Patents by Inventor Tokuichi Kamada

Tokuichi Kamada 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).

  • Silver master plate recovery solution
    Patent number: 4965168
    Abstract: A silver master plate recovery solution for a silver salt photographic plate for offset printing is disclosed which comprises (a) a hydrazine component for reducing the silver oxide layer of an image area, (b) a quaternary ammonium salt cationic activator and (c) water. The mixing ratio of the quaternary ammonium salt cationic activator is 3.0 to 20.0 wt % on the basis of the hydrazine component. The silver master plate recovery solution reduces the silver oxide layer of the image area of a silver salt photographic plate which has passed the stock time, thereby recovering the ink receptivity of the image area.
    Type: Grant
    Filed: June 2, 1989
    Date of Patent: October 23, 1990
    Assignee: Nikken Chemical Laboratory Co., Ltd.
    Inventors: Hajime Yoshida, Tokuichi Kamada, Osamu Kainuma