Organic light-emitting device

Patent metadata

Field	Value
Publication number	US-10164193-B2
Application number	US-201515304293-A
Country	US
Kind code	B2
Filing date	Apr 16, 2015
Priority date	Apr 16, 2014
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

An organic light-emitting device comprising an anode ( 103 ); a cathode ( 109 ); a light-emitting layer ( 105 ) between the anode and the cathode; and an electron-transporting layer ( 107 ) comprising an electron-transporting material between the cathode and the light-emitting layer, wherein the cathode comprises a layer of a conducting material ( 109 B) and a layer of an alkali metal compound ( 109 A) between the electron-transporting layer and the layer of conducting material and wherein the electron-transporting material is a conjugated polymer comprising arylene repeat units.

First claim

The invention claimed is:

1. An organic light-emitting device comprising an anode; a cathode; a light-emitting layer between the anode and the cathode; and an electron-transporting layer comprising an electron-transporting material between the cathode and the light-emitting layer, wherein the cathode comprises a layer of a conducting material and a layer of an alkali metal compound between the electron-transporting layer and the layer of conducting material, wherein the electron-transporting material is a conjugated polymer comprising arylene repeat units, wherein the light-emitting layer comprises a host material and a light-emitting dopant, and wherein the host material has a LUMO level that is no more than 2.1 eV from vacuum level.

2. The organic light-emitting device according to claim 1 wherein the conjugated polymer has a LUMO level less than 2.36 eV from vacuum level.

3. The organic light-emitting device according to claim 1 wherein the conjugated polymer has a LUMO level no more than 2.3 eV from vacuum level.

4. The organic light-emitting device according to claim 1 wherein the conjugated polymer comprises fluorene repeat units.

5. The organic light-emitting device according to claim 4 wherein the conjugated polymer comprises repeat units of formula (VII):

wherein R 5 independently in each occurrence is a substituent.

6. The organic light-emitting device according to claim 5 wherein at least one R 5 is a group of formula —Ar-(PG) k wherein Ar is an aryl or heteroaryl group, PG is a polar group and k is at least 1.

7. The organic light-emitting device according to claim 1 wherein the host material is a partially conjugated polymer.

8. The organic light-emitting device according to claim 1 wherein the alkali metal compound is an alkali metal fluoride.

9. The organic light-emitting device according to claim 1 wherein the alkali metal compound is a sodium or potassium compound.

10. The organic light-emitting device according to claim 1 wherein the layer of conducting material is a metal.

11. The organic light-emitting device according to claim 10 wherein the metal is aluminium.

12. The organic light-emitting device according to claim 1 wherein cathode comprises a further layer of a conducting material.

13. The organic light-emitting device according to claim 12 wherein the further layer of conducting material is a layer of silver.

14. A method of forming an organic light-emitting device comprising an anode; a cathode; a light-emitting layer between the anode and the cathode; and an electron-transporting layer comprising an electron-transporting material between the cathode and the light-emitting layer, wherein the cathode comprises a layer of a conducting material and a layer of an alkali metal compound between the electron-transporting layer and the layer of conducting material and wherein the electron-transporting material is a conjugated polymer comprising arylene repeat units, wherein the light-emitting layer comprises a host material and a light-emitting dopant, and wherein the host material has a LUMO level that is no more than 2.1 eV from vacuum level, the method comprising the step of forming the electron-transporting layer by a solution deposition method using a solvent that does not dissolve the light-emitting layer.

15. The method according to claim 14 wherein the solvent is a polar solvent.

16. The method according to claim 15 wherein the light-emitting layer is deposited by a solution deposition method using a non-polar solvent.

17. An organic light-emitting device comprising an anode; a cathode; a light-emitting layer between the anode and the cathode; and an electron-transporting layer comprising an electron-transporting material between the cathode and the light-emitting layer, wherein the cathode comprises a layer of a conducting material and a layer of an alkali metal compound between the electron-transporting layer and the layer of conducting material, wherein the electron-transporting material has a LUMO level no more than 2.3 eV from vacuum level; wherein the light-emitting layer comprises a host material and a light-emitting dopant, and wherein the host material has a LUMO level that is no more than 2.1 eV from vacuum level.

Assignees

• Cambridge Display Tech Ltd
• Sumitomo Chemical Co

Inventors

• Kugler Thomas

Classifications

• C08G61/121

  derived from organic halides · CPC title

• H10K85/151

  Copolymers · CPC title

• H10K71/15

  characterised by the solvent used · CPC title

• H10K50/82

  Cathodes · CPC title

• H10K50/826

  Multilayers, e.g. opaque multilayers · CPC title