Organic electroluminescent device and display device

1. An organic electroluminescent device, comprising:

a substrate;

an anode comprising an inorganic conducting material above the substrate;

a cathode comprising an inorganic conducting material above the substrate;

an organic emission functional layer interposed between the anode and the cathode, the organic emission functional layer comprising an organic emissive layer;

an organic electrode film comprising (a) a first layer of a polycyclic aromatic hydrocarbon compound having a backbone of 3- to 7-membered rings and (b) a second layer of a benzoimidazole derivative having a substituent in the benzene ring, the organic electrode film being provided such that the first layer is disposed in contact with an outer side of the cathode or the second layer is disposed in contact with an outer side of the anode; and

an electrode wire on an outer side of the organic electrode film, the electrode wire being above the organic electrode film, the anode, the cathode and the substrate.

2. The organic electrolurninescent device of claim 1 , wherein the backbone of the polycyclic aromatic hydrocarbon compound is selected from anthracene, pyrene, benzopyrene, chrysene, naphthacene, benzonaphthacene, dibenzonaphthacene, perylene, and coronene.

3. The organic electroluminescent device of claim 2 , wherein the polycyclic aromatic hydrocarbon is an anthracene derivative represented by the following general formula ( 1 )

wherein R 1 to R 6 each independently represent hydrogen, halogen, a hydroxyl group, an optionally substituted carbonyl group of 20 or less carbon atoms, an optionally substituted carbonyl ester group of 20 or less carbon atoms, an optionally substituted alkyl group of 20 or less carbon atoms, an optionally substituted alkenyl group of 20 or less carbon atoms, an optionally substituted alkoxyl group of 20 or less carbon atoms, a cyano group, a nitro group, an optionally substituted silyl group of 30 or less carbon atoms, an optionally substituted aryl group of 30 or less carbon atoms, an optionally substituted heterocyclic group of 30 or less carbon atoms, or an optionally substituted amino group of 30 or less carbon atoms.

4. The organic electroluminescent device of claim 1 , wherein the benzoimidazole derivative is represented by the following general formula (2)

wherein:

A 1 and A 2 each independently represents a hydrogen atom, an optionally substituted aryl group of 60 or less carbon atoms, an optionally substituted heterocyclic group, an optionally substituted alkyl group of 1 to 20 carbon atoms, or an optionally substituted alkoxy group of 1 to 20 carbon atoms;

B represents an optionally substituted arylene group of 60 or less carbon atoms, an optionally substituted pyridinylene group, an optionally substituted quinolinylene group, or an optionally substituted fluorenylene group; and

Ar represents an optionally substituted aryl group of 6 to 60 carbon atoms, an optionally substituted heterocyclic group of 3 to 60 carbon atoms, an optionally substituted alkyl group of 1 to 20 carbon atoms, or an optionally substituted alkoxy group of 1 to 20 carbon atoms.

5. The organic electroluminescent device of claim 1 , wherein the anode or the cathode in contact with the organic electrode film is provided on the side from which light is drawn.

6. The organic electroluminescent device of claim 5 , wherein the light produced by the organic emissive layer is resonated between the anode and the cathode so as to be drawn from one of the anode and the cathode.

7. A display device comprising a plurality of organic electroluminescent devices arrayed on a substrate, the organic electroluminescent devices each including:

an anode comprising an inorganic conducting material above the substrate;

a cathode comprising an inorganic conducting material above the substrate;

an organic emission functional layer interposed between the anode and the cathode, the organic emission functional layer comprising an organic emissive layer;

an organic electrode film comprising (a) a first layer of a polycyclic aromatic hydrocarbon compound having a backbone of 3- to 7-membered rings and (b) a second layer of a benzoimidazole derivative having a substituent in the benzene ring, the organic electrode film being provided such that the first layer is disposed in contact with an outer side of the cathode or the second layer is disposed in contact with an outer side of the anode; and

an electrode wire on an outer side of the organic electrode film, the electrode wire being above the organic electrode film, the anode, the cathode and the substrate.

8. The display device of claim 7 , wherein the backbone of the polycyclic aromatic hydrocarbon compound is selected from anthracene, pyrene, benzopyrene, chrysene, naphthacene, benzonaphthacene, dibenzonaphthacene, perylene, and coronene.

9. The display device of claim 8 , wherein the polycyclic aromatic hydrocarbon is an anthracene derivative represented by the following general formula (1).

wherein R 1 to R 6 each independently represent hydrogen, halogen, a hydroxyl group, an optionally substituted carbonyl group of 20 or less carbon atoms, an optionally substituted carbonyl ester group of 20 or less carbon atoms, an optionally substituted alkyl group of 20 or less carbon atoms, an optionally substituted alkenyl group of 20 or less carbon atoms, an optionally substituted alkoxyl group of 20 or less carbon atoms, a cyano group, a nitro group, an optionally substituted silyl group of 30 or less carbon atoms, an optionally substituted aryl group of 30 or less carbon atoms, an optionally substituted heterocyclic group of 30 or less carbon atoms, or an optionally substituted amino group of 30 or less carbon atoms.

10. The display device of claim 7 , wherein the benzoimidazole derivative is represented by the following general formula (2)

wherein:

A 1 and A 2 each independently represents a hydrogen atom, an optionally substituted aryl group of 60 or less carbon atoms, an optionally substituted heterocyclic group, an optionally substituted alkyl group of 1 to 20 carbon atoms, or an optionally substituted alkoxy group of 1 to 20 carbon atoms;

B represents an optionally substituted arylene group of 60 or less carbon atoms, an optionally substituted pyridinylene group, an optionally substituted quinolinylene group, or an optionally substituted fluorenylene group; and

Ar represents an optionally substituted aryl group of 6 to 60 carbon atoms, an optionally substituted heterocyclic group of 3 to 60 carbon atoms, an optionally substituted alkyl group of 1 to 20 carbon atoms, or an optionally substituted alkoxy group of 1 to 20 carbon atoms.

11. The display device of claim 7 , wherein the anode or the cathode in contact with the organic electrode film is provided on the side from which light is drawn.

12. The display device of claim 11 , wherein the light produced by the organic emissive layer is resonated between the anode and the cathode so as to be drawn from one of the anode and the cathode.