Patents by Inventor Akio Tadokoro

Akio Tadokoro 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).

  • Patent number: 5028513
    Abstract: The present invention provide a process for producing printed circuit boards which comprises the steps of(a) roughening a surface of a copper layer formed on an insulating board.(b) coating the roughened surface of copper layer with a photo-resist layer containing a sublimable copper-corrosion inhibitor, exposing the resist layer selectively to actinic rays according to a circuit pattern to form, and developing the resulting resist layer, thereby forming plating-resist coats on circuit-negative pattern portions of the copper layer,(c) heat-treating the plating-resist coats,(d) plating chemically the circuit-corresponding portion with copper,(e) removing the plating-resist coats, and(f) removing the copper layer except the circuit-corresponding portion thereof.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: July 2, 1991
    Assignees: Hitachi, Ltd., Hitachi Chemical Co., Ltd.
    Inventors: Kanji Murakami, Mineo Kawamoto, Akio Tadokoro, Haruo Akahoshi, Toshikazu Narahara, Ritsuji Toba, Toshiaki Ishimaru, Nobuyuki Hayashi, Motoyo Wajima
  • Patent number: 4876177
    Abstract: A process for producing a printed circuit board, which comprises the steps of forming a layer comprising a photosensitive resin composition on an insulating substrate having on its surface an adhesive layer adherent to a metal being subsequently plated thereon; exposing said layer comprising a photosensitive resin composition to an actinic radiation in a manner so as to form on said layer a negative pattern of a conductor circuit pattern and to semicure said negative pattern to an extent sufficient to keep it from erosion by a plating solution; developing by dissolving away with a solvent the uncured areas not exposed to said actinic radiation, thereby to form a plating resist on the areas of said negative pattern; chemically plating said conductor circuit pattern areas not covered with said plating resist, thereby to form a conductor circuit; and carrying out a curing treatment to cure completely said resist.
    Type: Grant
    Filed: September 8, 1987
    Date of Patent: October 24, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Haruo Akahoshi, Kanji Murakami, Mineo Kawamoto, Akio Tadokoro, Toyofusa Yoshimura
  • Patent number: 4632852
    Abstract: In a process for electroless copper plating in an electroless copper plating solution containing a copper salt, a complexing agent for the copper salt, a reducing agent for the copper salt, and a pH-adjusting agent, a plating film having distinguished mechanical properties can be obtained by adding at least one of soluble inorganic silicon compounds and soluble inorganic germanium compounds and conducting the electroless copper plating by injecting an oxygen-containing gas into the plating solution or by adding an oxidizing agent to the plating solution or by both injection or the oxygen-containing gas and addition of the oxidizing agent thereto. The stability of the electroless copper plating solution can be maintained better thereby and substantially thick plating is possible.
    Type: Grant
    Filed: June 18, 1985
    Date of Patent: December 30, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Haruo Akahoshi, Kanji Murakami, Mineo Kawamoto, Motoyo Wajima, Rituji Toba, Shoji Kawakubo, Akio Tadokoro