The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 07, 2007
Filed:
Apr. 23, 2002
Makoto Satsuki, Okayama, JP;
Natsuko Ishida, Okayama, JP;
Sadaharu Suga, Okayama, JP;
Hisayoshi Fujikawa, Aichi, JP;
Yasunori Taga, Aichi, JP;
Makoto Satsuki, Okayama, JP;
Natsuko Ishida, Okayama, JP;
Sadaharu Suga, Okayama, JP;
Hisayoshi Fujikawa, Aichi, JP;
Yasunori Taga, Aichi, JP;
Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo, Okayama, JP;
Kabushiki Kaisha Toyota Jidoshokki, Aichi, JP;
Abstract
An organic electroluminescent (EL) device which contains a novel coumarin derivative composed of a coumarin ring, a naphthalene ring with one or more hydrocarbon groups, and a five-membered hetero ring condensed with the naphthalene ring so as to give an electronic resonance through the coumarin and naphthalene rings. The coumarin derivative emits a visible luminescence with a satisfactory color purity, which consistently continues over a long period of time even at an elevated temperature when used in such an organic device.