Patent ID: 7466074

Claim:
An organic light-emitting device comprising a pair of electrodes including an anode and a cathode; and a light-emitting layer and a hole-transporting layer disposed between the pair of electrodes, an energy gap E 1 of a main component of the light-emitting layer and an energy gap E 2 of a main component of the hole-transporting layer satisfying the relationship of E 2 −E 1 ≦0.3 eV, wherein the hole-transporting layer comprises a second component in addition to the main component of the hole-transporting layer; (1) an energy of a lowest triplet excited state of the second component is less than an energy of a lowest triplet excited state of the main component of the hole-transporting layer; (2) a lowest unoccupied molecular orbital energy of the second component is higher than a lowest unoccupied molecular orbital energy of the main component of the light-emitting layer; and (3) the second component has an energy gap of 2.7 eV or more.