Patents by Inventor Hiroko Wakui

Hiroko Wakui 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).

  • Projection tube whose coolant contains an ethylene oligomer
    Patent number: 4717853
    Abstract: Disclosed is a projection tube containing a coolant comprising a liquid mixture of ethylene glycol and water filled in the space between a phosphor screen panel and a transparent face panel which is set up at a certain distance in front thereof, wherein the coolant is incorporated with 10 ppm to 20 wt. % of an ethylene oligomer. The present projection tube is an excellent product free from a decrease in transmittance due to the coloring of the coolant in operation at a high temperature.
    Type: Grant
    Filed: March 6, 1986
    Date of Patent: January 5, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Masayoshi Ezawa, Hiroko Wakui, Shigeru Wakana, Toshikazu Morishita, Akira Misumi