Patents by Inventor Takeshi Ichitsuka

Takeshi Ichitsuka 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: 6306297
    Abstract: Column packing materials useful in applications such as liquid chromatography, as well as a process for producing such a packing material are described. A first aspect of the invention concerns a column packing material composed of a spherical substrate having a coating of a calcium phosphate based compound on the surface thereof. A second aspect of the invention concerns a packing material comprising porous calcium phosphate based granules having open pores with an average pore size of from 0.01 to 20 &mgr;m, said granules being composed of crystalline particles with an average size of from 0.1 to 10 &mgr;m. A third aspect of the invention concerns a spherical packing material for liquid chromatography comprising spherical particles of at least one material selected from the group consisting of Ca10(PO4)6(OH)2, Ca3(PO4)2, Ca2P2O7, Ca(PO3)2, Ca10(PO4)6F2 and Ca10(PO4)6Cl2, said packing material having a dense structure with a porosity of no more than 5%.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: October 23, 2001
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Masaya Sumita, Akihiko Yokoo, Katsumi Kawamura
  • Patent number: 5651884
    Abstract: Column packing materials useful in applications such as liquid chromatography, as well as a process for producing such a packing material are described. A first aspect of the invention concerns a column packing material composed of a spherical substrate having a coating of a calcium phosphate based compound on the surface thereof.A second aspect of the invention concerns a packing material comprising porous calcium phosphate based granules having open pores with an average pore size of from 0.01 to 20 .mu.m, said granules being composed of crystalline particles with an average size of from 0.1 to 10 .mu.m.A third aspect of the invention concerns a spherical packing material for liquid chromatography comprising spherical particles of at least one material selected from the group consisting of Ca.sub.10 (PO.sub.4).sub.6 (OH).sub.2, Ca.sub.3 (PO.sub.4).sub.2, Ca.sub.2 P.sub.2 O.sub.7, Ca(PO.sub.3).sub.2, Ca.sub.10 (PO.sub.4).sub.6 F.sub.2 and Ca.sub.10 (PO.sub.4).sub.6 Cl.sub.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: July 29, 1997
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Katsumi Kawamura, Masaya Sumita, Akihiko Yokoo
  • Patent number: 5651882
    Abstract: Column packing materials useful in applications such as liquid chromatography, as well as a process for producing such a packing material are described. A first aspect of the invention concerns a column packing material composed of a spherical substrate having a coating of a calcium phosphate based compound on the surface thereof.A second aspect of the invention concerns a packing material comprising porous calcium phosphate based granules having open pores with an average pore size of from 0.01 to 20 .mu.m, said granules being composed of crystalline particles with an average size of from 0.1 to 10 .mu.m.A third aspect of the invention concerns a spherical packing material for liquid chromatography comprising spherical particles of at least one material selected from the group consisting of Ca.sub.10 (PO.sub.4).sub.6 (OH).sub.2, Ca.sub.3 (PO.sub.4).sub.2, Ca.sub.2 P.sub.2 O.sub.7, Ca(PO.sub.3).sub.2, Ca.sub.10 (PO.sub.4).sub.6 F.sub.2 and Ca.sub.10 (PO.sub.4).sub.6 Cl.sub.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: July 29, 1997
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Katsumi Kawamura, Akihiko Yokoo
  • Patent number: 5441635
    Abstract: Column packing materials useful in applications such as liquid chromatography, as well as a process for producing such a packing material are described. A first aspect of the invention concerns a column packing material composed of a spherical substrate having a coating of a calcium phosphate based compound on the surface thereof.A second aspect of the invention concerns a packing material comprising porous calcium phosphate based granules having open pores with an average pore size of from 0.01 to 20 .mu.m, said granules being composed of crystalline particles with an average size of from 0.1 to 10 .mu.m.A third aspect of the invention concerns a spherical packing material for liquid chromatography comprising spherical particles of at least one material selected from the group consisting of Ca.sub.10 (PO.sub.4).sub.6 (OH).sub.2, Ca.sub.3 (PO.sub.4).sub.2, Ca.sub.2 P.sub.2 O.sub.7, Ca(PO.sub.3).sub.2, Ca.sub.10 (PO.sub.4).sub.6 F.sub.2 and Ca.sub.10 (PO.sub.4).sub.6 Cl.sub.
    Type: Grant
    Filed: March 10, 1993
    Date of Patent: August 15, 1995
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Masaya Sumita
  • Patent number: 5240659
    Abstract: An oriented shaped article of a calcium phosphate type compound is disclosed, in which at least two crystallographic axes of the primary particles of which the shaped article is composed each is oriented in one direction, respectively, in at least the surface of said article. A sinter of the oriented shaped article and a processes for producing the article and the sinter are also disclosed.
    Type: Grant
    Filed: March 24, 1992
    Date of Patent: August 31, 1993
    Assignee: Asahi Kogaku K.K.
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Masaya Sumita, Akihiko Yokoo
  • Patent number: 5134009
    Abstract: An oriented shaped article of a calcium phosphate type compound is disclosed, in which at least two crystallographic axes of the primary particles of which the shaped article is composed each is oriented in one direction, respectively, in at least the surface of said article. A sinter of the oriented shaped article and a processes for producing the article and the sinter are also disclosed.
    Type: Grant
    Filed: September 14, 1989
    Date of Patent: July 28, 1992
    Assignee: Asahi Kogaku Kogyo K.K.
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Masaya Sumita, Akihiko Yokoo
  • Patent number: 5089195
    Abstract: A method for producing a calcium phosphate-based material comprising:(a) molding a calcium phosphate powder;(b) preliminarily calcining the resulting molding in a vacuum or under a reduced pressure until the relative density is 95% or more; and(c) firing the molding in air, an inert gas, or nitrogen gas.
    Type: Grant
    Filed: June 22, 1990
    Date of Patent: February 18, 1992
    Assignee: Asahi Kogaku Kogyo K.K.
    Inventors: Takeshi Ichitsuka, Yasuhiko Hirayama, Tetsuro Ogawa
  • Patent number: 5085781
    Abstract: A separating agent which includes a polyvinyl acetal resin having open cell structure and an average pore size of from about 10 to about 1000 micrometers; and, porous calcium phosphate granules having open cell structure, and also having two distributions of pore size wherein one distribution has micropores ranging from about 20 to about 500 nm in average pore size and the other distribution has small pores ranging from about 1 to about 50 micrometers in average pore size. Alternatively, the separating agent includes a polyvinyl acetal resin having open cell structure and having an average pore size of from about 10 to about 1000 micrometers as a first element, and a layer of porous calcium phosphate granules having an average granule size of from about 10 to about 2000 micrometers as a second element applied onto the first element. The separating agents may be used in a separator, and may be employed in separating methods.
    Type: Grant
    Filed: February 28, 1990
    Date of Patent: February 4, 1992
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Sumiaki Tsuru, Akihiko Yokoo, Takeshi Ichitsuka, Tsuneo Hiraide
  • Patent number: 5064436
    Abstract: A bone prosthetic material composed of calcium phosphate group granules which have open cells with an average pore size of 0.01-(10 .mu.m).sup.2 over a surface density of at least one per 10 .mu.m.sup.2. The prosthetic material is prepared by mixing organic inflammable particles with a calcium based powder, granulating and then firing the mixture.
    Type: Grant
    Filed: July 3, 1989
    Date of Patent: November 12, 1991
    Assignee: Asahi Kogaku Kogyo K.K.
    Inventors: Makoto Ogiso, Tetsuro Ogawa, Takeshi Ichitsuka, Masahide Inoue
  • Patent number: 5055307
    Abstract: Slow release drug delviery granules comprising porous granules of a calcium phosphate compound having an atomic ratio of Ca to P of 1.3 to 1.8, a porosity of 0.1 to 70%, a specific surface area of 0.1 to 50 m.sup.2 /g and a pore size of 1 nm to 10 .mu.m, fired at a temperature of 200.degree. to 1400.degree. C., and a drug component impregnated in pores of the granules, and a process for producing the same. The drug delivery granules of the present invention have a controllable, prolonged effect of drug release and a good imaging property to an X-ray or ultrasonic wave, and therefore can be advantageously utilized in the field of chemotherapy.
    Type: Grant
    Filed: December 28, 1989
    Date of Patent: October 8, 1991
    Assignee: Asahi Kagaku Kogyo Kabushiki Kaisha
    Inventors: Sumiaki Tsuru, Masashi Tsugita, Ken Takasaki, Akihiko Yokoo, Takeshi Ichitsuka
  • Patent number: 5039408
    Abstract: Column packing materials useful in applications such as liquid chromatography, as well as a process for producing such a packing material are described. A first aspect of the invention concerns a column packing material composed of a spherical substrate having a coating of a calcium phosphate based compound on the surface thereof.A second aspect of the invention concerns a packing material comprising porous calcium phosphate based granules having open pores with an average pore size of from 0.01 to 20 .mu.m, said granules being composed of crystalline particles with an average size of from 0.1 to 10 .mu.m.A third aspect of the invention concerns a spherical packing material for liquid chromatography comprising spherical particles of at least one material selected from the group consisting of Ca.sub.10 (PO.sub.4).sub.6 (OH).sub.2, Ca.sub.3 (PO.sub.4).sub.2, Ca.sub.2 P.sub.2 O.sub.7, Ca(PO.sub.3).sub.2, Ca.sub.10 (PO.sub.4).sub.6 F.sub.2 and Ca.sub.10 (PO.sub.4).sub.6 Cl.sub.
    Type: Grant
    Filed: January 8, 1990
    Date of Patent: August 13, 1991
    Assignee: Asahi Kogaku Kogyo K.K.
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Masaya Sumita, Akihiko Yokoo, Katsumi Kawamura
  • Patent number: 4957674
    Abstract: A method for producing a calcium phosphate-based material comprising:(a) molding a calcium phosphate powder;(b) preliminarily calcining the resulting molding in a vacuum or under a reduced pressure until the relative density is 95% or more; and(c) firing the molding in air, an inert gas, or nitrogen gas.
    Type: Grant
    Filed: May 11, 1988
    Date of Patent: September 18, 1990
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Takeshi Ichitsuka, Yasuhiko Hirayama, Tetsuro Ogawa
  • Patent number: 4798585
    Abstract: A support for a biomedical implant device in which the support has a surface layer composed of a biocompatible calcium phosphate material such as sintered hydroxyapatite with a porosity of 50-60% and pore size of 0.5-500 micrometers. Preferably, the surface layer is formed with projections or recesses of a few hundred micrometers size.
    Type: Grant
    Filed: June 8, 1987
    Date of Patent: January 17, 1989
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Masahide Inoue, Takeshi Ichitsuka, Yasuhiko Hirayama, Shozo Koshikawa, Tateki Kitaoka, Nobuo Nakabayashi, Tatsumichi Takeda, Osamu Minoo
  • Patent number: RE34037
    Abstract: A support for a biomedical implant device in which the support has a surface layer composed of a biocompatible calcium phosphate material such as sintered hydroxyapatite with a porosity of 50-60% and pore size of 0.5-500 micrometers. Preferably, the surface layer is formed with projections or recesses of a few hundred micrometers size.
    Type: Grant
    Filed: January 17, 1991
    Date of Patent: August 18, 1992
    Assignee: Asahi Kogaku Kogyo K.K.
    Inventors: Masahide Inoue, Takeshi Ichitsuka, Yasuhiko Hirayama, Shozo Koshikawa, Tateki Kitaoka, Nobuo Nakabayashi, Tatsumichi Takeda, Osamu Minoo
  • Patent number: RE35267
    Abstract: A separating agent which includes a polyvinyl acetal resin having open cell structure and an average pore size of from about 10 to about 1000 micrometers; and, porous calcium phosphate granules having open cell structure, and also having two distributions of pore size wherein one distribution has micropores ranging from about 20 to about 500 mm in average pore size and the other distribution has small pores ranging from about 1 to about 50 micrometers in average pore size. Alternatively, the separating agent includes a polyvinyl acetal resin having open cell structure and having an average pore size of from about 10 to about 1000 micrometers as a first element, and a layer of porous calcium phosphate granules having an average granule size of from about 10 to about 2000 micrometers as a second element applied onto the first element. The separating agents may be used in a separator, and may be employed in separating methods.
    Type: Grant
    Filed: February 3, 1994
    Date of Patent: June 11, 1996
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Sumiaki Tsuru, Takeshi Ichitsuka, Akihiko Yokoo, Tsuneo Hiraide
  • Patent number: RE35340
    Abstract: Column packing materials useful in applications such as liquid chromatography, as well as a process for producing such a packing material are described. A first aspect of the invention concerns a column packing material composed of a spherical substrate having a coating of a calcium phosphate based compound on the surface thereof.A second aspect of the invention concerns a packing material comprising porous calcium phosphate based granules having open pores with an average pore size of from 0.01 to 20 .mu.m, said granules being composed of crystalline particles with an average size of from 0.1 to 10 .mu.m.A third aspect of the invention concerns a spherical packing material for liquid chromatography comprising spherical particles of at least one material selected from the group consisting of Ca.sub.10 (PO.sub.4).sub.6 (OH).sub.2, Ca.sub.3 (PO.sub.4).sub.2, Ca.sub.2 P.sub.2 O.sub.7, Ca(PO.sub.3).sub.2, Ca.sub.10 (PO.sub.4).sub.6 F.sub.2 and Ca.sub.10 (PO.sub.4).sub.6 Cl.sub.
    Type: Grant
    Filed: August 13, 1993
    Date of Patent: October 1, 1996
    Assignee: Asahi Kogaku Kogyo K.K.
    Inventors: Takeshi Ichitsuka, Tetsuro Ogawa, Katsumi Kawamura, Masaya Sumita, Akihiko Yokoo