An organic electroluminescence device (hereinafter, occasionally abbreviated as organic EL device) using an organic substance is highly expected to be used as an inexpensive solid-emitting full-color display device having a large area, and has been variously developed. In general, an organic EL device includes a pair of opposing electrodes and an emitting layer between the pair of electrodes. When an electrical field is applied to the opposing electrodes, electrons are injected from a cathode, and holes are injected from an anode. The electrons are then recombined with the holes in the emitting layer to yield an excited state, and energy generated when the excited state returns to a ground state is discharged as light.
As compared with an inorganic light-emitting diode, a typical organic EL device requires a high drive voltage, and the luminescence intensity and luminous efficiency thereof are low. Moreover, since the typical organic EL device is to undergo considerable performance degradation, it has not been in practical use.
Patent Literature 1 discloses a compound having a phenylene group at the center thereof, the phenylene group being bonded to a naphthyl group, an anthryl group or a phenanthrenyl group at one bond while being bonded to a phenyl group at the other bond. The compound has at least one bridge between the phenylene group at the center and the adjacent groups. Patent Literature 1 also discloses an organic EL device using the compound or a heterocyclic derivative of the compound.
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