The invention relates to compounds which are suitable for use in electronic devices, and to electronic devices, in particular organic electroluminescent devices, containing said compounds.

The present disclosure provides an organic compound of following Formula, and an organic light emitting diode and an organic light emitting display device including the organic emitting compound. ##STR00001##

An organic EL device includes: an anode, a cathode, and an emitting layer, in which the emitting layer contains a first compound of a formula (1), a second compound of a formula (2), and a third compound that exhibits delayed fluorescence, and singlet energies S.sub.1 of the first compound, the second compound, and the third compound satisfy Numerical Formula 1 and Numerical Formula 2. ##STR00001## In the formula (1), A represents a group of a formula (a1) or the like, L represents a linking group or the like, and B represents an aryl group or the like. The first compound of the formula (1) has no carbonyl group. In the formula (2), Y.sub.21 to Y.sub.26 each independently represent an N atom, CR.sub.A, or the like. R.sub.A represents a substituent, a group of a formula (2A), or the like.

An organic light emitting diode (OLED) including at least one emitting material layer (EML) disposed between two electrodes and comprising a first compound including a fused hetero aromatic ring with at least one nitrogen atom and a second compound of a boron-based compound and an organic light emitting device including the OLED is disclosed. The first compound and the second compound may be the same emitting material layer or adjacently disposed emitting material layers. The OLED can lower its driving voltage and improve its luminous efficiency using the first and second compounds with adjusting their energy levels.