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:
Feb. 18, 2020
Filed:
Dec. 22, 2015
Beijing Visionox Technology Co., Ltd., Beijing, CN;
Tsinghua University, Beijing, CN;
Lian Duan, Beijing, CN;
Yong Qiu, Beijing, CN;
Guohui Zhang, Beijing, CN;
Man Li, Beijing, CN;
Dongdong Zhang, Beijing, CN;
Yonglan Hu, Beijing, CN;
BEIJING VISIONOX TECHNOLOGY CO., LTD., Beijing, CN;
TSINGHUA UNIVERSITY, Beijing, CN;
Abstract
The present invention discloses an organic electroluminescence device, comprising a luminescent layer, wherein, a host material of the luminescent layer comprises a thermally activated delayed fluorescence material, the host material is doped by a dye, and the dye comprises at least one phosphorescent dye. The present invention employs a thermally activated delayed fluorescence material, whose difference between the triplet state energy level and the singlet state energy level (ΔE) is relatively small. The present invention employs the material as the phosphorescence host, so part of the triplet state exciton level transfers to the singlet state excitons, and the amount of the overall triplet state excitons is smaller. Therefore, the concentration of the triplet state excitons decreases, and the recombination region becomes narrower, which effectively reduces the probability of excitons entering the charge transport layer, and at the same time the narrowing of the recombination region effective prevents the diffusion of N-type dopants into the exciton recombination region. Additionally, by employing the host material, the device corresponds to a low working voltage.