| 摘要 |
An organic EL device (1) includes a pair of electrodes (3,4) and an organic compound layer (10) between pair of electrodes (3,4). The organic compound layer (10) includes an emitting layer (5) including a first material and a second material. The second material is a fluorescent material. Singlet energy EgS(H) of the first material and singlet energy EgS(D) of the second material satisfy a relationship of the following formula (1). The first material satisfies a relationship of the following formula (2) in terms of a difference ”ST(H) between the singlet energy EgS(H) and an energy gap Eg 77K (H) at 77K.
[Formula 1] EgS H > EgS D
[Formula 2] ”ST H = EgS H - Eg 77 �¢ K H < 0.3 eV |
