Patents by Inventor Yoshiko Ikeno

Yoshiko Ikeno 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 producing substituted phthalic acid compounds
    Patent number: 4684737
    Abstract: A process for producing a substituted phthalic acid which comprises heating a substituted tetrahydrophthalic acid compound having a substituent in at least one of the 3-, 4-, 5- and 6-positions in the presence of sulfur to dehydrogenate it, and heat-treating the product in the presence of water optionally together with an organic solvent. As required, the heat-treated product is dehydrocyclized to form a substituted phthalic acid anhydride.
    Type: Grant
    Filed: August 17, 1984
    Date of Patent: August 4, 1987
    Assignee: Nippon Zeon Co., Ltd.
    Inventors: Hiroshi Horino, Michiro Ohnaka, Atsushi Hayashi, Yoshiko Ikeno