LIGHT-EMITTING ELEMENT AND IRIDIUM COMPLEX

1 . A light-emitting material comprising a compound represented by a following formula (I):

wherein each of Z 1 and Z 3 represents an atomic group for forming a nitrogen-containing heteroaryl group or a nitrogen-containing heterocycloalkenyl group;

Z 2 represents an atomic group for forming an aryl group, a heteroaryl group, a cycloalkenyl group or a heterocycloalkenyl group;

Y represents an atomic group for forming a 5-membered nitrogen-containing heterocycloalkenyl group;

each of R 1 , R 2 , R 3 and R 4 represents a hydrogen atom or a substituent;

m is 1 or 2;

a is 0 or any positive integer depending upon a size of the Z 1 atomic group;

b is 0 or any positive integer depending upon a size of the Z 2 atomic group;

c is an integer of from 0 to 2; and

d is 0 or any positive integer depending upon a size of the Z 3 atomic group.

2 . The light=emitting material according to claim 1 , wherein a net effect of the (R 3 ) c group is not electron donating.

3 . The light-emitting material according to claim 1 , wherein a net effect of the (R 4 ) d group is not electron withdrawing.

4 . The light-emitting material according to claim 1 , wherein the aryl group is selected from the group consisting of a phenyl group, a naphthyl group, a diphenyl group, an anthryl group, a pyrenyl group, a phenanthryl group and fluorene.

5 . The light-emitting material according to claim 1 , wherein the cycloalkenyl group is selected from the group consisting of cyclohexene, cyclohexadiene, cyclopentane and cyclopentadiene.

6 . The light-emitting material according to claim 1 , wherein the hetrocycloalkenyl group is selected from the group consisting of pyrane, pyrroline, furan, benzofuran, thiophene, benzothiophene, pyridine, quinoline, isoquinoline, pyrazine, pyrimidine, pyrrole, pyrazole, imidazole, indole, thiazole, isothiazole, oxazole, isoxazole, benzothiazole, benzoxazole, 1,2,4-triazole, 1,2,3-triazole, tetrazole, and phenanthroline.

7 . The light-emitting material according to claim 1 , wherein each of R 1 , R 2 , R 3 and R 4 is selected from the group consisting of a hydrogen atom, a halogen atom, an aryl group, a C 1 -C 20 alkyl group, an aryl substituted C 1 -C 20 alkyl group, a C 2 -C 20 alkenyl group, a C 2 -C 20 alkynyl group, a halogen substituted C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, A C 1 -C 20 substituted amino group, a C 1 -C 20 acyl group, a C 1 -C 20 ester group, a C 1 -C 20 amide group, a halogen-substituted aryl group, a halogen-substituted aryl alkyl group, an alkyl halide-substituted aryl group, an alkyl halide-substituted aryl alkyl group, a cyano group and a nitro group.

8 . The light-emitting material according to claim 1 , wherein the compound is represented by following formula II-1, II-2, II-3, II-4, II-5, II-6 or II-31:

9 . The light-emitting material according to claim 1 , wherein the compound is represented by following formulas II-7, II-8, II-9, II-10, II-11, II-12, II-13, II-14, II-15, II-16, II-17, II-18, II-19, II-20, II-21, II-22, II-23, II-24, II-25, II-26, II-27, II-28, II-29 or II-30.

10 . A light-emitting material comprising a compound represented by a following formula (III);

wherein Z 3 represents an atomic group for forming a nitrogen-containing heteroaryl group or a nitrogen-containing heterocycloalkenyl group;

Y represents an atomic group for forming a 5-membered nitrogen-containing heterocycloalkenyl group;

each of R 3 and R 4 represents a hydrogen atom or a substituent;

R 5 represents a C 1 -C 6 alkyl group;

R 6 represents an electron-withdrawing group;

R 7 represents an aryl group, a C 1 -C 20 alkyl group or a phenyl group;

R 8 represents a alkyl group, a tert-butyl group or a trifluoromethyl group;

m is 1 or 2;

c is an integer of from 0 to 2; and

d is 0 or any positive integer depending upon a size of the Z 3 atomic group.

11 . The light-emitting material according to claim 10 , wherein a net effect of the (R 3 ) c group is not electron donating.

12 . The light-emitting material according to claim 10 , wherein a net effect of the (R 4 ) d group is not electron withdrawing.

13 . The light-emitting material according to claim 10 , wherein the R 6 group is selected from the group consisting of a halogen atom, a nitrile group, a nitro group, a carbonyl group, a cyano group and a trifluoromethyl group.

14 . The light-emitting material according to claim 10 , wherein the aryl group is selected from the group consisting of a phenyl group, a naphthyl group, a diphenyl group, an anthryl group, a pyrenyl group, a phenanthryl group and fluorene.

15 . The light-emitting material according to claim 10 , wherein the cycloalkenyl group is selected from the group consisting of cyclohexene, cyclohexadiene, cyclopentene and cyclopentadiene.

16 . The light-emitting material according to claim 10 , wherein the heterocycloalkenyl group is selected from the group consisting of pyrane, pyrroline, furan, benzofuran, thiophene, benzothiophene, pyridine, quinoline, isoquinoline, pyrazine, pyrimidine, pyrrole, pyrazole, imidazole, indole, thiazole, isothiazole, oxazole, isoxazole, benzothiazole, benzoxazole, 1,2,4-triazole, 1,2,3-triazole, tetrazole, and phenanthroline.

17 . An organic light-emitting diode (OLED) device which includes an anode, a cathode and an electroluminescent region interposed between the anode and the cathode, wherein the electroluminescent region includes an emitter layer comprising a phosphorescent iridium complex represented by a following formula (I):

wherein each of Z 1 and Z 3 represents an atomic group for forming a nitrogen-containing heteroaryl group or a nitrogen-containing heterocycloalkenyl group;

Z 2 represents an atomic group for forming an aryl group, a heteroaryl group, a cycloalkenyl group or a heterocycloalkenyl group;

Y represents an atomic group for forming a 5-membered nitrogen-containing heterocycloalkenyl group;

each of R 1 , R 2 , R 3 and R 4 represents a hydrogen atom or a substituent;

m is 1 or 2;

a is 0 or any positive integer depending upon a size of the Z 1 atomic group;

b is 0 or any positive integer depending upon a size of the Z 2 atomic group;

c is an integer of from 0 to 2, and

d is 0 or any positive integer depending upon a size of the Z 3 atomic group.

18 . The OLED device according to claim 17 , wherein a net effect of the (R 3 ) c group is not electron donating.

19 . The OLED device according to claim 17 , wherein a net effect of the (R 4 ) d is not electron withdrawing.

20 . The OLED device according to claim 17 , wherein the aryl group is selected from the group consisting of a phenyl group, a naphthyl group, a diphenyl group, an anthryl group, a pyrenyl group, a phenanthryl group and fluorene.

21 . The OLED device according to claim 17 , wherein the cycloalkenyl group is selected from the group consisting of cyclohexene, cyclohexadiene, cyclopentene and cyclopentadiene.

22 . The OLED device according to claim 17 , wherein the heterocycloalkenyl group is selected from the group consisting of pyrane, pyrroline, furan, benzofuran, thiophene, benzothiophene, pyridine, quinoline, isoquinoline, pyrazine, pyrimidine, pyrrole, pyrazole, imidazole, indole, thiazole, isothiazole, oxazole, isoxazole, benzothiazole, benzoxazole, 1,2,4-triazole, 1,2,3-triazole, tetraazole, and phenanthroline.

23 . The OLED device according to claim 17 , wherein each of R 1 , R 2 , R 3 and R 4 is selected from the group consisting of a hydrogen atom, a halogen atom, an aryl group, a C 1 -C 20 alkyl group, an aryl substituted C 1 -C 20 alkyl group, a C 2 -C 20 alkenyl group, a C 2 -C 20 alkynyl group, a halogen substituted C 1 -C 20 alkyl group, A C 1 -C 20 alkoxy group, a C 1 -C 20 substituted amino group, a C 1 -C 20 acyl group, a C 1 -C 20 ester group, a C 1 -C 20 amide group, a halogen-substituted aryl group, a halogen-substituted aryl alkyl group, an alkyl halide-substituted aryl group, an alkyl halide-substituted aryl alkyl group, a cyano group and a nitro group.

24 . The OLED device according to claim 17 , wherein the emitter layer includes the compound represented by following formulas II-1, II-2, II-3, II-4, II-5 or II-6:

25 . The OLED device according to claim 17 , wherein the emitter layer includes the compound represented by following formulas II-7, II-8, II-9, II-10, II-11, II-12, II-13, II-14, II-15, II-16, II-17, II-18, II-19, II-20, II-21, II-22, II-23, II-24, II-25, II-26, II-27, II-28, II-29, or II-30;

26 . The OLED device according to claim 17 , wherein the emitter layer further includes a host luminescent compound doped with the iridium complex.

27 . The OLED device according to claim 26 , wherein the host luminescent compound is represented by a following structural formula:

28 . The OLED device according to claim 17 , wherein the electroluminescent region further includes a hole transfer layer interposed between the anode and the emitter layer, and the hole transfer layer comprises a compound represented by a following structural formula of H1 or H2;

29 . The OLED device according to claim 17 , wherein the electroluminescent region further includes a hole-blocking layer interposed between the cathode and the emitter layer and in contact with the emitter layer, and the hole-blocking layer comprises a compound represented by a following structural formula:

wherein the Ph group is a phenyl group, and the Me group is a methyl group.

30 . The OLED device according to claim 17 , wherein the electroluminescent region further includes an electron-transporting layer interposed between the hole-blocking layer and the cathode, and the hole-blocking layer comprises a compound represented by a following structural formula:

31 . An OLED device which includes an anode, a cathode and an electroluminescent region interposed between the anode and the cathode, wherein the electroluminescent region includes an emitter layer comprising a phosphorescent iridium complex represented by a following formula (III):

wherein Z 3 represents an atomic group for forming a nitrogen-containing heteroaryl group or a nitrogen-containing heterocycloalkenyl group;

Y represents an atomic group for forming a 5membered nitrogen-containing heterocycloalkenyl group;

each of R 3 and R 4 represents a hydrogen atom or a substituent;

R 5 represents a C 1 -C 6 alkyl group;

R 6 represents an electron-withdrawing group;

R 7 represents an aryl group, a C 1 -C 20 alkyl group or a phenyl group;

R 8 represents a alkyl group, a tert-butyl group or a trifluoromethyl group;

m is 1 or 2;

c is an integer of from 0 to 2; and

d is 0 or any positive integer depending upon a size of the Z 3 atomic group.

32 . The OLED device according to claim 31 , wherein a net effect of the (R 3 ) c group is not electron donating.

33 . The OLED device according to claim 31 , wherein a net effect of the (R 4 ) d is not electron withdrawing.

34 . The OLED device according to claim 31 , wherein the R 6 group is selected from the group consisting of a halogen atom, a nitrile group, a nitro group, a carbonyl group, a cyano group and a trifluoromethyl group.

35 . The OLED device according to claim 31 , wherein the aryl group is selected from the group consisting of a phenyl group, a naphthyl group, a diphenyl group, an anthryl group, a pyrenyl group, a phenanthryl group and fluorene.

36 . The OLED device according to claim 31 , wherein the cycloalkenyl group is selected from the group consisting of cyclohexene, cyclohexadiene, cyclopentene and cyclopentadiene.

37 . The OLED device according to claim 31 , wherein the heterocycloalkenyl group is selected from the group consisting of pyrane, pyrroline, furan, benzofuran, thiophene, benzothiophene, pyridine, quinoline, isoquinoline, pyrazine, pyrimidine, pyrrole, pyrazole, imidazole, indole, thiazole, isothiazole, oxazole, isoxazole, benzothiazole, benzoxazole, 1,2,4,-triazole, 1,2,3-triazole, tetrazole, and phenanthroline.

38 . The OLED device according to claim 31 , wherein the emitter layer further includes a host luminescent compound doped with the iridium complex.

39 . The OLED device according to claim 31 , wherein the host luminescent compound is represented by a following structural formula:

40 . The OLED device according to claim 31 , wherein the electroluminescent region further includes a hole transfer layer interposed between the anode and the emitter layer, and the hole transfer layer comprises a compound represented by a following structural formula of H1 or H2:

41 . The OLED device according to claim 31 , wherein the electroluminescent region further includes a hole-blocking layer interposed between the cathode and the emitter layer and in contact with the emitter layer, and the hole-blocking layer comprises a compound represented by a following structural formula:

wherein the Ph group is a phenyl group, and the Me group is a methyl group.

42 . The OLED device according to claim 31 , wherein the electroluminescent region further includes an electron-transporting layer interposed between the hole-blocking layer and the cathode, and the hole-blocking layer comprises a compound represented by a following structural formula: