Patents by Inventor Hidekaku Yoshimatsu

Hidekaku Yoshimatsu 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: 5190740
    Abstract: A method for producing an oxide useful as a starting material for making soft ferrites comprised mainly of iron, zinc and at least one metal selected from manganese, magnesium, nickel and copper is described. In the method, while chlorides of metals other than zinc are roasted for oxidation to produce a composite oxide, zinc oxide is added during the roasting. This method ensures addition of zinc oxide at high yield without use of zinc chloride having a high vapor pressure. The resultant oxide for ferrites has desired ratios of metal constituents and contains spinel ferrites which are intermediate products with zinc oxide being uniformly dispersed. The use of the starting oxide leads to omission of a calcination step and a powder mixing step in the production process of ferrites. Ferrites with good quality can be obtained by direct sintering.An alternative method using zinc chloride instead of zinc oxide is also described which can provide an equivalent oxide for making ferrites.
    Type: Grant
    Filed: December 7, 1990
    Date of Patent: March 2, 1993
    Assignee: Kawasaki Steel Corporation
    Inventors: Tetsu Narutani, Hidekaku Yoshimatsu, Masakatsu Yamazaki, Masao Tsuzaki, Fumiaki Yoshikawa, Katashi Takaki