申请人:KYUSHU UNIVERSITY, NATIONAL UNIVERSITY CORPORATION
公开号:US20210202864A1
公开(公告)日:2021-07-01
An organic electroluminescent device having an anode, a cathode, and a light-emitting layer between the anode and the cathode, wherein the light-emitting layer contains at least a first organic compound, a second organic compound and a third organic compound satisfying the following formula (A), the second organic compound is a delayed fluorescent material, and the third organic compound is a light-emitting material, has a high light emission efficiency. Formula (A): E
S1
(A)>E
S1
(B)>E
S1
(C) wherein E
S1
(A), E
S1
(B) and E
S1
(C) each represent a lowest excited singlet energy level of the first organic compound, the second organic compound and the third organic compound, respectively.