Organic element for electroluminescent devices
View Patent ↗Disclosed is an OLED device comprising a light-emitting layer containing a light emitting bis(azinyl)methene boron complex compound comprising a complex system of at least five fused rings and bearing, on at least one ring carbon or nitrogen, a substituent sufficient to provide a wavelength of maximum emission of less than 520 nm as measured at a concentration of <10 −3 M in ethyl acetate solvent.
1. An OLED device comprising a light-emitting layer containing a light emitting bis(azinyl)methene boron complex compound represented by Formula (1):
wherein
A and A′ represent independent azine ring group systems corresponding to 6-membered aromatic ring systems containing at least one nitrogen;
each X a and X b is an independently selected substituent, two of which may join to form a fused ring to A or A′ which may include further fused ring substitution;
m and n are independently 0 to 4;
Y is H or a substituent:
Z a and Z b are independently selected substituents;
wherein
either (1) at least one of X a and X b is selected from the group consisting of fluoro and alkyl, alkoxy, sulfamoyl, amido , amino, and aryloxy groups or (2) Y is selected from the group consisting of cyano, trifluoromethyl, fluoro, alkylsulfonyl, nitro, and sulfonamido groups or (3) both (1) and (2) are satisfied;
provided that 1, 2, 3, 4, 1′, 2′, 3′, and 4′ are independently selected as either carbon or nitrogen atoms;
and provided that the selection of each X a and X b , including further substitution, results in a fused ring system of at least 5 fused rings; and
provided further that there is at least one substituent on the fused ring system sufficient to provide a wavelength of maximum emission of less than 520 nm at a concentration of <10 −3 M in EtOAc.
2. The device of claim 1 wherein the bis(azinyl)methene boron complex compound is a polymer.
3. The device of claim 1 wherein the boron complex compound includes a bis(pyridinyl)methene boron complex group.
4. The device of claim 1 wherein the boron complex compound includes a bis(quinolinyl)methene boron complex group.
5. The device of claim 1 wherein the layer comprises a host and dopant where the dopant is present in an amount of up to 10 wt % of the host.
6. The device of claim 5 wherein the host comprises a chelated oxinoid compound or an anthracene compound.
7. The device of claim 6 wherein the host comprises a chelated oxinoid compound.
8. The device of claim 7 wherein the host comprises tris(8-quinolinolato)aluminum (III).
9. The device of claim 6 wherein the host comprises an anthracene compound.
10. The device of claim 9 wherein the host comprises a 9,10-di-(2-naphthyl)anthracene compound.
11. The device of claim 9 wherein the host comprises a 2-tert-butyl-9,10-di-(2-naphthyl)anthracene compound.
12. The device of claim 5 wherein the dopant is present in an amount of 0.1-5.0 wt % of the host.
13. The device of claim 1 wherein the substituents provide a reduced loss of initial luminance compared to the device containing no bis(azinyl)methane boron complex compound.
14. The device of claim 1 wherein 1, 2, 3, 4, 1′, 2′, 3′, and 4′ are all carbon atoms.
15. The device of claim 1 wherein at least one of ring A or A′ contains substituents joined to form a fused ring.
16. The device of claim 1 wherein both ring A and A′ contain substituents joined to form a fused ring.
17. The device of claim 1 wherein at least one of Z a and Z b are independently selected from the group consisting of fluoro and alkyl, aryl, alkoxy and aryloxy groups.
18. The device of claim 17 wherein at least one of Z a and Z b is F.
19. The device of claim 1 wherein the wavelength of maximum emission is less than 515 nm.
20. The device of claim 19 wherein the wavelength of maximum emission is less than 510 nm.
21. The device of claim 1 wherein the bis(azinyl)methane boron complex compound comprises a ring system of five or six fused rings.
22. The device of claim 1 wherein the bis(azinyl)methane boron complex compound comprises a ring system of five fused rings.
23. The device of claim 1 wherein Y is cyano.
24. The device of claim 1 wherein Y is trifluoromethyl.
25. The device of claim 1 wherein the boron complex compound is selected from the following:
26. The device of claim 1 wherein the boron compound is selected from the following:
27. A light emitting device containing the OLED device of claim 1 .
28. A method of emitting light comprising subjecting the device of claim 1 to an applied voltage.
29. The device of claim 1 wherein the light emitting layer comprises two hosts of at least 5 wt % of the layer of each, one being a chelated oxinoid, and the other an anthracene compound.
30. The device of claim 29 wherein the light emitting layer comprises two hosts of at least 5 wt % of the layer of each, one being represented by the formula:
wherein
M represents a metal;
n is an integer of from 1 to 4; and
Z independently in each occurrence represents the atoms completing a nucleus having at least two fused aromatic rings.
31. The device of claim 29 wherein the anthracene host is a 2-tert-butyl-9, 10-di-(2-naphthyl)anthracene (TBADN).
32. The device of claim 29 wherein the anthracene is present in an amount of greater than 50 wt % of the layer.
33. The device of claim 29 wherein the anthracene is present in an amount of greater than 75 wt % of the layer.