Patents by Inventor Yumi Hatta

Yumi Hatta 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).

  • Process for preparation of 2-substituted 1,4-naphthoquinone
    Patent number: 5329026
    Abstract: A process for preparation of a 2-substituted-1,4-naphthoquinone which comprises oxidizing a 2-substituted naphthalene to obtain reaction products comprising a 2-substituted-1,4-naphthoquinone and a 6-substituted-1,4-naphthoquinone; adding a diene compound to the reaction products and heating the mixture to form a Diels-Alder reaction adduct between the diene compound and the 6-substituted-1,4-naphthoquinone in the reaction products; and separating the 2-substituted-1,4-naphthoquinone from the adduct.
    Type: Grant
    Filed: November 28, 1990
    Date of Patent: July 12, 1994
    Assignee: Nippon Shokubai Kagaku Kogyo Co., Ltd.
    Inventors: Noboru Sugishima, Noriaki Ikeda, Yasushi Fujii, Ryuji Aoki, Yumi Hatta