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:
Nov. 25, 2025
Filed:
Mar. 04, 2019
Nippon Steel Chemical & Material Co., Ltd., Tokyo, JP;
Yuta Sagara, Tokyo, JP;
Masashi Tada, Tokyo, JP;
NIPPON STEEL CHEMICAL & MATERIAL CO., LTD., Tokyo, JP;
Abstract
Provided is a thermally activated delayed fluorescent emission-type organic electroluminescent device (organic EL device) having a low driving voltage, high luminous efficiency, and a long lifetime. The organic EL device is a delayed fluorescent emission-type organic EL device including one or more light-emitting layers between an anode and a cathode opposite to each other, wherein at least one of the light-emitting layers contains a para-biphenylcarbazole compound-type host material represented by the general formula (1), and an indolocarbazole compound-type thermally activated delayed fluorescent light-emitting material including an indolocarbazole ring in a molecule thereof.