Organic light-emitting device

Patent metadata

Field	Value
Publication number	US-11024818-B2
Application number	US-201515532891-A
Country	US
Kind code	B2
Filing date	Dec 1, 2015
Priority date	Dec 2, 2014
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

Organic Light-Emitting Device An organic light-emitting device (100) comprising an anode (103); a cathode (109); a light-emitting layer (107) between the anode and the cathode; and a hole-transporting layer (105) between the anode and the cathode, wherein the light-emitting layer comprises a light-emitting compound of formula (I) and the hole-transporting layer comprises a hole-transporting material having a HOMO level that is no more than 5.1 e V from vacuum level: N N ML x R 2 (R) m (R) n y (I) wherein: R in each occurrence is independently a substituent; R 2 is H or a substituent; m is 0, 1 or 2; n is 0, 1, 2, 3 or 4; M is a transition metal; L is a ligand; y is at least 1; and x is 0 or a positive integer.

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 a hole-transporting layer between the anode and the light-emitting layer and adjacent to the light-emitting layer, wherein the light-emitting layer comprises a light-emitting compound of formula (I) and the hole-transporting layer comprises a hole-transporting material having a HOMO level that is no more than 5.1 eV from vacuum level as measured by square wave voltammetry, and the HOMO level of the compound of formula (I) is closer to vacuum level than the HOMO level of the hole-transporting material as measured by square wave voltammetry:

wherein:
R 1 in each occurrence is independently a substituent;
R 2 is H or a substituent;
m is 0, 1 or 2;
n is 0, 1, 2, 3 or 4;
M is a transition metal;
L is a ligand;
y is at least 1; and
x is 0 or a positive integer;
and wherein the hole-transporting material is a non-polymeric compound of formula (III) or a polymer comprising a repeat unit of formula (III-2):

wherein:
Ar 8 , Ar g , Ar 10 , Ar 11 and Ar 12 in each occurrence are independently fluorene or phenyl, each of which is independently unsubstituted or substituted with one or more substituents selected from C 1-20 alkyl, wherein one or more non-adjacent C atoms may be replaced with optionally substituted aryl or heteroaryl, O, S, C═O or —COO— and one or more H atoms may be replaced with F; and a crosslinkable group;
R 3 , R 4 , R 5 and R 6 are each independently:
an aryl or heteroaryl group Ar 13 or a branched or linear chain of Ar 13 groups, wherein each Ar 13 independently is unsubstituted or substituted with one or more substituents R 18 selected from C 1-20 alkyl wherein one or more non-adjacent C atoms may be replaced with optionally substituted aryl or heteroaryl, O, S, C═O, or —COO—, and one or more H atoms may be replaced with F;
a C 1-20 alkyl group, wherein one or more non-adjacent C atoms of the C 1-20 alkyl group may be replaced with O, S, —C(═O)—, or —C(═O)O—, and one or more H atoms of the C 1-20 alkyl group may be replaced with F;
a C 1-20 alkyl-phenyl group, wherein one or more non-adjacent C atoms of the C 1-20 alkyl group may be replaced with O, S, —C(═O)—, or —C(═O)O—, and one or more H atoms of the C 1-20 alkyl group may be replaced with F; or
a crosslinkable unit that is bound directly to the N atom of formula (III) or (III-2) or spaced apart therefrom by a spacer group;
wherein Ar 9 and Ar 10 are linked by a group of formula CR 19 2 wherein each occurrence of R 19 in the group linking Ar 9 and Ar 10 is independently a substituent; and
p is 0 or a positive integer.

2. An organic light-emitting device according to claim 1 wherein the hole-transporting material has a HOMO level that is no more than 5.0 eV from vacuum level as measured by square wave voltammetry.

3. An organic light-emitting device according to claim 1 wherein the light-emitting compound of formula (I) has a photoluminescent spectrum with a peak of up to about 490 nm.

4. An organic light-emitting device according to claim 1 wherein the hole-transporting layer comprises a light-emitting material.

5. An organic light-emitting device according to claim 4 wherein the light-emitting material of the hole-transporting layer has a photoluminescence spectrum with a peak in the range of about more than 550 up to about 700 nm.

6. An organic light-emitting device according to claim 1 wherein the device is a white light-emitting device.

7. An organic light-emitting device according to claim 1 wherein y is 3 and x is 0.

8. An organic light-emitting device according to claim 1 wherein R 2 is a C 1-30 hydrocarbyl group.

9. An organic light-emitting device according to claim 1 wherein n is 0.

10. An organic light-emitting device according to claim 1 wherein m is 0.

11. An organic light-emitting device according to claim 1 wherein the HOMO level of the compound of formula (I) is no more than 0.1 eV closer to vacuum level than the HOMO level of the hole-transporting material as measured by square wave voltammetry.

12. An organic light-emitting device according to claim 1 , wherein the hole-transporting material is the polymer comprising a repeat unit of formula (III-2).

13. An organic light-emitting device according to claim 1 , wherein R 3 , R 4 , R 5 , and R 6 are each independently an aryl or heteroaryl group Ar 13 which is unsubstituted or substituted with one or more substituents R 18 .

14. An organic light-emitting device according to claim 1 wherein the hole-transporting layer is adjacent to and in contact with the light-emitting layer.

15. A method of forming an organic light-emitting device according to claim 1 comprising the steps of forming the hole-transporting layer over the anode; forming the light-emitting layer over the hole-transporting layer; and forming the cathode over the first light-emitting layer.

16. A method according to claim 15 wherein the first light-emitting layer is formed by depositing a formulation comprising the compound of formula (I) over the hole-transporting layer, and evaporating the one or more solvents.

17. A method according to claim 16 wherein the hole-transporting layer is crosslinked prior to formation of the light-emitting layer.

18. An organic light-emitting device comprising an anode; a cathode; a light-emitting layer between the anode and the cathode; and a hole-transporting layer between the anode and the light-emitting layer and adjacent to the light-emitting layer, wherein the light-emitting layer comprises a light-emitting compound of formula (I) and the hole-transporting layer comprises a hole-transporting material having a HOMO level that is no more than 5.0 eV from vacuum level as measured by square wave voltammetry:

wherein:
R 1 in each occurrence is independently a substituent;
R 2 is H or a substituent;
m is 0, 1 or 2
n is 0, 1, 2, 3 or 4;
M is a transition metal;
L is a ligand;
y is at least 1; and
x is 0 or a positive integer;
and wherein the hole-transporting material is a non-polymeric compound of formula (III) or
a polymer comprising a repeat unit of formula (III-2):

wherein:
Ar 8 , Ar g , Ar 10 , Ar 11 and Ar 12 in each occurrence are independently fluorene or phenyl, each of which is independently unsubstituted or substituted with one or more substituents selected from C 1-20 alkyl, wherein one or more non-adjacent C atoms may be replaced with optionally substituted aryl or heteroaryl, O, S, C═O or —COO— and one or more H atoms may be replaced with F; and a crosslinkable group;
R 3 , R 4 , R 5 and R 6 are each independently:
an aryl or heteroaryl group Ar 13 or a branched or linear chain of Ar 13 groups, wherein each Ar 13 independently is unsubstituted or substituted with one or more substituents R 18 selected from C 1-20 alkyl wherein one or more non-adjacent C atoms may be replaced with optionally substituted aryl or heteroa

Assignees

• Cambridge Display Tech Ltd
• Sumitomo Chemical Co

Inventors

• King Simon
• Mohamad David

Classifications

• H10K2101/40 Primary

  Interrelation of parameters between multiple constituent active layers or sublayers, e.g. HOMO values in adjacent layers · CPC title

• C07D233/54

  having two double bonds between ring members or between ring members and non-ring members · CPC title

• C09K11/06 Primary

  containing organic luminescent materials · CPC title

• C09K2211/185

  of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd · CPC title

• C09K2211/1044

  containing two nitrogen atoms as heteroatoms · CPC title