Organic light emitting materials and devices

• US 20040086742A1
• Filed: 11/06/2002
• Published: 05/06/2004
• Est. Priority Date: 11/06/2002
• Status: Active Grant

• Current Assignee: Universal Display Corporation
• Original Assignee: University of Southern California
• Inventors: knowles, David B., Ma, Bin, Thompson, Mark E., Walters, Robert W., Kwong, Raymond, Tung, Yeh-Jiun, Djurovich, Peter I.
• Granted Patent: US 6,916,554 B2
• Time in Patent Office: Days
• US Class Current: 428/690
• CPC Class Codes: C07F 15/004 without a metal-carbon linkage
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: C09K 2211/1022 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: C09K 2211/1029 containing one nitrogen atom as the heteroatom
• CPC Class Codes: C09K 2211/185 of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd
• CPC Class Codes: H10K 85/342 comprising iridium
• CPC Class Codes: Y10S 428/917 Electroluminescent

Abstract

An organic light emitting device is provided. The device has an anode, a cathode, and an emissive layer disposed between the anode and the cathode. The emissive layer further comprising an emissive material having the structure:

M may be a metal having an atomic weight greater than 40. R₃ may be a substituent having a Hammett value less than about −0.17, between about −0.15 and 0.05, or greater than about 0.07. R₅ may be H or any substituent. A may be a 5 or 6 member heteroaryl ring system. “m” may be at least 1. “n” may be at least zero. (X—Y) may be an ancillary ligand. The emissive material itself is also provided. The emissive material may have improved stability, and may provide a saturated blue emission.

Claims

1. An emissive material having the structure:

2. The emissive material of claim 1, wherein the emissive material has the structure:

3. The emissive material of claim 2, wherein n is zero and m is the maximum number of bidentate ligands that may be attached to the metal M.

4. The emissive material of claim 2, wherein M is selected from the group consisting of Ir, Pt, Pd, Rh, Re, Ru, Os, Tl, Pb, Bi, In, Sn, Sb, Te, Au, and Ag.

5. The emissive material of claim 4, wherein M is Ir.

6. The emissive material of claim 4, wherein M is Pt.

7. The emissive material of claim 2, wherein n is zero.

8. The emissive material of claim 5, wherein R₃ is selected from the group consisting of:

alkyl, alkoxy, amino, carboxy, cyano, aryls, and 5 and 6 member heteroaryls.

9. The emissive material of claim 1, wherein A is a substituted heteroaryl ring system.

10. The emissive material of claim 5, wherein R₃ is an electron donating group having a Hammett number less than about −

0.17.

11. The emissive material of claim 5, wherein R₃ is an electron withdrawing group having a Hammett number greater than about 0.07.

12. The emissive material of claim 5, wherein R₃ has a Hammett number between about −

0.15 and 0.05.

13. The emissive material of claim 5, wherein the emissive material has a photoluminescent L₁₀₀/L₀ stability of at least 82%.

14. The emissive material of claim 13, wherein the emissive material has a photoluminescent L₁₀₀/L₀ stability of at least 91%.

15. The emissive material of claim 13, wherein the emissive material in a non-polar solvent has CIE coordinates within a radius of 0.25 from saturated blue.

16. The emissive material of claim 13, wherein the emissive material in a non-polar solvent has CIE coordinates within a radius of 0.125 from saturated blue.

17. The emissive material of claim 13, wherein the emissive material in a non-polar solvent emits a spectrum having a peak wavelength of 452 nm or less.

18. The emissive material of claim 5, wherein at least one of R₅ and R′

is selected from the group consisting of electron withdrawing groups and electron donating groups.

19. The emissive material of claim 1, wherein the material is incorporated into a polymer.

20. The emissive material of claim 1, wherein the material is incorporated into a dendrimer

21. The emissive material of claim 1, wherein R₃ is a phenyl group.

22. The emissive material of claim 21, wherein R₃ is an unsubstituted phenyl group.

23. The emissive material of claim 2, wherein the emissive material has the structure:

24. The emissive material of claim 23, wherein R₅ and R′

are unsubstituted.

25. The emissive material of claim 1, wherein R₃ includes a cyano group.

26. The emissive material of claim 5, wherein m is 3, n is zero, R₃ is a cyano group, and R′

and R₅ are unsubstituted.

50. The emissive material of claim 1, wherein R₃ includes an atom connected to the phenyl ring having a non-empty p-orbital or n-orbital that is in π

-conjugation or partial π

-conjugation with the π

-system in the phenyl ring.

27. An emissive material having the structure:

28. An emissive material comprising a ligand having the structure:

29. An emissive material comprising a ligand having the structure:

30. The emissive material of claim 29, wherein R₃ is an electron donating group having a Hammett number less than about −

0.17.

31. The emissive material of claim 29, wherein R₃ is an electron withdrawing group having a Hammett number greater than about 0.07.

32. The emissive material of claim 29, wherein R₃ has a Hammett number between about 0.15 and 0.05.

33. An organic light emitting device, comprising:

(a) an anode;

(b) a cathode; and

(c) an emissive layer disposed between the anode and the cathode, the emissive layer further comprising an emissive material having the structure;

wherein;

M is a metal having an atomic weight greater than 40;

R₃ is a substituent having a Hammett value less than about −

0.17, between about −

0.15 and 0.05, or greater than about 0.07;

R₅ is H or any substituent;

A is a 5 or 6 member heteroaryl ring system;

m is at least 1;

n is at least zero;

(X—

Y) is an ancillary ligand.

34. The device of claim 33, wherein R₃ is an electron donating group having a Hammett number less than about −

0.17.

35. The device of claim 33, wherein R₃ is an electron withdrawing group having a Hammett number greater than about 0.07.

36. The device of claim 33, wherein R₃ has a Hammett number between about −

0.15 and 0.05.

37. The device of claim 33, wherein the emissive material has the structure:

38. The device of claim 33, wherein R₃ is a phenyl group.

39. The device of claim 38, wherein R₃ is an unsubstituted phenyl group.

40. The device of claim 37, wherein the emissive material has the structure:

41. The device of claim 40, wherein R₅ and R′

are unsubstituted.

42. The device of claim 33, wherein R₃ includes a cyano group.

43. The device of claim 33, wherein the emissive material has the structure:

The emissive material of claim 5, wherein m is 3, n is zero, R₃ is a cyano group, and R1 and R₅ are unsubstituted.

44. An organic light emitting device, comprising:

(a) an anode;

(b) a cathode; and

(c) an emissive layer disposed between the anode and the cathode, the emissive layer further comprising an emissive material having the structure;

wherein;

M is a metal having an atomic weight greater than 40;

R₃ is a substituent other than —

CH₃ and —

F;

R₅ is H or any substituent;

A is a 5 or 6 member heteroaryl ring system;

m is at least 1;

n is at least zero;

(X—

Y) is an ancillary ligand.

45. An organic light emitting device, comprising:

(a) an anode;

(b) a cathode; and

(c) an emissive layer disposed between the anode and the cathode, the emissive layer further comprising an emissive material having the structure;

wherein;

the ligand is attached to a metal having an atomic weight greater than 40;

R₃ is a substituent other than —

CH₃ and —

F;

R₅ is H or any substituent; and

wherein R′

is selected from the group consisting of H and any substituent, including mono-, di-, tri-, and tetra-substitution.

46. An organic light emitting device, comprising:

(a) an anode;

(b) a cathode; and

(c) an emissive layer disposed between the anode and the cathode, the emissive layer further comprising an emissive material having the structure;

wherein;

the ligand is attached to a metal having an atomic weight greater than 40;

R₃ is a substituent having a Hammett value less than about −

0.17, between about −

0.15 and 0.05, or greater than about 0.07;

R₅ is H or any substituent; and

wherein R′

is selected from the group consisting of H and any substituent, including mono-, di-, tri-, and tetra-substitution.

47. The device of claim 46, wherein R₃ is an electron donating group having a Hammett number less than about −

0.17.

48. The device of claim 47, wherein R₃ is an electron withdrawing group having a Hammett number greater than about 0.07.

49. The device of claim 48, wherein R₃ has a Hammett number between about −

0.15 and 0.05.