Patents by Inventor Hiroko Takehawa

Hiroko Takehawa 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).

  • Measurement method, adjustment method and adjustment system for the concentrations of ingredients in electroless plating solution
    Patent number: 5106413
    Abstract: Disclosed herein are a method for measuring the concentration of one or more ingredients in an electroless plating solution containing at least one metal ingredient, anions and a reducing agent, and concentration adjustment method and system making use of the method. The method features measurement of the concentration of the reducing agent after replacing the anions with anions of a different type which does not affect the measurement of the concentration of the reducing agent. The measurement of the concentration of the metal ingredient can be conducted by atomic absorption spectrometry or plasma spectro.metry, while that of the reducing agent can be performed by ultraviolet absorption spectroscopy or electrochemical quantitative analysis.
    Type: Grant
    Filed: February 1, 1991
    Date of Patent: April 21, 1992
    Assignee: Hitachi, Ltd.
    Inventor: Hiroko Takehawa