Patents by Inventor Youngkoo Kim

Youngkoo Kim 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).

  • Diamine hole transport agent and organic electroluminescent device containing same
    Patent number: 6342637
    Abstract: A novel diamine compound of formula (I) of the present invention having a high glass transition temperature is useful as an improved hole transport agent, and an organic electroluminescent device containing the diamine compound of formula (I) has good thermal and mechanical stabilities, and prolonged lifetime.
    Type: Grant
    Filed: August 9, 2001
    Date of Patent: January 29, 2002
    Assignee: Nessdisplay Co., Ltd.
    Inventors: Ki-jong Han, Youngkoo Kim, Jae-Gyoung Lee, Dong-Kwon Choi