Patents by Inventor Youko Yamashita

Youko Yamashita 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).

  • O-quinonediazide photosensitive composition containing s-triazine compound, novolak resin, vinyl-based polymer and a dye
    Patent number: 5338643
    Abstract: Disclosed herein is a photosensitive composition comprising:(A) 5 to 60 wt % of an o-quinonediazide compound;(B) 0.05 to 10 wt % of an s-triazine compound(C) 0.01 to 10 wt % of a dye for changing the color tone by the interaction with the photodecomposition product of the said s-triazine compound;(D) 30 to 90 wt % of a novolak resin containing less than 5 wt % of phenols; and(E) 1 to 60 wt % of a vinyl-based polymer having at least a phenolic hydroxyl group.
    Type: Grant
    Filed: December 23, 1992
    Date of Patent: August 16, 1994
    Assignees: Mitsubishi Kasei Corporation, Konica Corporation
    Inventors: Daisuke Kanazawa, Mitsuru Sasaki, Toshiyuki Urano, Youko Yamashita, Shinichi Matsubara