Organic electroluminescent element

Patent metadata

Field	Value
Publication number	US-10186665-B2
Application number	US-201314758118-A
Country	US
Kind code	B2
Filing date	Dec 27, 2013
Priority date	Dec 28, 2012
Publication date	Jan 22, 2019
Grant date	Jan 22, 2019

Abstract

An organic electroluminescence device includes an anode, a cathode and an emitting layer, in which the emitting layer includes a first compound and a second compound and each of the first compound and the second compound is a compound emitting thermally activated delayed fluorescence.

First claim

The invention claimed is:

1. An organic electroluminescence device, comprising:
an anode;
a cathode; and
an emitting layer, wherein
the emitting layer comprises a first compound and a second compound,
each of the first compound and the second compound is a compound emitting thermally activated delayed fluorescence,
a difference between singlet energy EgS(M1) of the first compound and energy gap Eg 77K (M1) at 77K of the first compound is 0.3 eV or less, and
a difference between singlet energy EgS(M2) of the second compound and energy gap Eg 77K (M2) at 77K of the second compound is 0.3 eV or less.

2. The organic electroluminescence device according to claim 1 , wherein
a difference between the singlet energy EgS(M1) of the first compound and the singlet energy EgS(M2) of the second compound is 0.2 eV or less.

3. The organic electroluminescence device according to claim 1 , wherein
a difference between the energy gap Eg 77K (M1) at 77K of the first compound and the energy gap Eg 77K (M2) at 77K of the second compound is 0.2 eV or less.

4. The organic electroluminescence device according to claim 1 , wherein
at least one of the first compound and the second compound has a main peak wavelength of 500 nm or less.

5. The organic electroluminescence device according to claim 1 , wherein
at least one of the first compound and the second compound has a main peak wavelength of 480 nm or less.

6. The organic electroluminescence device according to claim 1 , wherein
the first compound has a concentration of 20 mass % or more in the emitting layer, and
the second compound has a concentration of 20 mass % or more in the emitting layer.

7. The organic electroluminescence device according to claim 1 , wherein
the emitting layer further comprises a third compound, and
the third compound is a compound emitting thermally activated delayed fluorescence.

8. The organic electroluminescence device according to claim 7 , wherein
a difference between singlet energy EgS(M3) of the third compound and energy gap Eg 77K (M3) at 77K of the third compound is 0.3 eV or less.

9. The organic electroluminescence device according to claim 7 , wherein
the third compound has a concentration of 20 mass % or more in the emitting layer.

10. The organic electroluminescence device according to claim 7 , wherein
a difference between the singlet energy EgS(M1) of the first compound and the singlet energy EgS(M3) of the third compound is 0.2 eV or less, and
a difference between the singlet energy EgS(M2) of the second compound and the singlet energy EgS(M3) of the third compound is 0.2 eV or less.

11. The organic electroluminescence device according to claim 7 , wherein
a difference between the energy gap Eg 77K (M1) at 77K of the first compound and the energy gap Eg 77K (M3) at 77K of the third compound is 0.2 eV or less, and
a difference between the energy gap Eg 77K (M2) at 77K of the second compound and the energy gap Eg 77K (M3) at 77K of the third compound is 0.2 eV or less.

12. The organic electroluminescence device according to claim 1 , wherein
the emitting layer does not comprise a metal complex.

13. An electronic device comprising the organic electroluminescence device according to claim 1 .

14. The organic electroluminescence device according to claim 1 , wherein
a difference between singlet energy EgS(M1) of the first compound and energy gap Eg 77K (M1) at 77K of the first compound is less than 0.3 eV, and
a difference between singlet energy EgS(M2) of the second compound and energy gap Eg 77K (M2) at 77K of the second compound is less than 0.3 eV.

15. The organic electroluminescence device according to claim 14 , wherein
a difference between singlet energy EgS and energy gap Eg 77K at 77K of one of the first compound and the second compound is less than 0.2 eV.

16. The organic electroluminescence device according to claim 1 , wherein
a difference between singlet energy EgS(M1) of the first compound and energy gap Eg 77K (M1) at 77K of the first compound is less than 0.2 eV, and
a difference between singlet energy EgS(M2) of the second compound and energy gap Eg 77K (M2) at 77K of the second compound is less than 0.2 eV.

17. The organic electroluminescence device according to claim 7 , wherein
a difference between singlet energy EgS(M1) of the first compound and energy gap Eg 77K (M1) at 77K of the first compound is less than 0.3 eV,
a difference between singlet energy EgS(M2) of the second compound and energy gap Eg 77K (M2) at 77K of the second compound is less than 0.3 eV, and
a difference between singlet energy EgS(M3) of the third compound and energy gap Eg 77K (M3) at 77K of the third compound is less than 0.3 eV.

18. The organic electroluminescence device according to claim 17 , wherein
a difference between singlet energy EgS and energy gap Eg 77K at 77K of one of the first, second and third compound is less than 0.2 eV.

19. The organic electroluminescence device according to claim 17 , wherein
a difference between singlet energy EgS and energy gap Eg 77K at 77K of two of the first, second and third compound is less than 0.2 eV.

20. The organic electroluminescence device according to claim 7 , wherein
a difference between singlet energy EgS(M1) of the first compound and energy gap Eg 77K (M1) at 77K of the first compound is less than 0.2 eV,
a difference between singlet energy EgS(M2) of the second compound and energy gap Eg 77K (M2) at 77K of the second compound is less than 0.2 eV, and
a difference between singlet energy EgS(M3) of the third compound and energy gap Eg 77K (M3) at 77K of the third compound is less than 0.2 eV.

21. The organic electroluminescence device according to claim 1 , wherein the emitting layer further comprises a third compound.

22. The organic electroluminescence device according to claim 21 , wherein the third compound is a dopant.

23. The organic electroluminescence device according to claim 21 , wherein the third compound does not emit thermally activated delayed fluorescence.

24. The organic electroluminescence device according to claim 2 , wherein the emitting layer further comprises a third compound.

25. The organic electroluminescence device according to claim 24 , wherein the third compound is a dopant.

26. The organic electroluminescence device according to claim 24 , wherein the third compound does not emit thermally activated delayed fluorescence.

27. The organic electroluminescence device according to claim 12 , wherein the emitting layer further comprises a third compound.

28. The organic electroluminescence device according to claim 27 , wherein the third compound is a dopant.

29. The organic electroluminescence device according to claim 27 , wherein the third compound does not emit thermally activated delayed fluorescence.

30. The organic electroluminescence device according to claim 22 , wherein the third compound is a fluorescent dopant.

31. The organic electroluminescence device according to claim 25 , wherein the third compound is a fluorescent dopant.

32. The organic electroluminescence device according to claim 28 , wherein the third compound is a fluorescent dopant.

Assignees

• Idemitsu Kosan Co

Inventors

• Kawamura Masahiro
• Mizuki Yumiko
• Ogiwara Toshinari
• Kuma Hitoshi

Classifications

• C09K2211/1044

  containing two nitrogen atoms as heteroatoms · CPC title

• C09K2211/1092

  containing sulfur as the only heteroatom · CPC title

• H01L51/5012

  Electricity · mapped topic

• H01L51/0094

  Electricity · mapped topic

• H01L51/0071

  Electricity · mapped topic