Patents by Inventor Kenji Koushiro

Kenji Koushiro 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).

  • Method of manufacturing a stamper for formation of optical information carrying disk
    Patent number: 5015338
    Abstract: A method for preparing a stamper comprises the steps of forming a first electro-conductive layer and a second electro-conductive layer on a photoresist layer carrying pits through a physical vapor deposition before the electroforming of a stamper layer. The second electro-conductive layer is effective for preventing the first electro-conductive layer from corroding during the electroforming step because of the active treatment solution for the electroforming and also avoids the corrosion of the first electro-conductive layer even in the storage period before the particular electroforming step.
    Type: Grant
    Filed: May 2, 1989
    Date of Patent: May 14, 1991
    Assignee: Pioneer Electronic Corp.
    Inventors: Hirotoshi Tabuchi, Osamu Kumasaka, Katsura Ito, Kenji Koushiro