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. 29, 2020
Filed:
Jul. 26, 2019
Canon Kabushiki Kaisha, Tokyo, JP;
Tomokazu Kotake, Ebina, JP;
Hirokazu Miyashita, Ebina, JP;
Itaru Takaya, Atsugi, JP;
Takayuki Ito, Kawasaki, JP;
Koji Ishizuya, Fujisawa, JP;
Norifumi Kajimoto, Zama, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
A white organic electroluminescent (EL) element includes, in sequence, an anode, a first light-emitting layer that is a blue-light-emitting layer, a hole-blocking layer, an electron transport layer, and a cathode. The hole-blocking layer is adjacent to the first light-emitting layer and the electron transport layer and formed of a hydrocarbon. The electron transport layer is formed of a nitrogen-containing heterocyclic compound. The first light-emitting layer contains a first host and a first dopant that emits blue fluorescent light. Relations (a), (b), and (c) are satisfied.LUMO(1)>LUMO(1)  (a)0.1<(ETL)/(HBL)<0.7  (b)90 nm≤()=(HBL)+(ETL)<150 nm  (c)