Patents by Inventor Yutaka Ohtsu

Yutaka Ohtsu 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: 7329386
    Abstract: The first subject of this invention is a column packing material comprising: a silica gel having a silanol group; a first chemical modification group which is bound to said silanol group; a silicone polymer for coating the surface of said silica gel; and, a trimethylsilyl group which is bound to the silanol group on said silicone polymer and/or the silanol group on said silica gel.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: February 12, 2008
    Assignee: Shiseido Co., Ltd.
    Inventors: Atsushi Kobayashi, Kazuko Takezawa, Hideki Takasaki, Taketoshi Kanda, Isao Tanaka, Tomoko Kimura, Yutaka Ohtsu
  • Publication number: 20040043493
    Abstract: The first subject of this invention is a column packing material comprising:
    Type: Application
    Filed: April 8, 2003
    Publication date: March 4, 2004
    Inventors: Atsushi Kobayashi, Kazuko Takezawa, Hideki Takasaki, Taketoshi Kanda, Isao Tanaka, Tomoko Kimura, Yutaka Ohtsu
  • Patent number: 6482867
    Abstract: There are disclosed a polymer packing material suitable for liquid chromatography and a producing method thereof. The polymer packing material having a polymer particle based on a styrene skeleton with monodispersed particle distribution can be obtained by hydrophilic treatment of an inner surface of a micropore existing in a fine pore of the polymer packing material, or subsequent introduction of a hydrophobic group into the inner hydrophilic surface by chemical modification. A method of producing the polymer packing material suitable for liquid chromatography includes the step of polymerizing glycerol dimethacrylate as a crosslinking agent and 2-ethylhexl methacrylate as a monomer according to a two-step swelling polymerization process. Alternatively, the producing method includes the step of crosslinking and polymerizing only glycerol dimethacrylate to form a polymer, and introducing the hydrophobic group into the polymer by chemical modification.
    Type: Grant
    Filed: August 20, 1999
    Date of Patent: November 19, 2002
    Assignee: Shiseido Co., Ltd.
    Inventors: Tomohiko Kimura, Masashi Teramachi, Ken Hosoya, Yutaka Ohtsu
  • Patent number: 6360589
    Abstract: A liquid chromatograph and a column packing material effectively condensing cationic specimen and exhibiting a high resolution. The liquid chromatograph includes a pre-focusing column (30, 40) having a volume of less than 2.0 milliliters and packed with a column packing material, in which a porous support is coated by a silicone polymer having a Si—R—X (R is a spacer part, X is a sulfonic group) bond and a Si—R′ (R′ is a hydrophilic group) bond, wherein the specimen to be analyzed is supplied to the pre-focusing column in the state dispersed in a solvent for condensation. The condensed specimen is then separated in a separation column (16, 43) used for separating the specimen dispersed in the solvent, and the separated specimen is analyzed by a detector (17, 41).
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: March 26, 2002
    Assignee: Shiseido Company, Ltd.
    Inventors: Taketoshi Kanda, Aya Ohkubo, Yutaka Ohtsu, Michihiro Yamaguchi
  • Patent number: 6316647
    Abstract: Disclosed herein are a cation-exchanged clay mineral comprising a swelling clay mineral with the cations between layers substantially replaced by low-valence metal amine complexes and/or low-valence metal ammine complexes, and a packing material for chromatography using the same. Use of the packing material provides a sharp peak with respect to a highly unsaturated compound. Since the packing material is unlikely to be influenced by a solvent, it is usable for a long time with good stability.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: November 13, 2001
    Assignee: Shiseido Company, Ltd.
    Inventors: Yutaka Ohtsu, Isao Tanaka, Yasuhiko Kadota, Michihiro Yamaguchi
  • Patent number: 6063283
    Abstract: A liquid chromatograph includes pumps for supplying solvents, a mixer for mixing the solvents, a controller for controlling a mixing ratio of the solvents in the mixer, a chromatograph column for separating a sample carried with the solvents, a flow path control valve for supplying the sample together with the solvents to the chromatograph column, and a detector for detecting the sample supplied thereto, wherein the mixer includes a mixing chamber and a porous medium accommodated in the mixing chamber, the porous medium having a size and shape in conformity with a size and shape of said mixing chamber such that no substantial gap is formed between an outer surface of the porous medium and an inner surface of the mixing chamber.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: May 16, 2000
    Assignee: Shiseido Company, Ltd.
    Inventors: Osamu Shirota, Ayako Suzuki, Yutaka Ohtsu, Michihiro Yamaguchi, Hisao Tsuruta
  • Patent number: 5990182
    Abstract: A method of producing a polymer packing material for liquid chromatography includes the steps of swelling seed polymer particles to form swelled particles, polymerizing monomers in the swelled particles under existence of diluent, and removing the diluent to form porous polymer particles, wherein the step of polymerizing the monomers is conducted under existence of a compound having a conjugated double bond not reactive with the monomers and having a molecular weight of 100-500. Alternatively, the polymerization process may be conducted by an oxidation reduction polymerization process. Further, the porous polymer particles obtained after removal of the diluent may be subjected to a heat treatment process at a temperature of 100.degree. C. or higher.
    Type: Grant
    Filed: September 15, 1998
    Date of Patent: November 23, 1999
    Assignee: Shiseido Company, Ltd.
    Inventors: Ken Hosoya, Yutaka Ohtsu, Osamu Shirota, Tomohiko Kimura
  • Patent number: 5738783
    Abstract: A liquid chromatograph includes pumps for supplying solvents, a mixer for mixing the solvents, a controller for controlling a mixing ratio of the solvents in the mixer, a chromatograph column for separating a sample carried with the solvents, a flow path control valve for supplying the sample together with the solvents to the chromatograph column, and a detector for detecting the sample supplied thereto, wherein the mixer includes a mixing chamber and a porous medium accommodated in the mixing chamber, the porous medium having a size and shape in conformity with a size and shape of said mixing chamber such that no substantial gap is formed between an outer surface of the porous medium and an inner surface of the mixing chamber.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: April 14, 1998
    Assignee: Shiseido Company, Ltd.
    Inventors: Osamu Shirota, Taketoshi Kanda, Ayako Suzuki, Yutaka Ohtsu, Michihiro Yamaguchi, Hisao Tsuruta, Ryujiro Namba
  • Patent number: 5672422
    Abstract: A packing material for a column comprises a porous support coated with silicone polymer having an Si--R bond, wherein R is a hydrophobic group and an Si--R' bond, wherein R' is a hydrophilic group, and a process for the production thereof.
    Type: Grant
    Filed: February 25, 1992
    Date of Patent: September 30, 1997
    Assignee: Shiseido Company Ltd.
    Inventors: Taketoshi Kanda, Atsuo Sakamoto, Michio Yokouchi, Yutaka Ohtsu
  • Patent number: 5318848
    Abstract: A packing material for a liquid chromatograph is provided particularly to be used for separating polycyclic aromatic compounds. The packing material is prepared by treating a base material of the packing material with a coupling agent of the formula (I): ##STR1## wherein Aro is an aromatic moiety, R.sup.1 and R.sup.2 are independently alkyl, alkenyl, aryl, lower alkoxy group, or halogen atom, R.sup.3 is a lower alkoxy group or halogen atom. Since an aromatic moiety within one molecule is immobilized through many functional groups on the surface of the base material, the packing material has stable and excellent separating properties.
    Type: Grant
    Filed: September 24, 1991
    Date of Patent: June 7, 1994
    Assignee: Shiseido Company Ltd.
    Inventors: Kenji Itoh, Hideo Nagashima, Kiyokatsu Jinno, Yutaka Ohtsu
  • Patent number: 5203991
    Abstract: A packing material for liquid chromatography bears a polyalkylene polyamine moiety linked through a spacer moiety as the pendant group to a porous silica gel coated with a silicone polymer, and optionally is crosslinked by a crosslinking agent on two or more amino group of the different polyalkylene polyamine moieties, and a process for production thereof. Such a packing material is especially useful in the analysis of sugars.
    Type: Grant
    Filed: October 17, 1991
    Date of Patent: April 20, 1993
    Assignee: Shiseido Company, Ltd.
    Inventors: Hiroshi Kutsuna, Yoshihiro Shiojima, Tsuneo Suhara, Hiroshi Fukui, Yutaka Ohtsu, Michihiro Yamaguchi
  • Patent number: 5145578
    Abstract: A packing material for liquid chromatography, comprising a spherical clay mineral powder which comprises a naturally occurring or synthetic water-swellable clay mineral, a clay mineral having foreign cations substantially substituted for interlayer ions inherently present in the naturally occurring or synthetic water-swellable clay mineral, or a calcined product thereof.
    Type: Grant
    Filed: September 24, 1990
    Date of Patent: September 8, 1992
    Assignee: Shiseido Company Ltd.
    Inventors: Kazo Tokubo, Michihiro Yamaguchi, Yutaka Ohtsu, Kiyoshi Nakamura, Satoshi Matsumoto, Akihiko Yamagishi
  • Patent number: 5135649
    Abstract: A column packing material comprising a porous support coated with a silicone polymer having an Si--R bond, wherein R is a hydrocarbon group having 1 to 18 carbon atoms, and an Si--R' bond, wherein R' is a hydrophilic group having one or more of polyoxyalkylene group or hydroxyl group at the terminal end, of which column packing material is produced by:modifying a porous support by bonding hydrocarbon groups to the porous support;eliminating a part of the hydrocarbon groups from the modified porous support; andmodifying the porous support by bonding hydrophilic groups thereto.
    Type: Grant
    Filed: September 25, 1990
    Date of Patent: August 4, 1992
    Assignee: Shiseido Company Ltd.
    Inventors: Taketoshi Kanda, Atsuo Sakamoto, Tadao Ohta, Yutaka Ohtsu
  • Patent number: 4882225
    Abstract: A modified powder or particulate material having a silicone polymer film coated on substantially the entire surface thereof, this powder or particulate material being produced by bringing at least one silicone compound, in the form of a vapor, having the general formula (I):(R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I)Wherein R.sup.1, R.sup.2, and R.sup.3 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, provided that R.sup.1, R.sup.2, and R.sup.3 are not hydrogen at the same time, R.sup.4, R.sup.5, and R.sup.
    Type: Grant
    Filed: April 26, 1988
    Date of Patent: November 21, 1989
    Assignee: Shiseido Company Ltd.
    Inventors: Hiroshi Fukui, Ryujiro Namba, Tsutomu Saito, Yutaka Ohtsu, Asa Kimura, Motokiyo Nakano, Okitsugu Nakata, Kenichi Tommita, Kazuo Tokubo, Kazuhisa Ohno, Toshio Yoneyama, Takashi Ogawa, Hideo Morohoshi, Junichi Koyama, Taketoshi Kanda, Kunihiro Kawaguchi, Yuzo Shimizu
  • Patent number: 4818614
    Abstract: A modified powder or particulate material coated on substantially the entire surface thereof with a film of a silicone polymer carrying a pendant group thereon, this powder or particulate material being produced by a process comprising the steps of(a) coating the powder or particulate material with a film of a silicone polymer having at least one Si-H moiety, and(b) carrying out an addition reaction of a compound capable of reacting with an Si--H moiety to the Si--H moiety in the silicone polymer of step (a), whereby the pendant group derived from said compound is bonded to the silicone polymer.
    Type: Grant
    Filed: July 25, 1986
    Date of Patent: April 4, 1989
    Assignee: Shiseido Company Ltd.
    Inventors: Hiroshi Fukui, Ryujiro Namba, Tsutomu Saito, Yutaka Ohtsu, Asa Kimura, Motokiyo Nakano, Okitsugu Nakata, Kenichi Tomita, Kazuo Tokubo, Kazuhisa Ohno, Toshio Yoneyama, Takashi Ogawa, Hideo Morohoshi, Junichi Koyama, Taketoshi Kanda, Kunihiro Kawaguchi, Yuzo Shimizu
  • Patent number: 4801445
    Abstract: A modified powder or particulate material having a silicone polymer film coated on substantially the entire surface thereof, this powder or particulate material being produced by bringing at least one silicone compound, in the form of a vapor, having the general formula (I):(R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I)wherein R.sup.1, R.sup.2, and R.sup.3 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, provided that R.sup.1, R.sup.2, and R.sup.3 are not hydrogen at the same time, R.sup.4, R.sup.5, and R.sup.
    Type: Grant
    Filed: June 17, 1986
    Date of Patent: January 31, 1989
    Assignee: Shiseido Company Ltd.
    Inventors: Hiroshi Fukui, Ryujiro Namba, Tsutomu Saito, Yutaka Ohtsu, Asa Kimura, Motokiyo Nakano, Okitsugu Nakata, Kenichi Tomita, Kazuo Tokubo, Kazuhisa Ohno, Toshio Yoneyama, Takashi Ogawa, Hideo Morohoshi, Junichi Koyama, Taketoshi Kanda, Kunihiro Kawaguchi, Yuzo Shimizu
  • Patent number: 4743377
    Abstract: A packing material for liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, the packing material being produced by a process comprising the steps of:(a) bringing at least one silicone compound having the general formula (I):(R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I)wherein R.sup.1, R.sup.2, and R.sup.3 represent, independently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R.sup.4, R.sup.5, and R.sup.
    Type: Grant
    Filed: June 30, 1986
    Date of Patent: May 10, 1988
    Assignee: Shiseido Company Ltd.
    Inventors: Yutaka Ohtsu, Hiroshi Fukui, Motokiyo Nakano, Okitsugu Nakata, Taketoshi Kanda, Isao Tanaka, Osamu Shirota, Junichi Koyama
  • Patent number: D288321
    Type: Grant
    Filed: June 5, 1984
    Date of Patent: February 17, 1987
    Assignee: Citizen Watch Co., Ltd.
    Inventor: Yutaka Ohtsu
  • Patent number: D290010
    Type: Grant
    Filed: October 2, 1984
    Date of Patent: May 26, 1987
    Assignee: Citizen Watch Co., Ltd.
    Inventor: Yutaka Ohtsu
  • Patent number: D297536
    Type: Grant
    Filed: June 9, 1985
    Date of Patent: September 6, 1988
    Assignee: Citizen Watch Co., Ltd.
    Inventor: Yutaka Ohtsu