by performing a reversed-phase suspension polymerization of a water-soluble ethylenically unsaturated monomer in a petroleum hydrocarbon dispersion medium, comprising adding and dispersing an aqueous solution of a water-soluble ethylenically unsaturated monomer containing a hydrophilic polymeric dispersion agent to a petroleum hydrocarbon dispersion medium in the presence of a surfactant under stirring, and performing a reversed-phase suspension polymerization using a radical polymerization initiator, and a water-absorbent resin obtained by the method.Type: ApplicationFiled: July 20, 2011Publication date: June 26, 2014Applicant: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Hideki Yokoyama, Atsushi Heguri, Nobuhiro Maeda
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Publication number: 20140094570Abstract: The present invention provides a water-absorbent resin produced by a reversed-phase suspension polymerization method, which contains a small amount of a petroleum hydrocarbon dispersion medium remaining therein used in reversed-phase suspension polymerization, and thus reducing an odor originating from the petroleum hydrocarbon dispersion medium, when the water-absorbent resin absorbs water, and also which is suitable for use in hygienic materials; an absorbent material and an absorbent article. More particularly, the present invention provides a water-absorbent resin obtained by subjecting an aqueous solution of a water-soluble ethylenically unsaturated monomer to reversed-phase suspension polymerization in a petroleum hydrocarbon dispersion medium in the presence of a surfactant, wherein the amount of the petroleum hydrocarbon dispersion medium remaining in the water-absorbent resin is 2,000 ppm or less; and an absorbent material and an absorbent article using the same.Type: ApplicationFiled: December 9, 2013Publication date: April 3, 2014Applicant: Sumitomo Seika Chemicals Co., Ltd.Inventors: Hideki Yokoyama, Yasuhiro Nawata
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Publication number: 20130123454Abstract: The present invention provides a method for producing a water-absorbent resin by a reversed-phase suspension polymerization method, wherein an odor originating from a raw material component, in particular, a petroleum hydrocarbon dispersion medium, was reduced, and a water-absorbent resin obtained by the method. More specifically, the present invention provides a method for producing a water-absorbent resin comprising performing a reversed-phase suspension polymerization of a water-soluble ethylenically unsaturated monomer in a petroleum hydrocarbon dispersion medium by using a surfactant, wherein an aqueous solution of the water-soluble ethylenically unsaturated monomer is dispersed in the dispersion medium at a specific pouring rate to reduce an odor, and a water-absorbent resin obtained by the method, are provided.Type: ApplicationFiled: July 20, 2011Publication date: May 16, 2013Applicant: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Hideki Yokoyama, Sachi Kikuno, Atsushi Heguri, Nobuhiro Maeda
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Publication number: 20130123455Abstract: A method for producing a water-absorbent resin having a further reduced odor as compared with a water-absorbent resin obtained by a conventional method as well as a water-absorbent resin produced by the same method, by maintaining the addition rate V from the pouring nozzle for the aqueous solution of the water-soluble ethylenically unsaturated monomer in a polymerization reaction tank not more than 0.30 [min?1], in the first stage polymerization step which is within the step of the conventional method upon performing multi-stages such as two or more stages of reversed-phase suspension polymerizations in a method for producing a water-absorbent resin, and thereby by being able to reduce the amount of the petroleum hydrocarbon dispersion medium remaining in the above water-absorbent resin.Type: ApplicationFiled: July 20, 2011Publication date: May 16, 2013Applicant: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Hideki Yokoyama, Sachi Kikuno, Atsushi Heguri, Nobuhiro Maeda
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Publication number: 20130119309Abstract: A method for producing a water-absorbent resin comprising at least two stages of reversed-phase suspension polymerization, wherein the first stage of the at least two stages of reversed-phase suspension polymerization comprises the following steps of: (A) performing a primary dispersion by stirring to mix in the absence of surfactants an aqueous solution of a water-soluble ethylenically unsaturated monomer containing a hydrophilic polymeric dispersion agent with a petroleum hydrocarbon dispersion medium in which a hydrophobic polymeric dispersion agent dissolves or disperses; (B) further performing a secondary dispersion by adding a surfactant to the resultant dispersion liquid; and (C) performing a polymerization by using a water-soluble radical polymerization initiator to obtain a water-absorbent resin as particles in a hydrous gel state which disperse in the petroleum hydrocarbon dispersion medium, and a water-absorbent resin obtained by the method.Type: ApplicationFiled: July 20, 2011Publication date: May 16, 2013Applicant: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Sachi Kikuno, Atsushi Heguri, Hideki Yokoyama, Nobuhiro Maeda
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Publication number: 20130123445Abstract: A method for producing a water-absorbent resin by performing a reversed-phase suspension polymerization of a water-soluble ethylenically unsaturated monomer in a petroleum hydrocarbon dispersion medium, comprising the following steps of: (A) performing a primary dispersion in the absence of surfactants by adding an aqueous solution of a water-soluble ethylenically unsaturated monomer containing a hydrophilic polymeric dispersion agent to a petroleum hydrocarbon dispersion medium in which a hydrophobic polymeric dispersion agent was heat-dispersed or heat-dissolved, under stirring; (B) further performing a secondary dispersion by adding a surfactant to a dispersion liquid obtained after the primary dispersion; and (C) performing the reversed-phase suspension polymerization by using a radical polymerization initiator; and the water-absorbent resin obtained by the method.Type: ApplicationFiled: July 20, 2011Publication date: May 16, 2013Applicant: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Atsushi Heguri, Sachi Kikuno, Hideki Yokoyama, Nobuhiro Maeda
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Publication number: 20100331802Abstract: The present invention provides a water-absorbent resin produced by a reversed-phase suspension polymerization method, which contains a small amount of a petroleum hydrocarbon dispersion medium remaining therein used in reversed-phase suspension polymerization, and thus reducing an odor originating from the petroleum hydrocarbon dispersion medium, when the water-absorbent resin absorbs water, and also which is suitable for use in hygienic materials; an absorbent material and an absorbent article. More particularly, the present invention provides a water-absorbent resin obtained by subjecting an aqueous solution of a water-soluble ethylenically unsaturated monomer to reversed-phase suspension polymerization in a petroleum hydrocarbon dispersion medium in the presence of a surfactant, wherein the amount of the petroleum hydrocarbon dispersion medium remaining in the water-absorbent resin is 2,000 ppm or less; and an absorbent material and an absorbent article using the same.Type: ApplicationFiled: August 14, 2008Publication date: December 30, 2010Applicant: SUMITOMO SEIKA CHEMICALS CO., LTD.Inventors: Hideki Yokoyama, Yasuhiro Nawata
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Publication number: 20100273647Abstract: A water-absorbent resin is provided which is suitable for absorbing polymer-containing viscous liquids, wherein the specific surface area measured by the BET multipoint technique using krypton gas as the adsorption gas is no less than 0.05 m2/g, and the water retention capacity for 0.9 wt % physiological saline is 5-30 g/g.Type: ApplicationFiled: July 8, 2010Publication date: October 28, 2010Applicant: Sumitomo Seika Chemicals Co., Ltd.Inventors: Yasuhiro NAWATA, Masakazu YAMAMORI, Koji UEDA, Hideki YOKOYAMA, Masato FUJIKAKE
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Publication number: 20090182092Abstract: A purpose of the present invention is to reduce odor of a water-absorbent resin during absorption of water. Such the invention is attained by a process for production of a water-absorbent resin by subjecting a water-soluble ethylenically unsaturated monomer to reversed-phase suspension polymerization. The process comprises the following steps (A) to (C): (A) adding an aqueous solution of water-soluble ethylenically unsaturated monomer to a petroleum hydrocarbon dispersion medium to disperse the aqueous solution in the dispersion medium; (B) adding a surfactant to the emulsion to further disperse the emulsion; and (C) performing the reversed-phase suspension polymerization using a water-soluble radical polymerization initiator, optionally in the presence of an internal-crosslinking agent.Type: ApplicationFiled: April 26, 2007Publication date: July 16, 2009Applicant: Sumitomo Seika Chemicals Co., Ltd.Inventors: Hideki Yokoyama, Yasuhiro Nawata
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Publication number: 20090136736Abstract: A water-absorbent resin is provided which is suitable for absorbing polymer-containing viscous liquids, wherein the specific surface area measured by the BET multipoint technique using krypton gas as the adsorption gas is no less than 0.05 m2/g, and the water retention capacity for 0.9 wt % physiological saline is 5-30 g/g.Type: ApplicationFiled: January 15, 2009Publication date: May 28, 2009Applicant: Sumitomo Seika Chemicals Co., Ltd.Inventors: YASUHIRO NAWATA, Masakazu Yamamori, Koji Ueda, Hideki Yokoyama, Masato Fujikake
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Patent number: 7318868Abstract: A ceramic capacitor having a ceramic body and terminal electrodes, the ceramic body being substantially a rectangular parallelopiped in shape, the terminal electrodes being provided at the two ends of the ceramic body in the length direction, each terminal electrode being provided to cover one end face of the ceramic body in the length direction, part of the two surfaces in the width direction, and part of the two surfaces in the thickness direction, wherein, when the length of the ceramic body is L1 and the maximum lengths of the terminal electrodes at the two surfaces of the ceramic body in the width direction are L3 and L4, 0?(|L4?L3|/L1)?0.0227 is satisfied. One surface among the two surfaces of the ceramic body in the width direction is the paste introduction side in the roller coating, while the other surface is the paste escape side in the roller coating.Type: GrantFiled: August 9, 2006Date of Patent: January 15, 2008Assignee: TDK CorporationInventors: Hideki Yokoyama, Atsushi Takeda
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Publication number: 20070178786Abstract: A water-absorbent resin is provided which is suitable for absorbing polymer-containing viscous liquids, wherein the specific surface area measured by the BET multipoint technique using krypton gas as the adsorption gas is no less than 0.05 m2/g, and the water retention capacity for 0.9 wt % physiological saline is 5-30 g/g.Type: ApplicationFiled: March 30, 2007Publication date: August 2, 2007Applicant: Sumitomo Seika Chemicals Co., Ltd.Inventors: Yasuhiro Nawata, Masakazu Yamamori, Koji Ueda, Hideki Yokoyama, Masato Fujikake
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Publication number: 20070000439Abstract: A ceramic capacitor having a ceramic body and terminal electrodes, the ceramic body being substantially a rectangular parallelopiped in shape, the terminal electrodes being provided at the two ends of the ceramic body in the length direction, each terminal electrode being provided to cover one end face of the ceramic body in the length direction, part of the two surfaces in the width direction, and part of the two surfaces in the thickness direction, wherein, when the length of the ceramic body is L1 and the maximum lengths of the terminal electrodes at the two surfaces of the ceramic body in the width direction are L3 and L4, 0?(|L4-L3|/L1)?0.0227 is satisfied. One surface among the two surfaces of the ceramic body in the width direction is the paste introduction side in the roller coating, while the other surface is the paste escape side in the roller coating.Type: ApplicationFiled: August 9, 2006Publication date: January 4, 2007Applicant: TDK CORPORATIONInventors: Hideki Yokoyama, Atsushi Takeda
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Patent number: 7115302Abstract: A ceramic capacitor having a ceramic body and terminal electrodes, the ceramic body being substantially a rectangular parallelopiped in shape, the terminal electrodes being provided at the two ends of the ceramic body in the length direction, each terminal electrode being provided to cover one end face of the ceramic body in the length direction, part of the two surfaces in the width direction, and part of the two surfaces in the thickness direction, wherein, when the length of the ceramic body is L1 and the maximum lengths of the terminal electrodes at the two surfaces of the ceramic body in the width direction are L3 and L4, 0?|(L4?L3|/L1?0.0227 is satisfied. One surface among the two surfaces of the ceramic body in the width direction is the paste introduction side in the roller coating, while the other surface is the paste escape side in the roller coating.Type: GrantFiled: May 18, 2004Date of Patent: October 3, 2006Assignee: TDK CorporationInventors: Hideki Yokoyama, Atsushi Takeda
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Patent number: 6991287Abstract: In a vehicle seat system equipped with an active headrest mechanism (30) and a lumbar support (21), a load-receiving part (32) of the active headrest mechanism (30) is positioned behind the lumbar support (21) as viewed from front of the seat. The vehicle seat system is arranged so that when a specified amount or more of load is applied from front of the seat to a lumbar support plate (22) of the lumbar support (21), one end part of a plate support member (23) supporting the lumbar support plate (22) exits from an insertion hole (17) provided at a side frame (4) to disengage from a seatback frame (2), and the disengaged end part of the plate support member (23) then abuts on the load-receiving part (32).Type: GrantFiled: June 2, 2005Date of Patent: January 31, 2006Assignees: Toyo Seat Co., Ltd., Mazda Motor CorporationInventors: Kazuharu Ogawa, Hideki Yokoyama, Kouji Matsushita, Kenji Muramatsu, Naoki Kaneko