JP2020061390A - Composition, material for organic electroluminescent element, composition film, organic electroluminescent element, and electronic equipment - Google Patents

Abstract

To provide a composition which enables performance of an organic electroluminescent element to be maintained and furthermore enables material from one evaporation source to be vapor-deposited at a stable a ratio of the material.SOLUTION: The composition is provided that is obtained by mixing two or more kinds chemical compounds, and contains at least a first chemical compound and a second chemical compound which are expressed by a specific general formula.SELECTED DRAWING: None

Description

  The present invention relates to a composition, a material for an organic electroluminescence device, a composition film, an organic electroluminescence device, and an electronic device.

  In Patent Documents 1 and 2, a biscarbazole derivative having a specific structure having a cyano group is used as a first host, and a compound having both a carbazolyl group derivative structure and a nitrogen-containing heteroaromatic ring is used as a second host. The organic electroluminescence device described above is described. It is described in Patent Document 1 and Patent Document 2 that the organic electroluminescent element has a long life.

International Publication No. 2013/084885 International Publication No. 2013/145923

When two materials (for example, a first host and a second host) are vapor-deposited from different vapor deposition sources as in Patent Document 1 and Patent Document 2, there is a problem that the manufacturing process of the organic electroluminescent element becomes complicated. . On the other hand, the life of the organic electroluminescence device using one material (for example, only the first host or the second host) is shortened. Therefore, a technique for stably depositing two (or a plurality of) materials from one vapor deposition source is desired.
In the combination of the first host and the second host described in Patent Document 1 and Patent Document 2, when vapor deposition from one vapor deposition source, the ratio of the first host and the second host contained in the formed layer is not stable. However, there is a problem that the performance of the organic electroluminescence device is not stable.

  An object of the present invention is to provide a composition capable of stably depositing a ratio of materials from one deposition source while maintaining the performance of the organic electroluminescent element, and an organic electroluminescent element including the composition. To provide a material for use, to provide a composition film containing the composition, to provide an organic electroluminescent device containing the composition, and to provide an electronic device including the organic electroluminescent device. .

  According to one embodiment of the present invention, a composition in which two or more compounds are mixed is represented by at least a first compound represented by the following general formula (1) and a general formula (2) below. A composition is provided that includes a second compound.

(In the general formula (1),
R ^{1 to} R ⁴ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 24 ring carbon atoms, or a cyano group.
a is 0, 1, 2, 3, or 4.
b is 0, 1, 2, or 3.
c is 0, 1, 2, or 3.
d is 0, 1, 2, 3 or 4.
When a is 2 or more, a plurality of R ^1's are the same or different from each other.
When b is 2 or more, plural R ² are the same or different from each other.
When c is 2 or more, a plurality of R ^3's are the same as or different from each other.
When d is 2 or more, a plurality of R ^4's are the same as or different from each other.
A ¹ and A ² are each independently
A substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heterocyclic group having 6 to 30 ring-forming atoms is shown.
However, six ring structures represented by the following general formula (1a) are contained in total in R ^{1 to} R ⁴ , A ¹ and A ² . )

(In the general formula (1a), X ¹ , X ² and X ³ each independently represent CR ^X or N. At least one of the six ring structures represented by the general formula (1a). In the ring structure of, at least one of X ¹ , X ² and X ³ represents N. In the case where the ring structures represented by the general formula (1a) are bonded to each other to form a condensed ring. There are cases where it does not.
R ^X , R ^X1 , R ^X2, and R ^X3 are each independently
Single bond,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
When there are a plurality of R ^x , the plurality of R ^x are the same or different from each other.
At least one of R ^X1 , R ^X2 , R ^X3 and one or more R ^X is a single bond. )

(In the general formula (2), R ^{21 to} R ²⁴ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 30 ring carbon atoms, or a cyano group.
e is 0, 1, 2, 3, or 4.
f is 0, 1, 2, or 3.
g is 0, 1, 2, or 3.
h is 0, 1, 2, 3, or 4.
When e is 2 or more, a plurality of R ^21's are the same as or different from each other.
When f is 2 or more, a plurality of R ^22's are the same as or different from each other.
When g is 2 or more, a plurality of R ^23's are the same as or different from each other.
When h is 2 or more, a plurality of R ^24's are the same or different from each other.
At least one of A ³ and A ⁴ is a substituent represented by the following general formula (2a), and the other is a substituent represented by the following general formula (2b). )

(In the general formula (2a), Ar represents a substituted or unsubstituted triphenylenylene group.)

(In the general formula ^{(2b), X 4, X} 5, X 6, X 7 and ^{X 8} are each independently, .R ^Y indicating the CR ^Y or N,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Y are the same as or different from each other. )

  According to one aspect of the present invention, there is provided a material for an organic electroluminescence device, which contains the composition according to the above-described one aspect of the present invention.

  According to one aspect of the invention, there is provided a composition film comprising the composition according to one aspect of the invention.

  According to one aspect of the present invention, an anode, a cathode, and an organic layer included between the anode and the cathode, the organic layer, the composition according to one aspect of the present invention described above. There is provided an organic electroluminescent device including:

  According to one aspect of the present invention, there is provided an electronic device in which the organic electroluminescence element according to the above-described one aspect of the present invention is mounted.

  According to one aspect of the present invention, there is provided a composition capable of stably depositing a ratio of materials from one deposition source while maintaining the performance of an organic electroluminescence device, and an organic material containing the composition. Provided are a material for an electroluminescent element, a composition film containing the composition, an organic electroluminescent element containing the composition, and an electronic device including the organic electroluminescent element. be able to.

It is a figure which shows schematic structure of an example of the organic electroluminescent element which concerns on one Embodiment.

[First embodiment]
(Composition)
The composition according to the present embodiment is a composition in which two or more kinds of compounds are mixed.
The composition according to the present embodiment contains at least a first compound represented by the following general formula (1) and a second compound represented by the following general formula (2).

  The form of the composition according to the present embodiment is not particularly limited. Examples of the form of the composition according to the present embodiment include solid, powder, solution, and film. When the composition according to the present embodiment is solid, it may be formed into a pellet shape.

(First compound)
The first compound is represented by the following general formula (1).

(In the general formula (1),
R ^{1 to} R ⁴ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 24 ring carbon atoms, or a cyano group.
a is 0, 1, 2, 3, or 4.
b is 0, 1, 2, or 3.
c is 0, 1, 2, or 3.
d is 0, 1, 2, 3 or 4.
When a is 2 or more, a plurality of R ^1's are the same or different from each other.
When b is 2 or more, plural R ² are the same or different from each other.
When c is 2 or more, a plurality of R ^3's are the same as or different from each other.
When d is 2 or more, a plurality of R ^4's are the same as or different from each other.
A ¹ and A ² are each independently
A substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heterocyclic group having 6 to 30 ring-forming atoms is shown.
However, six ring structures represented by the following general formula (1a) are contained in total in R ^{1 to} R ⁴ , A ¹ and A ² . )

(In the general formula (1a), X ¹ , X ² and X ³ each independently represent CR ^X or N. At least one of the six ring structures represented by the general formula (1a). In the ring structure of, at least one of X ¹ , X ² and X ³ represents N. In the case where the ring structures represented by the general formula (1a) are bonded to each other to form a condensed ring. There are cases where it does not.
R ^X , R ^X1 , R ^X2, and R ^X3 are each independently
Single bond,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
When there are a plurality of R ^x , the plurality of R ^x are the same or different from each other.
At least one of R ^X1 , R ^X2 , R ^X3 and one or more R ^X is a single bond. )

In the present specification, “R ^{1 to} R ⁴ , A ¹ and A ² include a total of 6 ring structures represented by the general formula (1a)” means R ^{1 to} R ^4. , A ¹ and A ² include six 6-membered rings represented by the general formula (1a). The six 6-membered rings represented by the general formula (1a) are the same or different from each other.
In addition, when the ring structures represented by the general formula (1a) are bonded to each other to form a condensed ring, R ^{1 to} R ⁴ , A including the number of 6-membered rings constituting the condensed ring are included. It means that 6 and 6-membered rings are contained in ¹ and A ² . In this case, for example, when the ring structures represented by the general formula (1a) are bonded to each other to form a condensed ring represented by the following general formula (1b), the condensed ring contains two 6-membered rings. Will be out.

(In the general formula (1b),
X ^A is CR ¹⁰¹ R ¹⁰² , NR ¹⁰³ , an oxygen atom, or a sulfur atom.
R ^{101 to} R ¹⁰³ are each independently
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms is shown.
Y ^{1 to} Y ⁸ each independently represent CR ^X or N,
R ^X is
Single bond,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
When there are a plurality of R ^x , a plurality of R ^x are the same as or different from each other,
At least one of the plurality of R ^X is a single bond. )

  The first compound is preferably a compound represented by the following general formula (3).

(In the general formula (3),
R ^{1 to} R ⁶ are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
a is 0, 1, 2, 3, or 4.
b is 0, 1, 2, or 3.
c is 0, 1, 2, or 3.
d is 0, 1, 2, 3 or 4.
i is 0, 1, 2, 3, or 4.
j is 0, 1, 2, 3, 4, or 5.
When a is 2 or more, a plurality of R ^1's are the same or different from each other.
When b is 2 or more, plural R ² are the same or different from each other.
When c is 2 or more, a plurality of R ^3's are the same as or different from each other.
When d is 2 or more, a plurality of R ^4's are the same as or different from each other.
When i is 2 or more, a plurality of R ^5's are the same as or different from each other.
When j is 2 or more, a plurality of R ⁶ are the same or different from each other.
B ¹ represents a substituent represented by the following general formula (4) or the following general formula (5). )

(In the general formula (4) and the general formula (5),
X ^{1 to} X ³ represent CR ^Z or a nitrogen atom.
R ^Z is
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Z are the same or different from each other.
R ^{7 to} R ⁹ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A cyano group is shown.
k is 0, 1, 2, 3, 4, or 5.
l is 0, 1, 2, 3, 4, or 5.
m is 0, 1, 2, 3, or 4.
When k is 2 or more, a plurality of R ^7's are the same as or different from each other.
When 1 is 2 or more, a plurality of R ^8's are the same or different from each other.
When m is 2 or more, a plurality of R ^9's are the same or different from each other. )

  The first compound is preferably a compound represented by the following general formula (6).

(In the general formula (6),
R ^{1 to} R ⁶ and R ¹⁰ are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
a is 0, 1, 2, 3, or 4.
b is 0, 1, 2, or 3.
c is 0, 1, 2, or 3.
d is 0, 1, 2, 3 or 4.
i is 0, 1, 2, or 3.
j is 0, 1, 2, 3, 4, or 5.
n is 0, 1, 2, 3, 4, or 5.
When a is 2 or more, a plurality of R ^1's are the same or different from each other.
When b is 2 or more, plural R ² are the same or different from each other.
When c is 2 or more, a plurality of R ^3's are the same as or different from each other.
When d is 2 or more, a plurality of R ^4's are the same as or different from each other.
When i is 2 or more, a plurality of R ^5's are the same as or different from each other.
When j is 2 or more, a plurality of R ⁶ are the same or different from each other.
When n is 2 or more, a plurality of R ^10's are the same as or different from each other.
B ² represents a substituent represented by the following general formula (7). )

(In the general formula (7),
X ^{1 to} X ³ represent CR ^Z or a nitrogen atom.
R ^Z is
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Z are the same or different from each other.
R ¹¹ and R ¹² are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
o is 0, 1, 2, 3, 4, or 5.
p is 0, 1, 2, 3, 4, or 5.
When o is 2 or more, plural R ¹¹ are the same or different from each other.
When p is 2 or more, a plurality of R ^12's are the same as or different from each other. )

It is preferable that X ¹ , X ² , and X ³ in at least one of the six ring structures represented by the general formula (1a) are nitrogen atoms.

  In the first compound, a, b, c, d, k, l, m, n, o and p are preferably 0.

  Examples of the first compound according to this embodiment are shown below. The first compound in the present invention is not limited to these specific examples.

(Second compound)
The second compound is represented by the following general formula (2).

(In the general formula (2), R ^{21 to} R ²⁴ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 30 ring carbon atoms, or a cyano group.
e is 0, 1, 2, 3, or 4.
f is 0, 1, 2, or 3.
g is 0, 1, 2, or 3.
h is 0, 1, 2, 3, or 4.
When e is 2 or more, a plurality of R ^21's are the same as or different from each other.
When f is 2 or more, a plurality of R ^22's are the same as or different from each other.
When g is 2 or more, a plurality of R ^23's are the same as or different from each other.
When h is 2 or more, a plurality of R ^24's are the same or different from each other.
At least one of A ³ and A ⁴ is a substituent represented by the following general formula (2a), and the other is a substituent represented by the following general formula (2b). )

(In the general formula (2a), Ar represents a substituted or unsubstituted triphenylenylene group.)

(In the general formula ^{(2b), X 4, X} 5, X 6, X 7 and ^{X 8} are each independently, .R ^Y indicating the CR ^Y or N,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Y are the same as or different from each other. )

  The second compound is preferably a compound represented by the following general formula (8).

(In the general formula (8), R ^{21 to} R ²⁴ are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 24 ring carbon atoms, or a cyano group.
e is 0, 1, 2, 3, or 4.
f is 0, 1, 2, or 3.
g is 0, 1, 2, or 3.
h is 0, 1, 2, 3, or 4.
When e is 2 or more, a plurality of R ^21's are the same as or different from each other.
When f is 2 or more, a plurality of R ^22's are the same as or different from each other.
When g is 2 or more, a plurality of R ^23's are the same as or different from each other.
When h is 2 or more, a plurality of R ^24's are the same or different from each other.
At least one of A ³ and A ⁴ is a substituent represented by the following general formula (2a), and the other is a substituent represented by (2b). )

(In the general formula (2a), Ar represents a substituted or unsubstituted triphenylenylene group.)

(In the general formula ^{(2b), X 4, X} 5, X 6, X 7 and ^{X 8} are each independently, .R ^Y indicating the CR ^Y or N,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Y are the same as or different from each other. )

In a second ^{compound, X 4, X 5, X} 6, X 7 and ^{X 8} is a CR ^{Y, R Y} is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms A substituted or unsubstituted ring-forming cycloalkyl group having 3 to 25 carbon atoms, a silyl group substituted by an alkyl group having 1 to 25 carbon atoms, or a cyano group, and a plurality of R ^{Y s} are the same as each other? , Or preferably different.

In a second ^{compound, X 4, X 5, X} 6, X 7 and ^{X 8} is a CR ^{Y, R Y} is also preferably a hydrogen atom.

  In the second compound, Ar is preferably an unsubstituted divalent triphenylenylene group.

  Examples of the first compound according to this embodiment are shown below. The first compound in the present invention is not limited to these specific examples.

  Since the composition of the present embodiment contains the first compound and the second compound in combination, the composition of the present embodiment maintains one performance while maintaining the performance of the organic electroluminescence device. The ratio of materials can be stably evaporated from the evaporation source.

(Compounding ratio)
In one embodiment of the present invention, the compounding ratio of the first compound and the second compound is not particularly limited. The compounding ratio of the first compound and the second compound may be appropriately determined depending on the effect desired for the composition. The compounding ratio (mass ratio) of the compound represented by the first compound: second compound is usually within the range of 1:99 to 99: 1, and preferably within the range of 10:90 to 90:10. .

(Material for organic electroluminescence element)
The material for organic electroluminescence elements according to this embodiment includes the composition according to this embodiment. That is, the material for an organic electroluminescence device according to this embodiment contains the first compound and the second compound.
The material for organic electroluminescence elements according to this embodiment may further contain other compounds. When the organic electroluminescence element material according to the present embodiment further contains another compound, the other compound may be solid or liquid.

(Composition film)
The composition film according to the present embodiment contains the composition according to the present embodiment. That is, the film containing the composition according to the present embodiment (composition film) means a film containing the first compound and the second compound.
The composition film according to the present embodiment may further contain other compounds.
The method for forming the composition film according to the present embodiment is not particularly limited, except where it is mentioned in this specification that the method is particularly limited. As a method of forming the composition film, known methods such as a dry film forming method and a wet film forming method can be adopted. Examples of the dry film forming method include a vacuum vapor deposition method, a sputtering method, a plasma method, an ion plating method and the like. Examples of the wet film forming method include a spin coating method, a dipping method, a flow coating method, and an inkjet method.

(Device configuration of organic EL device)
The organic EL element according to this embodiment includes an organic layer between a pair of electrodes. The organic layer includes at least one layer composed of an organic compound. Alternatively, this organic layer is formed by stacking a plurality of layers made of an organic compound. The organic layer may further contain an inorganic compound. In the organic EL device of this embodiment, at least one of the organic layers is a light emitting layer. Therefore, the organic layer may be composed of, for example, one light emitting layer, or may include a layer that can be adopted in an organic EL element. The layer that can be adopted in the organic EL element is not particularly limited, but for example, at least one selected from the group consisting of a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, and a barrier layer. Layers.

  In the present embodiment, the organic layer is composed of a plurality of layers, and the composition according to the present embodiment is preferably contained in one or more layers of the plurality of layers.

By using the composition according to the present embodiment in any one or more layers of the organic EL device according to the present embodiment, high organic EL performance (e.g., driving voltage, light emission efficiency, and / or lifetime light emission performance) is obtained. ) Can be obtained. Furthermore, when the composition according to the present embodiment is formed by using the method according to the present embodiment (for example, a vacuum vapor deposition method), the first compound and the second compound in the light emitting layer are added from the initial vapor deposition to the final vapor deposition. The material ratio with the compound is stable. As a result, the organic EL element can also stably maintain high light emission performance regardless of the vapor deposition time.
In the organic EL device according to this embodiment, it is preferable that the light emitting layer contains the composition according to this embodiment.

In this embodiment, it is preferable that a hole transport layer is further provided between the anode and the light emitting layer.
In this embodiment, it is preferable that an electron transport layer is further provided between the cathode and the light emitting layer.
As another embodiment, it is also preferable that the composition according to one embodiment of the present invention is used in the electron transport zone.

As typical element configurations of the organic EL element, for example, the following configurations (a) to (f) can be mentioned.
(A) Anode / light emitting layer / cathode (b) Anode / hole injection / transport layer / light emitting layer / cathode (c) Anode / light emitting layer / electron injection / transport layer / cathode (d) Anode / hole injection / transport Layer / Light-Emitting Layer / Electron Injection / Transport Layer / Cathode (e) Anode / Hole Injection / Transport Layer / Light-Emitting Layer / Barrier Layer / Electron Injection / Transport Layer / Cathode (f) Anode / Hole Injection / Transport Layer / Barrier Layer / light emitting layer / barrier layer / electron injection / transport layer / cathode Among the above, the configuration (d) is preferably used. However, the present invention is not limited to these configurations. The "light emitting layer" is an organic layer having a light emitting function. The “hole injection / transport layer” means “at least one of a hole injection layer and a hole transport layer”. The “electron injection / transport layer” means “at least one of an electron injection layer and an electron transport layer”. When the organic EL element has a hole injection layer and a hole transport layer, it is preferable that the hole injection layer is provided between the hole transport layer and the anode. Further, when the organic EL element has an electron injection layer and an electron transport layer, it is preferable that the electron injection layer is provided between the electron transport layer and the cathode. Further, each of the hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer may be composed of one layer or a plurality of layers.

FIG. 1 shows a schematic configuration of an example of the organic EL element according to the present embodiment.
The organic EL element 1 has a transparent substrate 2, an anode 3, a cathode 4, and an organic layer 10 arranged between the anode 3 and the cathode 4. The organic layer 10 includes a hole injection layer 6, a hole transport layer 7, a light emitting layer 5, an electron transport layer 8, and an electron injection layer 9. In the organic layer 10, a hole injection layer 6, a hole transport layer 7, a light emitting layer 5, an electron transport layer 8 and an electron injection layer 9 are stacked in this order from the anode 3 side.

(Light emitting layer)
The light emitting layer 5 of the organic EL element 1 contains the composition according to the present embodiment. That is, the light emitting layer 5 includes the first compound and the second compound.

  According to the organic EL element of the present embodiment, the organic EL element is driven at a low voltage by using the first compound and the second compound in combination in the organic layer. From the viewpoint of driving the organic EL device at a low voltage, a mode in which the first compound and the second compound are contained in one light emitting layer is preferable.

(Compounding ratio)
In one embodiment of the present invention, the compounding ratio of the first compound and the second compound is not particularly limited. The compounding ratio of the first compound and the second compound may be appropriately determined according to the effect desired for the organic EL device. The compounding ratio (mass ratio) of the compound represented by the first compound: second compound is usually within the range of 1:99 to 99: 1, and preferably within the range of 10:90 to 90:10. .

(Light emitting material)
In the organic EL device according to one aspect of the present invention, the light emitting layer preferably further contains a light emitting material.
In one embodiment of the present invention, the light emitting layer preferably contains a phosphorescent light emitting material as a light emitting material. The phosphorescent material is preferably an orthometallated complex of any metal atom selected from the group consisting of iridium (Ir), osmium (Os), and platinum (Pt). Suitable phosphorescent materials will be described later.

(Layer forming method)
The method for forming each layer of the organic EL element according to one embodiment of the present invention is not particularly limited, unless otherwise specified in this specification. As a method for forming each layer, known methods such as a dry film forming method and a wet film forming method can be adopted. Examples of the dry film forming method include a vacuum vapor deposition method, a sputtering method, a plasma method, an ion plating method and the like. Examples of the wet film forming method include a spin coating method, a dipping method, a flow coating method and an inkjet method.

(Film thickness)
The film thickness of each layer of the organic EL device according to one aspect of the present invention is not limited to those mentioned above. The film thickness of each layer needs to be set to an appropriate film thickness. If the film thickness is too thick, a large applied voltage is required to obtain a constant light output, and the efficiency may deteriorate. If the film thickness is too thin, pinholes and the like may occur, and sufficient light emission brightness may not be obtained even when an electric field is applied. Usually, the film thickness is preferably in the range of 5 nm to 10 μm, more preferably 10 nm to 0.2 μm.

Hereinafter, materials and the like of constituent elements of the organic EL element will be described.
(substrate)
The substrate is used as a support for the light emitting device. As the substrate, for example, glass, quartz, plastic or the like can be used. Alternatively, a flexible substrate may be used. The flexible substrate is a substrate that can be bent (flexible), and examples thereof include a plastic substrate made of polycarbonate or polyvinyl chloride.

(anode)
For the anode formed on the substrate, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a high work function (specifically, 4.0 eV or more). Specifically, for example, indium oxide-tin oxide (ITO: indium tin oxide), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, tungsten oxide, and indium oxide containing zinc oxide. , Graphene, and the like. In addition, gold (Au), platinum (Pt), or a nitride of a metal material (for example, titanium nitride) or the like can be used.

(Hole injection layer)
The hole injection layer is a layer provided to efficiently inject holes from the anode into the organic layer. Materials used for the hole injection layer include molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, and silver oxide. Compounds, tungsten oxides, manganese oxides, aromatic amine compounds, acceptor compounds, or polymer compounds (oligomers, dendrimers, polymers, etc.) can also be used.
Among them, the substance used in the hole injection layer is preferably an aromatic amine derivative or an acceptor compound, and more preferably an acceptor compound. As the acceptor compound, an electron-withdrawing group-substituted heterocyclic derivative, an electron-withdrawing group-substituted quinone derivative, an arylborane derivative, or a heteroarylborane derivative is preferably used, and among them, hexacyanohexaazatriphenylene, F ₄ TCNQ (2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane), or 1,2,3-tris [(cyano) (4-cyano-2,3 , 5,6-Tetrafluorophenyl) methylene] cyclopropane and the like are preferably used.
The layer containing an acceptor compound is preferably in the form of further containing a matrix material. A wide variety of organic EL materials can be used as the matrix material. As the matrix material used together with the acceptor compound, a donor compound is preferably used, and an aromatic amine compound is more preferably used.

(Hole transport layer)
The hole-transporting layer is a layer containing a substance having a high hole-transporting property. An aromatic amine compound, a carbazole derivative, an anthracene derivative or the like can be used for the hole transport layer. A high molecular compound such as poly (N-vinylcarbazole) (abbreviation: PVK) or poly (4-vinyltriphenylamine) (abbreviation: PVTPA) can also be used. However, any substance other than these substances may be used as long as it has a property of transporting more holes than electrons. Note that the layer containing a substance having a high hole-transporting property is not limited to a single layer and may be a stack of two or more layers containing any of the above substances. The hole transport material is preferably a compound represented by the following general formula (H).

In the general formula (H), Ar _{1 to} Ar ₃ are each independently a substituted or unsubstituted aryl group having 6 to 50 ring-forming carbon atoms or a substituted or unsubstituted heterocycle having 5 to 50 ring-forming atoms. A group or a group constituted by a combination of a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group is shown. As the aryl group, a phenyl group, a biphenyl group, a terphenyl group, a fluorenyl group, a spirobifluorenyl group, an indenofluorenyl group, a naphthyl group, a phenanthryl group, an anthryl group, a substituent such as triphenylenyl group is preferable, As the heterocyclic group, a dibenzofuranyl group, a dibenzothiophenyl group, a carbazolyl group and the like are preferable. As the group composed of a combination of an aryl group and a heterocyclic group, a dibenzofuran-substituted aryl group, a dibenzothiophene-substituted aryl group, a carbazole-substituted aryl group and the like are preferable. These substituents may further have a substituent, and preferable substituents are as described below.
As one preferable embodiment, at least one of Ar _{1 to} Ar _{3 in} the general formula (H) is preferably a compound further substituted with an arylamino group, and is a diamine derivative, a triamine derivative, or a tetraamine derivative. Is also preferable. As the diamine derivative, a tetraaryl-substituted benzidine derivative, and TPTE (4,4′-bis [N-phenyl-N- [4′-diphenylamino-1,1′-biphenyl-4-yl] amino] -1,1 '-Biphenyl] and the like are preferably used.
The hole transport material used for the layer in contact with the phosphorescent emitting layer preferably has a high triplet level, and Ar _{1 to} Ar ₃ in the general formula (H) are each a fluorenyl group, a spirofluorenyl group or a phenyl group. A group formed by a substituent such as a biphenyl group, a phenanthryl group, a triphenylenyl group, a dibenzofuranyl group, a dibenzothiophenyl group, and a combination thereof.

(Light emitting layer)
The light emitting layer is a layer containing a substance having a high light emitting property, and various materials can be used. The light emitting layer usually contains a light emitting material (dopant material) having a high light emitting property and a host material for making it efficiently emit light. For example, as the substance having a high light emitting property, a fluorescent compound that emits fluorescence or a phosphorescent compound that emits phosphorescence can be used. A fluorescent compound is a compound capable of emitting light from a singlet excited state, and a phosphorescent compound is a compound capable of emitting light from a triplet excited state. A light emitting layer containing a fluorescent compound is called a fluorescent light emitting layer, and a light emitting layer containing a phosphorescent compound is called a phosphorescent light emitting layer.

  A wide variety of fluorescent compounds can be used as the dopant material for the fluorescent layer. Among them, the condensed polycyclic aromatic derivative, the styrylamine derivative, the condensed ring amine derivative, the boron-containing compound, the pyrrole derivative, the indole derivative, the carbazole derivative and the like are preferable as the dopant material of the fluorescence emitting layer. More preferable examples of the dopant material for the fluorescent emitting layer include a fused ring amine derivative and a boron-containing compound. Examples of the condensed ring amine derivative include a diaminopyrene derivative, a diaminochrysene derivative, a diaminoanthracene derivative, a diaminofluorene derivative, and a diaminofluorene derivative in which one or more benzofuro skeletons are condensed. Examples of the boron-containing compound include a pyrromethene derivative and a triphenylborane derivative. Here, the term “derivative” is a word indicating a compound containing the skeleton as a partial structure, and also includes a compound forming a further condensed ring and a compound forming a ring with substituents. For example, in the case of a condensed polycyclic aromatic derivative, it is a compound containing a condensed polycyclic aromatic skeleton as a partial structure, a compound which further forms a condensed ring in the condensed polycyclic aromatic skeleton, and the condensed polycyclic aromatic It also contains a compound in which the skeleton substituents form a ring.

  As the host material used for the fluorescent light emitting layer, a general fluorescent material can be used. Among them, the host material used for the fluorescent emitting layer is preferably a compound having a condensed polycyclic aromatic derivative as a main skeleton, and particularly preferably, anthracene derivative, pyrene derivative, chrysene derivative, naphthacene derivative and the like. . Particularly suitable hosts as a blue host material (a host material used together with a blue fluorescent emitting dopant material) and a green host material (a host material used together with a green fluorescent emitting dopant material) are represented by the following general formula (X). It is an represented anthracene derivative.

In the general formula (X), Ar _X1 and Ar _X2 each independently represent a substituted or unsubstituted aryl group having 6 to 50 ring-forming carbon atoms, or a substituted or unsubstituted 3 to 50 ring-forming atoms. Indicates a heterocyclic group. It is preferable that Ar _X1 and Ar _X2 each independently represent a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a heterocyclic group having 5 to 30 ring atoms.

A metal complex such as an iridium complex, an osmium complex, and a platinum complex is used as a phosphorescent light-emitting material (dopant material) that can be used for the phosphorescent light-emitting layer.
The phosphorescent material that is an orthometallated complex of a metal atom selected from the group consisting of iridium (Ir), osmium (Os), and platinum (Pt) may be a complex represented by the following formula (α). preferable.

In the formula (α), M represents at least one metal selected from the group consisting of osmium, iridium and platinum, and n represents the valence of the metal.
Ring A ₁ represents a substituted or unsubstituted aryl group having 6 to 24 ring forming carbon atoms or a heteroaryl group having 5 to 30 ring forming atoms, and ring A ₂ is a substituted group containing nitrogen as a hetero ring forming atom. Alternatively, it represents an unsubstituted heteroaryl group having 5 to 30 ring atoms.

Examples of the aryl group having 6 to 24 ring carbon atoms in the ring A ₁ of the formula (α) include the aryl group in the general formula (1) described above.
Examples of the heteroaryl group having 5 to 30 ring-forming atoms in the ring A ₁ and the ring A ₂ of the formula (α) include the heteroaryl group in the general formula (1) described above.
The substituents that the ring A ₁ and the ring A _{2 of the} formula (α) may have are the same as the substituents in the general formula (1) described above.
Further, the complex represented by the formula (α) is preferably a complex represented by the following formula (T) or (U).

In formula (T), M represents a metal, and ring B and ring C each independently represent an aryl group or heteroaryl group having 5 or 6 ring atoms.
Ring A-ring B represents a bond pair of an aryl group or a heteroaryl group, and is coordinated to the metal M via the nitrogen atom of ring A and the sp ² hybridized atom of ring B.
Ring A-ring C represents a bond pair of an aryl group or a heteroaryl group.
R _a , R _b and R _c are each independently a hydrogen atom, a substituted or unsubstituted _C 1 to _C 25 alkyl group, a substituted or unsubstituted _C 1 to _C 25 alkoxy group, a substituted or unsubstituted Amino group, substituted or unsubstituted alkenyl group having 2 to 25 carbon atoms, substituted or unsubstituted alkynyl group having 2 to 25 carbon atoms, substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, substituted or unsubstituted It represents any one selected from the group consisting of an aryl group having 6 to 24 ring carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, and R _a is 1 or more and 4 or less. And R _b is 1 or more and 4 or less, R _c is 1 or more and 4 or less, and the numbers of R _a , R _b, and R _c are each independent.
X _{1 to} X ₉ each independently represent a carbon atom or a nitrogen atom.
R _d and R _e are each independently a hydrogen atom, a substituted or unsubstituted C _{1 to} C 25 alkyl group, a substituted or unsubstituted C _{1 to} C 25 alkoxy group, a substituted or unsubstituted amino group, A substituted or unsubstituted alkenyl group having 2 to 25 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 25 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a substituted or unsubstituted ring-forming carbon R _c , R _d and R _e , which represent any one selected from the group consisting of an aryl group of the formula 6 to 24, and a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, and are bonded to the ring C. At least one of is not a hydrogen atom.
m represents the oxidation state of the metal M, and n is 1 or more. L'represents a monoanionic bidentate ligand.

In the formula (T), M includes osmium, iridium, platinum and the like, and iridium is preferable among them.
Examples of the aryl group having 5 or 6 ring-forming atoms represented by ring B and ring C include the aryl groups in the general formula (1) described above.
Examples of the heteroaryl group having 5 or 6 ring-forming atoms represented by ring B and ring C include the heteroaryl groups in the general formula (1) described above.
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms represented by R ₁ , R ₂ , R _a , R _b, and R _c , a substituted or unsubstituted alkoxy group having 1 to 25 carbon atoms, substituted or unsubstituted The aralkyl group having 7 to 50 carbon atoms, the substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms and the substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms, respectively. And the same groups as.
The substituted or unsubstituted alkenyl group having 2 to 25 carbon atoms and the substituted or unsubstituted alkynyl group having 2 to 25 carbon atoms represented by R ₁ , R ₂ , R _a , R _b, and R _c are, respectively, The same groups as those mentioned above can be mentioned.
Examples of the monoanionic bidentate ligand represented by L ′ include a ligand represented by the following formula (L ′).

In the formula _{(L '), X 4 ~X} 9, R a, and _{R b} are the same as _X 4 _~X 9, _{R a,} and _{R b} in Formula (T), preferable embodiments thereof are also the same.
The ligand represented by the formula (L ′) is represented by the formula (T) via a solid line extending from X ₉ to the outside of the ring B and a broken line extending from the nitrogen atom of the ring A to the outside of the ring A. Coordinate to the metal M.

In the formula (U), X represents any one selected from the group consisting of NR, oxygen atom, sulfur atom, BR, and selenium atom, and R is a hydrogen atom or a substituted or unsubstituted carbon number 1 to 25. Is an alkyl group.
R ₁ , R ₂ , R ₃ and R ₄ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 24 ring carbon atoms. R ₁ is 1 or more and 4 or less, R ₂ is 1 or more and 4 or less, and R ₃ is 1 or more and 4 or less. , R ₄ is 1 or more and 4 or less, and the numbers of R ₁ , R ₂ , R ₃ and R ₄ are independent of each other.

In formula (U), examples of the alkyl group having 1 to 25 carbon atoms represented by R, R ₁ , R ₂ , R ₃ and R ₄ include the groups described above, and the preferred embodiments are also the same.
Examples of the aryl group having 6 to 24 ring carbon atoms represented by R ₁ , R ₂ , R ₃ and R ₄ include the groups described above, and the preferred embodiments are also the same.

  The following compounds are preferable as the complex represented by the formula (T) or (U), but the complex is not particularly limited thereto.

  Further, an iridium complex represented by the following formula (β) is also preferable as the phosphorescent material.

In formula (β), A ^{1 to} A ⁸ include a carbon atom or a nitrogen atom, at least one of A ^{1 to} A ⁸ is a nitrogen atom, and ring B is bonded to ring A by a C—C bond, and iridium is used. (Ir) is attached to ring A by an Ir-C bond.
In formula (β), it is preferable that only one of A ^{1 to} A ⁸ is a nitrogen atom, and it is further preferable that only one of A ^{5 to} A ⁸ is a nitrogen atom, and A ⁵ is It is preferably a nitrogen atom. In formula (β), among A ^{1 to} A ⁴ , it is preferable that A ³ and A ⁴ are carbon atoms. In the formula (β), it is preferable that A ⁵ is a nitrogen atom, and A ^{1 to} A ⁴ and A ^{6 to} A ⁸ are carbon atoms.
A ⁶ is preferably CR (a carbon atom to which R is bonded), and R is a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms. , And combinations thereof. R is preferably a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms or a substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms.
In the formula (β), X is O, S or Se, and O is preferable.
In formula (β), R ^{1 to} R ⁴ are each independently mono-substituted, di-substituted, tri-substituted or tetra-substituted, or unsubstituted, and adjacent R ^{1 to} R ⁴ are bonded to each other. To form a ring, and R ^{1 to} R ⁴ are each independently,
hydrogen,
deuterium,
halogen,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl having 3 to 25 ring-forming carbon atoms,
A substituted or unsubstituted heteroalkyl having 2 to 25 atoms,
A substituted or unsubstituted arylalkyl having 7 to 50 carbon atoms,
A substituted or unsubstituted alkoxy having 1 to 25 carbon atoms,
A substituted or unsubstituted aryloxy having 6 to 24 ring-forming carbon atoms,
A substituted or unsubstituted amino,
Substituted silyl,
A substituted or unsubstituted alkenyl having 2 to 25 carbon atoms,
Cycloalkenyl having 3 to 25 ring carbon atoms,
Heteroalkenyl having 3 to 25 atoms,
Alkynyl having 2 to 25 carbon atoms,
Aryl having 6 to 24 ring carbon atoms,
Heteroaryl having 5 to 30 ring atoms,
Acyl,
A substituted carbonyl,
carboxylic acid,
ester,
Nitrile,
Isonitrile,
Sulfanil,
Sulfinyl,
Sulfonyl,
Selected from the group consisting of phosphino, and combinations thereof, the substituted silyl is substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 24 ring carbon atoms. And substituted carbonyl is carbonyl substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 24 ring carbon atoms. In formula (β), R ^{1 to} R ⁴ are preferably each independently selected from the group consisting of hydrogen, deuterium, alkyl having 1 to 25 carbons, and combinations thereof. At least one of R ² and R ³ is preferably an alkyl group having 1 to 25 carbon atoms, and more preferably the alkyl group is deuterated or partially deuterated.
In the formula (β), n is an integer of 1 to 3 and is preferably 1.

  Specific examples of the iridium complex represented by the formula (β) are shown below, but the invention is not limited thereto.

  As the complex represented by the formula (α), in addition to the complex represented by the formula (T) or (U), a complex represented by the following formula (V), (X), (Y) or (Z) can be used. It can also be used.

In formula (V), (X), (Y) or (Z), R ^{50 to} R ⁵⁴ are each independently a hydrogen atom or a substituent, k is an integer of 1 to 4, and l is 1 Is an integer of 4 and m is an integer of 1 to 2. M is Ir, Os, or Pt.
Examples of the substituent represented by R ^{50 to} R ⁵⁴ include the same as the above-described substituents.
Formula (V) is preferably represented by the following formula (V-1), and formula (X) is preferably represented by the following formula (X-1) or formula (X-2). In the following formulas (V-1), (X-1), and (X-2), R ⁵⁰ , k, and M are the same as R ⁵⁰ , k, and M described above.

  Specific examples of the complex represented by the formula (V), (X), (Y) or (Z) are shown below, but the complex is not particularly limited thereto.

(The host material of the light emitting layer)
The host material used for the phosphorescent-emitting layer is preferably a material having a triplet level higher than that of the phosphorescent dopant, and a general aromatic derivative, heterocyclic derivative, metal complex or other phosphorescent host material is used. You can As the host material used for the phosphorescent emitting layer, among them, aromatic derivatives and heterocyclic derivatives are preferable, and examples of the aromatic derivatives include naphthalene derivatives, triphenylene derivatives, phenanthrene derivatives, and fluoranthene derivatives. Examples thereof include indole derivatives, carbazole derivatives, pyridine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, isoquinoline derivatives, quinazoline derivatives, dibenzofuran derivatives and dibenzothienyl derivatives. Here, the derivative is defined as described above.
As one preferable form of the host material used for the phosphorescent emitting layer, there is a composition according to one embodiment of the present invention.

(Electron transport layer)
The electron-transporting layer is a layer containing a substance having a high electron-transporting property.
In order to improve the performance of the organic EL device, one or more layers can be provided between the electron transport layer and the light emitting layer. This layer is called a second electron transport layer, a hole blocking layer, a triplet block layer, or the like. In order to enhance the hole barrier property, it is preferable to use a material having a deep HOMO level. In order to improve the triplet block property, it is preferable to use a material having a high triplet level.
The electron transport layer includes a metal complex such as an aluminum complex, a beryllium complex, and a zinc complex, an imidazole derivative, a benzimidazole derivative, an azine derivative, a carbazole derivative, and a heterocyclic compound such as a phenanthroline derivative, a condensed aromatic hydrocarbon derivative, and Polymer compounds can be used. Preferred are imidazole derivatives (for example, benzimidazole derivatives, imidazopyridine derivatives, benzimidazophenanthridine derivatives), azine derivatives (for example, pyrimidine derivatives, triazine derivatives, quinoline derivatives, isoquinoline derivatives, phenanthroline derivatives, and these heterocycles are It may be substituted with a phosphine oxide-based substituent), and an aromatic hydrocarbon derivative (for example, an anthracene derivative or a fluoranthene derivative can be mentioned).
The composition according to one embodiment of the present invention can be used as one preferable form of the material contained in the electron transport layer, the hole blocking layer, or the triplet block layer.
As one preferable form, the electron transport layer has an alkali metal derivative (eg, lithium quinolinate complex) such as alkali metal (Li, Cs, etc.), alkaline earth metal (Mg, etc.), and alloys containing these. , And at least one selected from the group consisting of derivatives of alkaline earth metals. When the electron transport layer contains at least one of alkali metal, alkaline earth metal and alloys thereof, the content ratio in the electron transport layer is preferably 0.1 to 50% by mass, more preferably 0.1 to 20% by mass. % By mass, more preferably 1 to 10% by mass, and when the electron transport layer contains at least one of an alkali metal derivative and an alkaline earth metal derivative, the content ratio in the electron transport layer is preferably: The amount is 1 to 99% by mass, more preferably 10 to 90% by mass.

(Electron injection layer)
The electron-injection layer is a layer containing a substance having a high electron-injection property. The electron injection layer includes an alkali metal such as lithium (Li), lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ₂ ), lithium oxide (LiO _x ), and an alkaline earth metal. Derivatives of alkali metals (for example, lithium quinolinate complex) such as metals or alloys containing these, and derivatives of alkaline earth metals can be used.

(cathode)
For the cathode, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a low work function (specifically, 3.8 eV or less). Specific examples of such a cathode material include elements belonging to Group 1 or 2 of the periodic table of the elements, that is, alkali metals such as lithium (Li) and cesium (Cs), and alkaline earths such as magnesium (Mg). Examples thereof include rare earth metals such as group metals and alloys containing these (eg, MgAg, AlLi) and alloys containing these.

  In the present specification, the hydrogen atom includes isotopes having different neutron numbers, that is, light hydrogen (protium), deuterium (deuterium), and tritium (tritium).

  In the present specification, the ring-forming carbon number constitutes the ring itself of a compound having a structure in which atoms are bonded in a ring (for example, a monocyclic compound, a condensed ring compound, a bridge compound, a carbocyclic compound, a heterocyclic compound). Represents the number of carbon atoms in an atom. When the ring is substituted with a substituent, the carbon contained in the substituent is not included in the ring-forming carbon number. The same applies to the “number of ring-forming carbons” described below unless otherwise specified. For example, a benzene ring has 6 ring carbon atoms, a naphthalene ring has 10 ring carbon atoms, a pyridinyl group has 5 ring carbon atoms, and a furanyl group has 4 ring carbon atoms. When the benzene ring or naphthalene ring is substituted with, for example, an alkyl group, the carbon number of the alkyl group is not included in the ring-forming carbon number. When a fluorene ring is bonded to the fluorene ring as a substituent (including a spirofluorene ring), the carbon number of the fluorene ring as a substituent is not included in the number of ring-forming carbon atoms.

  In the present specification, the number of ring-forming atoms means a compound (for example, a monocyclic compound, a condensed ring compound, a bridged compound, a carbocyclic compound, a heterocyclic compound) having a structure in which atoms are cyclically bonded (for example, a monocyclic ring, a condensed ring, a ring assembly). The number of atoms constituting the ring itself of the ring compound). Atoms that do not form a ring and atoms included in the substituent when the ring is substituted with a substituent are not included in the number of ring-forming atoms. The “number of ring-forming atoms” described below is the same unless otherwise specified. For example, the pyridine ring has 6 ring-forming atoms, the quinazoline ring has 10 ring-forming atoms, and the furan ring has 5 ring-forming atoms. Hydrogen atoms bonded to carbon atoms of a pyridine ring or a quinazoline ring or atoms constituting a substituent are not included in the number of ring-forming atoms. When a fluorene ring is bonded to the fluorene ring as a substituent (including a spirofluorene ring), the number of atoms of the fluorene ring as a substituent is not included in the number of ring-forming atoms.

  In the present specification, “carbon number XX to YY” in the expression “substituted or unsubstituted ZZ group having XX to YY carbon atoms” represents the number of carbon atoms in the case where the ZZ group is unsubstituted. If present, the carbon number of the substituent is not included.

  In the present specification, “atom number XX to YY” in the expression “substituted or unsubstituted ZZ group having XX to YY atoms” represents the number of atoms when the ZZ group is unsubstituted, and The number of atoms of the substituent when it is included is not included.

  In the present specification, the term “unsubstituted” in the case of “substituted or unsubstituted” means that a hydrogen atom is bonded, not substituted by the above-mentioned substituent.

  Specific examples of each group in the formulas in the present specification and the substituents in the above-mentioned "substituted or unsubstituted" will be described.

  Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, pentyl group (including isomer group), hexyl group. Group (including isomer group), heptyl group (including isomer group), octyl group (including isomer group), nonyl group (including isomer group), decyl group (including isomer group), undecyl A group (including an isomer group), a dodecyl group (including an isomer group) and the like can be mentioned. Among these, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, a t-butyl group and a pentyl group (all of which include isomer groups) are preferable, Methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group and t-butyl group are more preferable, and methyl group, ethyl group, isopropyl group and t-butyl group are particularly preferable. preferable.

  The alkyl group has 1 to 25 carbon atoms, and preferably 1 to 10 carbon atoms.

Examples of the halogenated alkyl group in which the alkyl group is substituted with a halogen atom include groups in which the alkyl group having 1 to 25 carbon atoms is substituted with one or more halogen atoms, preferably a fluorine atom.
As the halogenated alkyl group having 1 to 25 carbon atoms in the present specification, specifically, a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a fluoroethyl group, a trifluoromethylmethyl group, a trifluoroethyl group, A pentafluoroethyl group etc. are mentioned.

  The alkenyl group is a group having a double bond in the alkyl group, and the alkenyl group has 2 to 25 carbon atoms, preferably 2 to 10 carbon atoms. More preferably, it is a vinyl group.

  The alkynyl group is a group having a triple bond in the above alkyl group, and the alkynyl group has 2 to 25 carbon atoms, and preferably 2 to 10 carbon atoms. More preferably, it is an ethynyl group.

Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group and an adamantyl group. Of these, a cyclopentyl group and a cyclohexyl group are preferable.
The cycloalkyl group has 3 to 25 ring carbon atoms, preferably 3 to 10 carbon atoms, more preferably 3 to 8 carbon atoms, and further preferably 3 to 6 carbon atoms.

The alkoxy group is a group represented by —OY ¹⁰ , and examples of Y ¹⁰ include the same groups as those mentioned as the alkyl group and the cycloalkyl group. The carbon number of the alkoxy group is preferably 1 to 25, more preferably 1 to 10.

The alkylthio group is a group represented by —SY ¹⁰ , and examples of Y ¹⁰ include the same groups as those mentioned as the alkyl group and the cycloalkyl group.
The alkylthio group has 1 to 25 carbon atoms, and preferably 1 to 10 carbon atoms.

  Examples of the halogen atom include fluorine, chlorine, bromine, iodine and the like, and a fluorine atom is preferable.

Examples of the aryl group include phenyl group, biphenylyl group, terphenylyl group, naphthyl group, acenaphthylenyl group, anthryl group, benzoanthryl group, aceanthryl group, phenanthryl group, benzo [c] phenanthryl group, phenalenyl group, fluorenyl group, Picenyl group, pentaphenyl group, pyrenyl group, chrysenyl group, benzo [g] chrysenyl group, s-indacenyl group, as-indacenyl group, fluoranthenyl group, benzo [k] fluoranthenyl group, triphenylenyl group, benzo [b ] A triphenylenyl group, a perylenyl group, etc. are mentioned. Among these, a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, a phenanthryl group, a triphenylenyl group, a fluoranthenyl group and a fluorenyl group are preferable, a phenyl group, a biphenylyl group and a terphenylyl group are more preferable, and a phenyl group is further preferable.
The aryl group has 6 to 30 ring carbon atoms, preferably 6 to 24 ring carbon atoms, more preferably 6 to 20 ring carbon atoms, and further preferably 6 to 18 ring carbon atoms.

The arylene group is a divalent group Y ^{21 obtained} by removing one hydrogen atom or a substituent from the aryl group.

Aralkyl groups ^is expressed as -Y 11 ^{-Y 20.} An example of Y ¹¹ is a divalent group (alkylene group or cycloalkylene group) in which one hydrogen atom or a substituent is further removed from those listed as the alkyl group and the cycloalkyl group. Examples of Y ²⁰ include the aryl groups described above.

The aryloxy group is represented by -OY ^20, and examples of Y ²⁰ include the same groups as those mentioned above as the aryl group.
Heteroaryloxy group is represented as ^{-OY 30,} examples of Y ³⁰ include those the same as those of the above heteroaryl groups.

The arylthio group is represented by -SY ^20, and examples of Y ²⁰ include the same groups as those mentioned above as the aryl group.
The heteroarylthio group is represented by -SY ^30, and examples of Y ³⁰ include the same groups as those mentioned above as the heteroaryl group.

Arylcarbonyloxy group is represented as ^{-O- (C = O) -Y 20} , examples of ^{Y 20} include those similar to those exemplified as the aryl group.

Substituted carbonyl group having a substituent selected from alkyl group and aryl ^{group, - (C = O) -Y} 10 or - it is expressed as (C = O) ^{-Y 20,} examples of ^{Y 10,} the alkyl group And the same as those mentioned above as the cycloalkyl group, and examples of Y ²⁰ include the same as those mentioned above as the aryl group.

  The heterocyclic group includes a heterocyclic group having no aromaticity and an aromatic heterocyclic group having aromaticity (a monovalent heteroaryl group and a divalent heteroarylene group).

  Examples of the heterocyclic group having no aromaticity include ring groups containing a nitrogen atom, an oxygen atom, or a sulfur atom and having 3 to 30 ring-forming atoms, preferably 3 to 20 ring-forming atoms. Specific examples of the heterocycle having no aromaticity include aziridine, oxirane, thiirane, azetidine, oxetane, trimethylene sulfide, pyrrolidine, tetrahydrofuran, tetrahydrothiophene, piperidine, tetrahydropyran, tetrahydrothiopyran and the like.

  Examples of the heterocyclic group include a nitrogen atom, an oxygen atom, a sulfur atom, a phosphorus atom, a cyclic group containing a hetero atom such as a sulfur atom, and the ring-forming atom is selected from the group consisting of a nitrogen atom, an oxygen atom or a sulfur atom. It is preferred to contain the atom which is As the heterocyclic group, a heteroaryl group having aromaticity is preferable. Examples of the heteroaryl group are pyrrolyl group, furyl group, thienyl group, pyridyl group, imidazopyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group, oxazolyl group, thiazolyl group, pyrazolyl group, isoxazolyl group. , Isothiazolyl group, oxadiazolyl group, thiadiazolyl group, triazolyl group, tetrazolyl group, indolyl group, isoindolyl group, benzofuranyl group, isobenzofuranyl group, benzothiophenyl group, isobenzothiophenyl group, indolizinyl group, quinolidinyl group, quinolyl group , Isoquinolyl group, cinnolyl group, phthalazinyl group, quinazolinyl group, quinoxalinyl group, benzimidazolyl group, benzoxazolyl group, benzthiazolyl group, indazolyl group, benzisoxa group Ryl group, benzisothiazolyl group, dibenzofuranyl group, dibenzothiophenyl group, carbazolyl group, 9-phenylcarbazolyl group, phenanthridinyl group, acridinyl group, phenanthrolinyl group, phenazinyl group, phenothiazinyl group Group, phenoxazinyl group, xanthenyl group and the like. Among these, pyridyl group, imidazopyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, benzimidazolyl group, dibenzofuranyl group, dibenzothiophenyl group, carbazolyl group, aryl group or heterocyclic group at the 9-position Substituted carbazolyl group, phenanthrolinyl group and quinazolinyl group are preferred.

The number of ring-forming atoms of the heterocyclic group is 3 to 30, preferably 5 to 24, more preferably 5 to 18.
The heteroaryl group has 5 to 30 ring forming atoms, preferably 5 to 24, and more preferably 5 to 18.
As the ring-forming atoms other than carbon atom of the heteroaryl group, nitrogen atom, oxygen atom or sulfur atom is preferable.

The heteroarylene group is a divalent group Y ³¹ in which one hydrogen atom or a substituent is further removed from the heteroaryl group.

  Further, in the present specification, the heterocyclic group may be, for example, a group derived from a partial structure represented by the following general formulas (XY-1) to (XY-18).

In the general formula (XY-1) ~ (XY -18), X A and _{Y A} are each independently a heteroatom, an oxygen atom, a sulfur atom, a selenium atom that is a silicon atom or germanium atom, Is preferred. The partial structures represented by the general formulas (XY-1) to (XY-18) have a bond at any position to form a heterocyclic group, and the heterocyclic group has a substituent. Good.

  Further, in the present specification, the substituted or unsubstituted carbazolyl group may include, for example, a group in which a ring is further condensed to a carbazole ring as represented by the following formula. Such a group may also have a substituent. Further, the position of the bond can be changed appropriately.

Mono-substituted amino group having a substituent selected from alkyl group and aryl group represented by -NH ^{(Y 10)} or -NH ^{(Y 20), Y 10} and ^{Y 20} are as described above.
Disubstituted amino group having a substituent selected from alkyl group and aryl group ^represented by ^{_{-N (Y 10) 2, -N}} (Y 20) 2 or ^{-N (Y 10) (Y 20} ), Y 10 And Y ²⁰ are as described above. When there are two Y ¹⁰ or Y ²⁰ , they may be the same or different from each other.

Mono-substituted silyl group having a substituent selected from alkyl groups and aryl groups _are represented by -SiH 2 ^{(Y 10)} or -SiH ₂ ^{(Y 20).}
Disubstituted silyl group having a substituent selected from alkyl group and aryl ^{group, -SiH} _(Y 10) ^2, represented by -SiH ^(Y _{20) 2} or ^{-SiH (Y 10) (Y 20} ).
Trisubstituted silyl group having a substituent selected from alkyl group and aryl ^{_{group, -Si (Y 10) 3,}} -Si (Y 20) 3, -Si (Y 10) 2 (Y 20) or -Si (Y ^{10) (represented} by ^Y _{20) 2.} Y ¹⁰ and Y ²⁰ are as described above, and when a plurality of Y ¹⁰ or Y ²⁰ are present, they may be the same as or different from each other.

Substituted sulfonyl group having a substituent selected from alkyl groups and aryl groups, -S ₍₌ O) represented by 2 ^{-Y 10} or ^{_{-S (= O) 2 -Y 20}} , Y 10 and ^{Y 20} are the On the street.

Disubstituted phosphoryl group having a substituent selected from alkyl groups and aryl _{^{groups, -O-P (= O)}} (Y 10) 2, -O-P (= O) (Y 20) 2 or -O-P ^{(= O)} represented by ^{(Y 10) (Y 20)} . Y ¹⁰ and Y ²⁰ are as described above, and when two Y ¹⁰ or Y ²⁰ are present, they may be the same as or different from each other.

An alkylsulfonyloxy group having an alkyl group is represented by _{-O-S (= O) 2} (Y 10), Y 10 is as above.

An arylsulfonyloxy group having a substituent selected from aryl groups represented by _{-O-S (= O) 2} (Y 20), Y 20 is as above.

  In the present specification, examples of the substituent in the case of “substituted or unsubstituted” include an aryl group having 6 to 30 ring carbon atoms, a heteroaryl group having 5 to 30 ring atoms, and an alkyl group having 1 to 25 carbon atoms. Group (linear or branched alkyl group), cycloalkyl group having 3 to 25 ring carbon atoms, halogenated alkyl group having 1 to 25 carbon atoms, alkylsilyl group having 3 to 25 carbon atoms, and 6 ring carbon atoms To 30 arylsilyl group, C1 to C25 alkoxy group, ring forming C6 to C30 aryloxy group, ring forming C5 to C30 heteroaryloxy group, substituted amino group, C1 to C25 Alkylthio group, an arylthio group having 6 to 30 ring carbon atoms, a heteroarylthio group having 5 to 30 ring atoms, an aralkyl group having 7 to 30 carbon atoms, and a heteroaryl group having 5 to 30 carbon atoms Substituted alkyl group, alkenyl group having 2 to 30 carbon atoms, alkynyl group having 2 to 30 carbon atoms, aryl group having 6 to 30 carbon atoms or phosphoryl group substituted with heterocyclic group having 5 to 30 atoms, carbon At least one group selected from the group consisting of an aryl group having 6 to 30 or a heterocyclic group having 5 to 30 atoms, a halogen atom, a cyano group, a hydroxyl group, a nitro group, and a carboxy group. Is mentioned.

  In the present specification, examples of the substituent in the case of “substituted or unsubstituted” include an aryl group having 6 to 30 ring carbon atoms, a heteroaryl group having 5 to 30 ring atoms, and an alkyl group having 1 to 25 carbon atoms. At least one group selected from the group consisting of a group (a linear or branched alkyl group), an alkylsilyl group having 3 to 25 carbon atoms, an arylsilyl group having 6 to 30 ring carbon atoms, and a cyano group is preferable. Furthermore, the specific substituents which are preferable in the explanation of each substituent are preferable.

  In the present specification, the substituent in the case of “substituted or unsubstituted” is an aryl group having 6 to 30 ring carbon atoms, a heteroaryl group having 5 to 30 ring atoms, or an alkyl group having 1 to 25 carbon atoms. (Linear or branched alkyl group), C3-25 cycloalkyl group, C3-25 alkylsilyl group, ring-forming C6-30 arylsilyl group, C1-25 alkoxy. Group, aryloxy group having 5 to 30 carbon atoms, substituted amino group, alkylthio group having 1 to 25 carbon atoms, arylthio group having 6 to 30 ring carbon atoms, aralkyl group having 7 to 30 carbon atoms, and 2 to 30 carbon atoms Is an alkenyl group having 2 to 30 carbon atoms, a halogen atom, a cyano group, a hydroxyl group, a nitro group, and a carboxy group. It may be substituted in. Further, a plurality of these substituents may be bonded to each other to form a ring.

  In the present specification, the substituent in the case of "substituted or unsubstituted" is further substituted with a substituent having 6 to 30 ring carbon atoms, a heteroaryl group having 5 to 30 ring atoms, It is preferably at least one group selected from the group consisting of an alkyl group having 1 to 25 carbon atoms (a linear or branched alkyl group), a halogen atom, and a cyano group, and it is preferable in the description of each substituent. More preferably, it is at least one group selected from the above specific substituents.

(Electronics)
An electronic device according to one aspect of the present invention is equipped with the organic electroluminescence element according to one aspect of the present invention.
The organic electroluminescent element which is one embodiment of the present invention can be used for various electronic devices. For example, the organic electroluminescent element according to one embodiment of the present invention can be used for a flat light emitter, a backlight, a light source such as instruments, a display plate, and a marker lamp. Examples of the flat light emitter include a flat panel display of a wall-mounted TV. Examples of the backlight include backlights for copying machines, printers, liquid crystal displays and the like.
The compound of the present invention can be used not only in organic EL devices but also in the fields of electrophotographic photoreceptors, photoelectric conversion devices, solar cells, image sensors and the like.

[Modification of Embodiment]
It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, etc. within the scope of achieving the object of the present invention are included in the present invention.

  In the above embodiment, the mode in which the composition is contained in the light emitting layer has been described as an example. As another aspect, for example, an organic EL element in which the composition is contained in one of the organic layers other than the light emitting layer can be mentioned. For example, an anode, a cathode, a light emitting layer included between the anode and the cathode, and an electron transport zone included between the light emitting layer and the cathode, the electron transport zone, Aspects of the organic EL device including the composition according to the embodiment are exemplified.

For example, the light emitting layer is not limited to one layer, and a plurality of light emitting layers may be laminated. When the organic EL element has a plurality of light emitting layers, at least one light emitting layer may satisfy the conditions described in the above embodiment. For example, the other light emitting layer may be a fluorescent light emitting layer or a phosphorescent light emitting layer utilizing light emission by electronic transition from a triplet excited state to a direct ground state.
When the organic EL element has a plurality of light emitting layers, these light emitting layers may be provided adjacent to each other, or a so-called tandem type organic material in which a plurality of light emitting units are stacked with an intermediate layer interposed therebetween. It may be an EL element.

Further, for example, a barrier layer may be provided adjacent to at least one of the anode side and the cathode side of the light emitting layer. The barrier layer is preferably arranged in contact with the light emitting layer and blocks at least one of holes, electrons and excitons.
For example, when the barrier layer is arranged in contact with the cathode side of the light emitting layer, the barrier layer transports electrons, and holes reach the layer on the cathode side of the barrier layer (for example, the electron transport layer). Prevent doing. When the organic EL device includes an electron transport layer, it is preferable to include the barrier layer between the light emitting layer and the electron transport layer.
In addition, when the barrier layer is arranged in contact with the light-emitting layer on the anode side, the barrier layer transports holes, and electrons are transferred to a layer on the anode side of the barrier layer (for example, a hole-transporting layer). Prevent it from reaching. When the organic EL device includes a hole transport layer, it is preferable to include the barrier layer between the light emitting layer and the hole transport layer.
Further, a barrier layer may be provided adjacent to the light emitting layer so that the excitation energy does not leak from the light emitting layer to the peripheral layer. The excitons generated in the light emitting layer are prevented from moving to a layer on the electrode side of the barrier layer (for example, an electron transport layer or a hole transport layer).
The light emitting layer and the barrier layer are preferably joined.

  In addition, the specific structure, shape, and the like in carrying out the present invention may be other structures and the like as long as the object of the present invention can be achieved.

  Examples of the present invention will be described below. The invention is in no way limited by these examples.

<Compound>
The compounds used for producing the organic EL device are shown below.

<Synthesis example>
(Synthesis Example 1)
A synthesis example of the compound PGH-N1 is shown below.

(1) Synthesis of 3-bromo-5-chlorobenzaldehyde Under an argon atmosphere, 692 g of 3,5-dibromochlorobenzene, 1.75 L of dehydrated diether, and 5.25 L of dehydrated toluene were placed in a flask and cooled to -60 ° C. 1.6 L of a 1.6 M n-butyllithium hexane solution was added dropwise, and the mixture was stirred at -60 ° C for 1 hour. After stirring, 595 g of N, N-dimethylformamide was added dropwise, and stirring was continued at -60 ° C for 1 hour to cause reaction. After the reaction was completed, 2 L of a 1N hydrochloric acid aqueous solution was added. The reaction solution was extracted with toluene, the organic layer was washed with water, dried over magnesium sulfate and then concentrated. The residue was purified by silica gel column chromatography to obtain 745 g of 3-bromo-5-chlorobenzaldehyde. DMF is an abbreviation for N, N-dimethylformamide.

(2) Synthesis of N-[(3-bromo-5-chlorophenyl) methylene] benzenamine Under an argon atmosphere, 745 g of 3-bromo-5-chlorobenzaldehyde, 238 g of aniline, and 5 L of toluene were charged into a flask, and at 110 ° C. The heating and stirring were continued for 18 hours. After completion of the reaction, the reaction solution was cooled to room temperature and concentrated to dryness to obtain 702 g of N-[(3-bromo-5-chlorophenyl) methylene] benzenamine.

(3) Synthesis of 2- (3-bromo-5-chlorophenyl) -4,6-diphenyl-1,3,5-triazine N-[(3-Bromo-5-chlorophenyl) methylene] benzenamine 702 g, benzamidine hydrochloride A flask was charged with 746 g of salt, 10.5 L of dehydrated ethanol, and 286 g of sodium hydroxide, and stirred at 80 ° C. for 20 hours. After cooling to room temperature, the precipitated crystals were collected by filtration. The obtained crystal was recrystallized from toluene to obtain 150 g of 2- (3-bromo-5-chlorophenyl) -4,6-diphenyl-1,3,5-triazine.

(4) Synthesis of 2- (5-chlorobiphenyl-3-yl) -4,6-diphenyl-1,3,5-triazine Under an argon atmosphere, 1- (3-bromo-5-chlorophenyl) -3,5 -Diphenyl-1,3,5-triazine 8.45g, phenylboronic acid 2.68g, tetrakistriphenylphosphine palladium (0) 0.693g, 2M sodium carbonate aqueous solution 30mL, and toluene 60mL are added to the flask, and 100 degreeC. The mixture was heated and stirred for 24 hours. After cooling to room temperature, the aqueous layer was removed, the organic layer was washed with saturated saline and then dried over magnesium sulfate. The organic layer was concentrated, and the residue was purified by silica gel column chromatography to obtain 1- (5-chlorobiphenyl-3-yl) -3,5-diphenyl-1,3,5-triazine (5.50 g).

(5) Synthesis of compound PGH-N1 Under an argon atmosphere, 2- (3-bromo-5-chlorophenyl) -4,6-diphenyl-1,3,5-triazine (1.67 g), 9'-phenyl-9H, 9. 'H-2,3-bicarbazole 1.63 g, trisdibenzylideneacetone dipalladium (0) 0.073 g, tri-t-butylphosphonium tetrafluoroborate 0.092 g, t-butoxy sodium 1.15 g, and xylene 40 mL The mixture was placed in a flask and heated and stirred at 140 ° C. for 6 hours. After cooling to room temperature, the reaction solution was concentrated. The residue was purified by silica gel column chromatography to obtain 1.92 g of a yellow solid. As a result of mass spectrum analysis, the yellow solid was a target substance (compound PGH-N1), and m / e = 791 with respect to a molecular weight of 791.30.

(Synthesis Example 2)
An example of the synthesis of compound PGH-N2 is shown below.

  Under an argon atmosphere, 2- (3-bromophenyl) -4- (3-biphenyl) -6-phenyl-1,3,5-triazine 4.63 g, 9'-phenyl-9H, 9'H-2,3. -4.50 g of bicarbazole, 0.183 g of trisdibenzylideneacetonedipalladium (0), 0.116 g of tri-t-butylphosphonium tetrafluoroborate, 1.35 g of sodium t-butoxy, and 40 mL of xylene were charged into a flask, and 140 ° C. The mixture was heated and stirred for 6 hours. After cooling to room temperature, the reaction solution was concentrated. The residue was purified by recrystallization to obtain 4.23 g of a yellow solid. As a result of mass spectrum analysis, the yellow solid was a target substance (compound PGH-N2), and m / e = 791 with respect to a molecular weight of 791.30.

(Synthesis Example 3)
A synthesis example of the compound PGH-N3 is shown below.

  In the synthesis of compound PGH-N2, 2- (3′-bromobiphenyl-3-instead of 2- (3-bromophenyl) -4- (3-biphenyl) -6-phenyl-1,3,5-triazine. Iyl) -4,6-diphenyl-1,3,5-triazine was used, and the compound PGH-N3 was obtained in the same manner as in Synthesis Example 2. As a result of mass spectrum analysis, the compound obtained by this synthesis was the target compound (compound PGH-N3), and m / e was 791 with respect to a molecular weight of 791.30.

<Production of organic EL device>
An organic EL device was produced as follows.

(Example 1)
1.1 g of the compound PGH-P1 was weighed, 1.1 g of the compound PGH-N1 was weighed, and these two compounds were mixed in a mortar. After mixing, 2 g of the mixture was filled in a quartz crucible for a vacuum vapor deposition device. A part of the mixture of the compound PGH-P1 and the compound PGH-N1 in the crucible was sampled, the sample was dissolved in tetrahydrofuran, and the compound PGH was calculated from the peak area value of each component detected by HPLC (High Performance Liquid Chromatography). When the ratio between -P1 and compound PGH-N1 was measured, the mass ratio (initial ratio) was compound PGH-P1: compound PGH-N1 = 5: 5.
Crucible filled with a mixture of this compound PGH-P1 and compound PGH-N1, crucible filled with compound HAT, crucible filled with compound HT-1, crucible filled with compound HT-2, filled with compound PGD-1 The crucible, the crucible filled with the compound ET-1, and the crucible filled with Liq were set in a vacuum vapor deposition apparatus.

A 25 mm × 75 mm × 1.1 mm thick glass substrate (made by Geomatic) with an ITO transparent electrode (anode) was subjected to ultrasonic cleaning in isopropyl alcohol for 5 minutes, and then UV ozone cleaning for 30 minutes. The film thickness of ITO was 130 nm. A glass substrate with a transparent electrode line after washing was mounted on a substrate holder of a vacuum vapor deposition device, and one side was protected by a mask, and then the transparent electrode was first covered on the surface on which the transparent electrode line was formed. A HAT film having a film thickness of 10 nm was formed by vapor-depositing the compound HAT to form a hole injection layer.
Next, the compound HT-1 was vapor-deposited on the hole injection layer to form a HT-1 film having a film thickness of 110 nm to form a first hole transport layer.
Next, the compound HT-2 was vapor-deposited on the first hole transport layer to form a HT-2 film having a film thickness of 35 nm to form a second hole transport layer.
Next, a film of a mixture of the compound PGH-P1 and the compound PGH-N1 and the compound PGD-1 was co-evaporated on the second hole transport layer to form a light emitting layer having a thickness of 40 nm. The concentration of the compound PGD-1 contained in the light emitting layer was 5% by mass.
Subsequent to the film formation of the light emitting layer, the compound ET-1 and 8-quinolinolatolithium (Liq) were co-evaporated at a mass ratio of 50:50 to form an electron transport layer having a film thickness of 30 nm. .
Liq was vapor-deposited on this electron transport layer to form an electron injection layer having a film thickness of 1 nm.
Metal Al was vapor-deposited on this electron injection layer to form a metal cathode having a film thickness of 80 nm.
The organic EL element manufactured in this manner was used as an organic EL element in the initial stage of vapor deposition.

After manufacturing the organic EL device, the ITO substrate was evacuated to the outside of the chamber and the mixture of the compound PGH-P1 and the compound PGH-N1 was vapor-deposited with a mass of the material in the crucible of 0.4 g (remaining amount 20% by mass). ) Continued until. After that, the ITO substrate is returned to the chamber, the already manufactured organic EL element part is protected by a mask, and then the compound HAT is vapor-deposited so as to cover the transparent electrode on the surface on which the transparent electrode line is formed. As a result, a HAT film having a film thickness of 10 nm was formed to form a hole injection layer.
Next, the compound HT-1 was vapor-deposited on the hole injection layer to form a HT-1 film having a film thickness of 110 nm to form a first hole transport layer.
Next, the compound HT-2 was vapor-deposited on the first hole transport layer to form a HT-2 film having a film thickness of 35 nm to form a second hole transport layer.
Next, a film of a mixture of the compound PGH-P1 and the compound PGH-N1 and the compound PGD-1 was co-evaporated on the second hole transport layer to form a light emitting layer having a thickness of 40 nm. The concentration of the compound PGD-1 contained in the light emitting layer was 5% by mass.
Subsequent to the film formation of the light emitting layer, the compound ET-1 and 8-quinolinolatolithium (Liq) were co-evaporated at a mass ratio of 50:50 to form an electron transport layer having a film thickness of 30 nm. .
Liq was vapor-deposited on this electron transport layer to form an electron injection layer having a film thickness of 1 nm.
Metal Al was vapor-deposited on this electron injection layer to form a metal cathode having a film thickness of 80 nm.
The organic EL element thus produced was used as the organic EL element at the final stage of vapor deposition.
Finally, the crucible residue was taken out from the vapor deposition apparatus, the crucible residue was dissolved in tetrahydrofuran, and the ratio (residual ratio) between the compound PGH-P1 and the compound PGH-N1 was determined from the peak area value of each component detected by HPLC.

  Table 1 shows a ratio (initial ratio) of the first compound and the second compound in the initial (before vapor deposition) crucible, and a ratio of the first compound and the second compound in the crucible after vapor deposition ( Residue ratio).

(Example 2)
Example 2 was carried out in the same manner as in Example 1 except that the compound PGH-N2 was used in place of the compound PGH-N1 in the light emitting layer of Example 1.

(Example 3)
Example 3 was carried out in the same manner as in Example 1 except that the compound PGH-N3 was used in place of the compound PGH-N1 in the light emitting layer of Example 1.

(Comparative Example 1)
In Comparative Example 1, the compound PGH-C1 was used in place of the compound PGH-P1 in the light emitting layer of Example 1, and the compound PGH-C2 was used in place of the compound PGH-N1 in the light emitting layer of Example 1. The same procedure as in Example 1 was performed except that the above was performed.

  In the organic EL device at the initial stage of vapor deposition according to Example 1, the mass ratio (film ratio) of the compound PGH-P1 and the compound PGH-N1 in the light emitting layer was analyzed by HPLC. As a result, the compound PGH-P1: compound PGH- N1 = 5: 5.

  In the organic EL device at the initial stage of vapor deposition according to Example 2, the mass ratio (film ratio) of the compound PGH-P1 and the compound PGH-N2 in the light emitting layer was analyzed by HPLC. As a result, the compound PGH-P1: compound PGH- N2 = 5: 5.

  In the organic EL device at the initial stage of vapor deposition according to Example 3, the mass ratio (film ratio) of the compound PGH-P1 and the compound PGH-N3 in the light emitting layer was analyzed by HPLC. As a result, the compound PGH-P1: compound PGH- N3 = 5: 5.

  In the organic EL device in the early stage of vapor deposition according to Comparative Example 1, when the mass ratio (film ratio) of the compound PGH-C1 and the compound PGH-C2 in the light emitting layer was analyzed by HPLC, the compound PGH-C1: compound PGH- It was C2 = 8: 2.

Regarding the organic EL devices of Examples 1 to 3 (initial stage of vapor deposition), the mass ratio (film ratio) of the first compound and the second compound in the light emitting layer was the same as that in the first (before vapor deposition) crucible. The ratio was the same as the mass ratio (initial ratio) of the compound to the second compound.
On the other hand, regarding the organic EL device of Comparative Example 1 (initial stage of vapor deposition), the mass ratio (film ratio) of the first compound and the second compound in the light emitting layer was the same as that in the initial (before vapor deposition) crucible. The mass ratio (the initial ratio) between the compound (1) and the second compound was significantly different. In Comparative Example 1, the first compound and the second compound were mixed in the crucible at a mass ratio of 5: 5, but the mass ratio in the film was 8: 2, and the ratio in the light emitting layer was It was found that the film was not formed in the same amount as the material preparation ratio.

<Evaluation of organic EL device>
The following evaluations were performed on the organic EL elements at the initial stage of vapor deposition and the organic EL elements at the final stage of vapor deposition produced in Examples 1 to 3 and Comparative Example 1. Table 2 shows the evaluation results.

・ Drive voltage V
The voltage (unit: V) was measured when a current was applied between the ITO transparent electrode and the metal Al cathode so that the current density was 10 mA / cm ² .

・ External quantum efficiency EQE
The spectral radiance spectrum when a voltage was applied to the device so that the current density was 10 mA / cm ² was measured with a spectral radiance meter CS-1000 (manufactured by Konica Minolta). External quantum efficiency EQE (unit:%) was calculated from the obtained spectral radiance spectrum on the assumption that Lambertian emission was performed.

・ Life LT97
The continuous current test of direct current is performed by setting the initial current density to 10 mA / cm ² , the time at which the brightness decreases to 97% of the brightness at the start of the test is measured, and the measured time is the life LT97 ( Unit: time (hrs)).

  According to Examples 1 to 3, it was found that the variations in the element performance of the organic EL element at the beginning of vapor deposition and the organic EL element at the end of vapor deposition were smaller than those of Comparative Example 1. By using a composition containing the first compound represented by the general formula (1) and the second compound represented by the general formula (2), while maintaining the performance of the organic electroluminescence device, It has been found that the ratio of materials can be stably deposited from one deposition source.

  DESCRIPTION OF SYMBOLS 1 ... Organic EL element, 3 ... Anode, 4 ... Cathode, 5 ... Light emitting layer, 7 ... Hole transport layer, 8 ... Electron transport layer.

Claims (19)

A composition in which two or more compounds are mixed,
A composition containing at least a first compound represented by the following general formula (1) and a second compound represented by the following general formula (2).

(In the general formula (1),
R ^{1 to} R ⁴ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 24 ring carbon atoms, or a cyano group.
a is 0, 1, 2, 3, or 4.
b is 0, 1, 2, or 3.
c is 0, 1, 2, or 3.
d is 0, 1, 2, 3 or 4.
When a is 2 or more, a plurality of R ^1's are the same or different from each other.
When b is 2 or more, plural R ² are the same or different from each other.
When c is 2 or more, a plurality of R ^3's are the same as or different from each other.
When d is 2 or more, a plurality of R ^4's are the same as or different from each other.
A ¹ and A ² are each independently
A substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heterocyclic group having 6 to 30 ring-forming atoms is shown.
However, six ring structures represented by the following general formula (1a) are contained in total in R ^{1 to} R ⁴ , A ¹ and A ² . )

(In the general formula (1a), X ¹ , X ² and X ³ each independently represent CR ^X or N. At least one of the six ring structures represented by the general formula (1a). In the ring structure of, at least one of X ¹ , X ² and X ³ represents N. In the case where the ring structures represented by the general formula (1a) are bonded to each other to form a condensed ring. There are cases where it does not.
R ^X , R ^X1 , R ^X2, and R ^X3 are each independently
Single bond,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
When there are a plurality of R ^x , the plurality of R ^x are the same or different from each other.
At least one of R ^X1 , R ^X2 , R ^X3 and one or more R ^X is a single bond. )

(In the general formula (2), R ^{21 to} R ²⁴ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 30 ring carbon atoms, or a cyano group.
e is 0, 1, 2, 3, or 4.
f is 0, 1, 2, or 3.
g is 0, 1, 2, or 3.
h is 0, 1, 2, 3, or 4.
When e is 2 or more, a plurality of R ^21's are the same as or different from each other.
When f is 2 or more, a plurality of R ^22's are the same as or different from each other.
When g is 2 or more, a plurality of R ^23's are the same as or different from each other.
When h is 2 or more, a plurality of R ^24's are the same or different from each other.
At least one of A ³ and A ⁴ is a substituent represented by the following general formula (2a), and the other is a substituent represented by the following general formula (2b).

(In the general formula (2a), Ar represents a substituted or unsubstituted triphenylenylene group.)

(In the general formula ^{(2b), X 4, X} 5, X 6, X 7 and ^{X 8} are each independently, .R ^Y indicating the CR ^Y or N,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Y are the same as or different from each other. ) The composition of claim 1, wherein
The composition, wherein the first compound is a compound represented by the following general formula (3).

(In the general formula (3),
R ^{1 to} R ⁶ are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
a is 0, 1, 2, 3, or 4.
b is 0, 1, 2, or 3.
c is 0, 1, 2, or 3.
d is 0, 1, 2, 3 or 4.
i is 0, 1, 2, 3, or 4.
j is 0, 1, 2, 3, 4, or 5.
When a is 2 or more, a plurality of R ^1's are the same or different from each other.
When b is 2 or more, plural R ² are the same or different from each other.
When c is 2 or more, a plurality of R ^3's are the same as or different from each other.
When d is 2 or more, a plurality of R ^4's are the same as or different from each other.
When i is 2 or more, a plurality of R ^5's are the same as or different from each other.
When j is 2 or more, a plurality of R ⁶ are the same or different from each other.
B ¹ represents a substituent represented by the following general formula (4) or the following general formula (5). )
(In the general formula (4) and the general formula (5),
X ^{1 to} X ³ represent CR ^Z or a nitrogen atom.
R ^Z is
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Z are the same or different from each other.
R ^{7 to} R ⁹ are each independently,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A cyano group is shown.
k is 0, 1, 2, 3, 4, or 5.
l is 0, 1, 2, 3, 4, or 5.
m is 0, 1, 2, 3, or 4.
When k is 2 or more, a plurality of R ^7's are the same as or different from each other.
When 1 is 2 or more, a plurality of R ^8's are the same or different from each other.
When m is 2 or more, a plurality of R ^9's are the same or different from each other. ) The composition of claim 1, wherein
The composition, wherein the first compound is a compound represented by the following general formula (6).

(In the general formula (6),
R ^{1 to} R ⁶ and R ¹⁰ are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
a is 0, 1, 2, 3, or 4.
b is 0, 1, 2, or 3.
c is 0, 1, 2, or 3.
d is 0, 1, 2, 3 or 4.
i is 0, 1, 2, or 3.
j is 0, 1, 2, 3, 4, or 5.
n is 0, 1, 2, 3, 4, or 5.
When a is 2 or more, a plurality of R ^1's are the same or different from each other.
When b is 2 or more, plural R ² are the same or different from each other.
When c is 2 or more, a plurality of R ^3's are the same as or different from each other.
When d is 2 or more, a plurality of R ^4's are the same as or different from each other.
When i is 2 or more, a plurality of R ^5's are the same as or different from each other.
When j is 2 or more, a plurality of R ⁶ are the same or different from each other.
When n is 2 or more, a plurality of R ^10's are the same as or different from each other.
B ² represents a substituent represented by the following general formula (7). )
(In the general formula (7),
X ^{1 to} X ³ represent CR ^Z or a nitrogen atom.
R ^Z is
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Z are the same or different from each other.
R ¹¹ and R ¹² are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
o is 0, 1, 2, 3, 4, or 5.
p is 0, 1, 2, 3, 4, or 5.
When o is 2 or more, plural R ¹¹ are the same or different from each other.
When p is 2 or more, a plurality of R ^12's are the same as or different from each other. ) The composition according to any one of claims 1 to 3,
The composition wherein X ¹ , X ² , and X ³ in at least one of the six ring structures represented by the general formula (1a) are nitrogen atoms. The composition according to any one of claims 1 to 4,
A composition wherein a, b, c, d, k, l, m, n, o and p are 0. The composition according to any one of claims 1 to 5,
The composition, wherein the second compound is a compound represented by the following general formula (8).

(In the general formula (8), R ^{21 to} R ²⁴ are each independently
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms,
A substituted or unsubstituted heterocyclic group having 3 to 30 ring-forming atoms,
It represents a silyl group substituted with one or more groups selected from the group consisting of an alkyl group having 1 to 25 carbon atoms and an aryl group having 6 to 24 ring carbon atoms, or a cyano group.
e is 0, 1, 2, 3, or 4.
f is 0, 1, 2, or 3.
g is 0, 1, 2, or 3.
h is 0, 1, 2, 3, or 4.
When e is 2 or more, a plurality of R ^21's are the same as or different from each other.
When f is 2 or more, a plurality of R ^22's are the same as or different from each other.
When g is 2 or more, a plurality of R ^23's are the same as or different from each other.
When h is 2 or more, a plurality of R ^24's are the same or different from each other.
At least one of A ³ and A ⁴ is a substituent represented by the following general formula (2a), and the other is a substituent represented by (2b).

(In the general formula (2a), Ar represents a substituted or unsubstituted triphenylenylene group.)

(In the general formula ^{(2b), X 4, X} 5, X 6, X 7 and ^{X 8} are each independently, .R ^Y indicating the CR ^Y or N,
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
A silyl group substituted with an alkyl group having 1 to 25 carbon atoms or a cyano group is shown.
A plurality of R ^Y are the same as or different from each other. ) The composition according to any one of claims 1 to 6, wherein
^{X 4, X 5, X 6} , X 7 and ^{X 8} is a CR ^Y,
R ^Y is
Hydrogen atom,
Halogen atom,
A substituted or unsubstituted alkyl group having 1 to 25 carbon atoms,
A substituted or unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms,
Represents a silyl group substituted with an alkyl group having 1 to 25 carbon atoms, or a cyano group,
The plurality of R ^Y is the same as or different from each other in the composition. The composition according to any one of claims 1 to 7, wherein
A composition in which Ar is an unsubstituted divalent triphenylenylene group.   A material for an organic electroluminescence device, which comprises the composition according to any one of claims 1 to 8.   A composition film comprising the composition according to any one of claims 1 to 8. An anode, a cathode, and an organic layer contained between the anode and the cathode,
The organic layer comprises the composition according to any one of claims 1 to 8,
Organic electroluminescent device. The organic electroluminescent element according to claim 11,
The organic layer is composed of a plurality of layers,
The organic electroluminescent element, wherein the composition is contained in one layer of the plurality of layers. The organic electroluminescent element according to claim 11 or 12,
The organic layer includes a light emitting layer,
The said light emitting layer is an organic electroluminescent element containing the said composition. The organic electroluminescent element according to claim 13,
An organic electroluminescence device, wherein the light emitting layer further contains a light emitting material. The organic electroluminescent element according to claim 14,
The light emitting layer contains a phosphorescent material as the light emitting material,
The organic electroluminescence device, wherein the phosphorescent material is an orthometallated complex of any metal atom selected from the group consisting of iridium, osmium, and platinum. The organic electroluminescent element according to any one of claims 13 to 15,
An organic electroluminescence device further comprising a hole transport layer between the anode and the light emitting layer. The organic electroluminescent element according to any one of claims 13 to 16,
An organic electroluminescence device further comprising an electron transport layer between the cathode and the light emitting layer. An anode, a cathode, a light emitting layer included between the anode and the cathode, and an electron transport zone included between the light emitting layer and the cathode,
The electron transport zone comprises a composition according to any one of claims 1-8.
Organic electroluminescent device.   An electronic device equipped with the organic electroluminescence element according to claim 11.