Patents by Inventor Masaya Sumita

Masaya Sumita 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).

  • Packing material for liquid chromatography
    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
  • Process for the production of spherical particles of ceramics
    Patent number: 5030391
    Abstract: A process for the production of spherical ceramics particles which are useful as a filling material for osseous defects, as a carrier for drug delivery system and as a packing material for a liquid chromatography includes the steps of forming a first spherical particle consisting of a particulate ceramics-based core and a shell of polymeric material covering the core by using microcapsule technology, and removing the shell from the first spherical ceramic particle to obtain the sperical particles.
    Type: Grant
    Filed: September 13, 1988
    Date of Patent: July 9, 1991
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Masaya Sumita, Miyuki Kakinuma
  • Method for producing porous sintered apatite material
    Patent number: 4919751
    Abstract: A method for producing a porous sintered apatite material comprising the steps of:sintering a calcium-excess apatite at 800.degree. C. or more so as to form a sintered apatite material having a calcium oxide content of from 0.5 to 60 wt % by phase separation of calcium oxide; andremoving the calcium oxide from the sintered apatite material so as to form a porous sintered apatite material.
    Type: Grant
    Filed: February 1, 1989
    Date of Patent: April 24, 1990
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Masaya Sumita, Hitoshi Akiyama
  • Process for producing calcium phosphate
    Patent number: 4897250
    Abstract: A process for producing a calcium phosphate comprising the steps of (a) dissolving at least one member selected from the group consisting of calcium hydroxide and calcium oxide in water with at least one member selected from the group consisting of a sugar, a sugar alcohol, and a polyhydric alcohol; (b) and adding phosphoric acid to the solution obtained to precipitate a calcium phosphate.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: January 30, 1990
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Masaya Sumita