IP Library › Granted Patent US 12,550,604
Granted Patent B2
US 12,550,604 · App. 18/411,456 · Granted Feb 10, 2026

Organic electroluminescent materials and devices

Inventors: Chuanjun Xia (Lawrenceville, NJ); Raymond C. Kwong (Plainsboro, NJ); Suman Layek (Lawrenceville, NJ)
Assignee: UNIVERSAL DISPLAY CORPORATION
H10K85/342C07F15/0033C09K11/06H05B33/10C09K2211/1007C09K2211/1011C09K2211/1029C09K2211/1088C09K2211/1092C09K2211/185H10K50/11H10K2101/10
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Quick Facts
Patent No.
US 12,550,604
App. No.
18/411,456
Granted
Feb 10, 2026
Kind
B2
Abstract

Novel compounds comprising heteroleptic iridium complexes are provided. The compounds have a particular combination of ligands which includes a single pyridyl dibenzo-substituted ligand. The compounds may be used in organic light emitting devices, particularly as emitting dopants, to provide devices having improved efficiency, lifetime, and manufacturing.

Claims (45)

1 . A compound comprising a formula:

wherein the compound is a heteroleptic iridium complex;

wherein X is selected from the group consisting of NR, O, and S;

wherein R is selected from hydrogen and alkyl;

wherein R 1 , R 2 , R 3 , and R 4 may represent mono, di, tri, or tetra substitutions;

wherein each of R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkyl, and aryl;

wherein at least one R 1 , R 2 , R 3 , or R 4 is aryl; and

wherein at least one R 1 , R 2 , R 3 , or R 4 bonded to another ring is alkyl.

2 . The compound of claim 1 , wherein R 1 and R 4 are independently selected from the group consisting of hydrogen and alkyl having four or fewer carbon atoms.

3 . The compound of claim 1 , wherein R 1 and R 4 are independently selected from the group consisting of hydrogen and methyl.

4 . The compound of claim 1 , wherein R 2 and R 3 are independently selected from the group consisting of hydrogen, alkyl having four or fewer carbon atoms and aryl with 6 or fewer atoms in the ring.

5 . The compound of claim 1 , wherein R 2 and R 3 are independently selected from the group consisting of hydrogen, methyl and phenyl.

6 . The compound of claim 1 , wherein R 2 and R 3 are hydrogen.

7 . The compound of claim 1 , wherein R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkyl having four or fewer carbon atoms and aryl with 6 or fewer atoms in the ring.

8 . The compound of claim 1 , wherein R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, methyl and phenyl.

9 . The compound of claim 1 , wherein the compound has a formula selected from the group consisting of:

10 . The compound of claim 1 , wherein X is O.

11 . A first device comprising an organic light emitting device, further comprising:

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, the organic layer further comprising a compound comprising a formula:

wherein the compound is a heteroleptic iridium complex;

wherein X is selected from the group consisting of NR, O, and S;

wherein R is selected from hydrogen and alkyl;

wherein R 1 , R 2 , R 3 , and R 4 may represent mono, di, tri, or tetra substitutions;

wherein each of R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkyl, and aryl;

wherein at least one R 1 , R 2 , R 3 , or R 4 is aryl; and

wherein at least one R 1 , R 2 , R 3 , or R 4 bonded to another ring is alkyl.

12 . The compound of claim 1 , wherein the compound is selected from the group consisting of:

13 . The compound of claim 1 , wherein at least one R 1 is aryl, at least one R 2 is alkyl.

14 . The compound of claim 1 , wherein at least one R 1 is aryl, at least one R 3 is alkyl.

15 . The compound of claim 1 , wherein at least one R 4 is aryl, at least one R 1 is alkyl.

16 . The compound of claim 1 , wherein at least one R 4 is aryl, at least one R 2 is alkyl.

17 . The compound of claim 1 , wherein at least one R 4 is aryl, at least one R 3 is alkyl.

18 . The device of claim 11 , wherein the compound comprises a formula:

and

wherein X is O.

19 . A compound comprising a formula:

wherein the compound is a heteroleptic iridium complex;

wherein X is O;

wherein R 1 , R 2 , R 3 , and R 4 may represent mono, di, tri, or tetra substitutions;

wherein each of R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of hydrogen, alkyl, and aryl;

wherein at least one R 1 , R 2 , R 3 , or R 4 is aryl; and

wherein at least one R 1 , R 2 , R 3 , or R 4 bonded to another ring is alkyl.

20 . The compound of claim 19 , wherein at least one R 4 is aryl, at least one R 2 is alkyl.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 12, 2024
From: XIA, CHUANJUN; KWONG, RAYMOND; LAYEK, SUMAN
To: UNIVERSAL DISPLAY CORPORATION
Reel/Frame 066112/0199 →
Continuity (6)
Continuation 18180664 · Mar 8, 2023
Continuation 16037164 · Jul 17, 2018
Continuation 14225591 · Mar 26, 2014
Continuation 12727615 · Mar 19, 2010
Provisional Application 61162476 · Mar 23, 2009
Related Publication 20240180020A1 · May 30, 2024
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