Organic electroluminescence element

• US 20060046098A1
• Filed: 10/07/2005
• Published: 03/02/2006
• Est. Priority Date: 03/27/2000
• Status: Active Grant

• Current Assignee: Idemitsu Kosan Company Limited
• Original Assignee: Idemitsu Kosan Company Limited
• Inventors: Hosokawa, Chishio
• Granted Patent: US 7,226,546 B2
• Time in Patent Office: Days
• US Class Current: 428/690
• CPC Class Codes: C09K 11/025 non-luminescent particle coatings or suspension media
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: C09K 2211/1007 Non-condensed systems
• CPC Class Codes: C09K 2211/1011 Condensed systems
• CPC Class Codes: C09K 2211/1014 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: C09K 2211/1029 containing one nitrogen atom as the heteroatom
• CPC Class Codes: C09K 2211/1033 with oxygen
• CPC Class Codes: C09K 2211/185 of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 2102/102 comprising tin oxides, e.g. fluorine-doped SnO2
• CPC Class Codes: H10K 2102/103 comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/171 Electron injection layers
• CPC Class Codes: H10K 50/828 Transparent cathodes, e.g. comprising thin metal layers
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: H10K 71/30 Doping active layers, e.g. electron transporting layers
• CPC Class Codes: H10K 71/60 Forming conductive regions or layers, e.g. electrodes
• CPC Class Codes: H10K 85/146 poly N-vinylcarbazol; Derivatives thereof
• CPC Class Codes: H10K 85/324 : comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/342 : comprising iridium
• CPC Class Codes: H10K 85/626 : containing more than one polycyclic condensed aromatic rings, e.g. bis-anthracene
• CPC Class Codes: H10K 85/631 : Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
• CPC Class Codes: H10K 85/633 : comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom
• CPC Class Codes: H10K 85/636 : comprising heteroaromatic hydrocarbons as substituents on the nitrogen atom
• CPC Class Codes: H10K 85/657 : Polycyclic condensed heteroaromatic hydrocarbons
• CPC Class Codes: H10K 85/6572 : comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole
• CPC Class Codes: Y10S 428/917 : Electroluminescent
• CPC Class Codes: Y10T 428/24942 : including components having same physical characteristic in differing degree

Abstract

An organic electroluminescence element comprising: an anode layer, a cathode layer, and an organic luminescence layer therebetween, the organic luminescence layer having a carbazole derivative with a glass-transition temperature of 110° C. or higher, and a phosphorescent dopant. This structure makes it possible to provide an organic electroluminescence element which can make use of the triplet exciton state of the carbazole derivative even at room temperature and which has a practical life and superior heat-resistance.

Claims

1. An organic electroluminescence element comprising:

an anode layer,

a cathode layer, and

an organic luminescence layer therebetween, the organic luminescence layer having a carbazole derivative with a glass-transition temperature of 110°

C. or higher, and a phosphorescent dopant.

2. The organic electroluminescence element according to claim 1, wherein the carbazole derivative is at least one of compounds represented by the following general formulae (1) to (4):

3. The organic electroluminescence element according to claim 1, wherein the carbazole derivative has at least two carbazole skeletons.

4. The organic electroluminescence element according to claim 1, wherein relationship of E1>

E2 is satisfied in which E1 represents triplet energy of the carbazole derivative and E2 represents triplet energy of the phosphorescent dopant.

5. The organic electroluminescence element according to claim 1, wherein triplet energy E1 of the carbazole derivative is a value of 21,000 cm⁻

1 or more.

6. The organic electroluminescence element according to claim 1, wherein the carbazole derivative has cyclic structure whose triplet energy is a value of 21,000 cm⁻

1 or more, and the cyclic structure contains an aromatic ring, a hetero ring, or combination thereof.

7. The organic electroluminescence element according to claim 1, wherein the phosphorescent dopant is a metal complex comprising at least one metal selected from the group consisting of Ir, Ru, Pd, Pt, Os and Re.

8. The organic electroluminescence element according to claim 7, wherein at least one ligand of the metal complex has at least one skeleton selected from the group consisting of phenylpyridine, bipyridyl and phenanthroline skeletons.

9. The organic electroluminescence element according to claim 1, wherein a blend amount of the phosphorescent dopant is 0.1 to 30 parts by weight per 100 parts of the carbazole derivative.

10. The organic electroluminescence element according to claim 1, wherein a hole barrier layer, an electron injection layer, or combination thereof is arranged between the anode layer and the cathode layer, and the hole barrier layer and the electron injection layer comprise an alkali metal.