Organic electroluminescent element, white light emission element, full color display device and lighting device
An organic electroluminescent element comprising a metal complex represented by Formula (1), wherein Z is a hydrocarbon ring or a heterocyclic ring, provided that each of the hydrocarbon ring and the heterocyclic ring has a substituent having a steric parameter (Es) of −0.5 or less at the third atom of the ring counted from a nitrogen atom attached to Z, the nitrogen atom being counted as the first atom, X, Y, A, B, X 1 -L1-X 2 , M 1 , m1 and m2 are described in the specification.
1. A white light emitting organic electroluminescent element comprising at least two dopants, provided that one of the two dopants is a metal complex selected from the group of compounds consisting of compounds (154), (159), and (176):
and the other one of the two dopants is a phosphorescent iridium compound having a structure that is different from Formula (4),
wherein R and R′ are a substituent having a steric parameter (Es) of −0.5 or less;
R 1 represents an alkyl group, an alkoxy group, a halogen atom, an aryl group, or a heterocyclic group, n1 is an integer of 0 to 4;
R 2 represents an alkyl group, a cycloalkyl group, or an aryl group, n2 is an integer of 0 to 2;
R 3 represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a halogen atom or an amino group, n3 is an integer of 0 to 3;
X 1 -L1-X 2 is a bidentate ligand, provided that each X 1 and X 2 is independently a carbon atom, a nitrogen atom or an oxygen atom, and that L1 is a group of atoms necessary to form the bidentate ligand with X 1 and X 2 ;
m1 is an integer of 1 to 3, and m2 is an integer of 0 to 2, provided that a sum of m1 and m2 is 2 or 3; and
M 1 is an iridium atom,
wherein the electroluminescent element comprises an emission layer which contains a dibenzofuran derivative substituted with a nitrogen containing heterocycle, wherein the nitrogen containing heterocycle is selected from the group consisting of a carbazole group, a carboline derivative, and a derivative having a ring structure in which at least one carbon atoms of the carboline ring is substituted with a nitrogen atom.
2. The organic electroluminescent element of claim 1 , wherein the emission layer comprises:
(i) a carboline derivative; or
(ii) a condensed ring compound having a structure derived from carboline, wherein at least one of carbon atoms of a hydrocarbon ring in a carboline ring is substituted with a nitrogen atom.
3. The organic electro luminescent element of claim 1 a positive hole inhibition layer as a constituting layer of the element, the positive hole inhibition layer containing:
(i) a carboline derivative; or
(ii) a condensed ring compound having a structure derived from carboline, wherein at least one of carbon atoms of a hydrocarbon ring in a carboline ring is substituted with a nitrogen atom.
4. The organic electroluminescent element of claim 3 , further comprising a green light emitting dopant and a red light emitting dopant.
5. A display device comprising the organic electroluminescent element of claim 3 .
6. A lighting device comprising the organic electroluminescent element of claim 3 .
7. A display device comprising the organic electroluminescent element of claim 1 .
8. The display device of claim 7 which is capable of producing a full color image.
9. A lighting device comprising the organic electroluminescent element of claim 1 .
10. The organic electroluminescent element of claim 1 , further comprising a green light emitting dopant and a red light emitting dopant.