Patents by Inventor Taku Iwamura

Taku Iwamura 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).

  • Patent number: 10562006
    Abstract: The purpose of the present invention is to provide a particulate water absorbing agent having both a high water absorption multiplying factor and a high water absorption rate and a method for manufacturing the same. The present invention is a particulate water absorbing agent for which CRC is 30 to 50 g/g, wherein the weight average particulate diameter (D50) is 200-600 ?m, and the DRC index given by the following formula is a specific value (for example, 43, 30, or 20) or less: DRC index=(49?DRC5min [g/g])/(D50 [?m]/1000).
    Type: Grant
    Filed: March 28, 2017
    Date of Patent: February 18, 2020
    Assignee: NIPPON SHOKUBAI CO., LTD.
    Inventors: Kazushi Torii, Mariko Tamaki, Daisuke Takagi, Yuichiro Horimoto, Taishi Kobayashi, Taku Fujimoto, Takahiro Kitano, Taku Iwamura, Hiroki Kawada, Hiroyuki Goto, Yasuhisa Nakajima, Hiroyuki Ikeuchi
  • Publication number: 20200025714
    Abstract: Provided is a convenient, safe, and highly precise method for measuring a content of a water-absorbing resin in a hygienic material or an absorbent article.
    Type: Application
    Filed: September 29, 2017
    Publication date: January 23, 2020
    Applicant: Nippon Shokubai Co., Ltd.
    Inventors: Kazuki KIMURA, Taku IWAMURA, Takahiro KITANO, Hidenori WADA, Taku FUJIMOTO
  • Publication number: 20190338082
    Abstract: To provide a water-absorbing resin composition having both a high centrifuge retention capacity (CRC) and a sufficient urine resistance and a method for producing such a water-absorbing resin composition, an aspect of the present invention is a water-absorbing resin composition having the following properties: (1) A centrifuge retention capacity (CRC) being not less than 35 g/g; (2) A post-degradation-test one-hour eluted soluble component being not more than 19% by mass; (3) An absorbency against pressure 0.7 psi (AAP0.7) being not less than 10 g/g; and (4) A content of a water-absorbing resin in dust being not more than 300 ppm with respect to a total mass of the water-absorbing resin composition.
    Type: Application
    Filed: September 29, 2017
    Publication date: November 7, 2019
    Applicant: NIPPON SHOKUBAI CO., LTD.
    Inventors: Taku IWAMURA, Yasuhisa NAKAJIMA, Kazushi TORII, Taku FUJIMOTO, Hiroki KAWADA
  • Patent number: 10358558
    Abstract: A water-absorbent resin composition is provided which shows only small reduction in liquid permeability and limited coloring over time or in relation to another factor. The water-absorbent resin composition (particulate absorbent agent) of the present invention contains: a polycarboxylate-based water-absorbent resin as a primary component, the resin having a crosslinked structure formed by polymerization of an acid group-containing unsaturated monomer; and multivalent metal cations (preferably, on surfaces of particles (i.e., the water-absorbent resin composition)) wherein: the multivalent metal cations other than Fe cations account for 0.001 to 1 mass % of the water-absorbent resin; and the ratio of the Fe cations to the multivalent metal cations other than the Fe cations is less than or equal to 5.00 mass %.
    Type: Grant
    Filed: February 9, 2018
    Date of Patent: July 23, 2019
    Assignee: NIPPON SHOKUBAI CO., LTD.
    Inventors: Masatoshi Nakamura, Koji Miyake, Taku Iwamura, Yusuke Watanabe
  • Publication number: 20190111411
    Abstract: The purpose of the present invention is to provide a particulate water absorbing agent having both a high water absorption multiplying factor and a high water absorption rate and a method for manufacturing the same. The present invention is a particulate water absorbing agent for which CRC is 30 to 50 g/g, wherein the weight average particulate diameter (D50) is 200-600 ?m, and the DRC index given by the following formula is a specific value (for example, 43, 30, or 20) or less: DRC index=(49?DRC5min [g/g])/(D50 [?m]/1000).
    Type: Application
    Filed: March 28, 2017
    Publication date: April 18, 2019
    Inventors: Kazushi TORII, Mariko TAMAKI, Daisuke TAKAGI, Yuichiro HORIMOTO, Taishi KOBAYASHI, Taku FUJIMOTO, Takahiro KITANO, Taku IWAMURA, Hiroki KAWADA, Hiroyuki GOTO, Yasuhisa NAKAJIMA, Hiroyuki IKEUCHI
  • Publication number: 20180201788
    Abstract: A water-absorbent resin composition is provided which shows only small reduction in liquid permeability and limited coloring over time or in relation to another factor. The water-absorbent resin composition (particulate absorbent agent) of the present invention contains: a polycarboxylate-based water-absorbent resin as a primary component, the resin having a crosslinked structure formed by polymerization of an acid group-containing unsaturated monomer; and multivalent metal cations (preferably, on surfaces of particles (i.e., the water-absorbent resin composition)) wherein: the multivalent metal cations other than Fe cations account for 0.001 to 1 mass % of the water-absorbent resin; and the ratio of the Fe cations to the multivalent metal cations other than the Fe cations is less than or equal to 5.00 mass %.
    Type: Application
    Filed: February 9, 2018
    Publication date: July 19, 2018
    Inventors: Masatoshi NAKAMURA, Koji MIYAKE, Taku IWAMURA, Yusuke WATANABE
  • Patent number: 9926449
    Abstract: A water-absorbent resin composition is provided which shows only small reduction in liquid permeability and limited coloring over time or in relation to another factor. The water-absorbent resin composition (particulate absorbent agent) of the present invention contains: a polycarboxylate-based water-absorbent resin as a primary component, the resin having a crosslinked structure formed by polymerization of an acid group-containing unsaturated monomer; and multivalent metal cations (preferably, on surfaces of particles (i.e., the water-absorbent resin composition)) wherein: the multivalent metal cations other than Fe cations account for 0.001 to 1 mass % of the water-absorbent resin; and the ratio (in terms of percentage) of the Fe cations to the multivalent metal cations other than the Fe cations is less than or equal to 5.00 mass %.
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: March 27, 2018
    Assignee: NIPPON SHOKUBAI CO., LTD.
    Inventors: Masatoshi Nakamura, Koji Miyake, Taku Iwamura, Yusuke Watanabe
  • Patent number: 9775927
    Abstract: A particulate water absorbing agent of the present invention is a water absorbing agent containing a water absorbing resin as a main component, the particulate water absorbing agent containing a polyvalent metal cation and satisfying: (1) the polyvalent metal cation is contained in an amount between 0.001 wt % and 5 wt % relative to the amount of the water absorbing agent; (2) an absorbency without pressure (CRC) is not less than 28 (g/g) and an absorbency against pressure (AAP 4.83 kPa) is not less than 10 (g/g); (3) the absorbency against pressure and the absorbency without pressure satisfy 77 ?AAP (4.83 kPa)+1.8×CRC?100; and (4) a moisture content of the water absorbing agent is between 5 wt % and 20 wt %. This provides a water absorbing agent which has blocking resistance after moisture absorption, is excellent in stability to shock and suppresses Re-Wet when used in a diaper.
    Type: Grant
    Filed: December 8, 2014
    Date of Patent: October 3, 2017
    Assignee: NIPPON SHOKUBAI CO., LTD.
    Inventors: Taishi Kobayashi, Motohiro Imura, Taku Iwamura, Katsuyuki Wada, Kozo Nogi, Yoshiro Mitsukami, Masato Abe, Hiroko Ueda, Koji Honda
  • Publication number: 20150129799
    Abstract: A particulate water absorbing agent of the present invention is a water absorbing agent containing a water absorbing resin as a main component, the particulate water absorbing agent containing a polyvalent metal cation and satisfying: (1) the polyvalent metal cation is contained in an amount between 0.001 wt % and 5 wt % relative to the amount of the water absorbing agent; (2) an absorbency without pressure (CRC) is not less than 28 (g/g) and an absorbency against pressure (AAP 4.83 kPa) is not less than 10 (g/g); (3) the absorbency against pressure and the absorbency without pressure satisfy 77?AAP (4.83 kPa)+1.8×CRC?100; and (4) a moisture content of the water absorbing agent is between 5 wt % and 20 wt %. This provides a water absorbing agent which has blocking resistance after moisture absorption, is excellent in stability to shock and suppresses Re-Wet when used in a diaper.
    Type: Application
    Filed: December 8, 2014
    Publication date: May 14, 2015
    Inventors: Taishi KOBAYASHI, Motohiro IMURA, Taku IWAMURA, Katsuyuki WADA, Kozo NOGI, Yoshiro MITSUKAMI, Masato ABE, Hiroki UEDA, Koji HONDA
  • Patent number: 8975339
    Abstract: Provided is a surface treatment method for a water-absorbent resin having excellent production efficiency, absorption capacity against pressure, fluid permeability or the like. Provided is a method for the surface treatment of a water-absorbent resin which comprises a) a step for mixing 0.1 to 20 parts by weight of an acid group-containing radically polymerizable compound and 5 to 20 parts by weight of water, relative to 100 parts by weight of a water-absorbent resin; and b) a step for polymerizing the acid group-containing radically polymerizable compound, wherein neutralization ratio of the acid group-containing radically polymerizable compound is 0 to 60% by mol, and is lower than neutralization ratio of the water-absorbent resin.
    Type: Grant
    Filed: October 8, 2008
    Date of Patent: March 10, 2015
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Yoshiro Mitsukami, Taku Iwamura, Makoto Matsumoto
  • Patent number: 8952116
    Abstract: A particulate water absorbing agent of the present invention is a water absorbing agent containing a water absorbing resin as a main component, the particulate water absorbing agent containing a polyvalent metal cation and satisfying: (1) the polyvalent metal cation is contained in an amount between 0.001 wt % and 5 wt % relative to the amount of the water absorbing agent; (2) an absorbency without pressure (CRC) is not less than 28 (g/g) and an absorbency against pressure (AAP 4.83 kPa) is not less than 10 (g/g); (3) the absorbency against pressure and the absorbency without pressure satisfy 77?AAP (4.83 kPa)+1.8×CRC?100; and (4) a moisture content of the water absorbing agent is between 5 wt % and 20 wt %. This provides a water absorbing agent which has blocking resistance after moisture absorption, is excellent in stability to shock and suppresses Re-Wet when used in a diaper.
    Type: Grant
    Filed: September 29, 2010
    Date of Patent: February 10, 2015
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Taishi Kobayashi, Motohiro Imura, Taku Iwamura, Katsuyuki Wada, Kozo Nogi, Yoshiro Mitsukami, Masato Abe, Hiroko Ueda, Koji Honda
  • Patent number: 8735646
    Abstract: An absorbent article that has a thin, conformable absorbent core where the core has at least two layers, both of which are substantially free of cellulosic fibers is described. The first layer is intended to provide storage for the majority of acquired fluids and has an AAP of at least about 20 g/g and the second layer, which provides temporary capacity for the bulk of the acquired fluid and permanent storage for at least a portion thereof, comprises a second absorbent polymer material which has a Wet Permeability of at least about 400×10?7 (cm3 seconds)/g a ratio of Wet Permeability to SFC of at least about 1.5:1 with respect to the first absorbent polymer material.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: May 27, 2014
    Assignee: The Procter & Gamble Company
    Inventors: Holger Beruda, Yasue Nakagawa, Mattias Schmidt, Hiroyuki Ikeuchi, Kazushi Torii, Shigeru Sakamoto, Taku Iwamura, Sayaka Machida
  • Patent number: 8497226
    Abstract: An object of the present invention is to provide a water absorbent having excellent gel properties and showing excellent properties when used in a water-absorbing material of a sanitary/hygienic material such as paper diaper. Moreover, another object of the present invention is to provide a water absorbent which is safe and excellent in liquid permeability, and in which an amount of liquid permeability improver for improving the liquid permeability is reduced. The water absorbent is made from a water-absorbing resin prepared by a specific polymerization method and having a high degree of cross-linking, a high liquid holding property and a high gel strength (its swelling pressure of gel layer of is 35 kdyne/cm2 or more). This water absorbent is further processed to have a particular particle size distribution (95 wt % or more of its particles are less than 850ƒÊm but not less than 106ƒÊm, and logarithmic standard deviation (ƒĐƒÄ) is in a range of 0.25 to 0.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: July 30, 2013
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Kazushi Torii, Hirofumi Shibata, Taku Iwamura, Yoshio Irie, Yorimichi Dairoku, Yoshiro Mitsukami, Sayaka Machida
  • Patent number: 8247491
    Abstract: There are disclosed a water-absorbent resin composition and its production process, wherein the water-absorbent resin composition causes little gel-blocking and is excellent in the liquid permeability and liquid diffusibility and is high also in the absorption performances and further is strong also against the physical damage; and there are further disclosed a water-absorbent resin composition and its production process, wherein the water-absorbent resin composition has the following further advantages, in addition to the above, of involving little segregation of the metal compound and further having a dust prevention effect.
    Type: Grant
    Filed: February 6, 2004
    Date of Patent: August 21, 2012
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Kazushi Torii, Yoshiro Mitsukami, Motohiro Imura, Taku Iwamura, Toshimasa Kitayama, Kenji Kadonaga, Hiroki Inoue, Koji Miyake, Kozo Nogi, Masatoshi Nakamura, Shigeru Sakamoto, Sayaka Machida
  • Publication number: 20120184670
    Abstract: A particulate water absorbing agent of the present invention is a water absorbing agent containing a water absorbing resin as a main component, the particulate water absorbing agent containing a polyvalent metal cation and satisfying: (1) the polyvalent metal cation is contained in an amount between 0.001 wt % and 5 wt % relative to the amount of the water absorbing agent; (2) an absorbency without pressure (CRC) is not less than 28 (g/g) and an absorbency against pressure (AAP 4.83 kPa) is not less than 10 (g/g); (3) the absorbency against pressure and the absorbency without pressure satisfy 77?AAP (4.83 kPa)+1.8×CRC?100; and (4) a moisture content of the water absorbing agent is between 5 wt % and 20 wt %. This provides a water absorbing agent which has blocking resistance after moisture absorption, is excellent in stability to shock and suppresses Re-Wet when used in a diaper.
    Type: Application
    Filed: September 29, 2010
    Publication date: July 19, 2012
    Applicant: Nippon Shokubai Co., Ltd.
    Inventors: Taishi Kobayashi, Motohiro Imura, Taku Iwamura, Katsuyuki Wada, Kozo Nogi, Yoshiro Mitsukami, Masato Abe, Hiroko Ueda, Koji Honda
  • Patent number: 7981833
    Abstract: An object of the present invention is to provide an aqueous-liquid-absorbing agent which comprises water-absorbent resin particles as essential components and is suitable for uses in sanitary materials. As a means of achieving this object, an aqueous-liquid-absorbing agent according to the present invention is an aqueous-liquid-absorbing agent comprising water-absorbent resin particles as essential components, wherein the water-absorbent resin particles are obtained by a process including the step of polymerizing a water-soluble ethylenically unsaturated monomer and have a crosslinked structure in their inside; with the aqueous-liquid-absorbing agent exhibiting an absorption rate (FSR) of not less than 0.2 g/g/s, a water absorption capacity (CRC) of 5 to 25 g/g, a saline flow conductivity (SFC) of not less than 400×10?7 cm3·s/g, and a wet porosity of not less than 20%.
    Type: Grant
    Filed: March 11, 2005
    Date of Patent: July 19, 2011
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Hiroyuki Ikeuchi, Kazushi Torii, Shigeru Sakamoto, Taku Iwamura, Sayaka Machida
  • Patent number: 7960469
    Abstract: The production method of a water absorbent resin composition including a particulate water absorbent resin, wherein: 95 wt % or more of particles whose particle diameter is less than 850 ?m and not less, than 106 ?m are contained, and a weight average particle diameter of the particles is less than 500 ?m and not less than 300 ?m and a logarithmic standard deviation (??) of a particle size distribution is 0.45 or less, and a water-soluble component of the water absorbent composition is 35 wt % or less, and a multivalent metal component is contained, and an extraction rate of the multivalent metal component is 5.0 wt % or more and less than 100 wt %, thereby providing the water absorbent resin composition, free from any coagulation of particles in high humidity, which has superior absorbent property in terms of an absorbency and a diffusing absorbency under pressure.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: June 14, 2011
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Yoshifumi Adachi, Takahiro Kitano, Shinichi Fujino, Katsuyuki Wada, Kazushi Torii, Taku Iwamura, Sayaka Machida
  • Patent number: 7879923
    Abstract: This invention is to provide a method for surface-treatment of a water absorbent resin excelling in water absorption properties. This invention relates to a method for the surface-treatment of a water absorbent resin, which comprises: a) mixing 100 parts by weight of a water absorbent resin, 0.01-20 parts by weight of at least one radical polymerization initiator selected from the group consisting of persulfates, hydrogen peroxide, and azo compounds, and a radically polymerizing compound and b) irradiating the resultant mixture with active energy rays. The treatment particularly exalts the absorption ratio against pressure and the saline flow conductivity.
    Type: Grant
    Filed: December 9, 2005
    Date of Patent: February 1, 2011
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Makoto Matsumoto, Yoshiro Mitsukami, Hiroyuki Ikeuchi, Kazushi Torii, Taku Iwamura
  • Patent number: 7875362
    Abstract: An absorbent member and a method for making such an absorbent member. The absorbent member includes a modified water absorbent resin having good production efficiency, absorbency against pressure, absorption speed, gel strength, and liquid permeability. The modified water absorbent resin may be made by mixing a water absorbent resin, water, and a water-soluble radical polymerization initiator without addition of an ethylenically unsaturated monomer to obtain a water absorbent resin composition, and irradiating the water absorbent resin composition with active energy rays. During irradiation, the surface water content of the water absorbent resin is at least 3.0 wt %.
    Type: Grant
    Filed: May 20, 2010
    Date of Patent: January 25, 2011
    Assignee: The Procter & Gamble Company
    Inventors: Yoshiro Mitsukami, Makoto Matsumoto, Taku Iwamura
  • Patent number: 7872076
    Abstract: An object of the present invention is to provide a particulate water-absorbent resin composition and its production process, wherein the particulate water-absorbent resin composition is an enhanced one in both of the “liquid permeability” and “liquid-sucking-up property” (which have hitherto been antithetical physical properties) of the water-absorbent resin. As a means of achieving this object, a first particulate water-absorbent resin composition according to the present invention is a particulate water-absorbent resin composition comprising a water-absorbent resin (A) of a crosslinked structure obtained by polymerizing an acid-group-containing unsaturated monomer, with the composition being characterized by: having a particle size such that particles in the range of 850 to 150 ?m (but not including 850 ?m) account for not less than 90 weight % of the entirety; and containing a tetra- or more functional polyol (B) at least on surfaces.
    Type: Grant
    Filed: November 5, 2004
    Date of Patent: January 18, 2011
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Hiroyuki Ikeuchi, Kazushi Torii, Taku Iwamura, Sayaka Machida, Hiroko Okochi