Patents by Inventor Yoshiki Kametani

Yoshiki Kametani 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 N,N-disubstituted p-phenylenediamine derivative sulfate
    Patent number: 5475140
    Abstract: 4-Amino-3-methyl-N-ethyl-N-(.beta.-hydroxyethyl)-aniline sulfate which is used particularly as a developer for color photography can be easily produced in high yield and high quality by nitrosating N-ethyl-N-(.beta.-hydroxyethyl)-m-toluidine by use of an alkyl nitrite in a homogeneous alcohol solution containing sulfuric acid in an amount of about 0.5 to about 1 mole per mole of N-ethyl-N-(.beta.-hydroxyethyl)-m-toluidine, and then reducing the nitrosation product in an aqueous alcohol solution after or without isolation of the nitrosation product.
    Type: Grant
    Filed: April 19, 1994
    Date of Patent: December 12, 1995
    Assignee: Wako Pure Chemical Industries, Ltd.
    Inventors: Takehiko Iritani, Ryohiko Kinoshita, Yoshiki Kametani