JP2003338377A - Organic el element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL element providing high efficiency and having excellent durability and high color purity. <P>SOLUTION: This organic EL element has a structure in which at least one layer of, preferably, a positive hole injection transport layer, a light emitting layer, an electron transport layer, and an electron injection layer each are laid in layers sequentially from an anode side. The electron transport layer contains a naphthacene derivative and/or an anthracene derivative (preferably, naphthacene derivative). Preferably, the electron injection layer (having thickness of, preferably, 0.6 to 20 nm, in particular, preferably, 1 to 10 nm) contains, preferably, an organic compound (in particular, preferably, phenanthroline derivative). <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic EL (electroluminescence) device, and more particularly to a device that emits light by applying an electric field to a thin film made of an organic compound.

[0002]

2. Description of the Related Art An organic EL device has a structure in which a thin film containing a fluorescent organic compound is sandwiched between an electron injection electrode (cathode) and a hole injection electrode (anode), and electrons and holes are injected into the thin film. Are elements that generate excitons by recombining with each other and emit light by utilizing light emission (fluorescence / phosphorescence) when the excitons are deactivated.

In the organic EL element, between the electrodes,
In addition to the light emitting layer consisting of a thin film containing a fluorescent organic compound,
By optimizing the electrons or holes injected into the light emitting layer,
For the purpose of improving luminous efficiency, a layer called an electron injection layer, an electron transport layer, or an electron transport layer as an electron injection and / or transport layer, or a hole injection as a hole injection and / or transport layer. Generally, a layer called a layer, a hole transport layer, and a hole injection transport layer is provided.

Examples of electron injecting and transporting materials include metal complex compounds (see, for example, Patent Document 1) and heterocyclic compounds, and examples of the heterocyclic compound include phenanthroline compounds (see, for example, Patent Documents 2 and 3). , Indole (pyrrole) compounds (for example, refer to Patent Documents 4 to 7), quinoxaline-based compounds (for example, refer to Patent Documents 8 to 12), oxadiazole-based compounds (for example, Patent Document 1).
3 to 19), carbazole compounds (see, for example, Patent Documents 20 and 21), and examples in which a layer obtained by doping these electron injecting and transporting materials with a donor dopant or an alkali metal (see, for example, Patents). Reference 22
To 24), examples in which a hydrocarbon compound is contained in the electron transport layer (see, for example, Patent Documents 25 and 26), and the like.

An example in which two or more electron injecting and transporting layers are provided (see, for example, Patent Document 27) or an adhesion improving layer is provided between the electron injecting layer and the electron injecting cathode (for example, Patent Document 2).
8) and the like are disclosed, and in some cases, the material used for the adhesion improving layer is limited by the surface energy.

On the other hand, with respect to the light emitting layer, many methods for doping a small amount of a fluorescent dye having a high fluorescence quantum yield have been reported and disclosed as means for achieving high efficiency and long life. For example, a red light emitting device in which an organometallic complex such as tris (8-quinolinolato) aluminum (Alq3) or an arylamine, oxadiazole or carbazole derivative is doped with a perylene derivative is disclosed (for example, Patent Documents 29 and 30). reference). Further, regarding a preferable combination of a host and a dopant for obtaining a highly efficient device, an ionization potential (IP) and an electron affinity (Ea)
An example limited by is also disclosed (for example, see Patent Document 31).

However, in the above-mentioned conventional techniques, it is possible to efficiently inject electrons from the cathode by using a material having a good electron injecting property for the electron injecting and transporting layer, but a material having a high electron injecting property. Have a low carrier mobility (electron transportability). When the carrier mobility (electron transportability) of the electron transport layer is low, a strong electric field is required to move the carriers in the electron transport layer to the light emitting layer, and as a result, the driving voltage of the device is increased and the device emits light. It is a cause of lowering efficiency.

Further, in order to obtain an optically optimum external extraction efficiency, it is necessary to control the distance between the light emitting layer and the cathode. Controlling the distance between the light emitting layer and the cathode changes the film thickness of the electron transport layer. It can be done by
However, in the conventional device, since the carrier transport property of the electron transport layer is low, the change of the drive voltage is large when the film thickness of the electron transport layer is changed, and the optimization of the optical external extraction efficiency and the low voltage drive are compatible. Was difficult. Furthermore, when the carrier mobility (electron transportability) of the electron transport layer is low, the carrier concentration of the electron transport layer increases, and holes enter the electron transport layer, so that recombination of carriers in the electron transport layer occurs. In some cases, the color purity obtained when only the light emitting layer emits light cannot be obtained because the electron transport material emits light. In addition, the recombination of carriers other than the light emitting layer adversely affects the life of the device.

In addition, there are many polar molecules having a large dipole moment in a material having a high electron injecting property, and when these molecules come into contact with the light emitting layer, interaction with the light emitting material occurs and energy of excitons is lost. Can also be considered.

On the other hand, there is no material having a high electron-transporting property, which has both adhesiveness to the electron-injecting cathode and electron-injecting property. If such a material is used for the electron-injecting / transporting layer, uniform light emission cannot be obtained. In many cases.

Further, even when the functions of the electron transport layer and the electron injection layer are separated, no combination of materials has been found that optimally exhibits the respective functions, and sufficient device characteristics have not been obtained.

Further, regarding the light emitting layer, according to the conventional technique, the concentration quenching of the light emitting material can be suppressed by doping to improve the efficiency, and the combination of the host and the dopant is limited by the values of IP and Ea of those materials. As a result, carriers can be trapped in the dopant and the recombination efficiency can be improved.

However, when the carrier mobility (electron transporting property) of the host material is low, the carriers in the light emitting layer are localized in the host material and the probability of recombination on the host material molecules increases. In this case, energy transfer from the host in the excited state to the dopant is required for the dopant to emit light, and if energy transfer efficiency in that process is low, loss occurs. In addition, the hole transportability may not be balanced, and holes may penetrate into the electron transport layer, which may cause a decrease in light emission efficiency of the device. In addition, when energy transfer from the host to the dopant is insufficient, the host itself may emit light, which may deteriorate the color purity of the device.

Therefore, improvements in the above points are required.

[0015]

[Patent Document 1] JP-A-5-214333

[Patent Document 2] Japanese Unexamined Patent Publication No. 7-82551

[Patent Document 3] JP-A-5-331459

[Patent Document 4] JP-A-5-339565

[Patent Document 5] Japanese Patent Laid-Open No. 2000-91075

[Patent Document 6] Japanese Unexamined Patent Publication No. 10-237442

[Patent Document 7] Japanese Patent Laid-Open No. 2003-17271

[Patent Document 8] Japanese Patent Laid-Open No. 9-3342

[Patent Document 9] Japanese Unexamined Patent Publication No. 9-13025

[Patent Document 10] JP-A-7-102250

[Patent Document 11] JP-A-6-207169

[Patent Document 12] Japanese Unexamined Patent Publication No. 9-188874

[Patent Document 13] Japanese Patent Laid-Open No. 2000-281663

[Patent Document 14] Japanese Patent Laid-Open No. 9-104679

[Patent Document 15] JP-A-8-193075

[Patent Document 16] JP-A-8-3149

[Patent Document 17] Japanese Patent Laid-Open No. 8-3148

[Patent Document 18] JP-A-7-179394

[Patent Document 19] JP-A-6-140156

[Patent Document 20] Japanese Unexamined Patent Publication No. 8-60144

[Patent Document 21] JP-A-8-88083

[Patent Document 22] Japanese Patent No. 2926845

[Patent Document 23] Japanese Patent No. 2846503

[Patent Document 24] JP-A-4-297076

[Patent Document 25] Japanese Patent Laid-Open No. 2000-344691

[Patent Document 26] Japanese Patent Laid-Open No. 4-335087

[Patent Document 27] Japanese Patent Laid-Open No. 2000-340364

[Patent Document 28] JP-A-6-330034

[Patent Document 29] Japanese Patent Laid-Open No. 10-330295

[Patent Document 30] Japanese Patent Laid-Open No. 11-233261

[Patent Document 31] Japanese Patent No. 3069139

[0016]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic EL device having high efficiency, excellent durability and high color purity.

[0017]

The above object can be achieved by the present invention described below. (1) In an organic EL device having a structure in which at least one light emitting layer, an electron transport layer, and an electron injection layer are sequentially stacked from the anode side, the electron transport layer contains a naphthacene derivative and / or anthracene derivative. Organic EL element that does. (2) The organic EL device according to (1), which has at least one hole injecting and transporting layer on the anode side of the light emitting layer. (3) The above (1) in which the electron injection layer contains an organic compound.
Alternatively, the organic EL device of (2). (4) The organic EL device according to any one of (1) to (3) above, wherein the electron injection layer has a thickness of 0.6 to 20 nm. (5) The organic EL device according to (4) above, wherein the electron injection layer has a thickness of 1 to 10 nm. (6) The organic EL device according to any one of (1) to (5) above, wherein the electron injection layer contains a heterocyclic compound. (7) The organic EL device according to any one of (1) to (6), wherein the electron injection layer contains a nitrogen-containing heterocyclic compound. (8) The electron injection layer has 1,10-phenanthroline, 1,9-phenanthroline, 1,8-phenanthroline, 1,7-phenanthroline, 2,9-phenanthroline, 2,8-phenanthroline, 2,7-phenanthroline, 3 , 8-phenanthroline, 3,
The organic EL device according to any one of (1) to (7) above, which contains at least one of 7-phenanthroline, 4,7-phenanthroline and a phenanthroline derivative having one or more of these phenanthroline skeletons in the molecule. (9) The phenanthroline or phenanthroline derivative contained in the electron injection layer is represented by the following formula (1a) or formula (1)
The organic EL device of the above (8) represented by b).

[0018]

[Chemical 7]

[In the formula (1a), Y _{2 to} Y ₉ may be the same or different and each represents hydrogen, an aryl group,
An alkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkenyl group, an amino group or a heterocyclic group, which are adjacent to each other.
One or more may combine with each other to form a ring. Expression (1
In b), A and B, which may be the same or different, each represents a group represented by formula (1c), and L represents a single bond or a divalent linking group. In formula (1c), Y ₁₂ ~.
Y ₁₉ may be the same or different,
It has the same meaning as Y ₂ to Y ₉ in the formula (1a). However,
One of Y ₁₂ to Y ₁₉ in formula (1c) constitutes L, but Y ₁₂ to Y ₁₉ constituting L may be the same or different in A and B. (10) The organic EL device according to any one of (1) to (9) above, wherein the electron transport layer contains a naphthacene derivative. (11) The organic EL device according to the above (10), in which the naphthacene derivative contained in the electron transport layer is represented by the following formula (2).

[0020]

[Chemical 8]

[In the formula (2), Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ ,
^{Q 50, Q 60, Q 70} , Q 80, Q 110, Q 1 20, Q 130 and Q ¹⁴⁰ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, It represents an alkenyl group, an aralkyl group or a heterocyclic group, which may be the same or different. (12) Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ and Q in the naphthacene derivative represented by the formula (2) contained in the electron transport layer.
The organic EL device according to (11) above, wherein at least one of ⁵⁰ , Q ⁶⁰ , Q ⁷⁰ and Q ⁸⁰ is an aryl group. (13) The above (11) or (12), wherein at least one of Q ¹⁰ , Q ²⁰ , Q ³⁰ and Q ^{40 in} the naphthacene derivative represented by the formula (2) contained in the electron transport layer is an aryl group. Organic EL device. (14) The organic EL device according to any one of the above (9) to (13), in which the naphthacene derivative contained in the electron transport layer is represented by the following formula (2a).

[0022]

[Chemical 9]

[In the formula (2a), Q ^{5 to} Q ⁸ and Q ^{11 to} Q
¹⁶ is hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an alkylthio group,
It represents an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, which may be the same or different. Q ^{21 to} Q ²⁵ and Q ^{51 to} Q ⁵⁵ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, These may be the same or different, and two or more adjacent to each other may bond to each other to form a ring. (15) The organic EL device according to any one of (9) to (14), wherein the naphthacene derivative contained in the electron transport layer is a hydrocarbon compound. (16) The organic EL device according to any one of (1) to (15) above, wherein the light emitting layer contains a host material and a dopant material, and the host material contains a naphthacene derivative. (17) The organic EL device according to (16), in which the naphthacene derivative contained in the light emitting layer is represented by the following formula (2).

[0024]

[Chemical 10]

[In the formula (2), Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ ,
^{Q 50, Q 60, Q 70} , Q 80, Q 110, Q 1 20, Q 130 and Q ¹⁴⁰ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, It represents an alkenyl group, an aralkyl group or a heterocyclic group, which may be the same or different. (18) Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ and Q in the naphthacene derivative represented by the formula (2) contained in the light emitting layer.
The organic EL device of (17) above, wherein at least one of ⁵⁰ , Q ⁶⁰ , Q ⁷⁰ and Q ⁸⁰ is an aryl group. (19) Q ¹⁰ , Q ²⁰ , Q ³⁰ and Q ⁴⁰ in the naphthacene derivative represented by the formula (2) contained in the light emitting layer.
(17) wherein at least one or more of are aryl groups
Alternatively, the organic EL device of (18). (20) The naphthacene derivative contained in the host material of the light emitting layer is represented by the following formula (2a) (16) to (1)
The organic EL device according to any one of 9).

[0026]

[Chemical 11]

[In the formula (2a), Q ^{5 to} Q ⁸ and Q ^{11 to} Q
¹⁶ is hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an alkylthio group,
It represents an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, which may be the same or different. Q ^{21 to} Q ²⁵ and Q ^{51 to} Q ⁵⁵ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, These may be the same or different, and two or more adjacent to each other may bond to each other to form a ring. (21) The organic EL device according to any one of (16) to (20), wherein the naphthacene derivative contained in the light emitting layer is a hydrocarbon compound. (22) The organic EL device according to any one of (16) to (21) above, wherein the dopant material of the light emitting layer contains a fluoranthene derivative. (23) The organic EL device according to the above (22), wherein the fluoranthene derivative is an indenoperylene derivative represented by the following formula (3a).

[0028]

[Chemical 12]

[In the formula (3a), Z _{1 to} Z ₆ , Z ₉ , Z ₁₀ ,
Z _{11 to} Z ₁₆ , Z ₁₉ and Z ₂₀ are each hydrogen, halogen, alkyl group, alkoxy group, alkylthio group, alkenyl group, alkenyloxy group, alkenylthio group, aromatic ring-containing alkyl group, aromatic ring-containing alkyloxy group. , An aromatic ring-containing alkylthio group, an aromatic ring group, an aromatic ring oxy group,
Aromatic ring thio group, aromatic ring alkenyl group, alkenyl aromatic ring group, amino group, cyano group, hydroxyl group, -COOR ₁ (wherein R ₁ is hydrogen, an alkyl group, an alkenyl group, an aromatic ring-containing alkyl group or an aromatic ring group Represents), -COR ₂ (wherein R ₂ represents hydrogen, an alkyl group, an alkenyl group, an aromatic ring-containing alkyl group, an aromatic ring group or an amino group), or -OCOR ₃ (wherein R ₃ is an alkyl group). Group, an alkenyl group, an aromatic ring-containing alkyl group or an aromatic ring group), and further Z _{1 to} Z ₆ , Z ₉ , Z ₁₀ , Z _{11 to} Z ₁₆ ,
Adjacent groups in Z ₁₉ and Z ₂₀ may be bonded to each other to form a ring with the carbon atom which is substituted. ] (24) Electron Transportability μ of Electron Transport Layer Defined Below
The organic EL element of any one of the above (1) to (23), wherein _a is 80 nm / V or more (provided that the electron transporting property μ _a is the same as that of the organic EL element of the above (1). It is a parameter defined as follows by the change of the driving voltage required to pass the current of 100 mA / cm ² when changed, and the thickness (nm) of the electron transport layer is d ₁ , d ₂ (however, d
When the driving voltage (V) at 100 mA / cm ² driving when ₁ > d ₂ ) is V ₁ and V ₂ , respectively, μ _a = (d ₁ −
d ₂ ) / (V ₁ −V ₂ )). (25) The difference in the value of the ionization potential between the electron transport layer and the light emitting layer is 0.1 eV or less (1) to (24).
Any one of the organic EL elements. (26) The value of the dipole moment of the material used for the electron transport layer is 1.0 Debye or less (1) to (2)
The organic EL device according to any one of 5). (27) The light emitting layer contains a host material and a dopant material, and the value of the dipole moment of the host material is 1.0 Deby.
The organic EL device according to any one of (16) to (26), which is e or less.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The organic EL device of the present invention has an anode, and at least one layer, preferably a hole injecting and transporting layer, a light emitting layer, an electron transporting layer, and an electron injecting layer, are sequentially laminated from the anode (hole injecting electrode) side. A cathode (electron injection electrode) is provided on the electron injection layer. By thus providing the electron transport layer and the electron injection layer separately, it becomes possible to select the material having the best characteristics suitable for each layer.
Therefore, in the present invention, the electron transport layer contains a naphthacene derivative and / or an anthracene derivative, and the electron injection layer contains a material having excellent adhesion to the cathode material and the electron transport layer. The injection layer contains an organic compound.

As described above, in the present invention, a highly efficient organic compound can be obtained by defining the device structure, selecting the compound suitable as the material for the electron injection layer and the material for the electron transport layer, and selecting the combination thereof. An EL element can be obtained.
That is, with the configuration of the present invention, the electric field strength applied to the electron transport layer can be reduced, and low voltage driving can be enabled. Also,
This makes it possible to reduce the voltage change when the thickness of the electron transport layer is changed, so that the optical film thickness can be adjusted without changing the voltage in order to obtain the optimum external extraction efficiency of light emission. A highly efficient organic EL device can be obtained. Furthermore, since the carrier (electron) concentration in the electron transport layer can be lowered, penetration of holes into the electron transport layer can be prevented, and the generation of excitons in the electron transport layer can be suppressed.
Organic E of high color purity with almost no light emission from the electron transport layer
An L element is obtained. Further, for the same reason, the life of the element can be extended.

In particular, by using a nonpolar molecule having a small dipole moment as the material for the electron transport layer, the electron transport layer having a high electron transport property as described above can be obtained.

Further, by using a non-polar molecule in the electron transport layer, interaction with the light emitting material at the interface of the light emitting layer is suppressed, and it is considered that there is also an effect of preventing energy loss of excitons at the interface.

On the other hand, the light emitting layer used in combination with such an electron transport layer preferably contains a host material and a dopant material, and the naphthacene derivative preferably used as a material for the electron transport layer is used as the host material. It is preferable to use.

As described above, in the present invention, a material having a high electron transporting property is used as the host material of the light emitting layer, and a material capable of trapping electrons in the host material is used as the dopant material, whereby the light emitting layer is obtained. The electrons inside are highly localized in the trap order of the dopant, so that an organic EL device with high efficiency and high color purity can be obtained. Further, it is preferable that the host material of the light emitting layer has a small dipole moment and a high electron transporting property. That is, by using a material having a high electron transporting property as the host material of the light emitting layer and doping a compound having a higher electron affinity than the host material, the probability that carriers (electrons) in the light emitting layer are localized in the dopant molecule is The organic EL having high efficiency and color purity can be improved, and excitons of the dopant are efficiently generated and excitons of the host are less likely to be generated.
The device is obtained. Further, by using a non-polar molecule as the host material, the interaction with the dopant material can be suppressed, so that it is considered that there is also an effect of preventing a decrease in efficiency and color purity due to the interaction.

The electron transport layer in the present invention contains a naphthacene derivative (including naphthacene) and / or an anthracene derivative.

The anthracene derivative is represented by the following formula (4)
What is represented by is preferable.

[0038]

[Chemical 13]

In the formula (4), n ₁₀₁ is 1 or 2. A ₁₀₁ represents a monophenylanthryl group or a diphenylanthryl group, and when n ₁₀₁ is 2, they may be the same or different. L ₁₀₁ is hydrogen,
It represents a single bond or a divalent linking group.

The monophenylanthryl group or diphenylanthryl group represented by A ₁₀₁ may be unsubstituted or may have a substituent, and in the case of having a substituent, the substituent is an alkyl group or an aryl group. Groups, heterocyclic groups, alkoxy groups, aryloxy groups, amino groups and the like,
These substituents may be further substituted. Although these substituents will be described later, an aryl group is particularly preferable. The substitution position of such a substituent is not particularly limited, but it is preferably a phenyl group bonded to the anthracene ring, not the anthracene ring.

The bonding position of the phenyl group on the anthracene ring is preferably 9-position or 10-position on the anthracene ring.

In the formula (4), L ₁₀₁ represents hydrogen, a single bond or a divalent linking group, and the divalent linking group represented by L ₁₀₁ may have an alkylene group or the like as an arylene group. Is preferred. Such an arylene group will be described later.

Among the phenylanthracene derivatives represented by the formula (4), those represented by the formulas (4a) and (4b) are preferable.

[0044]

[Chemical 14]

[0045]

[Chemical 15]

The equation (4a) will be described.
In a), M ₁ and M ₂ each represent an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, an amino group or a heterocyclic group, and particularly preferably an aryl group.

The alkyl group represented by M ₁ and M ₂ may have a substituent, may be linear or branched, and has 1 to 10 carbon atoms, more preferably 1 carbon atom. ~
A substituted or unsubstituted alkyl group of 4 is preferred. Particularly, an unsubstituted alkyl group having 1 to 4 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, (n-, i-) propyl group, (n-, i-, s-, t-) butyl. Groups and the like.

The cycloalkyl group represented by M ₁ and M ₂ may have a substituent, and examples thereof include a cyclohexyl group and a cyclopentyl group.

The aryl group represented by M ₁ and M ₂ preferably has 6 to 20 carbon atoms, and may have a substituent such as a phenyl group and a tolyl group. Specific examples thereof include a phenyl group, (o-, m-, p-) tolyl group, pyrenyl group, naphthyl group, anthryl group, biphenyl group, phenylanthryl group, tolylanthryl group and the like.

The alkenyl group represented by M ₁ and M ₂ preferably has 6 to 50 carbon atoms in total, and may be unsubstituted or may have a substituent. It is preferable to have a substituent. At this time, the substituent is preferably an aryl group such as a phenyl group. Specific examples include a triphenyl vinyl group, a tritolyl vinyl group, a tribiphenyl vinyl group and the like.

The alkoxy group represented by M ₁ and M ₂ preferably has an alkyl moiety having 1 to 6 carbon atoms,
Specific examples include a methoxy group and an ethoxy group. The alkoxy group may be further substituted.

The aryloxy group represented by M ₁ and M ₂ may have a substituent, and examples thereof include a phenoxy group.

The amino group represented by M ₁ and M ₂ may be unsubstituted or may have a substituent, but preferably has a substituent. In this case, the substituent is an alkyl group (methyl group). Groups, ethyl groups, etc.), aryl groups (phenyl groups, etc.) and the like. Specific examples thereof include a diethylamino group, a diphenylamino group and a di (m-tolyl) amino group.

As the heterocyclic group represented by M ₁ and M ₂ ,
Examples thereof include bipyridyl group, pyrimidyl group, quinolyl group, pyridyl group, thienyl group, furyl group and oxadiazoyl group. These may have a substituent such as a methyl group and a phenyl group.

In equation (4a), q1 and q2 are
Each represents 0 or an integer of 1 to 5, particularly 0 or 1.
Is preferred. q1 and q2 are 1 to
An integer of 5, especially when 1 or 2, M ₁ and M ₂
Is preferably an aryl group.

In equation (4a), M₁ And M₂ Is the same as
Or they may be different, M ₁ And M₂ And each
When there are a number, M₁ Each other, M₂ Even though they are the same, they are different
May be M₁ Mutually or M₂ Each other
They may combine with each other to form a ring such as a benzene ring, and form a ring.
It is also preferable to do.

N has the same meaning as n _{101 in} formula (4).

In the formula (4a), L ₁₀ represents hydrogen, a single bond or an arylene group. The arylene group represented by L ₁₀ may have a substituent, but is preferably unsubstituted, and specifically, other arylene groups such as a phenylene group, a biphenylene group, and an anthrylene group can be used. ,
Examples include those in which two or more arylene groups are directly linked. As L ₁₀ , a single bond, a p-phenylene group, a 4,4′-biphenylene group and the like are preferable.

The arylene group represented by L ₁₀ may have a substituent, and two or more arylene groups have an alkylene group, —O—, —S— or —NR—.
May intervene and connect. Here, R represents an alkyl group or an aryl group. Examples of the alkyl group include a methyl group and an ethyl group, and examples of the aryl group include a phenyl group. Of these, an aryl group is preferable, and in addition to the above phenyl group, A ₁₀₁ may be used, and further, a phenyl group substituted with A ₁₀₁ may be used. Further, the alkylene group is a methylene group,
Ethylene groups and the like are preferred.

Specific examples of such an arylene group are shown below.

[0061]

[Chemical 16]

Next, the formula (4b) will be explained. In the formula (4b), M ₃ and M ₄ are M ₁ and M ₂ in the formula (4a), and q3 and q4 are the formula (4a).
Q1 and q2 in formula (4) and L ₂₀ have the same meanings as L ₁₀ in formula (4a), respectively, and the preferred ones are also the same.

In equation (4b), M₃ And M_Four Is the same as
Or they may be different, M ₃ And M_Four Multiple each
When present, M₃ Each other, M_Four They are the same or different
May be M₃ Mutually or M_Four Each other
They may combine with each other to form a ring such as a benzene ring, and form a ring.
It is also preferable to do.

Compounds represented by formula (4a) and formula (4b)
Examples of the present invention are shown below, but the present invention is not limited thereto.
is not. It should be noted that Chemical formula 17, Chemical formula 19, Chemical formula 21, Chemical formula 23,
25, 27, 29, and 32 show general formulas, and
8, chemical formula 20, chemical formula 22, chemical formula 24, chemical formula 26, chemical formula 28, chemical formula 3
0, Chemical formula 31, and Chemical formula 33, corresponding specific examples are M₁₁~ M
₁₅, M_{twenty one}~ M_{twenty five}Or M₃₁~ M₃₅, M₄₁~ M₄₅Set of
It is shown together.

[0065]

[Chemical 17]

[0066]

[Chemical 18]

[0067]

[Chemical 19]

[0068]

[Chemical 20]

[0069]

[Chemical 21]

[0070]

[Chemical formula 22]

[0071]

[Chemical formula 23]

[0072]

[Chemical formula 24]

[0073]

[Chemical 25]

[0074]

[Chemical formula 26]

[0075]

[Chemical 27]

[0076]

[Chemical 28]

[0077]

[Chemical 29]

[0078]

[Chemical 30]

[0079]

[Chemical 31]

[0080]

[Chemical 32]

[0081]

[Chemical 33]

[0082]

[Chemical 34]

[0083]

[Chemical 35]

[0084]

[Chemical 36]

[0085]

[Chemical 37]

The naphthacene derivative used in the present invention is preferably represented by the following formula (2).

[0087]

[Chemical 38]

In the formula (2), Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ , Q
^{50, Q 60, Q 70,} Q 80, Q 110, Q 1 20, Q 130 and Q
¹⁴⁰ represents hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, which may be the same or different. .

In the formula (2), Q ¹⁰ , Q ²⁰ , Q ^30, and Q ⁴⁰
(Collectively represented as Q ^{10 to} Q ⁴⁰ ) is preferably hydrogen, or any of an alkyl group, an aryl group, an amino group, a heterocyclic group and an alkenyl group. Further, it is more preferably an aryl group. Further, it is particularly preferable that Q ¹⁰ and Q ⁴⁰ are hydrogen and Q ²⁰ and Q ³⁰ are the above substituents.

Further, Q ¹⁰ and Q ⁴⁰ , and Q ²⁰ and Q ³⁰ are preferably the same, but they may be different.

Q ⁵⁰ , Q ⁶⁰ , Q ⁷⁰ and Q ⁸⁰ (collectively represented as Q ^{50 to} Q ⁸⁰ ) are preferably hydrogen, an alkyl group, an aryl group, an amino group, an alkenyl group or a heterocyclic group. , Particularly preferably hydrogen or an aryl group. Further, Q ⁵⁰ and Q ⁶⁰ , and Q ⁷⁰ and Q ⁸⁰ are preferably the same, but they may be different.
In addition, Q ¹¹⁰ , Q ¹²⁰ , Q ¹³⁰ and Q ¹⁴⁰ (collectively Q
Expressed as ¹¹⁰ to Q ^140. ) Is preferably hydrogen.

The alkyl group represented by Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ , and Q ^{110 to} Q ¹⁴⁰ may have a substituent and preferably has 1 to 6 carbon atoms, It may be linear or branched. Specific preferred examples of the alkyl group include a methyl group, an ethyl group, a (n, i) -propyl group, a (n, i, sec, tert) -butyl group,
(N, i, neo, tert) -pentyl group and the like.

Q^Ten ~ Q⁴⁰, Q⁵⁰~ Q⁸⁰, Q¹¹⁰~ Q¹⁴⁰
The aryl group represented by is a monocyclic or polycyclic group.
And may include fused rings and ring assemblies. Total carbon number
Is preferably 6 to 30, and even if it has a substituent
good. Q^Ten~ Q⁴⁰, Q⁵⁰~ Q ⁸⁰, Q¹¹⁰~ Q¹⁴⁰Represented by
The aryl group is preferably a phenyl group or (o
-, M-, p-) tolyl group, pyrenyl group, perylenyl
A group, a coronenyl group, a (1-, and 2-) naphthyl group,
Anthryl group, (o-, m-, p-) biphenylyl group,
Examples thereof include terphenyl group and phenanthryl group.

The amino group represented by Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ and Q ^{110 to} Q ¹⁴⁰ may be unsubstituted.
It is preferable to have a substituent, and any of an alkylamino group, an arylamino group, an aralkylamino group and the like may be used.
These are aliphatic having a total carbon number of 1 to 6, and / or 1
It is preferable to have ~ 4 aromatic carbocycles. Specific examples thereof include a dimethylamino group, a diethylamino group, a dibutylamino group, a diphenylamino group, a ditolylamino group, a bisdiphenylylamino group and a bisnaphthylamino group.

The heterocyclic group represented by Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ and Q ^{110 to} Q ¹⁴⁰ may have a substituent and contains O, N, S as a hetero atom. A 5- or 6-membered aromatic heterocyclic group having 2 to 6 carbon atoms
Examples include 20 condensed polycyclic aromatic heterocyclic groups and the like. Examples of the aromatic heterocyclic group and the condensed polycyclic aromatic heterocyclic group include a thienyl group, a furyl group, a pyrrolyl group, a pyridyl group, a quinolyl group and a quinoxalyl group.

The alkenyl group represented by Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ and Q ^{110 to} Q ¹⁴⁰ is at least one of the substituents.
Preferred are (1- and 2-) phenylalkenyl groups having one phenyl group, (1,2-, and 2,2-) diphenylalkenyl groups, and (1,2,2-) triphenylalkenyl groups. It may be a non-substituted one.

The alkoxy group and alkylthio group represented by Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ , and Q ^{110 to} Q ¹⁴⁰ may have a substituent, and those having the above-mentioned alkyl group. preferable.

The aryloxy group and arylthio group represented by Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ , and Q ^{110 to} Q ¹⁴⁰ may have a substituent and have 6 to 18 carbon atoms in total. Those having a group are preferable, and specific examples thereof include (o-, m-, p-) phenoxy group as an aryloxy group,
The arylthio group includes (o-, m-, p-) phenylthio group and the like.

The aralkyl group represented by Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ and Q ^{110 to} Q ¹⁴⁰ may have a substituent and preferably has 7 to 30 carbon atoms. Specific examples thereof include a benzyl group and a phenethyl group.

Q^Ten~ Q⁴⁰, Q⁵⁰~ Q⁸⁰, Q¹¹⁰~ Q¹⁴⁰But
When it has a substituent, especially Q^Ten~ Q ⁴⁰Then these substitutions
At least two of the groups are aryl groups, amino groups,
Any of a cyclic group, an alkenyl group and an aryloxy group
And an aryl group is particularly preferred.
It Aryl group, amino group, heterocyclic group and alkenyl
About the group Q above^Ten ~ Q⁴⁰ Is the same as.

Two or more of these substituents may form a condensed ring. Further, it may be further substituted, and in this case, preferable substituents are the same as above.

When Q ^{10 to} Q ⁴⁰ , Q ^{50 to} Q ⁸⁰ and Q ^{110 to} Q ¹⁴⁰ have a substituent, at least two or more of Q ^{10 to} Q ⁴⁰ may have the above substituent. preferable. The substitution position is not particularly limited, and when Q ^{10 to} Q ⁴⁰ have a phenyl group,
Any of meta, para, or ortho positions may be used.

In the formula (2), it is preferable that at least one of Q ^{10 to} Q ⁸⁰ , and further at least one of Q ^{10 to} Q ⁴⁰ is a substituted or unsubstituted aryl group.

Particularly, as the naphthacene derivative, those represented by the following formula (2a) are preferable, and those represented by the formula (2b) are also preferable. First, the formula (2a) will be described.

[0105]

[Chemical Formula 39]

In the formula (2a), Q ^{5 to} Q ⁸ and Q ^{11 to} Q ¹⁶ are
Each represents hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, which may be the same or different.
Q ^{21 to} Q ²⁵ and Q ^{51 to} Q ⁵⁵ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, These may be the same or different, and two or more adjacent to each other may bond to each other to form a ring.

Specific examples of these groups include Q ¹⁰ in the formula (2).
And the like.

In the formula (2a), Q ^{51 to} Q ⁵⁵ and Q ^{21 to} Q
²⁵ is preferably hydrogen, an aryl group, an amino group, a heterocyclic group, an aryloxy group or an alkenyl group, and particularly preferably an aryl group. Further, it is preferable that at least one of these groups has an aryl group, an amino group, a heterocyclic group, or an aryloxy group, particularly preferably an aryl group as a substituent. Two or more of these adjacent to each other may form a condensed ring. Preferred embodiments of the aryl group, amino group, heterocyclic group and aryloxy group are the same as the above Q ^{10 to} Q ⁴⁰ .

Q ^{51 to} Q ⁵⁵ and Q ^{21 to} Q ²⁵ are preferably the same, but they may be different.
The amino group serving as a substituent of Q ^{51 to} Q ⁵⁵ and Q ^{21 to} Q ²⁵ may be any of an alkylamino group, an arylamino group, an aralkylamino group and the like. These have a total carbon number of 1
It is preferable to have ~ 6 aliphatic and / or 1-4 aromatic carbocyclic rings. Specific examples thereof include a dimethylamino group, a diethylamino group, a dibutylamino group, a diphenylamino group, a ditolylamino group and a bisbiphenylylamino group.

Examples of the condensed ring to be formed include indene, naphthalene, anthracene, phenanthrene, quinoline, isoquinoline, quinoxaline, phenazine, acridine, indole, carbazole, phenoxazine,
Phenothiazine, benzothiazole, benzothiophene, benzofuran, acridone, benzimidazole,
Examples include coumarin and flavone.

Q ^{5 to} Q ⁸ in the formula (2a) have the same meanings as Q ⁵⁰ , Q ⁶⁰ , Q ⁷⁰ and Q ⁸⁰ in the formula (2), respectively.
Hydrogen is particularly preferable as Q ^{11 to} Q ¹⁶ .

[0112]

[Chemical 40]

In the formula (2b), Q ^{5 to} Q ⁸ , Q ^{11 to} Q ¹⁴ , Q
^{31 ~Q 35, Q 41 ~Q 45} , Q 61 ~Q 65, Q 71 ~Q 75 is of Q ¹⁰ such as defined in the formula (2).

In the formula (2b), Q ^{71 to} Q ⁷³ , Q ^{61 to} Q ⁶³ ,
Q ^{31 to} Q ³³ and Q ^{41 to} Q ⁴³ are preferably hydrogen, an aryl group, an amino group, a heterocyclic group, an aryloxy group or an alkenyl group, and particularly preferably an aryl group. Further, it is preferable that at least one group of these has an aryl group, an amino group, a heterocyclic group or an aryloxy group as a substituent, and an aryl group is particularly preferable. Two or more of these may combine to form a ring. Preferred embodiments of the aryl group, amino group, heterocyclic group and aryloxy group are the same as Q ^{10 to} Q ⁴⁰ in formula (2). Also, Q
^{71 to} Q ⁷³ and Q ^{41 to} Q ⁴³ , and Q ^{61 to} Q ⁶³ and Q ^{31 to} Q ³³ are preferably the same, but may be different.

The amino group as a substituent of Q ^{71 to} Q ⁷³ , Q ^{61 to} Q ⁶³ , Q ^{31 to} Q ³³ and Q ^{41 to} Q ⁴³ may be any of an alkylamino group, an arylamino group, an aralkylamino group and the like. Good. These are aliphatic having a total of 1 to 6 carbon atoms,
And / or it preferably has 1 to 4 aromatic carbocycles. Specific examples thereof include a dimethylamino group, a diethylamino group, a dibutylamino group, a diphenylamino group, a ditolylamino group and a bisbiphenylylamino group.

The ring formed is, for example, indene,
Naphthalene, anthracene, phenanthrene, quinoline, isoquinoline, quinoxaline, phenazine, acridine, indole, carbazole, phenoxazine,
Phenothiazine, benzothiazole, benzothiophene, benzofuran, acridone, benzimidazole,
Examples include coumarin and flavone.

Q in equation (2b)^Five~ Q⁸In the formula (2)
Q⁵⁰~ Q⁸⁰Is synonymous with ¹¹~ Q¹⁴, Q⁷⁴, Q
⁷⁵, Q⁶⁴, Q⁶⁵, Q⁴⁴, Q⁴⁵, Q³⁴, Q³⁵Especially hydrogen
preferable.

Especially, the naphthacene derivative is preferably a hydrocarbon compound.

Particularly preferred specific examples of the naphthacene derivative in the present invention include Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ of the formula (2),
Combination of Q ⁵⁰ , Q ⁶⁰ , Q ⁷⁰ , Q ⁸⁰ (however, Q ¹¹⁰
To Q ^{1 40} is hydrogen. ) Are shown below, but are not limited to these.

[0120]

[Chemical 41]

[0121]

[Chemical 42]

[0122]

[Chemical 43]

[0123]

[Chemical 44]

[0124]

[Chemical formula 45]

[0125]

[Chemical formula 46]

[0126]

[Chemical 47]

[0127]

[Chemical 48]

[0128]

[Chemical 49]

[0129]

[Chemical 50]

[0130]

[Chemical 51]

[0131]

[Chemical 52]

[0132]

[Chemical 53]

[0133]

[Chemical 54]

[0134]

[Chemical 55]

[0135]

[Chemical 56]

[0136]

[Chemical 57]

[0137]

[Chemical 58]

[0138]

[Chemical 59]

[0139]

[Chemical 60]

[0140]

[Chemical formula 61]

[0141]

[Chemical formula 62]

[0142]

[Chemical formula 63]

[0143]

[Chemical 64]

[0144]

[Chemical 65]

[0145]

[Chemical formula 66]

[0146]

[Chemical formula 67]

[0147]

[Chemical 68]

[0148]

[Chemical 69]

[0149]

[Chemical 70]

[0150]

[Chemical 71]

[0151]

[Chemical 72]

[0152]

[Chemical formula 73]

[0153]

[Chemical 74]

[0154]

[Chemical 75]

[0155]

[Chemical 76]

[0156]

[Chemical 77]

[0157]

[Chemical 78]

[0158]

[Chemical 79]

[0159]

[Chemical 80]

[0160]

[Chemical 81]

[0161]

[Chemical formula 82]

[0162]

[Chemical 83]

[0163]

[Chemical 84]

[0164]

[Chemical 85]

[0165]

[Chemical 86]

[0166]

[Chemical 87]

[0167]

[Chemical 88]

[0168]

[Chemical 89]

[0169]

[Chemical 90]

[0170]

[Chemical Formula 91]

[0171]

[Chemical Formula 92]

[0172]

[Chemical formula 93]

[0173]

[Chemical 94]

[0174]

[Chemical 95]

[0175]

[Chemical 96]

[0176]

[Chemical 97]

[0177]

[Chemical 98]

[0178]

[Chemical 99]

[0179]

[Chemical 100]

[0180]

[Chemical 101]

[0181]

[Chemical 102]

[0182]

[Chemical 103]

[0183]

[Chemical 104]

[0184]

[Chemical 105]

[0185]

[Chemical formula 106]

[0186]

[Chemical formula 107]

[0187]

[Chemical 108]

[0188]

[Chemical 109]

These naphthacene derivatives and anthracene derivatives may be used alone or in combination of two or more in the electron transport layer. When two or more kinds are used, they may be naphthacene derivatives or anthracene derivatives, or a combination of a naphthacene derivative and an anthracene derivative.

The content of the naphthacene derivative and / or the anthracene derivative in the electron transport layer is preferably 80% (mass percentage) or more, and other electron transport materials (for example, metal complex compounds, quinoxaline compounds, azole compounds, diazole compounds). ) May be used in combination, it is preferable that the electron-transporting layer is composed of only a naphthacene derivative and / or an anthracene derivative. Of these, the use of a naphthacene derivative is preferable, and in particular, the formula (2) (and further the formulas (2a) and (2b), especially the formula (2)
The use of naphthacene derivatives represented by a)) is preferred.

Materials used for the electron transport layer including the naphthacene derivative and / or the anthracene derivative are
The value of the dipole moment is preferably 1.0 Dybye or less, and more preferably 0.1 to 0.3 Dybye. The dipole moment in this case is obtained by the AM1 method using the semi-empirical molecular orbital method program (MPAC).

By using a nonpolar molecule having a small dipole moment in the electron transport layer, the electron transport property is enhanced.
The electron transporting property μ _a is as follows by the change of the driving voltage required to pass a current of 100 mA / cm ² when the thickness of the electron transporting layer is changed by using the organic EL device of the present invention. Is a parameter defined as follows. When the driving voltage (V) is V ₁ and V ₂ when the thickness (nm) of the electron transport layer is d ₁ and d ₂ (where d ₁ > d ₂ ), μ _a = (d ₁ −d ₂ ) /
(V ₁ −V ₂ ). This μ _a is preferably 80 nm / V or more, more preferably 100 nm / V or more. The upper limit is not particularly limited because a device that can be driven at a lower voltage can be created as the electron transporting property is higher. However, depending on the structure of the hole injecting / transporting layer or the light emitting layer, the electron transporting property is too high and the carrier balance is disturbed. Since there is a possibility that there is a possibility that the upper limit of the device structure of the present invention is about 600 nm / V.

As described above, by using the electron transporting layer having a high electron transporting property, it becomes possible to drive at a low voltage and the luminous efficiency is improved. In the present invention, the electron injection layer, the electron transport layer, and the light emitting layer are laminated in this order from the cathode side which is the electron injection electrode.
Since the electric field strength applied to the electron transport layer can be reduced, there is almost no change in the drive voltage even when the film thickness of the electron transport layer is changed to optimize the optical external extraction efficiency. It is possible to produce an element having both efficiency. In addition, since the probability of recombination of carriers in the electron transport layer due to the penetration of holes is reduced, light emission is suppressed in areas other than the light emitting layer, and color purity and device life are prevented from being shortened.

Furthermore, since the electron transport layer material of the present invention is a non-polar molecule, it is considered that the interaction with the light emitting material at the interface of the light emitting layer does not easily occur, and it also has an effect of preventing energy loss of excitons at the interface. To be

The preferred thickness of the electron transport layer varies depending on the color of light emitted from the device, but is preferably 5 to 100 nm, more preferably 10 to 60 nm. With such a thickness, the optimum optical interference effect can be obtained, and good external extraction efficiency can be obtained. Further, within the above range, there is no significant change in the driving voltage even if the film thickness of the electron transport layer is changed, so that the efficiency and color purity due to optical interference can be easily adjusted.

Further, as a means for preventing holes from leaking to the electron transport layer and improving efficiency, color purity, and device life, the ionization potential (IP) between the light emitting layer and the electron transport layer is higher than that of the light emitting layer. There is a method in which a large material is provided as the hole blocking layer, but this method has the adverse effect of shortening the device life because excitons are intensively generated on the electron transport layer side of the light emitting layer. In the combination of the electron-transporting layer and the light-emitting layer of the present invention, the electron-transporting layer of the electron-transporting layer is high and electrons can be well injected into the light-emitting layer, and the injected electrons are localized in the dopant molecule, so that the anode The holes injected from the side can be efficiently recombined. As a result, holes are not injected into the electron transport layer without providing a barrier that blocks holes between the light emitting layer and the cathode. Therefore, by reducing the difference in ionization potential (IP) between the light emitting layer and the electron transporting layer, the above-mentioned adverse effects can be prevented.

From the above, the difference in ionization potential (IP) between the electron transport layer and the light emitting layer is preferably 0.1 eV or less, and particularly preferably 0 to 0.1 eV.

In the present invention, the electron injection layer used in combination with the electron transport layer has good adhesion to both the cathode and the electron transport layer, can efficiently inject electrons from the cathode, and can obtain a high carrier concentration. It is preferable to use materials. In this case, an electron injection layer made of an inorganic compound can be considered, but it is preferable to select and use an organic compound. Depending on the organic compound, particularly when an alkali metal or an alkali metal compound is used for the electron injecting electrode, it is possible to form a complex with an alkali metal atom, further improving the adhesion and obtaining a high electron injecting property. In this case, the organic compound may include a metal such as a metal complex as well as a general carbon compound.

The electron injecting layer includes a quinoline derivative such as an organometallic complex having 8-quinolinol such as tris (8-quinolinolato) aluminum (Alq3) or a derivative thereof as a ligand, a phenanthroline or a phenanthroline derivative, an indole derivative (indole). ), Carbazole derivative (including carbazole), oxadiazole derivative (including oxadiazole), perylene derivative, pyridine derivative, acridine derivative, pyrimidine derivative, quinoxaline derivative, phenazine derivative, diphenylquinone derivative, nitro-substituted fluorene derivative. Various materials such as can be used.

Thus, the compound having a heterocycle is preferable, and the compound having a nitrogen-containing heterocycle is particularly preferable.

Among these, tris (8-quinolinolato)
Although aluminum and the like are generally used, phenanthroline or a phenanthroline derivative is preferably used because the adhesion to the cathode and the electron injection property are good. It is most preferable to use phenanthroline or a phenanthroline derivative, but good characteristics can be obtained even if an indole derivative, a carbazole derivative, a quinoxaline derivative, a phenazine derivative, an acridine derivative, an oxadiazole derivative, or the like is used.

Hereinafter, regarding these compounds,
This will be specifically described.

Examples of the phenanthroline derivative or phenanthroline derivative include 1,10-phenanthroline and 1,9-
Phenanthroline, 1,8-phenanthroline, 1,7-phenanthroline, 2,9-phenanthroline, 2,8-phenanthroline, 2,7-phenanthroline, 3,8-phenanthroline,
Organic compounds having 3,7-phenanthroline, 4,7-phenanthroline and one or more of these phenanthroline skeletons in the molecule are preferred.

As phenanthroline or a phenanthroline derivative, those disclosed in JP-A-5-331459 and JP-A-2001-267080 can be used, but are particularly represented by formula (1a) and formula (1b). One is preferable.

[0205]

[Chemical 110]

In formula (1a), Y _{2 to} Y ₉ may be the same or different and each represents hydrogen, an aryl group, an alkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, An alkenyl group,
It represents an amino group or a heterocyclic group, and two or more adjacent to each other may form a ring, but preferably an aryl group, an alkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an alkyl group, an amino group, a heterocycle. A group, particularly preferably an aryl group or an aromatic heterocyclic group.

Specific examples of these aryl group, alkyl group, aralkyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, amino group, alkenyl group and heterocyclic group are represented by Q ¹⁰ of the formula (2). It is similar to what is done.

Y ₉ is preferably hydrogen, a phenyl group, a biphenylyl group or a pyridyl group.

In formula (1b), A and B, which may be the same or different, each represents a group represented by formula (1c), and Y ₁₂ to Y ₁₉ in formula (1c) are Formula (1a)
It has the same meaning as Y ₂ to Y ₉ in the above. However, formula (1c)
One of Y ₁₂ to Y ₁₉ therein constitutes L. L represents a single bond or a divalent linking group, and as the divalent linking group represented by L, the anthracene derivative represented by the formula (4), the formula (4a) or the formula (4b) is mentioned. L ₁₀₁ , L
_10, L ₂₀ include those similar to, preferable ones are also same. Further, examples of the divalent linking group also include a divalent aromatic heterocyclic group (for example, a pyridinediyl group).

Also, in the formula (1c), Y which constitutes L
_{12 to} Y ₁₉ may be the same or different in A and B. That is, in the formula (1b), there is no particular limitation on the bonding position of the rings A and B having two phenanthroline skeletons, and the bonding positions of Y ₂ (2-position), Y ₃ (3-position) and Y ₄ (4-position) are not limited to each other. Although the bond is general, it may be a bond at different sites such as Y ₂ (position 2) and Y ₄ (position 4). Rings A and B having two phenanthroline skeletons may be the same or different, and the substituents and the like may be the same or different.

Specific examples of the phenanthroline or phenanthroline derivative used in the present invention are shown below, but the present invention is not limited thereto. Formula (f-1)
~ A specific example is shown according to the display in Formula (f-4).

[0212]

[Chemical 111]

[0213]

[Chemical 112]

[0214]

[Chemical 113]

[0215]

[Chemical 114]

[0216]

[Chemical 115]

[0217]

[Chemical formula 116]

[0218]

[Chemical 117]

[0219]

[Chemical 118]

[0220]

[Chemical formula 119]

[0221]

[Chemical 120]

[0222]

[Chemical 121]

[0223]

[Chemical formula 122]

[0224]

[Chemical 123]

[0225]

[Chemical formula 124]

[0226]

[Chemical 125]

[0227]

[Chemical formula 126]

[0228]

[Chemical 127]

[0229]

[Chemical 128]

[0230]

[Chemical formula 129]

[0231]

[Chemical 130]

[0232]

[Chemical 131]

[0233]

[Chemical 132]

[0234]

[Chemical 133]

[0235]

[Chemical 134]

[0236]

[Chemical 135]

As described above, the phenanthroline derivative is most preferable as the electron injection layer material in the present invention, but the nitrogen-containing heterocyclic compound having the basic skeleton as shown below is also preferable.

[0238]

[Chemical 136]

Here, Rn (R _{1 to} R ₆ ) is a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkenyl group,
It represents a heterocyclic group, a halogen atom, or a cyano group, which may be the same or different. Further, adjacent groups may be bonded or condensed with each other to form an aliphatic ring or an aromatic ring together with carbon atoms which are substituted.

Specific examples of these nitrogen-containing heterocyclic compounds are shown below, but the good electron injecting materials in the present invention are not limited to these.

As the indole derivative, an indole derivative having a skeleton represented by the formula (5) is preferable.

[0242]

[Chemical 137]

In the formula (5), R ^{1 to} R ⁷ are hydrogen,
Halogen atom, hydroxyl group, carboxyl group, cyano group, nitro group, amino group, alkyl group (eg, methyl group, ethyl group, propyl group, butyl group, etc.), alkenyl group (eg, ethynyl group, etc.), aryl group (eg, , Phenyl group, biphenyl group, terphenyl group etc.), aryloxy group (eg phenyloxy group etc.), alkyloxy group (eg methoxy group, ethoxy group etc.), arylcarbonyl group (eg phenylcarbonyl group etc.) Or an alkylcarbonyl group (for example, an acetyl group, a propionyl group, etc.), wherein each group has one substituent such as an alkyloxy group, an alkyl group, an aryl group, a nitro group, a cyano group, an amino group or a halogen atom. Or you may have two or more.

At least one of R ^{1 to} R ³ is preferably an aryl group or a group having an aryl group, more preferably all of them are aryl groups.

For example, a compound having a skeleton represented by the formula (5a) is preferable.

[0246]

[Chemical 138]

In the formula (5a), R ⁴¹ , R ⁴² and R
⁴³ is an alkoxy group (preferably having 1 to 5 carbon atoms, particularly 1 carbon atom), an alkyl group (preferably having 1 to 5 carbon atoms)
5), a dialkylamino group (preferably an alkyl having 1 to 5 carbon atoms) or a nitro group. p, q, r are 0
An integer of 3, p + q + r ≧ 1, preferably p + q +
r ≦ 6. R ⁴¹ , R ⁴² and R ⁴³ are usually bonded to the para position, but may be bonded to the ortho position.

The adjacent ones of R ^{1 to} R ⁷ may be bonded to each other to form a 5- or 6-membered, especially 6-membered condensed ring.

The alkyl group and alkenyl group are
It is preferable that the carbon number is 1 to 5. A phenyl group is preferable as the aryl group.

Further, examples of compounds in which the substituents are bonded to each other to form a condensed ring include compounds represented by the formulas (5b) and (5c). Further, a compound having a skeleton represented by the formula (5d) is also preferable.

[0251]

[Chemical 139]

In the formula (5b), R¹¹, R¹², R¹³,
R¹⁴Is the above R¹~ R⁷Choose from similar
Preferably, specifically, for example, R¹~ R³, R¹¹
~ R ¹⁴, R⁶~ R⁷Of which all are hydrogen are preferred
Yes.

[0253]

[Chemical 140]

In the formula (5c), R^{twenty one}, R^{twenty two}, R^{twenty three},
R^{twenty four}Is the above R¹~ R⁷Choose from similar
Preferably, specifically, for example, R¹~ R^Five, R^{twenty one}
~ R ^{twenty four}Are preferably all hydrogen.

[0255]

[Chemical 141]

In the formula (5d), R³¹, R³², R³³,
R³⁴, R³⁵, R³⁶Is the R¹~ R ⁷From something similar to
It is preferable to select. X is a bond, 1,4
-Phenylene, 4,4'-biphenylene, etc., and
Specifically, for example, X is a bond, 1,4-phenylene or
4,4'-biphenylene, R²~ R⁷, R³¹~
R³⁶Are preferably all hydrogen.

Specific examples of the indole derivative are shown below, but the invention is not limited thereto. Formula (Id-1)
~ Specific examples are shown according to the display in formula (Id-4).

[0258]

[Chemical 142]

[0259]

[Chemical 143]

[0260]

[Chemical 144]

[0261]

[Chemical 145]

[0262]

[Chemical 146]

[0263]

[Chemical 147]

[0264]

[Chemical 148]

[0265]

[Chemical 149]

[0266]

[Chemical 150]

[0267]

[Chemical 151]

[0268]

[Chemical 152]

[0269]

[Chemical 153]

[0270]

[Chemical 154]

[0271]

[Chemical 155]

[0272]

[Chemical 156]

[0273]

[Chemical 157]

As the quinoxaline derivative, those represented by the formula (6) are preferable. Q _m -L100 (6)

Explaining the formula (6), Q represents a pyrazinyl group condensed with a 6-membered aromatic ring containing 0 to 2 nitrogen atoms. m is 2 or 3, and the m Qs in this case may be the same or different. The 6-membered aromatic ring forming Q is preferably a benzene ring, a pyridine ring, a pyrimidine ring, a pyridazine ring or the like. The position of condensation between the 6-membered aromatic ring and the pyrazine ring is not particularly limited, but it is preferable that a carbon atom exists at the condensed position, and it is preferable that no nitrogen atom exists. Therefore, in the pyrazine ring, it is preferable to condense at the positions of position numbers 2 and 3 or the positions of position numbers 5 and 6, and in the pyridine ring, position numbers 2 and 3 are condensed.
(Or 5, 6) side or position number 3, 4 (or 4,5) side, position number 4, 5 (or 5, 6) side for pyrimidine ring, position number 3, 4 for pyridazine ring
It is preferable to condense on the side of (or 5, 6) or the side of position numbers 5, 4.

L100 represents a single bond or an m-valent group, that is, a divalent or trivalent group. The divalent group is preferably an arenediyl group, and specific examples thereof include a phenylene group, a biphenyldiyl group, a naphthalenediyl group, an anthracenediyl group and a pyrenediyl group, and the trivalent group includes an arenetriyl group (specifically, Specifically, a benzenetriyl group, etc.), a nitrogen atom, a triarylaminetriyl group (specifically, a triphenylaminetriyl group, etc.) and the like are preferable.

Each of Q and L100 may further have a substituent, and such a substituent may include Q, and the total number of Q in one molecule is preferably 2 to 10. , And more preferably 2 to 4.

As described above, two or more Q's may be the same or different, but it is usually preferable to be the same for convenience of synthesis.

Among the quinoxaline derivatives represented by the formula (6) used in the present invention, the compound represented by the formula (VIII) is preferable.

[0280]

[Chemical 158]

The formula (VIII) will be described below.
In I), Z represents an atomic group necessary for forming a benzene ring, a pyridine ring, a pyrimidine ring or a pyridazine ring together with two carbon atoms of the pyrazine ring.

The ring completed by Z may have a substituent or may have a condensed ring. Preferred fused positions of the ring completed by Z with respect to the pyrazine ring are the same as those shown in the explanation of formula (6).

A ₁ represents a monovalent substituent bonded to the pyrazine ring, and k is 0, 1 or 2. Suitable examples of the substituent of the ring completed by Z and the substituent represented by A ₁ are the same as A _{13 and the} like in the formulas (VIII-a) to (VIII-m) described later, and therefore are described in detail there. I will describe.

M is 2 or 3. L10 when m is 2
0 represents a single bond, a phenylene group, a biphenyldiyl group or a naphthalenediyl group, and when m is 3, L100 represents a benzenetriyl group, a nitrogen atom or a triphenylaminetriyl group, which are also represented by the formula (VIII-a ) -Formula (VIII-n).

The fused rings completed by Z may be the same or different, but are preferably the same as described in the formula (6).

The fused pyrazine ring having a ring completed by Z may be bonded to L100 at any position.

Among the quinoxaline compounds represented by the formula (VIII), the compounds represented by the formulas (VIII-a) to (VIII-n) are preferable.

[0288]

[Chemical 159]

[0289]

[Chemical 160]

[0290]

[Chemical 161]

[0291]

[Chemical 162]

[0292]

[Chemical formula 163]

First, formula (VIII-a) to formula (VIII-f) and formula (VIII-m) in the case where L100 is a divalent group L111 or a single bond will be described. In formulas (VIII-a) to (VIII-f) and formula (VIII-m), L111 represents a phenylene group, a biphenyldiyl group or a naphthalenediyl group.

As the phenylene group represented by L111,
It may be any of o-, m-, and p-phenylene groups, but a p-phenylene group is particularly preferable.

The biphenyldiyl group represented by L111 is preferably a 4,4'-biphenyl-1,1'-diyl group.

The naphthalenediyl group represented by L111 is preferably a 1,5-naphthalenediyl group.

Although these divalent groups are preferably unsubstituted, they may have a substituent such as an alkyl group or an aryl group depending on the case.

A ₁₃ , A _{15 to} A ₁₈ , A in the formula (VIII-a)
₂₃ , A _{25 to} A ₂₈ , A ₁₃ and A _{16 in} the formula (VIII-b) to
A ₁₈ , A ₂₃ , A _{26 to} A ₂₈ , A ₁₃ and A in the formula (VIII-c).
₁₅ , A ₁₇ , A ₁₈ , A ₂₃ , A ₂₅ , A ₂₇ , A ₂₈ , formula (VIII-
d) A ₁₃ , A ₁₆ , A ₁₈ , A ₂₃ , A ₂₆ , A ₂₈ in formula (VII)
A _13, A ₁₇ of I-e) _{in, A 18, A 23, A} 27, A 28, A 13 in formula _{(VIII-f), A 15} , A 18, A 23, A 25,
A _{1 2} of the A _28, and wherein _{(VIII-m), A 13} , A 15, A
₁₇ , A ₁₈ , A ₂₂ , A ₂₃ , A ₂₅ , A ₂₇ and A ₂₈ are each a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group,
Nitro group, cyano group, alkyl group, aryl group, alkoxy group, aryloxy group, amino group, alkylthio group,
It represents an arylthio group or a heterocyclic group, and in each formula, these may be the same or different.

As the halogen atom represented by A ₁₃ etc.,
Examples thereof include a fluorine atom and a chlorine atom.

The alkyl group represented by A ₁₃ etc. has a total carbon number of 1
Those having a molecular weight of from 6 to 6 are preferable, and they may be linear or branched. Also, the unsubstituted one is preferable,
It may have a substituent (for example, a halogen atom such as F or Cl). Specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, a pentyl group and a hexyl group.

The aryl group represented by A ₁₃ etc. has a total carbon number of 6
Those having a molecular weight of 30 to 30 are preferable, and they may be monocyclic or polycyclic (condensed polycyclic or ring assembly), and may have a substituent. Examples of the substituent include a halogen atom such as F and Cl, an alkyl group such as a methyl group, and a heterocyclic group. In this case, the heterocyclic group is represented by the formula (VIII-a).
Preferred are the same ones as the fused pyrazinyl group bonded to L111, such as the quinoxalinyl group in. Specific examples of the aryl group such as A ₁₃ include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenylyl group, a 3-biphenylyl group, a 4-biphenylyl group, and the like, and a condensation thereof such as a quinoxalinyl group. Examples thereof include those substituted with a pyrazinyl group.

The alkoxy group represented by A _{13 and the} like preferably has an alkyl moiety having 1 to 6 carbon atoms and may have a substituent, but an unsubstituted one is preferred. Specific examples thereof include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group and a t-butoxy group.

Examples of the aryloxy group represented by A ₁₃ include a phenoxy group.

The amino group represented by A _{13 and the} like may have a substituent, and examples of the substituent include an alkyl group and an aryl group. Specific examples include an amino group, a methylamino group, a dimethylamino group, a phenylamino group and a diphenylamino group.

Examples of the alkylthio group represented by A _{13 and the} like include a methylthio group and an ethylthio group.

Examples of the arylthio group represented by A _{13 and the} like include phenylthio group and the like.

Examples of the heterocyclic group represented by A _{13 and the} like include a fururi group, a cenyl group, a pyrrole group, a pyridyl group and a quinolyl group. Alternatively, it may be the same fused pyrazinyl group as that bonded to L ₁ such as the quinoxalinyl group in formula (VIII-a).

In the formula (VIII-a), A _{15 to} A ₁₈ , A
_{25 to} A ₂₈ are adjacent to each other, in formula (VIII-b), A _{16 to} A ₁₈ and A _{26 to} A ₂₈ are adjacent to each other, and in formula (VIII-c), A ₁₇ to A ₁₈ , A ₂₇ and A
₂₈ , in the formula (VIII-e), A ₁₇ and A ₁₈ , A ₂₇ and A ₂₈ , in the formula (VIII-m), A ₁₂ and A ₁₃ , A ₁₇ and A _28
18 , A ₂₂ and A ₂₃ , A ₂₇ and A ₂₈ may be bonded to each other to form a ring. The ring in this case is preferably a benzene ring or the like, and the benzene rings formed may be condensed with each other, and the benzene ring formed by these may further have a condensed ring.

In formulas (VIII-a) to (VIII-f),
A ₁₃ , A ₂₃ , and in the formula (VIII-m), A ₁₂ ,
A ₁₃ , A ₂₂ , and A ₂₃ are preferably an aryl group or the like. Further, A _{15 to} A ₁₈ and A _{25 to} A ₂₈ in the formula (VIII-a) are preferably hydrogen atoms, alkyl groups, alkoxy groups or those in which adjacent ones bond to each other to form a benzene ring. In addition, A _{16 to} A ₁₈ , A _{26 to} A _{28 of} the formula (VIII-b),
A ₁₅ , A ₁₇ , A ₁₈ , A ₂₅ , A _{27 of} the formula (VIII-c),
A ₂₈ , A _{16 of} formula (VIII-d), A ₁₈ , A ₂₆ , A ₂₈ , formula (V
III-e) A ₁₇ , A ₁₈ , A ₂₇ , A ₂₈ , A _{15 of} formula (VIII-f), A ₁₈ , A ₂₅ , A ₂₈ and A _{15 of} formula (VIII-m),
Each of A ₁₇ , A ₁₈ , A ₂₅ , A ₂₇ and A ₂₈ is preferably a hydrogen atom or the like.

Next, formulas (VIII-g) to (VIII-1) and formula (VIII-n) in the case where L100 is a trivalent group L112 will be described. Formula (VIII-g) to Formula (VIII-1), Formula (VIII
In -n), L112 represents a benzenetriyl group, a nitrogen atom or a triphenylaminetriyl group.

The benzenetriyl group represented by L112 is preferably a 1,3,5-benzenetriyl group.

The triphenylaminetriyl group represented by L112 is 4,4 ′, 4 ″ -triphenyl-1,
A 1 ′, 1 ″ -triyl group and the like are preferable.

These trivalent groups are preferably unsubstituted, but may have a substituent such as an alkyl group or an aryl group depending on the case.

A ₁₃ , A _{15 to} A ₁₈ , A in the formula (VIII-g)
₂₃ , A _{25 to} A ₂₈ , A ₃₃ , A _{35 to} A ₃₈ , A ₁₃ , A _{16 to} A ₁₈ , A ₂₃ , A _{26 to} A ₂₈ , A ₃₃ , and A ₃₆ to in the formula (VIII-h).
A ₃₈ , A ₁₃ , A ₁₅ , A ₁₇ , A ₁₈ and A in the formula (VIII-i)
₂₃ , A ₂₅ , A ₂₇ , A ₂₈ , A ₃₃ , A ₃₅ , A ₃₇ , A ₃₈ , A ₁₃ , A ₁₆ , A ₁₈ , A ₂₃ , A ₂₆ in the formula (VIII-j),
A ₂₈ , A ₃₃ , A ₃₆ , A ₃₈ , A ₁₃ and A in the formula (VIII-k)
₁₇ , A ₁₈ , A ₂₃ , A ₂₇ , A ₂₈ , A ₃₃ , A ₃₇ , A ₃₈ , A ₁₃ , A ₁₅ , A ₁₈ , A ₂₃ , A ₂₅ in the formula (VIII-1),
A ₂₈ , A ₃₃ , A ₃₅ , A ₃₈ , A ₁₂ and A in the formula (VIII-n)
₁₃ , A ₁₅ , A ₁₇ , A ₁₈ , A ₂₂ , A ₂₃ , A ₂₅ , A ₂₇ ,
A ₂₈ , A ₃₂ , A ₃₃ , A ₃₅ , A ₃₇ and A ₃₈ are each a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group, a nitro group, a cyano group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, It represents an amino group, an alkylthio group, an arylthio group or a heterocyclic group, and in each formula, these may be the same or different. Specific examples of these groups include the same groups as those mentioned in the formula (VIII-a) to formula (VIII-f). Also, the formula (VI
In _{II-g), A 15 ~A} 18, A 2 5 ~A 28, A 35 ~A
Adjacent to each other among ₃₈ , in formula (VIII-h), adjacent among A _{16 to} A ₁₈ , A _{26 to} A ₂₈ , A _{36 to} A ₃₈ , in formula (VIII-i), A ₁₇ and A ₁₈ ,
A ₂₇ and A ₂₈ , A ₃₇ and A ₃₈ , in the formula (VIII-k), A
₁₇ and A ₁₈ , A ₂₇ and A ₂₈ , A ₃₇ and A ₃₈ , in the formula (VIII-n), A ₁₂ and A ₁₃ , A ₁₇ and A ₁₈ , A ₂₂ and A ₂₃ , A ₂₇ and A ₂₈ , A ₃₂ and A ₃₃ , and A ₃₇ and A ₃₈ may be bonded to each other to form a ring, and specific examples thereof are the same as those in formula (VIII-a) to formula (VIII-f). Can be mentioned. In the formulas (VIII-a) to (VIII-1), A
Preferred as ₁₃ , A ₂₃ and A ₃₃ are a hydrogen atom and an aryl group such as a phenyl group.

In addition, A _{15 to} A ₁₈ , A _{25 of the} formula (VIII-g)
It is preferable that each of A ₂₈ to A ₃₅ and A _{35 to} A ₃₈ is a hydrogen atom or those adjacent to each other are bonded to each other to form a benzene ring.

In addition, A _{16 to} A ₁₈ and A _{26 of the} formula (VIII-h)
To A ₂₈ , A _{36 to} A ₃₈ , A ₁₅ , A ₁₇ , and A of the formula (VIII-i).
₁₈ , A ₂₅ , A ₂₇ , A ₂₈ , A ₃₅ , A ₃₇ , A ₃₈ , formula (VIII-
j) A ₁₆ , A ₁₈ , A ₂₆ , A ₂₈ , A ₃₆ , A ₃₈ , the formula (VIII
-K) A ₁₇ , A ₁₈ , A ₂₇ , A ₂₈ , A ₃₇ , A ₃₈ , the formula (VII
I-1) A ₁₅ , A ₁₈ , A ₂₅ , A ₂₈ , A ₃₅ , A ₃₈ , and the formula (VI
II-n) A ₁₂ , A ₁₃ , A ₁₅ , A ₁₇ , A ₁₈ , A ₂₂ ,
A ₂₃ , A ₂₅ , A ₂₇ , A ₂₈ , A ₃₂ , A ₃₃ , A ₃₅ , A ₃₇ , A
Each ₃₈ is preferably a hydrogen atom or the like.

The formulas preferably used in the present invention are shown below.
Specific examples of the quinoxaline derivative represented by (6) are shown below.
The present invention is not limited to these. here,
L111, L112, and A in formulas (VIII-a) to (VIII-m)
₁₃It is displayed as a combination of ₁₃And A_{twenty three}When is different
They are shown separately in the table. In addition, Formula (VIII-a) -Formula (V
III-m) is a typical example, and the compound actually obtained
Is usually a mixture of structural isomers on the synthetic route
However, these labels are intended to include the corresponding structural isomers.
It

[0318]

[Chemical 164]

[0319]

[Chemical 165]

[0320]

[Chemical 166]

[0321]

[Chemical 167]

[0322]

[Chemical 168]

[0323]

[Chemical 169]

[0324]

[Chemical 170]

[0325]

[Chemical 171]

[0326]

[Chemical 172]

[0327]

[Chemical 173]

[0328]

[Chemical 174]

[0329]

[Chemical 175]

[0330]

[Chemical 176]

[0331]

[Chemical 177]

[0332]

[Chemical 178]

[0333]

[Chemical 179]

[0334]

[Chemical 180]

[0335]

[Chemical 181]

[0336]

[Chemical 182]

[0337]

[Chemical 183]

[0338]

[Chemical 184]

[0339]

[Chemical 185]

[0340]

[Chemical 186]

[0341]

[Chemical 187]

[0342]

[Chemical 188]

[0343]

[Chemical 189]

[0344]

[Chemical 190]

[0345]

[Chemical 191]

[0346]

[Chemical 192]

[0347]

[Chemical formula 193]

[0348]

[Chemical 194]

[0349]

[Chemical 195]

[0350]

[Chemical 196]

[0351]

[Chemical 197]

[0352]

[Chemical 198]

[0353]

[Chemical formula 199]

[0354]

[Chemical 200]

[0355]

[Chemical 201]

[0356]

[Chemical 202]

[0357]

[Chemical 203]

[0358]

[Chemical 204]

[0359]

[Chemical 205]

[0360]

[Chemical 206]

[0361]

[Chemical formula 207]

[0362]

[Chemical 208]

[0363]

[Chemical 209]

[0364]

[Chemical 210]

[0365]

[Chemical 211]

[0366]

[Chemical 212]

[0367]

[Chemical 213]

[0368]

[Chemical 214]

[0369]

[Chemical 215]

[0370]

[Chemical 216]

[0371]

[Chemical 217]

[0372]

[Chemical 218]

[0373]

[Chemical 219]

[0374]

[Chemical 220]

[0375]

[Chemical 221]

[0376]

[Chemical 222]

[0377]

[Chemical formula 223]

[0378]

[Chemical formula 224]

[0379]

[Chemical formula 225]

[0380]

[Chemical formula 226]

[0380]

[Chemical 227]

[0382]

[Chemical 228]

[0383]

[Chemical formula 229]

[0384]

[Chemical 230]

[0385]

[Chemical formula 231]

[0386]

[Chemical 232]

[0387]

[Chemical formula 233]

[0388]

[Chemical formula 234]

[0389]

[Chemical formula 235]

[0390]

[Chemical 236]

[0391]

[Chemical 237]

As the oxadiazole derivative, those represented by the formula (7) are preferable.

[0393]

[Chemical 238]

In formula (7), Z ₀ is hydrogen, an alkyl group (eg, methyl group, ethyl group, etc.), an aryl group (eg, phenyl group, naphthyl group, etc.), an alkoxy group (eg, methoxy group, ethoxy group). Etc.), aryloxy group
(For example, phenoxy group etc.), heterocyclic group (for example, pyridyl group, thienyl group etc.), nitro group, cyano group, amino group, hydroxyl group, carboxyl group or alkenyl group, an alkyl group, an aryl group, an alkoxy group, The aryloxy group, the heterocyclic group, the amino group, and the alkenyl group may further have a substituent, and some of these groups have been specifically described above, but are similar to Q ¹⁰ and the like of the formula (2). There are things. Z ₀ is preferably an aryl group such as a phenyl group, and may further have a substituent. In that case, the substituent is represented by Z ₀ (an alkyl group, an aryl group, Alkoxy group, aryloxy group, heterocyclic group, etc.). n ₅₀ is 1, 2 or 3, and preferably 2 or 3.

X ₅₀ is a substituent similar to Z ₀ when n ₅₀ = 1 or hydrogen, and when n ₅₀ = 2, a divalent linking group (eg, a phenylene group) linking two oxadiazolyl groups. , Biphenyldiyl group), and when n ₅₀ = 3, 3
It is a trivalent linking group that links two oxadiazolyl groups (for example, a benzenetriyl group). Also, n ₅₀ = 2,
In the case of 3, the plural oxadiazolyl groups linked by X ₅₀ may be the same or different.

Specific examples of the oxadiazole derivative are shown below, but the invention is not limited thereto. Formula (7-
1) and a specific example is shown according to the expression in the formula (7-2).

[0397]

[Chemical 239]

[0398]

[Chemical 240]

[0399]

[Chemical 241]

[0400]

[Chemical 242]

[0401]

[Chemical formula 243]

[0402]

[Chemical formula 244]

As the carbazole derivative, those represented by the formula (8) are preferable.

[0404]

[Chemical 245]

In the formula (8), R _{52 to} R ₅₉ are hydrogen,
Alkyl group (eg, methyl group, ethyl group, etc.), aryl group (eg, phenyl group, naphthyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, etc.), aryloxy group (eg, phenoxy group, etc.), heterocycle Group (for example, pyridyl group, thienyl group, etc.), nitro group, cyano group, amino group, hydroxyl group, carboxyl group or alkenyl group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a heterocyclic group, an amino group, The alkenyl group may further have a substituent, and specific examples of these groups include the same as those of Q ¹⁰ and the like in the formula (2), although some of them have been described above. n ₅₁ is 1 or 2, and 2 is preferable. X ₅₁ is the same substituent or hydrogen as R _{52 to} R ₅₉ when n ₅₁ = 1 and a divalent linking group (eg, a phenylene group) that connects two carbazolyl groups when n ₅₂ = 2. Etc.). When n = 2, the carbazolyl groups linked by X ₅₁ may be the same or different.

Specific examples of the carbazole derivative are shown below, but the invention is not limited thereto. Formula (8-1)
A specific example is shown according to the display inside.

[0407]

[Chemical formula 246]

[0408]

[Chemical 247]

Further, the effects of the present invention can be obtained by using a general electron injection material such as a boron compound or a silacyclopentadiene derivative shown below.

Examples of boron compounds include the following.

[0411]

[Chemical 248]

Here, Rn (R ₁₁ , R ₁₂ ) is a hydrogen atom,
Alkyl group, aryl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkenyl group,
A heterocyclic group, a halogen atom, a cyano group, an alkylboryl group, and an arylboryl group are shown. Ar represents an aryl group or a heterocyclic group.

Specific examples are shown below, but the present invention is not limited thereto. These compounds are disclosed in JP 2001-23
No. 3882, Polymer Preprints, Japan, Vol.48,
No.9, 2047-2048, 1999, International Symp. On func
tional dyes, 36, 1999.

[0414]

Embedded image

As the silacyclopentadiene derivative,
Some examples are as follows.

[0416]

[Chemical 250]

Here, Rn (R ₂₁ , R ₂₆ ) is a hydrogen atom,
Alkyl group, aryl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, alkenyl group,
A heterocyclic group, a halogen atom, a cyano group, an alkylboryl group, and an arylboryl group are shown. Further, adjacent groups may be bonded or condensed with each other to form an aliphatic ring or aromatic ring together with carbon atoms which are substituted.

Specific examples are shown below, but the present invention is not limited thereto. These compounds are disclosed in JP-A-2002-33
It is described in Japanese Patent No. 8581, Japanese Patent Laid-Open No. 2002-216972, and the like.

[0419]

[Chemical 251]

In addition to these, Japanese Patent Laid-Open Nos. 2000-103786, 2000-306670 and 200
No. 2-38141, Japanese Patent Laid-Open No. 2001-57292, Japanese Patent Laid-Open No. 2001-244076, Japanese Patent Laid-Open No. 5-2.
1165, JP 2001-335776 A,
JP-A-7-82552 and JP-A-10-25163.
The compounds described in JP-A No. 4 and JP-A No. 9-3448 can be used. Including these compounds,
The compounds that can be used in the present invention are exemplified.

[0421]

[Chemical 252]

[0422]

[Chemical 253]

In the electron injection layer, only one organic compound may be used, or two or more organic compounds may be used in combination. When two or more kinds are used, the same kind or different kinds may be used.

Among these, it is preferable to use a phenanthroline derivative, particularly a phenanthroline or a phenanthroline derivative represented by the formula (1a) or (1b), and the phenanthroline or phenanthroline derivative is contained in an amount of 80% (mass percentage) or more. Is preferred, and particularly preferably phenanthroline or a phenanthroline derivative.

The thickness of the electron injection layer is preferably 0.6 to 20 nm, more preferably 1 to 10 nm. The driving voltage can be reduced in such a thickness range. On the other hand, when the electron injection layer becomes thin, the driving voltage rises critically, and even when it becomes thick, the driving voltage rises. This is because if the thickness is too thin, the adhesion with the cathode is lowered and the electron injection property is deteriorated.Because the material of the electron injection layer has a low electron transport property, it is considered that the voltage rises if it is too thick. .

Further, the total thickness of the electron injection layer and the electron transport layer is preferably 5 to 100 nm. With such a total thickness, electrons can be efficiently injected and transported, and optically good external extraction efficiency can be obtained. On the other hand, when the total thickness of these layers becomes large, the driving voltage rises, and even when the driving voltage is made thin and the driving voltage is lowered, if the film thickness is not optically optimum, the extraction efficiency to the outside is lowered.

In the present invention, the light emitting layer provided in contact with the electron transport layer preferably contains a host material and a dopant material.

Examples of the host material in this case include naphthacene derivatives, anthracene derivatives, tetraaryldiamine derivatives, quinoxaline derivatives, metal complex compounds, and the like. It is preferable to use anthracene derivatives and naphthacene derivatives, and naphthacene derivatives are particularly preferable.

As the naphthacene derivative, the same ones as those for the electron transport layer can be used, and the preferable ones are also the same, and particularly preferably the formula (2) (further, the formulas (2a) and (2b)). , Particularly a naphthacene derivative represented by the formula (2a)).

The host material has a dipole moment of 1.0.
It is preferably Dybe or less, more preferably 0.5 to 0 Dybe. By using such a non-polar molecule, the electron transporting property is increased, electrons are easily trapped by the dopant material, and the electrons are localized in the dopant. Therefore, the emission of the dopant material can be promoted and the emission of the host material can be suppressed. It is also possible to suppress the interaction between the host molecule and the dopant. Therefore, an element having high efficiency and high color purity can be obtained.

The electron affinity of the host material contained in the light emitting layer, particularly preferably the naphthacene derivative, is preferably higher than or the same as the electron affinity of the electron transport layer. Further, when the hole injecting and transporting layer is provided, it is preferable that the hole injecting and transporting layer has a larger electron affinity. If the electron affinity of the host material contained in the light emitting layer is higher than that of the electron transport layer, the efficiency of electron injection into the light emitting layer is improved, and if it is higher than that of the hole injecting and transporting layer, hole injecting and transporting. Electrons are blocked at the layer interface, so that the luminous efficiency is improved and the device life is also improved.

Further, the light emitting layer needs a function of injecting holes and holes, a function of transporting them, and a function of generating excitons by recombination of holes and electrons, so that the host is relatively close to the host. By using an electronically neutral compound, electrons and holes can be easily and well-balanced.
Can be transported.

The host material in the light emitting layer is 8
It is preferable that the content is 0 to 99.9% (mass percentage), particularly 90 to 99.9% (mass percentage), and further 95.0 to 99.5% (mass percentage). preferable.

The thickness of the light emitting layer is preferably less than the total thickness of the organic compound layer in the device, from the thickness corresponding to one molecular layer, specifically, 1 to 85 nm. Further, it is preferably 5 to 60 nm, and particularly preferably 5 to 50 nm.

On the other hand, the dopant material may be any material as long as it can emit light by itself and trap electrons in the host material, but it is preferable to use a fluoranthene derivative.

The fluoranthene derivative is represented by the formula (3)
What is represented by is preferable.

[0437]

[Chemical formula 254]

In the formula (3), n ₁₀ is 1 or 2. Z
_{1 to} Z ₁₀ , and L ₁₁ and L ₁₂ when n ₁₀ = 1 are hydrogen, halogen, a linear or branched alkyl group which may have a substituent, or a substituent which may have a substituent. Good straight chain, branched or cyclic alkyl moiety having an alkyl moiety, straight chain optionally having a substituent, alkylthio group having a branched or cyclic alkyl moiety, straight chain optionally having a substituent, A branched or cyclic alkenyl group, a linear chain which may have a substituent, an alkenyloxy group which has a branched or cyclic alkenyl moiety, and a linear, branched or cyclic alkenyl moiety which may have a substituent Having an alkenylthio group, a substituted or unsubstituted aromatic ring-containing alkyl group, a substituted or unsubstituted aromatic ring alkyl-containing oxy group, a substituted or unsubstituted aromatic ring-containing alkylthio group,
Substituted or unsubstituted aromatic ring group, substituted or unsubstituted aromatic ring oxy group, substituted or unsubstituted aromatic ring thio group, substituted or unsubstituted amino group, cyano group, hydroxyl group, -COOR
₁ (wherein R ₁ is hydrogen, a linear, branched or cyclic alkyl group which may have a substituent, a linear, branched or cyclic alkenyl group which may have a substituent, a substituted or An unsubstituted aromatic ring group-containing alkyl group or a substituted or unsubstituted aromatic ring group), -COR ₂ (wherein R ₂
Is hydrogen, a linear, branched or cyclic alkyl group which may have a substituent, a linear, branched or cyclic alkenyl group which may have a substituent, a substituted or unsubstituted aromatic ring-containing alkyl Group, a substituted or unsubstituted aromatic ring group, or an amino group), or —OCOR ₃ (wherein
R ₃ is a linear, branched or cyclic alkyl group which may have a substituent, a linear, branched or cyclic alkenyl group which may have a substituent, a substituted or unsubstituted aromatic ring-containing alkyl Group, or a substituted or unsubstituted aromatic ring group), and two or more adjacent groups selected from Z _{1 to} Z ₁₀ and L ₁₁ and L ₁₂ are bonded to each other and substituted. A substituted or unsubstituted aliphatic carbon ring, aromatic ring, or condensed ring of an aliphatic carbon ring and an aromatic ring may be formed together with the carbon atom. Also, n ₁₀ = 2,
When at least one of L ₁₁ and L ₁₂ is a single bond, the other represents the same group as when n ₁₀ = 1 and it is the same that a ring may be formed in the same manner as above. Also,
It is the same that both L ₁₁ and L ₁₂ may be a single bond, and in this case as well, a ring may be formed as described above.

Further, in the formula (3), two or more adjacent groups selected from Z _{1 to} Z ₁₀ and L ₁₁ and L ₁₂ are bonded to each other to form a substituted or unsubstituted group together with the carbon atom which is substituted. It is preferable to form an aliphatic carbocycle, an aromatic ring, or a condensed ring of an aliphatic carbocycle and an aromatic ring. Further, when n ₁₀ = 2, it is also preferable that both L ₁₁ and L ₁₂ are single bonds.

Among the compounds represented by the formula (3), diindeno [1,2,3-cd: especially represented by the formula (3a):
1 ', 2', 3'-lm] perylene derivatives are preferred.

[0441]

[Chemical 255]

In the formula (3a), Z _{1 to} Z ₆ , Z ₉ , Z ₁₀ and Z
_{11 to} Z ₁₆ , Z ₁₉ and Z ₂₀ are hydrogen, halogen, a linear, branched or cyclic alkyl group which may have a substituent, a linear, branched or cyclic which may have a substituent. Alkoxy group having alkyl moiety, linear, branched or cyclic alkylthio group having alkyl moiety which may have substituent, linear, branched or cyclic alkenyl group which may have substituent, substituted A linear, branched or cyclic alkenyl moiety-containing alkenyloxy group which may have a group, a linear, branched or cyclic alkenyl moiety-containing alkenylthio group which may have a substituent,
Substituted or unsubstituted aromatic ring-containing alkyl group, substituted or unsubstituted aromatic ring-containing alkyloxy group, substituted or unsubstituted aromatic ring-containing alkylthio group, substituted or unsubstituted aromatic ring group, substituted or unsubstituted aromatic ring An oxy group, a substituted or unsubstituted aromatic ring thio group, a substituted or unsubstituted aromatic ring alkenyl group, a substituted or unsubstituted alkenyl aromatic ring group,
Substituted or unsubstituted amino group, cyano group, hydroxyl group, -C
OOR ₁ (wherein R ₁ is hydrogen, a linear, branched or cyclic alkyl group which may have a substituent, a linear, branched or cyclic alkenyl group which may have a substituent, a substituent Or an unsubstituted aromatic ring-containing alkyl group, or a substituted or unsubstituted aromatic ring group), -COR ₂ (wherein
R ₂ is hydrogen, a straight chain which may have a substituent, a branched or cyclic alkyl group, a straight chain which may have a substituent,
A branched or cyclic alkenyl group, a substituted or unsubstituted aromatic ring-containing alkyl group, a substituted or unsubstituted aromatic ring group, or an amino group), or -OCOR ₃ (wherein R ₃ has a substituent) Optionally linear, branched or cyclic alkyl group, optionally substituted linear, branched or cyclic alkenyl group, substituted or unsubstituted aromatic ring-containing alkyl group, or substituted or unsubstituted represents an aromatic ring group), _{further, Z 1 ~Z 6, Z 9} , Z 10, Z
₁₁ to Z _16, a group selected from an adjacent group selected from Z _19, Z _20, taken together, together with the carbon atom substituted, substituted or unsubstituted aliphatic carbocyclic, aromatic ring or aliphatic, A condensed ring of a carbocycle and a condensed aromatic ring may be formed.

The aromatic ring group is, for example, an aromatic hydrocarbon group (aryl group) such as phenyl group and naphthyl group.
And, for example, an aromatic heterocyclic group such as a furyl group, a thienyl group, a pyridyl group, etc., among which an aryl group is preferable. The same applies to the following.

In the formulas (3) and (3a), Z _{1
~Z 6, Z 9, Z 10} , Z 11 ~Z 16, Z 19, a straight chain represented by Z _20, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a straight-chain, branched or A cyclic alkylthio group, a linear, branched or cyclic alkenyl group, a linear, branched or cyclic alkenyloxy group, and a linear, branched or cyclic alkenylthio group are each
Further, it may have a substituent, for example, halogen, an aromatic ring group having 4 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkoxyalkoxy group having 2 to 20 carbon atoms,
Alkenyloxy group having 2 to 20 carbon atoms, 4 to 20 carbon atoms
Aromatic ring-containing alkyloxy group, C5-20 aromatic ring-containing alkyloxyalkoxy group, C3-20 aromatic ring oxy group, C4-20 aromatic ring oxyalkoxy group, C5-20 Aromatic ring alkenyl group, aromatic ring-containing alkylalkenyl group having 6 to 20 carbon atoms, carbon number 1
To C20 alkylthio group, C2 to C20 alkoxyalkylthio group, C2 to C20 alkylthioalkylthio group, C2 to C20 alkenylthio group, C4 to C20 aromatic ring-containing alkylthio group, and carbon number 5-20
Aromatic ring-containing alkyloxyalkylthio groups with 5 carbon atoms
˜20 aromatic ring-containing alkylthioalkylthio group, C 3-20 aromatic ring thio group, C 4-20 aromatic oxyalkylthio group, C 4-20 aromatic ring thioalkylthio group, C 4-20 It may be mono-substituted or poly-substituted with the alicyclic heterocyclic group. Furthermore, the aromatic ring group contained in these substituents is further halogen, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aromatic ring group having 3 to 10 carbon atoms, and 4 to 10 carbon atoms. It may be substituted with an aromatic ring-containing alkyl group or the like.

In formulas (3) and (3a), Z _{1 to} Z ₆ ,
An aromatic ring-containing alkyl group represented by Z ₉ , Z ₁₀ , Z _{11 to} Z ₁₆ , Z ₁₉ , and Z ₂₀ , an aromatic ring-containing alkyloxy group, an aromatic ring-containing alkylthio group, an aromatic ring group, an aromatic ring oxy group, and The aromatic ring group in the aromatic ring thio group may have a substituent, and examples thereof include an alkyl group having 1 to 20 carbon atoms and 2 carbon atoms.
-20 alkenyl groups, C4-20 aromatic ring-containing alkyl groups, C3-20 aromatic ring groups, C1-20
Alkoxy group, C2-C20 alkoxyalkyl group, C2-C20 alkoxyalkyloxy group, C2-C20 alkenyloxy group, C3-C20 alkenyloxyalkyl group, C3-C3 20 alkenyloxyalkyloxy groups, C4-20 aromatic ring-containing alkyloxy groups, C5-20 aromatic ring-containing alkyloxyalkyl groups, C5-20 aromatic ring-containing alkyloxyalkyloxy groups, Aromatic ring oxy group having 3 to 20 carbon atoms, aromatic ring oxyalkyl group having 4 to 20 carbon atoms, aromatic ring oxyalkyloxy group having 4 to 20 carbon atoms,
Alkylcarbonyl group having 2 to 20 carbon atoms, 3 to 2 carbon atoms
0 alkenylcarbonyl group, C5-20 aromatic ring-containing alkylcarbonyl group, C4-20 aromatic ring carbonyl group, C2-20 alkoxycarbonyl group, C3-20 alkenyloxycarbonyl group ,
Aromatic ring-containing alkyloxycarbonyl group having 5 to 20 carbon atoms, aromatic ring oxycarbonyl group having 4 to 20 carbon atoms, alkylcarbonyloxy group having 2 to 20 carbon atoms, and 3 to carbon atoms
20 alkenylcarbonyloxy groups, 5 to 20 carbon atoms
Aromatic ring-containing alkylcarbonyloxy group having 4 to 4 carbon atoms
20 aromatic ring carbonyloxy group, C1-20 alkylthio group, C4-20 aromatic ring-containing alkylthio group, C3-20 aromatic ring thio group, nitro group, cyano group, formyl group, halogen , A halogenated alkyl group,
It may be mono- or polysubstituted with a substituent such as a hydroxyl group, an amino group, an N-mono-substituted amino group having 1 to 20 carbon atoms, and an N, N-di-substituted amino group having 2 to 40 carbon atoms.

Further, the aromatic ring group contained in these substituents is further halogen, an alkyl group having 1 to 10 carbon atoms,
It may be substituted with an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, and the like.

In formulas (3) and (3a), Z _{1 to} Z ₆ ,
Amino group represented by _{Z 9, Z 10, Z 11} ~Z 16, Z 19, Z 20 may have a substituent, for example, 1 carbon atoms
It may be mono-substituted or di-substituted with a 20 alkyl group, a C4-20 aromatic ring-containing alkyl group, or a C3-20 aromatic ring group.

In the formulas (3) and (3a), the alkyl group, the alkenyl group, the aromatic ring-containing alkyl group and the aryl group represented by R ₁ , R ₂ and R ₃ in the ester group or the acyl group may have a substituent. You may have, for example, Z ₁ ~
_{Z 6, Z 9, Z 10} , Z 11 ~Z 1 6, Z 19, may be mono- or polysubstituted by substituents listed in Z _20.

Z _{1 to} Z ₆ , Z ₉ , Z ₁₀ , Z _{11 to} Z ₁₆ , Z
₁₉ , Z ₂₀ is preferably Z ₅ , Z ₆ , Z ₉ , Z ₁₀ ,
Z ₁₅ , Z ₁₆ , Z ₁₉ and Z ₂₀ are hydrogen, and Z ₁ to
Z ₄ , Z _{11 to} Z ₁₄ are hydrogen, halogen, a linear, branched or cyclic alkyl group having a total carbon number of 1 to 24, which may have a substituent, and a total carbon which may have a substituent. Number 1 to 24
An alkoxy group having a linear, branched or cyclic alkyl moiety, an optionally substituted linear, branched or cyclic alkenyl group having 2 to 24 carbon atoms, or an alkenyl having such an alkenyl group. Aryl group or arylalkenyl group (total carbon number 8 to 30), substituted or unsubstituted aralkyl group having total carbon number 7 to 24, substituted or unsubstituted aryl group or aryloxy group having total carbon number 6 to 24, cyano Group, heterocyclic group, hydroxyl group, -COO
R ₁ , —COR ₂ or —OCOR ₃ (wherein R _{1 to} R ₃ have the same meanings as described above).

Further, in the equation (3), L ₁₁ , L ₁₂ ,
Z _{1 to} Z ₆ , Z ₉ and Z ₁₀ , Z _{1 to} Z in formula (3a)
_{6, Z 9, Z 10,} Z 11 adjacent groups selected from to Z _16, Z ₁₉ and Z ₂₀ are bonded to each other, together with the carbon atom substituted, substituted or unsubstituted aliphatic carbocyclic, aromatic An embodiment in which a ring or a condensed ring of an aliphatic carbon ring and an aromatic ring is formed is also preferable.

Further, the compound represented by the formula (3a) is a compound represented by the following formula (3b), particularly dibenzo.
It is preferably a [f, f '] diindeno [1,2,3-cd: 1', 2 ', 3'-lm] perylene derivative.

[0452]

[Chemical 256]

In formula (3b), Z _{1 to} Z ₄₄ have the same meanings as Z _{1 to} Z ₂₀ in formula (3a).

Z _{1 to} Z ₂₀ in the compound represented by the formula (3a), or Z _{1 to} Z ₄₄ in the compound represented by the formula (3b) are a substituted or unsubstituted aryl group or an alkyl group. It is preferably any one of an alkenyl group, an alkoxy group and an aryloxy group.

Further, in the compound represented by the formula (3a), Z _{1 to} Z ₂₀ , or in the compound represented by the formula (3b), at _{least one} of Z _{1 to} Z ₄₄ is an ortho-substituted phenyl group. Is preferred.

Particularly, in the compound represented by the formula (3a) or the compound represented by the formula (3b), one or both of Z ₁ and Z ₄ , and / or one of Z ₁₁ and Z ₁₄ . One or both are preferably ortho-substituted phenyl groups.

By introducing a substituent at the ortho position, the decomposability during sublimation purification can be suppressed. Further, by introducing a substituent at the ortho position, the fluorescent property is also improved.

By using such an ortho-substituted compound, the fluorescent brightness of the EL device is improved and the concentration quenching property is suppressed, so that the margin as an EL dopant is improved and the degree of freedom in design is improved.

That is, by introducing an ortho-substituted phenyl group, the steric hindrance thereof can control the associative property of the perylene skeleton, the solubility in a solvent is improved, and the purification can be performed with high purity. . Further, for the same reason, sublimation purification can be carried out at a lower temperature, decomposition during sublimation purification does not easily occur, and in this respect also, it is effective to obtain a high-purity material. When the device is manufactured, the exciton is less deactivated by impurities, and high luminous efficiency can be obtained.

Another reason why high luminous efficiency is obtained is suppression of concentration quenching by suppressing association between same molecules or different molecules in the light emitting layer.

Specific examples of the fluoranthene derivative of the present invention are shown below, but the present invention is not limited thereto. Particularly preferred specific examples of the compound represented by the formula (3b) are represented by chemical formulas 289 to 295 (G-1 to G-10).
0) and chemical formulas 313 to 317. The specific examples follow the indications of the structural formulas shown. In addition, Ph
Represents a phenyl group.

[0462]

[Chemical 257]

[0463]

[Chemical 258]

[0464]

[Chemical 259]

[0465]

[Chemical 260]

[0466]

[Chemical 261]

[0467]

[Chemical 262]

[0468]

[Chemical 263]

[0469]

[Chemical 264]

[0470]

[Chemical 265]

[0471]

[Chemical 266]

[0472]

[Chemical 267]

[0473]

[Chemical 268]

[0474]

[Chemical 269]

[0475]

[Chemical 270]

[0476]

[Chemical 271]

[0477]

[Chemical 272]

[0478]

[Chemical 273]

[0479]

[Chemical 274]

[0480]

[Chemical 275]

[0481]

[Chemical 276]

[0482]

[Chemical 277]

[0483]

[Chemical 278]

[0484]

[Chemical formula 279]

[0485]

[Chemical 280]

[0486]

[Chemical 281]

[0487]

[Chemical 282]

[0488]

[Chemical 283]

[0489]

[Chemical 284]

[0490]

[Chemical 285]

[0491]

[Chemical 286]

[0492]

[Chemical 287]

[0493]

[Chemical 288]

[0494]

[Chemical formula 289]

[0495]

[Chemical 290]

[0496]

[Chemical formula 291]

[0497]

[Chemical 292]

[0498]

[Chemical formula 293]

[0499]

[Chemical formula 294]

[0500]

[Chemical formula 295]

[0501]

[Chemical 296]

[0502]

[Chemical 297]

[0503]

[Chemical 298]

[0504]

[Chemical 299]

[0505]

[Chemical 300]

[0506]

[Chemical 301]

[0507]

[Chemical 302]

[0508]

[Chemical 303]

[0509]

[Chemical 304]

[0510]

[Chemical 305]

[0511]

[Chemical 306]

[0512]

[Chemical 307]

[0513]

[Chemical 308]

[0514]

[Chemical formula 309]

[0515]

[Chemical 310]

[0516]

[Chemical 311]

[0517]

[Chemical 312]

[0518]

[Chemical 313]

[0519]

[Chemical 314]

[0520]

[Chemical 315]

[0521]

[Chemical 316]

[0522]

[Chemical 317]

These fluoranthene derivatives may be used alone or in combination of two or more. In particular, the formula (3
The use of compounds of a) is preferred.

When such a fluoranthene derivative is used as a light emitting component in the light emitting layer, an organic EL element having high brightness and excellent durability, which has never been obtained, can be obtained. Further, the luminous efficiency is less likely to decrease due to the temperature during driving, and the temperature characteristics are excellent.

In the organic EL device of the present invention, it is preferable to use a naphthacene derivative as a host material, and in particular, a combination of a naphthacene derivative and a fluoranthene derivative is preferable, and strong light emission can be obtained.

[0526] The reason why such strong luminescence is obtained is considered to be that the naphthacene derivative and the fluoranthene derivative are an ideal combination that does not cause interaction such as exciplex formation. Further, in addition to the generation and emission of dopant excitons by the carrier trap of the dopant as described above, even when the excitons of the host are generated, the energy is efficiently transferred to the dopant and the emission mechanism in which the dopant emits light is also provided. Conceivable. The reason for such efficient host-to-dopant energy transfer in this combination is:
Since the energy gap is relatively close to that of the dopant material, an energy transfer phenomenon due to re-absorption of light emission occurs in addition to the energy transfer due to electron exchange, and it is considered that such a high emission intensity can be obtained.

Furthermore, the fact that the concentration quenching property of the dopant can be suppressed to a very small level by the combination of the above host material and the dopant also contributes to such a strong emission intensity.

Such a very good luminous efficiency when an organic EL device was produced is due to the mechanism of obtaining the above-mentioned strong fluorescence intensity, improvement of the recombination probability of carriers in the light emitting layer, and further naphthacene. It is considered that there is also an effect such as generation of a singlet excited state of the dopant by energy transfer from the triplet excited state of.

Further, in a general organic EL element, the driving voltage becomes high due to the carrier trap by the dopant, whereas the driving voltage of the organic EL element using the above light emitting layer is very low. This is because, in addition to the high carrier transportability, the above-mentioned mechanism realizes highly efficient light emission in addition to the carrier trap of the dopant. Furthermore, it may be possible to easily inject carriers into the light emitting layer. In addition, since the host has a large electron transporting property, it is considered that carriers can be localized in the dopant without a large increase in driving voltage.

Further, since the naphthacene derivative is very stable and has high durability against carrier injection, the combination of the naphthacene derivative as a host material and the fluoranthene derivative as a dopant material has a very long life.

The hole injecting and transporting layer provided in the present invention has a function of facilitating the injection of holes from the hole injecting electrode, a function of stably transporting holes and a function of hindering electrons, and is injected into the light emitting layer. It increases the holes, traps them, optimizes the recombination region and improves the luminous efficiency.

For the hole injecting and transporting layer, for example, JP-A-63-295695 and JP-A-2-19169.
4, JP-A-3-792, and JP-A-5-234.
No. 681, No. 5-239455, No. 5-299174, No. 7-126225, No. 7-126226, No. 8-100.
Various organic compounds described in Japanese Patent No. 172, EP0650955A1 and the like can be used. For example, a tetraarylbenzidine compound (triaryldiamine or triphenyldiamine: TPD), an aromatic tertiary amine, a hydrazone derivative, a carbazole derivative, a triazole derivative, an imidazole derivative, an oxadiazole derivative having an amino group, polythiophene, and the like. . Two or more of these compounds may be used in combination, and when they are used in combination, they may be laminated in different layers or mixed.

The hole injecting and transporting layer may be divided into a hole injecting layer and a hole transporting layer, and in this case, a preferable combination can be selected and used from the compounds for the hole injecting and transporting layer. . At this time, it is preferable to stack layers of a compound having a small ionization potential in this order from the hole injection electrode (ITO or the like) side. Further, it is preferable to use a compound having a good thin film property on the surface of the hole injecting electrode. This stacking order is the same when two or more hole injecting and transporting layers are provided. By adopting such a stacking order, the driving voltage is lowered, and it is possible to prevent the occurrence of current leakage and the generation / growth of dark spots. In addition, when forming an element, since vapor deposition is used,
Even a thin film of about 10 nm can be made uniform and pinhole-free, so even if a compound with a small ionization potential and absorption in the visible region is used for the hole injection layer, changes in the color tone of the emission color and reabsorption are possible. It is possible to prevent a decrease in efficiency due to.

The thickness of the hole injecting and transporting layer depends on the design of the recombination / light emitting region, but is about the same as that of the light emitting layer or 1
It may be about / 10 to 10 times. The thickness of the hole injecting and transporting layer is not particularly limited, and depends on the forming method,
Usually, it is preferably about 5 to 500 nm, particularly preferably 10 to 300 nm. When the injection layer and the transport layer are separated, it is preferable that the injection layer has a thickness of 1 nm or more and the transport layer has a thickness of 1 nm or more. At this time, the upper limits of the thickness of the injection layer and the transport layer are usually about 500 nm for the injection layer and about 500 nm for the transport layer. Such a film thickness is the same when two injecting and transporting layers are provided.

For forming the electron injecting layer, the electron transporting layer, the light emitting layer and the hole injecting and transporting layer, it is preferable to use the vacuum deposition method because a uniform thin film can be formed. When the vacuum deposition method is used, the amorphous state or the crystal grain size is 0.
A homogeneous thin film of 1 μm or less is obtained. Crystal grain size is 0.1
If it exceeds μm, the light emission becomes non-uniform, the driving voltage of the device must be increased, and the hole injection efficiency is significantly reduced.

The conditions of vacuum vapor deposition are not particularly limited, but 1
The degree of vacuum is 0 ^-4 Pa or less, and the deposition rate is 0.01 to 1 nm /
It is preferably about sec. Moreover, it is preferable to form each layer continuously in a vacuum. If they are continuously formed in a vacuum, it is possible to prevent impurities from adsorbing to the interface of each layer, so that high characteristics can be obtained. Further, it is possible to lower the driving voltage of the element and suppress the growth / occurrence of dark spots.

When a vacuum vapor deposition method is used to form each of these layers, when a plurality of compounds are contained in one layer, it is preferable to co-evaporate the boats containing the compounds by individually controlling the temperature.

As a method for forming the mixed layer in the light emitting layer, co-evaporation in which evaporation is performed from different evaporation sources is preferable. However, when vapor pressures (evaporation temperatures) are about the same or very close, it is necessary to preliminarily use the same evaporation board. It is also possible to deposit them by mixing with. Although it is preferable that the compounds are uniformly mixed in the mixed layer, the compounds may exist in an island shape in some cases.

The electron injection electrode (cathode) is preferably composed of a metal, alloy or intermetallic compound having a work function of 4 eV or less. When the work function exceeds 4 eV, the electron injection efficiency decreases, and the light emission efficiency also decreases. Work function is 4
As the constituent metal of the electron injection electrode film of eV or less, for example,
Alkali metals such as Li, Na, K, Mg, Ca, Sr,
Examples thereof include alkaline earth metals such as Ba, rare earth metals such as La and Ce, and Al, In, Ag, Sn, Zn, Zr. As a constituent alloy of a film having a work function of 4 eV or less, for example, Ag.Mg (Ag: atomic ratio of 0.1 to 50%), A
l·Li (Li: atomic ratio of 0.01 to 12%), In ·
Mg (Mg: 50-80% in atomic ratio), Al-Ca (C
a: 0.01 to 20% by atomic ratio) and the like. These may be present alone or as a combination of two or more kinds, and in the case of combining two or more kinds, the mixing ratio is arbitrary. In addition, thin films of oxides and halides of alkali metals, alkaline earth metals, and rare earth metals,
A supporting electrode (auxiliary electrode, wiring electrode) such as aluminum may be used.

This electron injection electrode can be formed by a vapor deposition method, a sputtering method or the like.

The thickness of such an electron injecting electrode may be a certain thickness or more for sufficiently injecting electrons, and is 0.1 nm.
The above is sufficient. The upper limit value is not particularly limited, but the film thickness is usually about 0.1 to 500 nm.

As the hole injecting electrode (anode), it is preferable to determine the material and thickness so that the transmittance of emitted light is 80% or more. Specifically, an oxide transparent conductive thin film is preferable, and examples thereof include tin-doped indium oxide (ITO) and zinc-doped indium oxide (IZ).
O), indium oxide (In ₂ O ₃ ), tin oxide (Sn)
It is preferable that the main composition is either O ₂ ) or zinc oxide (ZnO). These oxides may deviate somewhat from their stoichiometric composition. Sn for In ₂ O ₃
The mixing ratio of O ₂ is preferably 1 to 20% (mass percentage), and more preferably 5 to 12% (mass percentage). I
The mixing ratio of ZnO to n ₂ O ₃ is preferably 12 to 32% (mass percentage).

The hole injecting electrode has an emission wavelength band, usually 3
50 ~ 800nm, especially the light transmittance for each emitted light is 80
% Or more, particularly preferably 90% or more. Normal,
Since the emitted light is extracted through the hole injecting electrode, if the transmittance thereof is low, the light emission itself from the light emitting layer is attenuated, and the luminance required as a light emitting element tends to be not obtained. However, it is sufficient that the side from which emitted light is extracted is 80% or more.

The thickness of the hole injecting electrode may be a certain thickness or more capable of sufficiently injecting holes, preferably 5
The range of 0 to 500 nm, preferably 50 to 300 nm is preferable. The upper limit is not particularly limited, but if it is too thick, peeling or the like may occur. If the thickness is too thin, there are problems in film strength during production, hole transport ability, and resistance value.

A sputtering method is preferable for forming the hole injecting electrode. As the sputtering method, a high frequency sputtering method using an RF power source or the like is possible, but the DC sputtering method is used in consideration of the ease of controlling the film physical properties of the hole injection electrode for film formation, the smoothness of the film formation surface, and the like. It is preferable.

A protective film may be formed if necessary. The protective film can be formed using an inorganic material such as SiO _X or an organic material such as Teflon (registered trademark). The protective film may be transparent or opaque, and the thickness of the protective film is about 50 to 1200 nm. In addition to the reactive sputtering method described above, the protective film may be formed by a general sputtering method, vapor deposition method, or the like.

Furthermore, it is preferable to provide a sealing layer on the element in order to prevent oxidation of the organic layers and electrodes of the element. The sealing layer is an adhesive resin layer such as a commercially available low hygroscopic photocurable adhesive, an epoxy adhesive, a silicone adhesive, a crosslinked ethylene-vinyl acetate copolymer adhesive sheet, etc. for preventing the invasion of moisture. Using, the sealing plate such as a glass plate is adhered and sealed. Besides the glass plate, a metal plate, a plastic plate or the like can be used.

As the substrate material, a transparent or translucent material such as glass, quartz, or resin is used when the light emitted from the substrate side is taken out. Further, the substrate may be provided with a color filter film, a color conversion film containing a fluorescent substance, or a dielectric reflection film to control the emission color. In the case of the reverse lamination, the substrate may be transparent or opaque, and if opaque, ceramics or the like may be used.

As the color filter film, a color filter used in a liquid crystal display or the like may be used, but the characteristics of the color filter are adjusted according to the light emitted by the organic EL to optimize the extraction efficiency and color purity. do it. In addition, if a color filter capable of blocking external light of a short wavelength that is absorbed by the EL device material or the fluorescence conversion layer is used, the light resistance of the device and the display contrast are also improved. Further, an optical thin film such as a dielectric multilayer film may be used to replace the color filter.

The organic EL device of the present invention is usually used as a DC drive type or pulse drive type EL device, but it may be an AC drive type. The applied voltage is usually 2 to 30.
It is about V.

[0551]

EXAMPLES The present invention will be specifically described below with reference to examples. A comparative example is also shown. The compounds used in the following Examples and Comparative Examples are shown below.

[0552]

[Chemical 318]

[0553]

[Chemical 319]

Example 1 A glass substrate with an ITO transparent electrode was subjected to ultrasonic cleaning with a neutral detergent, acetone and ethanol, pulled out from boiling ethanol and dried. UV / O _{3 on the} transparent electrode surface
After cleaning, fix it on the substrate holder of the vacuum evaporation system,
The pressure inside the tank was reduced to 1 × 10 ⁻⁴ Pa or less. Then, while maintaining the reduced pressure state, N, N′-diphenyl-N, N′-bis [N- (4-methylphenyl)-
N-phenyl- (4-aminophenyl)]-1,1'-
Biphenyl-4,4'-diamine vapor deposition rate 0.1 nm / s
It was deposited by ec to a film thickness of 60 nm. Then, N, N, N ′, N′-tetrakis (m-biphenyl) -1,1′-biphenyl-4,4′-diamine was deposited as a hole transport layer at a deposition rate of 0.1 nm / sec to a thickness of 10 nm. It was deposited on.

[0555] Further, while maintaining the reduced pressure, the compound I (Naph) as the host material and the compound II as the dopant material were used.
(Indenoperylene) was vapor-deposited at a mass ratio of 99: 1 at a total vapor deposition rate of 0.15 to 0.20 nm / sec to a thickness of 40 nm to obtain a light emitting layer.

Then, the compound I (N
aph) was vapor deposited at a vapor deposition rate of 0.1 nm / sec to a thickness of 25 nm to form an electron transport layer.

Further, while maintaining the reduced pressure, the compound II
I (B-phen) was evaporated at a deposition rate of 0.1 nm / sec to a thickness of 5 nm to form an electron injection layer.

Then, LiF is vapor-deposited at a rate of 0.01 nm / sec.
Was evaporated to a thickness of 0.3 nm as an electron injection electrode and Al as a protective electrode to a thickness of 150 nm to obtain an organic EL device.

A direct current voltage was applied to this organic EL device, and at the initial stage, the current density was 10 mA / c ² and the driving voltage was 3.9 V.
Light emission of 660 cd / m ² was confirmed. At this time, the maximum emission wavelength λmax = 610 nm and the chromaticity coordinates are (x, y) = (0.
66, 0.34). The efficiency at this time is 5.3 1
It was m / W.

When a constant current of 50 mA / cm ² was passed through this element to cause continuous light emission, the initial luminance was 3100 cd / m ^2.
Then, the luminance attenuation after 2000 hours was 15%.

Examples 2 to 5 and Comparative Examples 1 to 4 In the organic EL devices of Example 1, the compounds used for the electron transport layer and the electron injection layer were changed as shown in Table 1, respectively, and otherwise the same. An organic EL device was obtained. About these, the characteristics were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1 together with Example 1.

The dipole moments of the electron transporting materials shown in Table 1 are calculated according to the semiempirical molecular orbital method program (MO
PAC). The dipole moment of Compound I, which is the host material of the light emitting layer, is also the same.

The ionization potential (IP) of the electron transport layer and the light emitting layer was measured by atmospheric photoelectron spectroscopy or cyclic voltammetry, and the difference was calculated and shown in Table 1.

Further, the electron transporting property μ _a of the electron transporting layer is
The driving voltage (V) required to pass a current of 100 mA / cm ² was obtained by forming devices with electron transport layers having film thicknesses of 25 nm and 60 nm, and calculated from the above relational expression. Among these, Table 2 shows the values of the driving voltage (V) when the film thickness was changed in Example 1 and Comparative Example 2.

[0565]

[Table 1]

[0566]

[Table 2]

Also in Examples 2 to 5, λmax and chromaticity coordinates are almost the same as in Example 1, and Comparative Examples 2, 3
Then, since the electron transport layer emits light, (x, y) =
(0.65, 0.35), and in Comparative Example 1, Example 1
Was similar to.

Example 6 An element obtained by changing the thickness of the electron injection layer as shown in Table 3 in Example 1 while keeping the total thickness of the electron transport layer and the electron injection layer at 30 nm was obtained. . These are sample No. 1
-1 to No. 1 to 7. Sample No. 1-5 is the same as that of the first embodiment. Table 3 shows the results of evaluating the initial characteristics of these in the same manner as in Example 1. Further, FIG. 1 shows the relationship between the driving voltage and the thickness of the electron injection layer.

[0569]

[Table 3]

Comparative Example 5 Compound VI (Alq) was used as the host material of the light emitting layer, compound IX (pyran) was used as the dopant material, and the compound was used as the electron transport material.
A device was prepared and evaluated in the same manner as in Example 1 except that VI (Alq) was used. The results are shown below.

Initial characteristics at 10 mA / cm ² driving Driving voltage: 8.2 V Luminance: 380 cd / m ² Efficiency: 1.58 lm / W Continuous driving characteristics: Half at 1000 hr

The chromaticity coordinate is (x, y) = (0.6
1, 0.39). Note that μ _{a of the} electron transport layer is 1
The dipole moment was 9.4 nm / V, the dipole moment was 6.57 Debye, and the Ip difference from the light emitting layer was 0 eV.

[0573]

In the constitution of the present invention, a material having excellent adhesion to an electrode or an electron transport layer is used for the electron injection layer, and a material having a high electron transport property is used for the electron transport layer. Electrons can be efficiently transported, low voltage driving can be performed, and high luminous efficiency with respect to current density can be obtained. Further, the voltage change is small when the film thickness of the electron transport layer is changed, and the optical film thickness can be adjusted without increasing the voltage. Therefore, high external extraction efficiency can be obtained. Further, it is possible to obtain a device of high color purity in which light is hardly emitted from the electron transport layer. Further, it is possible to obtain a highly durable and long-life element in which the driving voltage rise and the luminance drop during continuous driving are extremely small.

[Brief description of drawings]

FIG. 1 is a graph showing a relationship between a driving voltage and a thickness of an electron injection layer.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09K 11/06 645 C09K 11/06 645 650 650 650 690 690 H05B 33/14 H05B 33/14 B (72) Inventor Hiromitsu Ogawa 1-13-1, Nihonbashi, Chuo-ku, Tokyo F-term inside TDC Corporation (reference) 3K007 AB03 AB04 AB06 AB11 DB03

Claims (27)

[Claims] 1. An organic EL device having a structure in which at least one light emitting layer, an electron transport layer, and an electron injection layer are sequentially stacked from the anode side, wherein the electron transport layer is a naphthacene derivative and / or an anthracene derivative. An organic EL device containing: 2. The organic EL device according to claim 1, which has at least one hole injecting and transporting layer on the anode side of the light emitting layer. 3. The organic EL device according to claim 1, wherein the electron injection layer contains an organic compound. 4. The organic EL device according to claim 1, wherein the electron injection layer has a thickness of 0.6 to 20 nm. 5. The organic EL device according to claim 4, wherein the electron injection layer has a thickness of 1 to 10 nm. 6. The organic EL device according to claim 1, wherein the electron injection layer contains a heterocyclic compound. 7. The organic EL device according to claim 1, wherein the electron injection layer contains a nitrogen-containing heterocyclic compound. 8. The electron injection layer is 1,10-phenanthroline,
1,9-phenanthroline, 1,8-phenanthroline, 1,7-phenanthroline, 2,9-phenanthroline, 2,8-phenanthroline, 2,7-phenanthroline, 3,8-phenanthroline, 3,7-phenanthroline, 4, The organic EL device according to any one of claims 1 to 7, which contains at least one kind of phenanthroline derivative having 7-phenanthroline and one or more of these phenanthroline skeletons in a molecule. 9. The organic EL device according to claim 8, wherein the phenanthroline or phenanthroline derivative contained in the electron injection layer is represented by the following formula (1a) or formula (1b). [Chemical 1] [In the formula (1a), Y _{2 to} Y ₉ may be the same or different and each represents hydrogen, an aryl group, an alkyl group,
It represents an aralkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkenyl group, an amino group or a heterocyclic group, and two or more of these adjacent groups may be bonded to each other to form a ring. In formula (1b), A and B, which may be the same or different, each represents a group represented by formula (1c), and L represents a single bond or a divalent linking group. In formula (1c), Y _{12 to} Y ₁₉ may be the same or different, and Y ₁₂ in formula (1a)
_{It has the same} meaning as _{2 to} Y ₉ . However, Y in formula (1c)
One of the ₁₂ to Y _19, which constitutes the L, Y ₁₂ to Y ₁₉ constituting L may be different even if the same in A and B. ] 10. The organic EL device according to claim 1, wherein the electron transport layer contains a naphthacene derivative. 11. The organic EL device according to claim 10, wherein the naphthacene derivative contained in the electron transport layer is represented by the following formula (2). [Chemical 2] [In the formula (2), Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ , Q ⁵⁰ , Q ⁶⁰ ,
^{Q 70, Q 80, Q 110} , Q 1 20, Q 130 and Q ¹⁴⁰ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group, or It represents a heterocyclic group, which may be the same or different. ] 12. The naphthacene derivative represented by the formula (2) contained in the electron transport layer has Q ¹⁰ , Q ²⁰ , Q ³⁰ , and Q.
The organic EL device according to claim 11, wherein at least one of ⁴⁰ , Q ⁵⁰ , Q ⁶⁰ , Q ⁷⁰ and Q ⁸⁰ is an aryl group. 13. A naphthacene derivative represented by the formula (2) contained in the electron transporting layer, wherein Q ¹⁰ , Q ²⁰ and Q ³⁰ are contained.
13. The organic EL device according to claim 11 or 12, wherein at least one of Q ⁴⁰ is an aryl group. 14. The organic EL device according to claim 9, wherein the naphthacene derivative contained in the electron transport layer is represented by the following formula (2a). [Chemical 3] [In the formula (2a), Q ^{5 to} Q ⁸ and Q ^{11 to} Q ¹⁶ are each hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkenyl group, an aralkyl group or It represents a heterocyclic group, which may be the same or different. Q ²¹
To Q ²⁵ and Q ^{51 to} Q ⁵⁵ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, and these are They may be the same or different, and two or more adjacent to each other may combine with each other to form a ring. ] 15. The organic EL device according to claim 9, wherein the naphthacene derivative contained in the electron transport layer is a hydrocarbon compound. 16. The organic EL device according to claim 1, wherein the light emitting layer contains a host material and a dopant material, and the host material contains a naphthacene derivative. 17. The organic EL device according to claim 16, wherein the naphthacene derivative contained in the light emitting layer is represented by the following formula (2). [Chemical 4] [In the formula (2), Q ¹⁰ , Q ²⁰ , Q ³⁰ , Q ⁴⁰ , Q ⁵⁰ , Q ⁶⁰ ,
^{Q 70, Q 80, Q 110} , Q 1 20, Q 130 and Q ¹⁴⁰ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group, or It represents a heterocyclic group, which may be the same or different. ] 18. A naphthacene derivative represented by the formula (2) contained in the light emitting layer, wherein Q ¹⁰ , Q ²⁰ , Q ³⁰ , and Q are included.
^At least one of ⁴⁰ , Q ⁵⁰ , Q ⁶⁰ , Q ⁷⁰ and Q ⁸⁰
18. The organic EL device according to claim 17, wherein at least one is an aryl group. 19. The organic compound according to claim 17, wherein at least one of Q ¹⁰ , Q ²⁰ , Q ³⁰ and Q ^{40 in} the naphthacene derivative represented by the formula (2) contained in the light emitting layer is an aryl group. EL element. 20. The naphthacene derivative contained in the host material of the light emitting layer is represented by the following formula (2a):
9. The organic EL device according to any one of 9. [Chemical 5] [In the formula (2a), Q ^{5 to} Q ⁸ and Q ^{11 to} Q ¹⁶ are each hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an alkenyl group, an aralkyl group or It represents a heterocyclic group, which may be the same or different. Q ²¹
To Q ²⁵ and Q ^{51 to} Q ⁵⁵ each represent hydrogen, an alkyl group, an aryl group, an amino group, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an alkenyl group, an aralkyl group or a heterocyclic group, and these are They may be the same or different, and two or more adjacent to each other may combine with each other to form a ring. ] 21. The organic EL device according to claim 16, wherein the naphthacene derivative contained in the light emitting layer is a hydrocarbon compound. 22. The organic EL device according to claim 16, wherein the dopant material of the light emitting layer contains a fluoranthene derivative. 23. A fluoranthene derivative represented by the following formula (3)
3. The indenoperylene derivative represented by a).
2 organic EL elements. [Chemical 6] Wherein _{(3a), Z 1 ~Z 6} , Z 9, Z 10, Z 11 ~Z 16,
Z ₁₉ and Z ₂₀ are each hydrogen, halogen, alkyl group, alkoxy group, alkylthio group, alkenyl group, alkenyloxy group, alkenylthio group, aromatic ring-containing alkyl group, aromatic ring-containing alkyloxy group, aromatic ring-containing alkylthio group. , Aromatic ring group, aromatic ring oxy group, aromatic ring thio group, aromatic ring alkenyl group, alkenyl aromatic ring group, amino group, cyano group, hydroxyl group, -COOR ₁ (wherein R ₁ is hydrogen, an alkyl group, an alkenyl group , An aromatic ring-containing alkyl group or an aromatic ring group), —COR ₂ (wherein R ₂ represents hydrogen, an alkyl group, an alkenyl group, an aromatic ring-containing alkyl group, an aromatic ring group or an amino group), or — OCO
R ₃ (wherein R ₃ represents an alkyl group, an alkenyl group, an aromatic ring-containing alkyl group or an aromatic ring group), and further Z _{1 to} Z ₆ , Z ₉ , Z ₁₀ , Z _{11 to} Z ₁₆ , Z ₁₉ , Z ₂₀
Among them, adjacent groups may be bonded to each other to form a ring with the carbon atom which is substituted. ] 24. The organic EL device according to claim 1, wherein an electron transporting property μ _a defined below of the electron transporting layer is 80 nm / V or more (wherein the electron transporting property μ _a is In the organic EL device of No. 1, the electron transport layer is a parameter defined as follows by the change of the driving voltage required to flow a current of 100 mA / cm ² when the thickness of the electron transport layer is changed. Thickness (nm) of d ₁ , d ₂ (where d ₁ >
When the driving voltage (V) at the time of driving 100 mA / cm ² when d ₂ ) is V ₁ and V ₂ , respectively, μ _a = (d ₁ −
d ₂ ) / (V ₁ −V ₂ )). 25. The difference in the value of ionization potential between the electron transport layer and the light emitting layer is 0.1 eV or less.
Any one of the organic EL elements. 26. The value of the dipole moment of the material used for the electron transport layer is 1.0 Debye or less.
5. The organic EL element of any one of 5. 27. The light emitting layer contains a host material and a dopant material, and the host material has a dipole moment value of 1.
27. The organic EL element according to claim 16, which is 0 Debye or less.