Patents by Inventor Keiji Kamegawa

Keiji Kamegawa 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).

  • Good aesthetic artificial dental materials by calcium phosphate glass-ceramic
    Patent number: 4626514
    Abstract: Dental materials using calcium phosphate glass-ceramics and having the color tone with high approximation to that of natural teeth. In those dental materials, calcium phosphate composite, nickel oxide and one or more other type of compounds selected from oxides of iron, manganese, cerium, titanium and tungsten, are contained as coloring component. Also, if necessary, Al.sub.2 O.sub.3 and/or SiO.sub.2 is contained as a color assisting agent in that composite. The calcium phosphate glass-ceramic according to this invention consists of the same components as that of natural teeth. Besides, it is possible to adjust the color tone delicately to match with the color tone of each individual`s teeth. Moreover, the coloring components are incorporated in crystals of calcium phosphate. Consequently, they cause no elution during use and are therefore ideal as dental material.
    Type: Grant
    Filed: March 27, 1986
    Date of Patent: December 2, 1986
    Assignee: Kyushu Refractories Co., Ltd.
    Inventors: Akira Watanabe, Yoshimitsu Takeuchi, Hiroyasu Tokuda, Seiji Kihara, Yasuhiro Makino, Keiji Kamegawa