Patents by Inventor Kenji Kunikata

Kenji Kunikata 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).

  • Publication number: 20100121020
    Abstract: The invention provides 3,3?-diamino-5,5?-diphenyl-4,4?-biphenyldiol which is useful as a monomer for a high-performance polymer, particularly a polymer satisfying performances highly required in the semiconductor field such as polybenzoxazole, polyimide or the like and 3,3?-dinitro-5,5?-diphenyl-4,4?-biphenyldiol as a raw material thereof. Also, the invention provides a polybenzoxazole having a repeating unit represented by the following formula (1): (wherein R is a bivalent dicarboxylic acid residue).
    Type: Application
    Filed: March 18, 2008
    Publication date: May 13, 2010
    Applicant: NIPPONKAYAKU KABUSHIKIKAISHA
    Inventors: Kenji Kunikata, Taihei Koumoto, Kenji Sekine
  • Patent number: 5977413
    Abstract: Disclosed is a method for producing bis(3-amino-4-hydroxyphenyl) compounds, which comprises reducing bis(3-nitro-4-hydroxyphenyl) compounds with hydrazines in the presence of a catalyst. The method produces bis(3-amino-4-hydroxyphenyl) compounds of high quality under mild conditions at high yields. The products can be isolated and purified in a simple manner to have a higher purity. The method is suitable to industrial-scale production of the products.
    Type: Grant
    Filed: July 28, 1998
    Date of Patent: November 2, 1999
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Jun-ichiro Tomaru, Kenji Kunikata, Masaki Fujimoto
  • Patent number: 5516934
    Abstract: The present invention aims at providing a process for economically producing mono-p-nitrobenzyl malonate while recovering the excessive malonic acid and treating the by-product. The process of the present invention for producing mono-p-nitrobenzyl malonate comprises reacting p-nitrobenzyl-alcohol with malonic acid in an organic solvent, which may contain di-p-nitrobenzyl malonate if necessary, cooling the reaction mixture thus obtained to 35.degree. to 100.degree. C., separating the malonic acid thus precipitated and treating the reaction mixture with a basic aqueous solution at 35.degree. to 80.degree. C. The di-p-nitrobenzyl malonate formed as the by-product is effectively utilized by hydrolyzing or reacting with malonic acid to thereby give mono-p-nitrobenzyl malonate.
    Type: Grant
    Filed: June 27, 1995
    Date of Patent: May 14, 1996
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventor: Kenji Kunikata
  • Patent number: 4425270
    Abstract: A reactive disazo compound which, in the free acid form, is represented by the formula: ##STR1## wherein R.sub.1 is H, Cl or SO.sub.3 H, R.sub.2 is H, CH.sub.3 or SO.sub.3 H, X is .beta.-sulfatoethyl, .beta.-thiosulfatoethyl, .beta.-phosphatoethyl or vinyl, Y is Cl or F, Z is Cl, F or Z.sub.1, Z.sub.1 is amino; mono- or dialkylamino having 1 to 4 carbon atoms which may be substituted by hydroxy, carboxy or sulfo; morpholino; anilino which may be substituted by halogen, lower alkyl, lower alkoxy, carboxy or sulfo; N-methylanilino, naphthylamino or sulfo-substituted naphthylamino; alkoxy having 1 to 4 carbon atoms which may be substituted by lower alkoxy; phenoxy; alkylthio having 1 to 4 carbon atoms which may be substituted by hydroxy; phenylthio, and Q is N, C--Cl or C--F when Z is Cl or F and N when Z is Z.sub.1. These compounds are used for dyeing or printing cellulosic fibers.
    Type: Grant
    Filed: April 2, 1981
    Date of Patent: January 10, 1984
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Yasushi Yamada, Kenji Kunikata, Hideo Otake