ORGANIC ELECTROLUMINESCENCE DEVICE
An organic electroluminescence device includes an anode, an emitting layer, a blocking layer, an electron injecting layer, and a cathode in sequential order. The emitting layer includes a host and dopant. The blocking layer includes an aromatic heterocyclic derivative. A triplet energy E T b (eV) of the blocking layer is larger than a triplet energy E T h (eV) of the host. An affinity A b (eV) of the blocking layer and an affinity A b (eV) of the electron injecting layer satisfy a relationship of A e −A b <0.2.
1 . An organic electroluminescence device comprising an anode, an emitting layer, a blocking layer, an electron injecting layer, and a cathode in sequential order, wherein
the emitting layer comprises a host and a dopant,
the blocking layer comprises an aromatic heterocyclic derivative,
a triplet energy E T b (eV) of the aromatic heterocyclic derivative is larger than a triplet energy E T h (eV) of the host, and
an affinity A b (eV) of the blocking layer and an affinity A, (eV) of the electron injecting layer satisfy a relationship of A e −A b <0.2.
2 . The organic electroluminescence device according to claim 1 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and the triplet energy E T h (eV) of the host satisfy a relationship of E T h +0.2<E T b
3 . The organic electroluminescence device according to claim 1 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and the triplet energy E T h (eV) of the host satisfy a relationship of E T h +0.3<E T b
4 . The organic electroluminescence device according to claim 1 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and the triplet energy E T h (eV) of the host satisfy a relationship of E T h +0.4<E T b
5 . The organic electroluminescence device according to claim 1 , wherein
the aromatic heterocyclic derivative included in the blocking layer has six or more cyclic structures, and
the triplet energy E T b (eV) of the aromatic heterocyclic derivative having the six or more cyclic structures is larger than the triplet energy E T h (eV) of the host.
6 . The organic electroluminescence device according to claim 1 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and a triplet energy E T Alq (eV) of tris(8-quinolinolato)aluminum complex satisfy a relationship of E T b >E T Alq .
7 . The organic electroluminescence device according to claim 1 , wherein
an electron mobility of the aromatic heterocyclic derivative is 10 −6 cm 2 /Vs or more in an electric field intensity of 0.04 MV/cm to 0.5 MV/cm.
8 . The organic electroluminescence device according to claim 1 , wherein
an electron mobility of a material for forming the electron injecting layer is 10 −6 cm 2 /Vs or more in an electric field intensity of 0.04 MV/cm to 0.5 MV/cm.
9 . The organic electroluminescence device according to claim 1 , wherein
the dopant exhibits a fluorescent emission of a main peak wavelength of 550 nm or less, and
a triplet energy E T d (eV) of the dopant is larger than the triplet energy E T h (eV) of the host.
10 . The organic electroluminescence device according to claim 1 , wherein
a hole transporting zone is provided between the anode and the emitting layer,
a hole transporting layer is adjacent to the emitting layer in the hole transporting zone, and
a triplet energy E T ho (eV) of the hole transporting layer is larger than the triplet energy E T h (eV) of the host.
11 . The organic electroluminescence device according to claim 1 , wherein
a material for forming the electron injecting layer is the same as a material for forming the blocking layer.
12 . The organic electroluminescence device according to claim 1 , wherein
a material for forming the electron injecting layer is the same as a material for forming the blocking layer, and
the electron injecting layer is doped with a donor.
13 . The organic electroluminescence device according to claim 1 , wherein
the dopant is at least one compound selected from the group consisting of a pyrene derivative, aminoanthracene derivative, aminochrysene derivative, aminopyrene derivative, fluoranthene derivative and boron complex.
14 . The organic electroluminescence device according to claim 1 , wherein
the host is a compound that contains a double bond only in a cyclic structure.
15 . The organic electroluminescence device according to claim 1 , wherein
the dopant is a compound that contains a double bond only in a cyclic structure.
16 . An organic electroluminescence device comprising an anode, an emitting layer, a blocking layer, an electron injecting layer, and a cathode in sequential order, wherein
the emitting layer comprises a host and a dopant,
the blocking layer comprises an aromatic heterocyclic derivative,
a triplet energy E T b (eV) of the aromatic heterocyclic derivative is larger than a triplet energy E T h (eV) of the host, and
the aromatic heterocyclic derivative has an azine ring.
17 . The organic electroluminescence device according to claim 16 , wherein
the aromatic heterocyclic derivative is represented by a formula (1) below,
where: HAr represents a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, and when a plurality of HAr are present, the plurality of HAr are mutually the same or different;
Az represents a substituted or unsubstituted pyrimidine, a substituted or unsubstituted pyrazine, a substituted or unsubstituted pyridazine, or a substituted or unsubstituted triazine;
L represents a single bond, a divalent to tetravalent residue of a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring carbon atoms, a divalent to tetravalent residue of a substituted or unsubstituted heterocylic ring having 5 to 30 ring atoms, or a divalent to tetravalent residue formed by combination in a single bond of two to three rings selected from the aromatic hydrocarbon ring and the heterocyclic ring;
a is an integer of 1 to 3; and
b is an integer of 1 to 3.
18 . The organic electroluminescence device according to claim 16 , wherein
an electron mobility of the aromatic heterocyclic derivative is 10 −6 cm 2 /Vs or more in an electric field intensity of 0.04 MV/cm to 0.5 MV/cm.
19 . The organic electroluminescence device according to claim 16 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and the triplet energy E T h (eV) of the host satisfy a relationship of E T h +0.2<E T b .
20 . The organic electroluminescence device according to claim 16 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and the triplet energy E T h (eV) of the host satisfy a relationship of E T h +0.3<E T b
21 . The organic electroluminescence device according to claim 16 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and the triplet energy E T h (eV) of the host satisfy a relationship of E T h +0.4<E T b
22 . The organic electroluminescence device according to claim 16 , wherein
the aromatic heterocyclic derivative included in the blocking layer has six or more cyclic structures, and
the triplet energy E T b (eV) of the aromatic heterocyclic derivative having the six or more cyclic structures is larger than a triplet energy E T h (eV) of the host.
23 . The organic electroluminescence device according to claim 16 , wherein
an electron mobility of a material for forming the electron injecting layer is 1×10 −6 cm 2 /Vs or more in an electric field intensity of 0.04 MV/cm to 0.5 MV/cm.
24 . The organic electroluminescence device according to claim 16 , wherein
the dopant exhibits a fluorescent emission of a main peak wavelength of 550 nm or less, and
a triplet energy E T d (eV) of the dopant is larger than the triplet energy E T h (eV) of the host.
25 . The organic electroluminescence device according to claim 16 , wherein
a hole transporting zone is provided between the anode and the emitting layer,
a hole transporting layer is adjacent to the emitting layer in the hole transporting zone, and
a triplet energy E T ho (eV) of the hole transporting layer is larger than the triplet energy E T h (eV) of the host.
26 . The organic electroluminescence device according to claim 16 , wherein
a material for forming the electron injecting layer is the same as a material for forming the blocking layer.
27 . The organic electroluminescence device according to claim 16 , wherein
a material for forming the electron injecting layer is the same as a material for forming the blocking layer, and
the electron injecting layer is doped with a donor.
28 . The organic electroluminescence device according to claim 16 , wherein
the dopant is at least one compound selected from the group consisting of a pyrene derivative, aminoanthracene derivative, aminochrysene derivative, aminopyrene derivative, fluoranthene derivative and boron complex.
29 . The organic electroluminescence device according to claim 16 , wherein
the host is a compound that contains a double bond only in a cyclic structure.
30 . The organic electroluminescence device according to claim 16 , wherein
the dopant is a compound that contains a double bond only in a cyclic structure.