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:
Sep. 01, 2009
Filed:
Sep. 21, 2004
Osamu Yoshitake, Kitakyushu, JP;
Hiroshi Miyazaki, Kitakyushu, JP;
Daisuke Suzaki, Niigata, JP;
Yu Yamada, Tokyo, JP;
Osamu Yoshitake, Kitakyushu, JP;
Hiroshi Miyazaki, Kitakyushu, JP;
Daisuke Suzaki, Niigata, JP;
Yu Yamada, Tokyo, JP;
Nippon Steel Chemical Co., Ltd., Tokyo, JP;
Abstract
This invention provides an organic electroluminescent element (organic EL element) utilizing phosphorescence which emits light efficiently with high luminance at low current density, shows good driving stability and is applicable to display devices such as flat panel displays and illuminating devices. The element comprises an anode, organic layers and a cathode piled one upon another on a substrate, at least one of the organic layers is a light-emitting layer containing a host material and a dopant material and a pyrazole-derived compound having 2-4 pyrazole structures represented by the following formula I in the same molecule is used as said host material; wherein, Ar-Arare independently hydrogen or substituted or unsubstituted aromatic hydrocarbon groups and at least one of Ar-Aris a group other than hydrogen.