Organic electroluminescent element
The present invention provides various organic electroluminescent elements using a material for a capping layer and a material for a luminous layer, in which the material for a capping layer uses an arylamine material that exhibit excellent stability and durability in the form of a thin film, especially a specific amine compound having a high refractive index and having a high absorbance within a wavelength range from 400 nm to 410 nm in the absorption spectrum at a concentration of 10 −5 mol/L; and in which the material for a luminous layer uses a compound containing a heterocyclic compound that has a specific fused ring structure.
1. An organic electroluminescent element comprising at least an anode, a hole transport layer, a luminous layer, an electron transport layer, a cathode and a capping layer in this order,
wherein the capping layer comprises an arylamine compound represented by a following general formula (1);
the luminous layer comprises either or both of a heterocyclic compound having a fused ring structure represented by a following general formula (2a) and a heterocyclic compound having a fused ring structure represented by a following general formula (3a-2); and
the hole transport layer comprises an arylamine compound having two triphenylamine structures in a molecule and having a structure in which the two triphenylamine structures are linked by a single bond or a divalent group not containing a hetero atom,
wherein, in the formula (1),
Ar 1 , Ar 2 , Ar 3 , and Ar 4 may be the same or different from each other and represent any one selected from a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group; and
n represents an integer of 0 to 4,
wherein at least one of Ar 1 , Ar 2 , Ar 3 , and Ar 4 is a monovalent group represented by a structural formula (B) or a structural formula (B′), or has the monovalent group as a substituent,
wherein, in the formula (B),
R 1 to R 4 may be the same or different from each other and represent a linking group as a binding site, a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a linear or branched alkyl group having 1 to 6 carbon atoms that may have a substituent group, a cycloalkyl group having 5 to 10 carbon atoms that may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms that may have a substituent group, a linear or branched alkoxy group having 1 to 6 carbon atoms that may have a substituent group, a cycloalkyloxy group having 5 to 10 carbon atoms that may have a substituent group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group;
Ar 5 and Ar 6 may be the same or different from each other and represent a linking group as a binding site, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group;
X represents a carbon atom or a nitrogen atom; and Y represents any one selected from a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom,
however, when Y is an oxygen atom or a sulfur atom, Y has no Ar 6 ; when X and Y are nitrogen atoms, X or Y has no Ar 5 or Ar 6 ; the case when X and Y are both carbon atoms; and the case when X is nitrogen atoms and Y is oxygen atoms, and the case when X is nitrogen atoms and Y is sulfur atoms are excluded; and
with the same substituted benzene ring, R 1 to R 4 may be bonded to each other, via a single bond, substituted or unsubstituted methylene group, substituted or unsubstituted amino group, oxygen atom or sulfur atom to form a ring,
wherein, in the formula (B′),
R 3 , R 4 and R 23 to R 26 may be the same or different from each other and represent a linking group, a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a linear or branched alkyl group having 1 to 6 carbon atoms that may have a substituent group, a cycloalkyl group having 5 to 10 carbon atoms that may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms that may have a substituent group, a linear or branched alkyloxy group having 1 to 6 carbon atoms that may have a substituent group, a cycloalkyloxy group having 5 to 10 carbon atoms that may have a substituent group, and a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group;
Ar 5 and Ar 6 may be the same or different from each other and represent a linking group as a binding site, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group;
X represents a carbon atom or a nitrogen atom; and Y represents any one selected from a carbon atom, a nitrogen atom, an oxygen atom, and a sulfur atom, and
however, when Y is an oxygen atom or a sulfur atom, Y has no Ar 6 ; and when X and Y are nitrogen atoms, X or Y has no Ar 5 or Ar 6 ; the case when X and Y are carbon atoms; and the case when X is nitrogen atoms and Y is oxygen atoms, and the case when X is nitrogen atoms and Y is sulfur atoms are excluded; and
with the same substituted benzene ring, R 3 , R 4 and R 23 to R 26 may be bonded to each other, via a single bond, substituted or unsubstituted methylene group, substituted or unsubstituted amino group, oxygen atom or sulfur atom to form a ring,
wherein, in the formula (2a),
X represents a sulfur atom;
A 1 represents a divalent group of a substituted or unsubstituted aromatic hydrocarbon, a divalent group of a substituted or unsubstituted aromatic heterocyclic ring, a divalent group of a substituted or unsubstituted fused polycyclic aromatic ring, or a single bond;
Ar 7 represents a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group;
R 7 and R 8 may be the same or different from each other, and represents a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, or a cycloalkyl group having 5 to 10 carbon atoms, which may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted fused polycyclic aromatic group, a substituted or unsubstituted aryloxy group, or a disubstituted amino group substituted by a group selected from an aromatic hydrocarbon group, an aromatic heterocyclic group, and a fused polycyclic aromatic group,
wherein R 7 and R 8 may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring; and R 7 and R 8 may be bonded to the substituted benzene ring to form a ring;
R 9 to R 12 may be the same or different from each other, represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, a linear or branched alkoxy group having 1 to 6 carbon atoms which may have a substituent;
R 13 and R 14 may be the same or different from each other, and are a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent,
wherein, in the formula (3a-2),
X represents a sulfur atom;
A 2 represents a bivalent group of a substituted or unsubstituted aromatic hydrocarbon, a bivalent group of a substituted or unsubstituted aromatic heterocyclic ring, a bivalent group of a substituted or unsubstituted fused polycyclic aromatic ring, or a single bond;
Ar 8 represents a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group;
R 17 and R 18 may be the same or different from each other, and represents a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 5 to 10 carbon atoms, which may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted fused polycyclic aromatic group, a substituted or unsubstituted aryloxy group, or a disubstituted amino group substituted by a group selected from an aromatic hydrocarbon group, an aromatic heterocyclic group, and a fused polycyclic aromatic group,
wherein R 17 and R 18 may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring; and R 15 to R 18 may be bonded to the substituted benzene ring to form a ring, via a substituted or unsubstituted methylene group, an oxygen atom, a sulfur atom or a linking group; and
R 19 to R 22 may be the same or different from each other, represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent.
2. The organic electroluminescent element according to claim 1 , wherein the structural formula (B) is a monovalent group represented by the structural formula (B-1) as following,
wherein, in the formula (B-1),
* represents a nitrogen atom or a binding site with any one selected from Ar 1 , Ar 2 , Ar 3 , and Ar 4 in the formula (1);
R 1 , R 2 , R 3 , and R 4 may be the same or different from each other and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent group, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic aromatic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group,
wherein, with the same substituted benzene ring, R 1 , R 2 , R 3 , and R 4 may be bonded to each other, via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.
3. The organic electroluminescent element according to claim 1 , wherein the structural formula (B) is a monovalent group represented by the structural formula (B-2) as following,
wherein, in the formula (B-2),
* represents a nitrogen atom or a binding site with any one selected from Ar 1 , Ar 2 , Ar 3 and Ar 4 in the formula (1);
R 1 , R 3 , and R 4 may be the same or different from each other and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent group, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group;
Ar 5 represents a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group; and
with the same substituted benzene ring, R 3 and R 4 may be bonded to each other, via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.
4. The organic electroluminescent element according to claim 1 , wherein the structural formula (B) is a monovalent group represented by the structural formula (B-3) as following,
wherein, in the formula (B-3),
* represents a nitrogen atom or a binding site with any one selected from Ar 1 , Ar 2 , Ar 3 and Ar 4 in the formula (1);
R 1 , R 2 , R 3 , and R 4 may be the same or different from each other and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent group, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic aromatic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group, wherein, with the same substituted benzene ring, R 1 , R 2 , R 3 , and R 4 may be bonded to each other, via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.
5. The organic electroluminescent element according to claim 1 , wherein the structural formula (B) is a monovalent group represented by the structural formula (B-4) as following,
wherein, in the formula (B-4),
* represents a nitrogen atom or a binding site with any one selected from Ar 1 , Ar 2 , Ar 3 and Ar 4 in the formula (1);
R 1 , R 3 , and R 4 may be the same or different from each other and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent group, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aryloxy group;
Ar 5 represents a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group,
wherein, with the same substituted benzene ring, R 3 and R 4 may be bonded to each other, via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.
6. The organic electroluminescent element according to claim 1 , wherein the structural formula (B) is a monovalent group represented by the structural formula (B-5) as following,
wherein, in the formula (B-5),
* represents a nitrogen atom or a binding site with any one selected from Ar 1 , Ar 2 , Ar 3 , and Ar 4 in the formula (1);
R 1 , R 2 , R 3 , and R 4 may be the same or different from each other and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent group, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent group, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent group, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted heterocyclic aromatic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group,
wherein, with the same substituted benzene ring, R 1 , R 2 , R 3 , and R 4 may be bonded to each other, via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.
7. The organic electroluminescent element according to claim 1 , wherein in the general formula (1), at least one of Ar 1 , Ar 2 , Ar 3 and Ar 4 is a monovalent group represented by the structural formula (B) or has the monovalent group represented by the structural formula (B) as a substituent.
8. The organic electroluminescent element according to claim 7 , wherein n is 0 in the general formula (1).
9. The organic electroluminescent element according to claim 7 , wherein n is 1 in the general formula (1).
10. The organic electroluminescent element according to claim 7 , wherein n is 2 in the general formula (1).
11. The organic electroluminescent element according to claim 1 , wherein in the general formula (1), any two of Ar 1 , Ar 2 , Ar 3 and Ar 4 is a monovalent group represented by the structural formula (B) or has the monovalent group as a substituent.
12. An organic electroluminescent element according to claim 1 , wherein in the general formula (1), Ar 1 and Ar 4 are monovalent group represented by the structural formula (B) or have the monovalent group as a substituent.
13. The organic electroluminescent element according to claim 1 , wherein the capping layer has a thickness in the range of 30 nm to 120 nm.
14. The organic electroluminescent element according to claim 1 , wherein a refractive index of the capping layer is 1.85 or greater within a wavelength range of 450 nm to 750 nm of light transmitted through the capping layer.
15. The organic electroluminescent element according to claim 1 , wherein the luminous layer further comprises a red luminescent material.
16. The organic electroluminescent element according to claim 14 , wherein the luminous layer further comprises a phosphorescent luminescent material.
17. The organic electroluminescent element according to claim 16 , wherein the phosphorescent luminescent material is a metal complex comprising iridium or platinum.
18. The organic electroluminescent element according to claim 1 , wherein the luminous layer comprises at least one compound selected from the group consisted of compounds represented by the following structural formulae (2-1), (2-2), (2-3), (2-4) and (3-14):
19. The organic electroluminescent element according to claim 1 , wherein the luminous layer comprises at least one compound selected from the group consisted of compounds represented by the following structural formulae (2-2) and (3-14):