Patents by Inventor Kunihide Oka

Kunihide Oka 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).

  • Alpha crystals of tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl]methane which have good flowability and method of producing same
    Patent number: 5117040
    Abstract: The invention provides alpha crystals of tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxymethyl]methane that occur as round granular crystals with high purity, uniform grain size, narrow grain size distribution and good flowability.
    Type: Grant
    Filed: June 5, 1990
    Date of Patent: May 26, 1992
    Assignee: Yoshitomi Pharmaceutical Industries, Ltd.
    Inventors: Masayoshi Marutani, Fumihide Izumi, Kunihide Oka
  • Individual .alpha.-form particle crystals of tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxymethyl]methane and process for its production
    Patent number: 5089655
    Abstract: Novel individual .alpha.-form particle crystals of tetrakis[3-(3,5,-di-t-butyl-4-hydroxyphenyl)propionyloxymethyl]methane and process for its production are disclosed.
    Type: Grant
    Filed: September 6, 1989
    Date of Patent: February 18, 1992
    Assignee: Yoshitomi Pharmaceutical Industries, Ltd.
    Inventors: Takanori Miura, Masanori Kohara, Kunihide Oka
  • Process for the production of ester compounds
    Patent number: 5081280
    Abstract: In producing ester compound useful as an antioxidant for organic materials which are represented by the formula: ##STR1## wherein R.sup.1 and R.sup.2 are the same or different and represent hydrogen or straight or branched chain alkyl radicals containing 1-8 carbon atoms, Z is an organic radical derived from an n-hydroxy alcohol, and n denotes an integer of 1 to 4, by transesterification, monoalkyltin compounds are used as a catalyst, whereby the ester compounds can be produced with high quality and in high yields.
    Type: Grant
    Filed: March 7, 1989
    Date of Patent: January 14, 1992
    Assignee: Yoshitomi Pharmaceutical Industries, Ltd.
    Inventors: Koichi Takee, Masayoshi Gohbayashi, Kunihide Oka
  • N-octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate with a novel crystalline form
    Patent number: 4950780
    Abstract: Novel crystalline form of n-octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate with improved transportability, measurability and workability is disclosed.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: August 21, 1990
    Assignee: Yoshitomi Pharmaceutical Industries, Ltd.
    Inventors: Masaya Tanaka, Masayoshi Gohbayashi, Kunihide Oka
  • Process for the production of penicillanic acid compounds
    Patent number: 4942229
    Abstract: An improved process for the production of penicillic acid compounds, especially chloromethyl ester of penicillin G, penicillin V or sulbactam is disclosed.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: July 17, 1990
    Assignee: Yoshitomi Pharmaceutical Industries, Ltd.
    Inventors: Kazumi Saeki, Masami Hirano, Kunihide Oka, Kazuto Tsukinuki, Setsuo Oikawa