Stability OLED materials and devices

• US 7,902,374 B2
• Filed: 11/03/2006
• Issued: 03/08/2011
• Est. Priority Date: 05/06/2005
• Status: Active Grant

• Current Assignee: Universal Display Corporation
• Original Assignee: Universal Display Corporation
• Inventors: Deng, Jun, Mackenzie, Peter B., Tsai, Jui-Yi, Walters, Robert W., Brown, Cory S., Lin, Chun
• Primary Examiner(s): YAMNITZKY, MARIE ROSE
• Application Number:
  US11/592,275
• Publication Number:
  US 20070088167A1
• Time in Patent Office: 1,586 Days
• Field of Search: None
• US Class Current: 548/103
• CPC Class Codes: C07F 15/0033 Iridium compounds
• 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 2211/1029 containing one nitrogen atom as the heteroatom
• CPC Class Codes: C09K 2211/1044 containing two nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1059 containing three nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/1074 containing more than three nitrogen atoms as heteroatoms
• CPC Class Codes: C09K 2211/185 of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/18 Carrier blocking layers
• CPC Class Codes: H10K 85/324 comprising aluminium, e.g. Alq3
• CPC Class Codes: H10K 85/342 comprising iridium
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

Organic light emitting materials and devices comprising phosphorescent metal complexes comprising ligands comprising aryl or heteroaryl groups substituted at both ortho positions are described. An organic light emitting device, comprising: an anode; a hole transport layer; an organic emissive layer comprising an emissive layer host and an emissive dopant; an electron impeding layer; an electron transport layer; and a cathode disposed, in that order, over a substrate.

Claims

1. A phosphorescent compound, wherein the phosphorescent compound is a neutral metal complex of a bidentate, tridentate, tetradentate, pentadentate, or hexadentate ligand;

wherein the ligand comprises at least one first imidazole ring directly bonded to the metal;

wherein the first imidazole ring is substituted by a second aryl or heteroaryl ring that is not directly bonded to the metal, the second ring being substituted at both ortho positions by substituents independently selected from the group consisting of aryl or heteroaryl groups;

wherein the metal complex is an organometallic complex; and

wherein the metal is selected from the group consisting of the non-radioactive metals with atomic numbers greater than 40.

2. The compound according to claim 1, wherein the metal is selected from the group consisting of Re, Ru, Os, Rh, Ir, Pd, Pt, and Au.

3. The compound according to claim 2, wherein the metal is selected from the group consisting of Os, Ir, and Pt.

4. The compound according to claim 3, wherein the metal is Ir.

5. The compound according to claim 1, wherein the second ring is further substituted by one or more aryl, heteroaryl, or electron withdrawing groups.

6. The compound according to claim 5, wherein the second ring is substituted by a triphenylene group.

7. The compound according to claim 5, wherein the second ring is substituted by a group that comprises a carbazole.

8. The compound according to claim 1, wherein the substituents at the ortho positions of the second ring are diarylaminoaryl groups.

9. The compound according to claim 1, which has a highest energy peak in a phosphorescence emission spectrum at a wavelength less than about 480 nm.

10. The compound according to claim 1, which is a homoleptic compound.

11. The compound according to claim 1, which is a heteroleptic compound.

12. The compound according to claim 1, which is a sublimable compound.

13. The compound according to claim 1, wherein the second ring is attached to a nitrogen atom of the first ring.

14. The compound according to claim 1, wherein the compound is selected from:

15. The compound according to claim 1, wherein the compound is selected from:

16. The compound according to claim 1, wherein the compound is:

17. The compound according to claim 1, wherein the second ring is a benzene ring having a para position, and wherein the second ring is further substituted by an aryl group at the para position on the second ring.

18. The compound according to claim 17, wherein the first imidazole ring is further substituted by a third ring, the third ring being an aryl or heteroaryl ring directly bonded to the metal.

19. The compound according to claim 18, wherein the ortho position substitutions do not form a fused ring with the second ring.

20. The compound according to claim 1, wherein the first imidazole ring is further substituted by a third ring, the third ring being an optionally substituted benzene ring directly bonded to the metal.

21. The compound according to claim 20, wherein the ortho position substitutions do not form a fused ring with the second ring.