Organic electroluminescence device
An organic electroluminescence device 1 includes: an anode 3 , a cathode 4 opposed to the anode 3 and an emitting layer 5 provided between the anode 3 and the cathode 4 . The emitting layer 5 contains first and second host materials and a luminescent material. The first host material has a partial structure represented by at least one of the following formulae (1) and (2) while the second host material has a partial structure represented by the following formula (3). Az represents a substituted or unsubstituted aromatic heterocyclic group containing a nitrogen-containing six-membered ring. W CN is an aromatic hydrocarbon group substituted by at least one cyano group (CN) or an aromatic heterocyclic group substituted by at least one cyano group (CN). Ar 1 is a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group, but is not an aromatic heterocyclic group containing a nitrogen-containing six-membered ring. —Az—(W CN ) p (1) —Az—(CN) q (2) —Ar 1 —(CN) r (3)
1. An organic electroluminescence device comprising:
an anode;
a cathode opposed to the anode; and
an emitting layer provided between the anode and the cathode, wherein
the emitting layer comprises a first host material, a second host material and a luminescent material,
the first host material comprises a partial structure represented by at least one of the following formulae (1) and (2), and
the second host material comprises a partial structure represented by the following formula (3) and does not comprise a partial structure represented by the formula (1) or the formula (2),
-Az-(W CN ) p (1)
-Az-(CN) q (2)
—Ar 1 —(CN) r (3)
where: in the formula (1),
Az represents a substituted or unsubstituted aromatic heterocyclic group comprising a nitrogen-containing six-membered ring,
W CN is an aromatic hydrocarbon group substituted by at least one cyano group (CN) or an aromatic heterocyclic group substituted by at least one cyano group (CN),
p is an integer of 1 or more, and
W CN optionally comprises a substituent other than the cyano group and, when a plurality of W CN are present, the plurality of W CN are mutually the same or different;
In the formula (2),
Az represents the same as Az of the formula (1), and
q is an integer of 1 or more; and
in the formula (3),
Ar 1 is a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group, but is not an aromatic heterocyclic group comprising a nitrogen-containing six-membered ring, and
r is an integer of 1 or more.
2. The organic electroluminescence device according to claim 1 , wherein
the first host material is represented by at least one of the formulae (1-1) and (2-1), and
the second host material is represented by the following formula (3-1),
Ar 2 -Az-(W CN ) p (1-1)
Ar 2 -Az-(CN) q (2-1)
Ar 3 —Ar 1 —(CN) r (3-1)
where:
Ar 2 and Ar 3 each independently represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms,
Az, W CN and p in the formula (1-1) are the same as Az, W CN and p in the formula (1),
Az and q in the formula (2-1) are the same as Az and q in the formula (2), and
Ar 1 and r in the formula (3-1) are the same as Ar 1 and r in the formula (3).
3. The organic electroluminescence device according to claim 1 , wherein
the first host material is represented by the following formula (4),
where:
M 1 represents a group represented by one of the formulae (1) and (2),
L 1 represents a single bond, a substituted or unsubstituted polyvalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted polyvalent aromatic heterocyclic group having 5 to 30 ring atoms, a cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the polyvalent aromatic hydrocarbon group, the polyvalent aromatic heterocyclic group and the cycloalkylene group,
k is 1 or 2,
X 11 to X 18 each independently represent a nitrogen atom or CR b ,
R b each independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 30 ring carbon atoms, and a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, and
a part of one of adjacent two R b in X 11 to X 18 is optionally bonded to a part of the other R b to form a cyclic structure.
4. The organic electroluminescence device according to claim 1 , wherein
the second host material is represented by the following formula (5),
where:
A 1 represents a group represented by the formula (3),
X 1 to X 8 each independently represent N (nitrogen atom) or CR a ,
R a each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, a halogen atom, or a cyano group, when a plurality of R a are present, the plurality of R a are the same or different, and
when at least adjacent two of X 1 to X 4 and X 5 to X 8 are CR a , a part of R a in the adjacent CR a is optionally bonded to a part of the other R a to form a cyclic structure.
5. The organic electroluminescence device according to claim 3 , wherein
the first host material is represented by at least one of the following formulae (4-3) and (4-4),
where:
L 1 and X 11 to X 18 are the same as L 1 and X 11 to X 18 in the formula (4),
Az, W CN and p in the formula (4-3) are the same as Az, W CN and p in the formula (1), and
Az and q in the formula (4-4) are the same as Az and q in the formula (1).
6. The organic electroluminescence device according to claim 4 , wherein
the first host material is represented by at least one of the following formulae (4-3) and (4-4),
where:
L 1 represents a single bond, a substituted or unsubstituted polyvalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted polyvalent aromatic heterocyclic group having 5 to 30 ring atoms, a cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the polyvalent aromatic hydrocarbon group, the polyvalent aromatic heterocyclic group and the cycloalkylene group,
X 11 to X 18 each independently represent a nitrogen atom or CR b ,
R b each independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 30 ring carbon atoms, and a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, and
a part of one of adjacent two R b in X 11 to X 18 is optionally bonded to a part of the other R b to form a cyclic structure,
Az, W CN and p in the formula (4-3) are the same as Az, W CN and p in the formula (1), and
Az and q in the formula (4-4) are the same as Az and q in the formula (1).
7. The organic electroluminescence device according to claim 1 , wherein
the second host material is represented by the following formula (5-1),
where:
A 1 represents the group having the partial structure represented by the formula (3),
A 2 each independently represents the group having the partial structure represented by the formula (3), a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms,
A 3 represents a substituted or unsubstituted divalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted divalent aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the divalent aromatic hydrocarbon group, the divalent aromatic heterocyclic group and the cycloalkylene group,
m is an integer of 0 to 3,
X 1 to X 4 and Y 5 to Y 8 each independently represent N (nitrogen atom) or CR a ,
X 5 to X 8 and Y 1 to Y 4 each independently represent N (nitrogen atom), CR a or a carbon atom to be bonded to A 3 ,
R a in X 1 to X 8 and Y 1 to Y 8 each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, a halogen atom, or a cyano group,
when a plurality of R a are present, the plurality of R a are the same or different, and
when at least adjacent two of X 1 to X 8 and Y 1 to Y 8 are CR a , a part of R a in the adjacent CR a is optionally bonded to a part of the other R a to form a cyclic structure.
8. The organic electroluminescence device according to claim 3 , wherein
the second host material is represented by the following formula (5-1),
where:
A 1 represents the group having the partial structure represented by the formula (3),
A 2 each independently represents the group having the partial structure represented by the formula (3), a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms,
A 3 represents a substituted or unsubstituted divalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted divalent aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the divalent aromatic hydrocarbon group, the divalent aromatic heterocyclic group and the cycloalkylene group,
m is an integer of 0 to 3,
X 1 to X 4 and Y 5 to Y 8 each independently represent N (nitrogen atom) or CR a ,
X 5 to X 8 and Y 1 to Y 4 each independently represent N (nitrogen atom), CR a or a carbon atom to be bonded to A 3 ,
R a in X 1 to X 8 and Y 1 to Y 8 each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, a halogen atom, or a cyano group,
when a plurality of R a are present, the plurality of R a are the same or different, and
when at least adjacent two of X 1 to X 8 and Y 1 to Y 8 are CR a , a part of R a in the adjacent CR a is optionally bonded to a part of the other R a to form a cyclic structure.
9. The organic electroluminescence device according to claim 5 , wherein
the second host material is represented by the following formula (5-1),
where:
A 1 represents the group having the partial structure represented by the formula (3),
A 2 each independently represents the group having the partial structure represented by the formula (3), a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms,
A 3 represents a substituted or unsubstituted divalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted divalent aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the divalent aromatic hydrocarbon group, the divalent aromatic heterocyclic group and the cycloalkylene group,
m is an integer of 0 to 3,
X 1 to X 4 and Y 5 to Y 8 each independently represent N (nitrogen atom) or CR a ,
X 5 to X 8 and Y 1 to Y 4 each independently represent N (nitrogen atom), CR a or a carbon atom to be bonded to A 3 ,
R a in X 1 to X 8 and Y 1 to Y 8 each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, a halogen atom, or a cyano group,
when a plurality of R a are present, the plurality of R a are the same or different, and
when at least adjacent two of X 1 to X 8 and Y 1 to Y 8 are CR a , a part of R a in the adjacent CR a is optionally bonded to a part of the other R a to form a cyclic structure.
10. The organic electroluminescence device according to claim 3 , wherein
the first host material is represented by the following formula (4-5),
where:
L 1 represents the same as L 1 in the formula (4),
X 11 to X 14 and X 45 to X 48 each independently represent a nitrogen atom or CR b ,
X 15 to X 18 and X 41 to X 44 each independently represent a nitrogen atom, CR b or a carbon atom to be bonded to L 2 ,
R b of CR b in X 11 to X 18 and X 41 to X 48 is the same as R b of CR b in X 11 to X 18 in the formula (4),
L 2 and L 3 each independently represent a single bond, a substituted or unsubstituted divalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted divalent aromatic heterocyclic group having 5 to 30 ring atoms, a cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the divalent aromatic hydrocarbon group, the divalent aromatic heterocyclic group and the cycloalkylene group,
a part of one of at least adjacent two R b in X 11 to X 18 and X 41 to X 48 is optionally bonded to a part of the other R b to form a cyclic structure,
M 1 represents a group represented by one of the formulae (1) and (2),
M 2 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, or a group represented by one of the formulae (1) and (2), and
M 1 and M 2 are the same or different.
11. The organic electroluminescence device according to claim 7 , wherein
the first host material is represented by the following formula (4-5),
where:
L 1 represents a single bond, a substituted or unsubstituted polyvalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted polyvalent aromatic heterocyclic group having 5 to 30 ring atoms, a cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the polyvalent aromatic hydrocarbon group, the polyvalent aromatic heterocyclic group and the cycloalkylene group,
X 11 to X 14 and X 45 to X 48 each independently represent a nitrogen atom or CR b ,
X 15 to X 18 and X 41 to X 44 each independently represent a nitrogen atom, CR b or a carbon atom to be bonded to L 2 ,
R b of CR b in X 11 to X 18 and X 41 to X 48 each independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 30 ring carbon atoms, and a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms,
L 2 and L 3 each independently represent a single bond, a substituted or unsubstituted divalent aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted divalent aromatic heterocyclic group having 5 to 30 ring atoms, a cycloalkylene group having 5 to 30 ring carbon atoms, or a group provided by linking the divalent aromatic hydrocarbon group, the divalent aromatic heterocyclic group and the cycloalkylene group,
a part of one of at least adjacent two R b in X 11 to X 18 and X 41 to X 48 is optionally bonded to a part of the other R b to form a cyclic structure,
M 1 represents a group represented by one of the formulae (1) and (2),
M 2 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, or a group represented by one of the formulae (1) and (2), and
M 1 and M 2 are the same or different.
12. The organic electroluminescence device according to claim 1 , wherein
Az is a divalent to pentavalent group of a ring represented by the following formula (4-6),
where:
Y 11 to Y 15 each independently represent a nitrogen atom (N) or CR c ,
R c of CR c each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, or a halogen atom,
when adjacent two of Y 11 to Y 15 are CR c , a part of R c of the adjacent CR c is optionally bonded to a part of the other R c to form a cyclic structure,
when a plurality of R c are present, the plurality of R c are mutually the same or different.
13. The organic electroluminescence device according to claim 3 , wherein
Az is a divalent to pentavalent group of a ring represented by the following formula (4-6),
where:
Y 11 to Y 15 each independently represent a nitrogen atom (N) or CR c ,
R c of CR c each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, or a halogen atom,
when adjacent two of Y 11 to Y 15 are CR c , a part of R c of the adjacent CR c is optionally bonded to a part of the other R c to form a cyclic structure, and
when a plurality of R c are present, the plurality of R c are mutually the same or different.
14. The organic electroluminescence device according to claim 5 , wherein
Az a divalent to pentavalent group of a ring represented by the following formula (4-6),
where:
Y 11 to Y 15 each independently represent a nitrogen atom (N) or CR c ,
R c of CR c each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, or a halogen atom,
when adjacent two of Y 11 to Y 15 are CR c , a part of R c of the adjacent CR c is optionally bonded to a part of the other R c to form a cyclic structure, and
when a plurality of R c are present, the plurality of R c are mutually the same or different.
15. The organic electroluminescence device according to claim 10 , wherein
Az a divalent to pentavalent group of a ring represented by the following formula (4-6),
where:
Y 11 to Y 15 each independently represent a nitrogen atom (N) or CR c ,
R c of CR c each independently represents a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group, or a halogen atom,
when adjacent two of Y 11 to Y 15 are CR c , a part of R c of the adjacent CR c is optionally bonded to a part of the other R c to form a cyclic structure, and
when a plurality of R c are present, the plurality of R c are mutually the same or different.
16. The organic electroluminescence device according to claim 10 , wherein
the first host material represented by the formula (4-5) is represented by one of the following formulae (4-5-1), (4-5-2) and (4-5-3),
where: M 1 , M 2 , L 1 , L 2 , L 3 , X 11 to X 18 , and X 41 to X 48 represent the same as M 1 , M 2 , L 1 , L 2 , L 3 , X 11 to X 18 , and X 41 to X 48 in the formula (4-5).
17. The organic electroluminescence device according to claim 7 , wherein
the second host material represented by the formula (5-1) is preferably represented by one of the following formulae (5-1-1), (5-1-2) and (5-1-3),
where:
in the formula (5-1-1),
A 1 , A 2 , A 3 , X 1 to X 5 , X 7 , X 8 , Y 1 , Y 2 , Y 4 to Y 8 and m represent the same as A 1 , A 2 , A 3 , X 1 to X 5 , X 7 , X 8 , Y 1 , Y 2 , Y 4 to Y 8 and m in the formula (5-1), and X 6 and Y 3 are carbon atoms,
in the formula (5-1-2),
A 1 , A 2 , A 3 , X 1 to X 5 , X 7 , X 8 , Y 1 , Y 3 to Y 8 and m represent the same as A 1 , A 2 , A 3 , X 1 to X 5 , X 7 , X 8 , Y 1 , Y 3 to Y 8 and m in the formula (5-1), and X 6 and Y 2 are carbon atoms, and
in the formula (5-1-3),
A 1 , A 2 , A 3 , X 1 to X 6 , X 8 , Y 1 , Y 2 , Y 4 to Y 8 and m represent the same as A 1 , A 2 , A 3 , X 1 to X 6 , X 8 , Y 1 , Y 2 , Y 4 to Y 8 and m in the formula (5-1), and X 7 and Y 3 are carbon atoms.
18. The organic electroluminescence device according to claim 1 , wherein
at least one of the partial structures represented by the formula (3) of the second host material is a cyano-substituted phenyl group, a cyano-substituted naphthyl group, a cyano-substituted phenanthryl group, a cyano-substituted dibenzofuranyl group, a cyano-substituted biphenylyl group, a cyano-substituted terphenylyl group, or a cyano-substituted triphenylenyl group.
19. The organic electroluminescence device according to claim 1 , wherein
the luminescent material comprises a phosphorescent material that is an ortho-metalated complex of a metal atom selected from iridium (Ir), osmium (Os) and platinum (Pt).
20. The organic electroluminescence device according to claim 19 , wherein
a wavelength of an emission peak of the phosphorescent material is 490 nm to 700 nm.