Light-emitting element, light-emitting device, electronic device, and lighting device

Patent metadata

Field	Value
Publication number	US-10897012-B2
Application number	US-201816182689-A
Country	US
Kind code	B2
Filing date	Nov 7, 2018
Priority date	Aug 3, 2012
Publication date	Jan 19, 2021
Grant date	Jan 19, 2021

Abstract

A light-emitting element having a long lifetime is provided. A light-emitting element exhibiting high emission efficiency in a high luminance region is provided. A light-emitting element includes a light-emitting layer between a pair of electrodes. The light-emitting layer contains a first organic compound, a second organic compound, and a phosphorescent compound. The first organic compound is represented by a general formula (G0). The molecular weight of the first organic compound is greater than or equal to 500 and less than or equal to 2000. The second organic compound is a compound having an electron-transport property. In the general formula (G0), Ar1 and Ar2 each independently represent a fluorenyl group, a spirofluorenyl group, or a biphenyl group, and Ar3 represents a substituent including a carbazole skeleton.

First claim

The invention claimed is:

1. A light-emitting device comprising:
an anode;
a cathode;
a light-emitting layer comprising two kinds of organic compounds which are configured to form an exciplex; and
a compound,
wherein the light-emitting layer is between the anode and the cathode,
wherein the compound is between the anode and the light-emitting layer and represented by General Formula (G0):

wherein each of Ar 1 and Ar 2 independently represents a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted spirofluorenyl group, or a substituted or unsubstituted biphenyl group, and
wherein Ar 3 represents a substituent including a carbazole skeleton.

2. The light-emitting device according to claim 1 ,
wherein a layer comprising the compound represented by General Formula (G0) is in contact with the light-emitting layer.

3. The light-emitting device according to claim 1 ,
wherein a molecular weight of the compound represented by General Formula (G0) is greater than or equal to 500 and less than or equal to 2000.

4. A light-emitting device comprising:
an anode;
a cathode;
a light-emitting layer comprising two kinds of organic compounds which are configured to form an exciplex;
a region comprising an acceptor substance; and
a compound,
wherein the light-emitting layer is between the anode and the cathode,
wherein the region comprising the acceptor substance is between the anode and the light-emitting layer,
wherein the compound is between the light-emitting layer and the region comprising the acceptor substance and represented by General Formula (G0):

wherein each of Ar 1 and Ar 2 independently represents a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted spirofluorenyl group, or a substituted or unsubstituted biphenyl group, and
wherein Ar 3 represents a substituent including a carbazole skeleton.

5. The light-emitting device according to claim 4 ,
wherein the region comprising the acceptor substance is a region comprising a substance having a high hole-transport property and the acceptor substance.

6. The light-emitting device according to claim 5 ,
wherein a mass ratio of the acceptor substance to the substance having a high hole-transport property in the region comprising the acceptor substance is 0.1:1 to 4.0:1.

7. The light-emitting device according to claim 5 ,
wherein the substance having a high hole-transport property is an organic compound having a hole mobility of 10 −6 cm 2 /Vs or more.

8. The light-emitting device according to claim 4 ,
wherein in the region comprising the acceptor substance, a layer comprising a substance having a high hole-transport property and a layer comprising the acceptor substance are stacked.

9. The light-emitting device according to claim 8 ,
wherein a mass ratio of the acceptor substance to the substance having a high hole-transport property in the region comprising the acceptor substance is 0.1:1 to 4.0:1.

10. The light-emitting device according to claim 8 ,
wherein the substance having a high hole-transport property is an organic compound having a hole mobility of 10 −6 cm 2 /Vs or more.

11. The light-emitting device according to claim 4 ,
wherein the region comprising the acceptor substance is in contact with the anode.

12. The light-emitting device according to claim 4 ,
wherein a molecular weight of the compound represented by General Formula (G0) is greater than or equal to 500 and less than or equal to 2000.

13. A light-emitting device comprising:
an anode;
a cathode;
a light-emitting layer comprising three kinds of compounds;
a region comprising an acceptor substance; and
a compound,
wherein the light-emitting layer is between the anode and the cathode,
wherein the region comprising the acceptor substance is positioned between the anode and the light-emitting layer,
wherein the compound is between the light-emitting layer and the region comprising the acceptor substance and represented by General Formula (G0):

wherein each of Ar 1 and Ar 2 independently represents a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted spirofluorenyl group, or a substituted or unsubstituted biphenyl group, and
wherein Ar 3 represents a substituent including a carbazole skeleton.

14. The light-emitting device according to claim 13 ,
wherein the region comprising the acceptor substance is a region comprising a substance having a high hole-transport property and the acceptor substance.

15. The light-emitting device according to claim 14 ,
wherein a mass ratio of the acceptor substance to the substance having a high hole-transport property in the region comprising the acceptor substance is 0.1:1 to 4.0:1.

16. The light-emitting device according to claim 14 ,
wherein the substance having a high hole-transport property is an organic compound having a hole mobility of 10 −6 cm 2 /Vs or more.

17. The light-emitting device according to claim 13 ,
wherein in the region comprising the acceptor substance, a layer comprising a substance having a high hole-transport property and a layer comprising the acceptor substance are stacked.

18. The light-emitting device according to claim 17 ,
wherein a mass ratio of the acceptor substance to the substance having a high hole-transport property in the region comprising the acceptor substance is 0.1:1 to 4.0:1.

19. The light-emitting device according to claim 17 ,
wherein the substance having a high hole-transport property is an organic compound having a hole mobility of 10 −6 cm 2 /Vs or more.

20. The light-emitting device according to claim 13 ,
wherein the region comprising the acceptor substance is in contact with the anode.

21. The light-emitting device according to claim 13 ,
wherein a molecular weight of the compound represented by General Formula (G0) is greater than or equal to 500 and less than or equal to 2000.

22. A light-emitting device comprising:
an anode;
a cathode;
a light-emitting layer comprising two kinds of organic compounds which are configured to form an exciplex and a phosphorescent compound;
a region comprising an acceptor substance; and
a compound,
wherein a difference between an energy value of an emission of the exciplex and an energy of a peak of an absorption band having the lowest wavelength in an absorption spectrum of the phosphorescent compound is 0.2 eV or less,
wherein the light-emitting layer is between the anode and the cathode,
wherein the region comprising the acceptor substance is between the anode and the light-emitting layer,
wherein the compound is between the light-emitting layer and the region comprising the acceptor substance and represented by General Formula (G0):

wherein each of Ar 1 and Ar 2 independently represents a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted spirofluorenyl group, or a substituted or unsubstituted biphenyl group, and
wherein Ar 3 represents a substituent including a carbazol

Assignees

• Semiconductor Energy Lab

Inventors

• Hamada Takao
• Seo Hiromi
• Abe Kanta
• Takeda Kyoko
• Seo Satoshi

Classifications

• C09K2211/1007

  Non-condensed systems · CPC title

• C09K2211/185

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

• H10K85/342

  comprising iridium · CPC title

• H10K85/633 Primary

  comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom · CPC title

• H10K85/631 Primary

  Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine · CPC title