Patents by Inventor Yasushi Ishihama

Yasushi Ishihama 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).

  • Photocurable resin composition, method of producing photo-cured shaped object, vacuum casting mold, vacuum casting method and novel urethane acrylate
    Patent number: 6017973
    Abstract: A photocurable resin composition comprising (A) at least one urethane di- or triacrylate, which is a novel compound, (B) a radical polymeriable compound, and (C) a photopolymerization initiator, the weight ratio of the urethane acrylate (A) to the radical polymerizable compound (B) being 65/35 to 25/75; a method of producing a photo-cured object by photo-curing the above composition; a vacuum casting mold obtained by the above method; and a vacuum casting method using the above mold.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: January 25, 2000
    Assignee: Teijin Seiki Company, Ltd.
    Inventors: Yorikazu Tamura, Tsuneo Hagiwara, Yasushi Ishihama, Minoru Kayanoki, Takakuni Ueno
  • Polymorphs of donepezil hydrochloride and process for production
    Patent number: 5985864
    Abstract: Donepezil hydrochloride, 1-benzyl-4-[(5,6-dimethoxy-1-indanon)-2-yl]methylpiperidine hydrochloride, is provided here in the form of four polymorphs which are stable against heat and humidity in the pharmaceutical use. They can be industrially produced. They are specified by peaks in X-ray powder diffraction pattern and absorption peaks in infrared absorption spectra in potassium bromide.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: November 16, 1999
    Assignee: Eisai Co., Ltd.
    Inventors: Akio Imai, Hideaki Watanabe, Takashi Kajima, Yasushi Ishihama, Akiyo Ohtsuka, Tomohide Tanaka, Yukio Narabu