| CPC H10K 85/657 (2023.02) [H10K 85/654 (2023.02); H10K 85/6572 (2023.02); H10K 85/658 (2023.02); H10K 50/11 (2023.02)] | 22 Claims |

|
1. An organic electroluminescence device comprising:
an anode;
a cathode; and
an emitting layer, wherein
the emitting layer comprises a first compound, a second compound, and a third compound,
the first compound, the second compound, and the third compound are different from each other,
the first compound is a fluorescent compound,
the second compound is a delayed fluorescent compound, and
the first compound, the second compound, and the third compound satisfy numerical formulae (Numerical Formula 1), (Numerical Formula 2), (Numerical Formula 3), and (Numerical Formula 4) below:
|Af(M1)−Af(M2)|≤0.40 eV (Numerical Formula 1):
Ip(M2)≥5.75 eV (Numerical Formula 2):
|Ip(M2)−Ip(M3)|≤0.25 eV (Numerical Formula 3):
S1(M3)≥S1(M2) (Numerical Formula 4):
where Af(M1) is an affinity of the first compound,
Af(M2) is an affinity of the second compound,
Ip(M2) is an ionization potential of the second compound,
S1(M2) is a lowest singlet energy of the second compound,
Ip(M3) is an ionization potential of the third compound, and
S1(M3) is a lowest singlet energy of the third compound.
|