Cyclooctatetraenes as electron transporters in organic light emitting diodes

• US 6,506,505 B1
• Filed: 08/16/1999
• Issued: 01/14/2003
• Est. Priority Date: 08/16/1999
• Status: Expired due to Fees

• Current Assignee: University of Southern California
• Original Assignee: University of Southern California
• Inventors: Hong, Haiping, Lu, Ping, Weber, William P., Thompson, Mark E.
• Primary Examiner(s): Yamnitzky, Marie
• Application Number:
  US09/375,125
• Time in Patent Office: 1,247 Days
• Field of Search: 428/690, 428/917, 313/504, 313/506
• US Class Current: 428/690
• 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 50/18 Carrier blocking layers
• CPC Class Codes: H10K 85/625 containing at least one aromatic ring having 7 or more carbon atoms, e.g. azulene
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

Organic light emitting devices the emissive layer comprises a host material containing a fluorescent or phosphorescent emissive molecule, which molecule is adapted to luminesce when a voltage is applied across the heterostructure, wherein the device comprises an electron transporting layer comprising a derivative of cyclooctatetraene.

Claims

1. An organic light emitting device comprising:

an anode;

a hole transporting layer;

an electron transporting layer comprising a substituted cyclooctatetraene,

wherein the substituted cyclooctatetraene is selected from the group consisting of a cyclooctatetraene molecule of the formula

wherein R₁ through R₈ are selected from the group consisting of aryl and arylalkynyl groups which may be further substituted, wherein there is a first group of four members of the set R₁ through R₈ that are identical and there is a second group consisting of the remaining four members of the set R₁ through R₈ that are identical, with the proviso that the members of the first group are different from the members of the second group and no three adjacent members of the set R₁ through R₈ are identical; and

a cathode.

2. The organic light emitting device of claim 1, used in a member of the group consisting of a larger display, a vehicle, a computer, a television, a printer, a large area wall, theater or stadium screen, a billboard and a sign.

3. The organic light emitting device of claim 1, further comprising:

a separate emissive layer comprising an emissive molecule, wherein the emissive molecule is selected from the group consisting of an emissive molecule and a combination of a host material and an emissive molecule, present as a dopant in said host material.

4. The organic light emitting device of claim 1, wherein the hole transporting layer comprises an emissive molecule wherein the emissive molecule is selected from the group consisting of an emissive molecule and a combination of a host material and an emissive molecule, present as a dopant in said host material.

5. The organic light emitting device of claim 1, wherein the electron transporting layer further comprises an emissive molecule wherein the emissive molecule is selected from the group consisting of an emissive molecule and a combination of a host material and an emissive molecule, present as a dopant in said host material.

6. The organic light emitting device of claim 1, wherein the substituted cyclooctatetraene is selected from the group consisting of a cyclooctatetraene molecule of the formula

7. The organic light emitting device of claim 6, wherein the substituted cyclooctatetraene has the following formula

8. The organic light emitting device of claim 6, wherein the substituted cyclooctatetraene has the following formula