TWI765996B - Compound, electronic device containing same, organic thin-film light-emitting device, display device, and lighting device - Google Patents

Abstract

An object of the present invention is to provide an organic thin-film light-emitting element having improved all properties of luminous efficiency, driving voltage, and durable life. The present invention is a specific compound containing a quinazoline skeleton.

Description

Compound, electronic device containing same, organic thin-film light-emitting device, display device, and lighting device

The present invention relates to a compound, an electronic device containing the same, an organic thin-film light-emitting device, a display device and a lighting device.

The organic thin-film light-emitting element is an element that emits light when electrons injected from the cathode and holes injected from the anode recombine within an organic phosphor sandwiched between the two electrodes. Research on this organic thin-film light-emitting element has been actively conducted in recent years. The organic thin-film light-emitting element is characterized by being thin, capable of obtaining high-brightness light emission at a low driving voltage, and realizing multicolor light emission by appropriately selecting a light-emitting material such as a fluorescent light-emitting material or a phosphorescent light-emitting material.

Organic thin-film light-emitting elements have been practically advanced in recent years, and have been used in main displays of mobile phones and the like. However, there are still many technical problems in existing organic thin-film light-emitting devices. Among them, the achievement of high-efficiency light emission and the longevity of the organic thin-film light-emitting element have become a major problem.

As a compound to solve these problems, a compound in which a carbazole skeleton is linked to a quinazoline skeleton, which is a heteroaromatic ring containing a nitrogen atom (hereinafter referred to as "nitrogen-containing aromatic heterocycle"), has been developed (for example, refer to Patent Documents). 1 to Patent Document 2, Non-Patent Document 1).

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] International Publication No. 2006/049013

[Patent Document 2] Japanese Patent Publication No. 2016-508131

[Non-patent literature]

[Non-Patent Document 1] "Dyes and Pigments" 125 (2016) 299

However, in the compounds described in Patent Document 1, Patent Document 2, or Non-Patent Document 1, it is difficult to sufficiently reduce the driving voltage of the organic thin-film light-emitting element. In addition, even if the driving voltage can be lowered, the luminous efficiency and durable life of the organic thin-film light-emitting element are not sufficient. In this way, a technology that exhibits excellent performance in all of luminous efficiency, driving voltage, and durability life has not yet been found.

An object of the present invention is to solve the problems of the prior art, and to provide an organic thin-film light-emitting element with improved luminous efficiency, driving voltage, and durability.

The present invention is a compound represented by the following general formula (1).

[hua 1]

In formula (1), L ¹ and L ² are single bonds, or substituted or unsubstituted arylidene groups, or substituted or unsubstituted heteroarylidene groups. L ¹ is connected at any position of X ¹ to X ⁸ and R ⁵⁵ , and L ² is connected at any position of X ⁹ to X ¹⁶ and R ⁵⁶ . Among them, the case where L ¹ is connected at the position of R ⁵⁵ and L ² is connected at the position of R ⁵⁶ is excluded.

Either L ¹ or L ² must be a substituted or unsubstituted arylidene group, or a substituted or unsubstituted heteroarylidene group.

R ⁵¹ to R ⁵⁴ are independently selected from a hydrogen atom, an alkyl group, a cycloalkyl group, a heterocyclic group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an alkoxy group, an alkylthio group, an aryl ether group, and an aryl sulfur group In the group consisting of ether group, aryl group, heteroaryl group, halogen atom, cyano group, amino group, carbonyl group, carboxyl group, oxycarbonyl group, carboxyl group and -P(=O)R ⁵⁷ R ⁵⁸ .

R ⁵⁷ and R ⁵⁸ are aryl groups or heteroaryl groups, and R ⁵⁷ and R ⁵⁸ may be condensed to form a ring.

R ⁵⁵ and R ⁵⁶ are selected from the group consisting of a hydrogen atom, an alkyl group, a cycloalkyl group, a heterocyclic group, an alkenyl group, a cycloalkenyl group, an aryl group and a heteroaryl group.

X ⁿ (n=1~16) are CR ⁿ (n=1~16) or nitrogen atoms, respectively.

R ⁿ (n=1~16) are independently selected from hydrogen atom, alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl ether group, arylthio group In the group consisting of ether group, halogen atom, cyano group, amine group, carbonyl group, carboxyl group, oxycarbonyl group, carboxyl group and -P(=O)R ¹⁷ R ¹⁸ .

R ¹⁷ and R ¹⁸ are aryl groups or heteroaryl groups, and R ¹⁷ and R ¹⁸ may be condensed to form a ring.

According to the present invention, it is possible to provide an organic thin-film light-emitting element excellent in high luminous efficiency, low driving voltage, and long durability.

Hereinafter, preferred embodiments of the compound of the present invention, an electronic device containing the same, a display device, and a lighting device will be described in detail. However, the present invention is not limited to the following embodiments, and can be implemented with various modifications according to the purpose and application.

<The compound represented by the general formula (1)>

The compound represented by General formula (1) which is one Embodiment of this invention is shown below.

[hua 2]

In formula (1), L ¹ and L ² are single bonds, or substituted or unsubstituted arylidene groups, or substituted or unsubstituted heteroarylidene groups. L ¹ is connected at any position of X ¹ to X ⁸ and R ⁵⁵ , and L ² is connected at any position of X ⁹ to X ¹⁶ and R ⁵⁶ . Among them, the case where L ¹ is connected at the position of R ⁵⁵ and L ² is connected at the position of R ⁵⁶ is excluded.

Either L ¹ or L ² must be a substituted or unsubstituted arylidene group, or a substituted or unsubstituted heteroarylidene group.

R ⁵¹ to R ⁵⁴ are independently selected from a hydrogen atom, an alkyl group, a cycloalkyl group, a heterocyclic group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an alkoxy group, an alkylthio group, an aryl ether group, and an aryl sulfur group In the group consisting of ether group, aryl group, heteroaryl group, halogen atom, cyano group, amino group, carbonyl group, carboxyl group, oxycarbonyl group, carboxyl group and -P(=O)R ⁵⁷ R ⁵⁸ .

R ⁵⁷ and R ⁵⁸ are aryl groups or heteroaryl groups, and R ⁵⁷ and R ⁵⁸ may be condensed to form a ring.

R ⁵⁵ and R ⁵⁶ are selected from the group consisting of a hydrogen atom, an alkyl group, a cycloalkyl group, a heterocyclic group, an alkenyl group, a cycloalkenyl group, an aryl group and a heteroaryl group.

X ⁿ (n=1~16) are CR ⁿ (n=1~16) or nitrogen atoms, respectively.

R ⁿ (n=1~16) are independently selected from hydrogen atom, alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl ether group, arylthio group In the group consisting of ether group, halogen atom, cyano group, amine group, carbonyl group, carboxyl group, oxycarbonyl group, carboxyl group and -P(=O)R ¹⁷ R ¹⁸ .

R ¹⁷ and R ¹⁸ are aryl groups or heteroaryl groups, and R ¹⁷ and R ¹⁸ may be condensed to form a ring.

In all the groups, hydrogen may be deuterium. In addition, in the following description, for example, the so-called substituted or unsubstituted aryl group having 6 to 40 carbon atoms means that the number of carbons included in the substituent substituted in the aryl group is 6 to 6 40. The same applies to other substituents whose carbon number is specified.

In addition, the substituent when referring to "substituted or unsubstituted" is preferably an alkyl group, a cycloalkyl group, a heterocyclyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an alkoxy group, an alkane group as described above A thio group, an aryl ether group, an aryl sulfide group, an aryl group, a heteroaryl group, a halogen atom, a cyano group, an amino group, a carbonyl group, a carboxyl group, an oxycarbonyl group, an amine carboxyl group, and more preferably the Preferred specific substituents in the description. In addition, these substituents may be further substituted with the substituents.

In the compounds described below or their partial structures, the "substituted or unsubstituted" is also the same as described above.

The alkyl group represents, for example, a saturated aliphatic hydrocarbon group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, and tert-butyl. The alkyl group may or may not have a substituent. The additional substituent when the alkyl group is substituted is not particularly limited, and examples thereof include an alkyl group, an aryl group, a heteroaryl group, and the like, and this aspect is also common to the description below. In addition, the number of carbon atoms of the alkyl group is not particularly limited, and the ease of obtaining or the From the viewpoint of cost, the range of 1 or more and 20 or less is preferable, and the range of 1 or more and 8 or less is more preferable.

The cycloalkyl group means, for example, a saturated alicyclic hydrocarbon group such as a cyclopropyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group. The cycloalkyl group may or may not have a substituent. The number of carbon atoms in the alkyl moiety of the cycloalkyl group is not particularly limited, but is preferably in the range of 3 or more and 20 or less.

The heterocyclic group refers to, for example, a pyran ring, a piperidine ring, a cyclic amide and an aliphatic ring having an atom other than carbon in the ring. The heterocyclic group may or may not have a substituent. The heterocyclic ring may have one or more double bonds in the ring as long as it does not have aromaticity. The number of carbon atoms in the heterocyclic group is not particularly limited, but is preferably in the range of 2 or more and 20 or less.

The alkenyl group means, for example, an unsaturated aliphatic hydrocarbon group including a double bond, such as a vinyl group, an allyl group, and a butadienyl group. The alkenyl group may or may not have a substituent. The number of carbon atoms in the alkenyl group is not particularly limited, but is preferably in the range of 2 or more and 20 or less.

The cycloalkenyl group means, for example, an unsaturated alicyclic hydrocarbon group containing a double bond, such as a cyclopentenyl group, a cyclopentadienyl group, and a cyclohexenyl group. The cycloalkenyl group may or may not have a substituent. The number of carbon atoms in the cycloalkenyl group is not particularly limited, but is preferably in the range of 4 or more and 20 or less.

The alkynyl group means, for example, an unsaturated aliphatic hydrocarbon group including a triple bond such as an ethynyl group. The alkynyl group may or may not have a substituent. The number of carbon atoms in the alkynyl group is not particularly limited, but is preferably in the range of 2 or more and 20 or less.

The term "alkoxy" refers to, for example, aliphatic such as a methoxy group, an ethoxy group, and a propoxy group. A functional group in which a hydrocarbon group is bonded via an ether bond. The aliphatic hydrocarbon group may or may not have a substituent. Although the carbon number of an alkoxy group is not specifically limited, It is preferable that it is the range of 1 or more and 20 or less.

The alkylthio group is one in which the oxygen atom of the ether bond of the alkoxy group is substituted with a sulfur atom. The hydrocarbon group of the alkylthio group may or may not have a substituent. The number of carbon atoms in the alkylthio group is not particularly limited, but is preferably in the range of 1 or more and 20 or less.

The aryl ether group means, for example, a functional group in which an aromatic hydrocarbon group such as a phenoxy group is bonded via an ether bond. The aromatic hydrocarbon group may or may not have a substituent. The number of carbon atoms in the aryl ether group is not particularly limited, but is preferably in the range of 6 or more and 40 or less.

The aryl sulfide group is one in which the oxygen atom of the ether bond of the aryl ether group is substituted with a sulfur atom. The aromatic hydrocarbon group in the aryl sulfide group may or may not have a substituent. The number of carbon atoms in the aryl sulfide group is not particularly limited, but is preferably in the range of 6 or more and 40 or less.

The aryl group represents, for example, an aromatic hydrocarbon group such as a phenyl group, a naphthyl group, a biphenyl group, a triphenyl group, a phenanthryl group, an anthracenyl group, a pyrenyl group, and a prop[di]enyl fluoranthenyl group. The aryl group may or may not have a substituent. The number of carbon atoms in the aryl group is not particularly limited, but is preferably in the range of 6 or more and 40 or less, and more preferably in the range of 6 or more and 24 or less. Specific examples of the aryl group are preferably a phenyl group, a 1-naphthyl group, and a 2-naphthyl group.

The so-called heteroaryl group means furyl, thienyl, pyridyl, quinolyl, isoquinolyl, pyrazinyl, pyrimidinyl, naphthyridinyl, benzofuranyl, benzothienyl, indolyl, di Benzofuranyl, dibenzothienyl, carbazolyl, etc. in one or more A cyclic aromatic group having atoms other than carbon in the ring. The heteroaryl group may or may not have a substituent. The number of carbon atoms in the heteroaryl group is not particularly limited, but is preferably in the range of 2 or more and 30 or less. Specific examples of the heteroaryl group are preferably a pyridyl group, a quinolyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothienyl group.

The amine group refers to a substituted or unsubstituted amine group. As a substituent at the time of substitution, an aryl group, a heteroaryl group, a straight-chain alkyl group, and a branched alkyl group are mentioned, for example. More specifically, a phenyl group, a biphenyl group, a naphthyl group, a pyridyl group, a methyl group, etc. may be mentioned, and these substituents may be further substituted. The carbon number of the substituent is not particularly limited, but is preferably in the range of 6 or more and 40 or less.

The halogen atom means an atom selected from fluorine, chlorine, bromine and iodine.

A carbonyl group, a carboxyl group, an oxycarbonyl group, a carboxyl group, and a phosphine oxide group may or may not have a substituent. Here, as a substituent, an alkyl group, a cycloalkyl group, an aryl group, a heteroaryl group, etc. are mentioned, for example, These substituents may be substituted further.

The aryl extended group means a divalent or higher group derived from aromatic hydrocarbons such as benzene, naphthalene, biphenyl, phenylene, and phenanthrene. The arylidene group may or may not have a substituent. Preferred arylidene groups are divalent or trivalent arylidene groups. Specific examples of the arylidene group include a phenylene group, a biphenylene group, a naphthylene group, a perylene group, and the like. More specifically, 1,4-phenylene, 1,3-phenylene, 1,2-phenylene, 4,4'-biphenylene, 4,3'-biphenylene, 3 ,3'-biphenylene, 1,4-naphthylene, 1,5-naphthylene, 2,5-naphthylene, 2,6-naphthylene, 2,7-naphthylene, 1 , 3,5-phenylene and so on. More preferred are 1,4-phenylene, 1,3-phenylene, 4,4'-biphenylene, and 4,3'-biphenylene.

The so-called extended heteroaryl group is represented by pyridine, quinoline, pyrimidine, pyrazine, triazine, A divalent or higher group derived from an aromatic group having atoms other than carbon in one or more rings, such as quinoxaline, quinazoline, dibenzofuran, and dibenzothiophene. The heteroaryl group may or may not have a substituent. Preferred heteroaryl groups are divalent or trivalent heteroaryl groups. The number of carbon atoms in the heteroaryl group is not particularly limited, but is preferably in the range of 2 or more and 30 or less. Specific examples of the heteroaryl group include: 2,6-pyridylene, 2,5-pyridyl, 2,4-pyridyl, 3,5-pyridyl, 3,6-pyridyl, Pyridinyl Triazinyl, 4,6-dibenzofuranyl, 2,6-dibenzofuranyl, 2,8-dibenzofuranyl, 3,7-dibenzofuranyl and the like.

The quinazoline skeleton has two nitrogen atoms with high electronegativity and forming sp ² mixed orbitals, so it has high affinity with electrons and high electron transport properties. Therefore, when a compound having a quinazoline skeleton is used for the electron injection layer of an organic thin-film light-emitting element, electron injection from the cathode to the electron injection layer is likely to occur.

In addition, when a compound having a quinazoline skeleton is used for an electron transport layer of an organic thin-film light-emitting element, the electron transport layer exhibits high electron transport properties. However, in a common organic thin-film light-emitting device, the LUMO energy level of a molecule containing only a quinazoline skeleton is too low compared to the lowest unoccupied molecular orbital (LUMO) energy level of the light-emitting layer. Therefore, injection of electrons from the electron transport layer to the light emitting layer is hindered.

Therefore, a carbazole skeleton is introduced into the compound represented by the general formula (1). The reason for this is that the carbazole skeleton has a property of increasing the LUMO level or good electron transport properties. By introducing a carbazole skeleton into a compound having a quinazoline skeleton, the source of Low LUMO levels from the quinazoline skeleton. Therefore, when such a compound is used for the electron transport layer, the electron injection power to the light-emitting layer can be improved.

In addition, the carbazole skeleton and the quinazoline skeleton have the property of high charge transportability in the skeleton. Among the compounds that bond these backbones, the Highest Occupied Molecular Orbital (HOMO) and the LUMO extend intramolecularly. When the spread of the HOMO and LUMO in the molecule increases, the overlap with the orbital of the adjacent molecule also increases, and the charge transportability improves. Therefore, when the compound represented by the general formula (1) is used in any layer constituting the organic thin-film light-emitting element, electrons generated from the cathode or holes generated from the anode can be efficiently transported, and the organic thin-film can emit light. The drive voltage of the element decreases. As a result, the light-emitting efficiency of the organic thin-film light-emitting element can be improved.

Furthermore, by the expansion of the molecular orbital of the compound represented by the general formula (1), the radicals generated when receiving the charge become stable. In addition, originally the carbazole skeleton and the quinazoline skeleton have high stability with respect to electric charge, that is, electrochemical stability. Therefore, when the compound represented by the general formula (1) is used in any layer constituting the organic thin-film light-emitting element, the durability life of the organic thin-film light-emitting element is improved.

In addition, both the carbazole skeleton and the quinazoline skeleton have rigid structures in which a plurality of rings are condensed. Therefore, compounds having these skeletons exhibit high glass transition temperatures. In addition, when such a compound is sublimated, due to its rigid structure, the molecules are not entangled one by one, but are sublimated stably. In this way, the compound represented by the general formula (1) has a high glass transition temperature, so that the heat resistance of the organic thin-film light-emitting element is improved. In addition, it is possible to obtain a high-quality compound formed by stable sublimation of the compound represented by the general formula (1). Therefore, the durability life of the organic thin-film light-emitting element is improved.

These effects are not sufficient when one carbazole skeleton is substituted on the quinazoline skeleton. A sufficiently large effect can be obtained by substituting two carbazole skeletons on the quinazoline skeleton.

From the above, since the compound represented by the general formula (1) has two carbazole skeletons and a quinazoline skeleton in the molecule, high luminous efficiency, low driving voltage, and long durability can be achieved.

In particular, the compound represented by the general formula (1) is preferably used in a light-emitting layer or an electron transport layer of an organic thin-film light-emitting element due to its characteristics, and is particularly preferably used in an electron transport layer.

In the general formula (1), L ¹ is linked at any position among X ¹ to X ⁸ and R ⁵⁵ , and L ² is linked at any position among X ⁹ to X ¹⁶ and R ⁵⁶ .

Here, for example, that L ¹ is bonded at the position of X ¹ means that although X ¹ is CR ¹ , R ¹ itself does not exist, and L ¹ is directly bonded to a carbon atom. In addition, the fact that L ¹ is linked at the position of R ⁵⁵ means that R ⁵⁵ itself does not exist, but the nitrogen atom of the carbazole skeleton is directly linked to L ¹ .

The positions of L ¹ and L ² of the quinazoline skeleton are substitution positions on the six-membered ring of the electron-withdrawing nitrogen atom in the quinazoline skeleton. The low LUMO energy levels derived from the quinazoline skeleton are distributed on the six-membered ring of the electron-withdrawing nitrogen atom. Therefore, when the carbazole skeleton is bonded to this position, the effect of increasing the LUMO level of the compound is large. Thereby, as described above, the electron injection force can be improved.

In the general formula (1), it is preferable that L ¹ is connected at the position of X ³ . ^In addition, it is preferable that L2 is connected at the position of ^X14 . The reason for this is that the effect of raising the LUMO level of the compound becomes particularly large when these positions are connected.

However, in the general formula (1), the case where L ¹ is connected at the position of R ⁵⁵ and L ² is connected at the position of R ⁵⁶ is excluded. The reason for this is that when the quinazoline skeleton and the nitrogen atom of the carbazole skeleton are connected, the effect of raising the LUMO level of the compound is small. In the case where the quinazoline skeleton is linked by the nitrogen atom of only one of the two carbazole skeletons, the effect of increasing the LUMO level of the compound can be maintained. However, when the quinazoline skeleton is connected to the quinazoline skeleton through the nitrogen atom of either of the two carbazole skeletons, this effect cannot be maintained, and thus the electron injection force of the compound becomes small.

Either L ¹ or L ² must be a substituted or unsubstituted arylidene group, or a substituted or unsubstituted heteroarylidene group. This is because the molecules become more rigid, the glass transition temperature becomes higher, and the heat resistance of the organic thin-film light-emitting element improves.

L ¹ and L ² are single bonds, substituted or unsubstituted arylidene groups, or substituted or unsubstituted heteroarylidene groups. When L ¹ and L ² are substituted arylidene groups or substituted heteroarylidene groups, the substituents are as described above, preferably alkyl groups, cycloalkyl groups, heterocyclic groups, aryl ether groups, aryl groups A thioether group, an aryl group, a heteroaryl group, a halogen atom, a cyano group, or an amine group, more preferably a heterocyclic group, an aryl group, a heteroaryl group, a halogen atom, a cyano group, or an amine group, more preferably an aryl group , heteroaryl, or amine.

L ¹ and L ² are more preferably a single bond and an aryl group having 6 or more and 24 or less carbon atoms, and more preferably a single bond and a phenyl group. L ¹ and L ² are linking groups that form the periphery of the quinazoline skeleton that forms the LUMO level as the electron conduction level. Therefore, a single bond and an aryl group with little influence on the LUMO level of the quinazoline are preferable. In addition, a single bond and a phenyl group that are small in size and have high intermolecular electron transport properties are more preferable.

In the general formula (1), it is preferable that L ¹ is a single bond, and L ² is a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. In this case, L ² is preferably a substituted or unsubstituted arylidene group, and L ² is more preferably a substituted or unsubstituted phenylene group.

In addition, in the general formula (1), it is preferable that L ² is a single bond, and L ¹ is a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. In this case, L ¹ is preferably a substituted or unsubstituted arylidene group, and L ¹ is more preferably a substituted or unsubstituted phenylene group.

The reason is that if only any one of L ¹ or L ² is a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, it will be brought by the bond of the carbazole skeleton. The effect of increasing the LUMO level becomes greater.

In addition, X ⁿ (n=1 to 16) on the carbazole skeleton is CR ⁿ (n=1 to 16) or a nitrogen atom, respectively. R ⁿ (n=1~16) are independently selected from hydrogen atom, alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl ether group, arylthio group In the group consisting of ether group, halogen atom, cyano group, amine group, carbonyl group, carboxyl group, oxycarbonyl group, carboxyl group and -P(=O)R ¹⁷ R ¹⁸ .

Substituents other than hydrogen atoms are introduced to modify the electronic state of the carbazole skeleton. For example, an aromatic heterocyclic group containing an oxygen atom (hereinafter referred to as an "oxygen-containing aromatic heterocyclic group") or an aromatic heterocyclic group containing a sulfur atom (hereinafter referred to as a "sulfur-containing aromatic heterocyclic group") and the like are electron donors The electron-donating group enhances the electron-donating property of the carbazole skeleton. Other On the one hand, electron-withdrawing substituents such as cyano groups reduce the electron-donating properties of the carbazole skeleton.

Among these substituents, particularly preferred R ⁿ (n=1-16) is a hydrogen atom. The reason for this is that when R ⁿ (n=1~16) is a hydrogen atom, the volume around the quinazoline skeleton that forms the LUMO level, which is the electron conduction level, becomes smaller, and the electron transport property between molecules is further improved. .

R ⁵¹ to R ⁵⁴ are as described above, preferably a hydrogen atom, a cycloalkyl group, a heterocyclic group, an aryl ether group, an aryl sulfide group, an aryl group, a heteroaryl group, a halogen atom, a cyano group, and an amine A hydrogen atom, an aryl group, a heteroaryl group, a halogen atom, a cyano group, and an amine group are more preferred, and a hydrogen atom is particularly preferred. As described above, R ⁵⁵ and R ⁵⁶ are preferably aryl groups.

The LUMO level of the compound represented by the general formula (1) is slightly lower than the LUMO level of a material having an anthracene skeleton, which is commonly used as a host material for a blue light-emitting layer. Therefore, in the organic thin-film light-emitting element, it is preferable to use a compound having an anthracene skeleton for the light-emitting layer, among them for the blue light-emitting layer, and use the compound represented by the general formula (1) for the electron transport layer or the electron injection layer. . In such an organic thin-film light-emitting element, electron injection into the blue light-emitting layer can be appropriately suppressed. Along with this, the inside of the light-emitting layer can be suppressed from being in a state of excess electrons, and the carrier balance can be achieved. Thereby, the luminous efficiency and durability life of the organic thin-film light-emitting element are improved.

In addition, the compound represented by the general formula (1) easily accepts electrons from a compound having a pyrene skeleton, a phenanthroline skeleton, or a fluoranthene skeleton. These compounds can also transport electrons when the organic thin-film light-emitting device is driven at a low voltage. Therefore, it is preferable to use a compound having a pyrene skeleton or a compound having a phenanthroline skeleton in the layer in contact with the cathode side of the layer containing the compound represented by the general formula (1) in the organic thin-film light-emitting element. compounds, or compounds with a fluoranthene skeleton. Such an organic thin-film light-emitting element can be driven at a low voltage.

When the compound having a pyrene skeleton has a substituted or unsubstituted aryl group or heteroaryl group at the 1 and 6 positions, the electron transport property becomes large, which is more preferable.

The compound having a phenanthroline skeleton is more preferably a compound having a plurality of phenanthroline skeletons in the molecule in order to disperse charges and accelerate electron transfer.

In order to increase the deep LUMO energy of the fluoranthene skeleton, the compound having a fluoranthene skeleton is more preferably a compound having a fluoranthene skeleton and an amine group.

The compound represented by the general formula (1) is not particularly limited, but the following examples are specifically mentioned.

In the synthesis of the compound represented by the general formula (1), a known method can be used. The carbazole skeleton is commercially available in which a halogen atom or a boronic acid is bonded. As a synthesis method, for example, a method of coupling reaction of a substituted or unsubstituted carbazolyl boronic acid derivative and a substituted or unsubstituted halogenated quinazoline derivative with a palladium catalyst or a nickel catalyst is mentioned. , or using substituted or unsubstituted carbazole derivatives with substituted or unsubstituted carbazole derivatives Method for coupling reaction of substituted halogenated quinazoline derivatives, or method for coupling reaction using substituted or unsubstituted halogenated carbazole derivatives and substituted or unsubstituted quinazolinyl boronic acid derivatives, etc. , but not limited to these reactions.

Borate esters can also be used in place of boric acid. The halogen atom bonded to the carbazole skeleton can be converted into a boronate ester by a known method. The quinazoline skeleton can be synthesized from a substituted or unsubstituted 2-aminobenzonitrile derivative and a Grignard reagent through a cyclization reaction using a known method. Halogenated quinazolines are commercially available, so they can also be used.

Among the compounds represented by the general formula (1), the reactivity of L ¹ among L ¹ and L ² of the quinazoline skeleton is higher. Therefore, by appropriately selecting the catalyst or the reaction temperature, the bonding reaction of the carbazole to the quinazoline can be selectively carried out.

The compound represented by the general formula (1) is preferably used as an electronic element material in electronic elements such as organic thin-film light-emitting elements, photoelectric conversion elements, lithium ion batteries, fuel cells, and transistors. Among them, it is particularly preferable to use it as a light-emitting element material in an organic thin-film light-emitting element.

The photoelectric conversion element is an element having an anode and a cathode, and an organic layer interposed between the anode and the cathode. The organic layer has a photoelectric conversion layer that converts light energy into electrical signals. The compound represented by the general formula (1) has excellent electron transport properties, so it is preferably used for a photoelectric conversion layer, and more preferably an n-type material used for the photoelectric conversion layer.

The light-emitting element material refers to a material used in any layer of the organic thin-film light-emitting element. In addition to the materials used in the layers selected from the hole transport layer, the light emitting layer, and the electron transport layer as described later, the light-emitting element material also includes the protection of the electrode. The material used in the covering (cap). By using the compound represented by the general formula (1) in any layer of an organic thin-film light-emitting element, high luminous efficiency can be obtained, and an organic thin-film light-emitting element with low driving voltage and high durability can be obtained.

<Organic thin film light-emitting element>

Hereinafter, the organic thin-film light-emitting element according to an embodiment of the present invention will be described in detail. The organic thin-film light-emitting element according to the embodiment of the present invention has an anode, a cathode, and an organic layer interposed between the anode and the cathode, and the organic layer emits light by electric energy. Here, the organic layer preferably has at least a light-emitting layer and an electron transport layer.

Preferable constitutions of the organic layer include, in addition to the constitution of the light-emitting layer/electron transport layer, 1) hole transport layer/light-emitting layer/electron transport layer, 2) hole transport layer/light-emitting layer/electron transport layer /Electron injection layer, 3) Hole injection layer/hole transport layer/light emitting layer/electron transport layer/electron injection layer etc. In addition, each of the layers may be either a single layer or a multilayer. In addition, it may be a laminate type having a plurality of phosphorescent light-emitting layers or fluorescent light-emitting layers, or may be a structure in which a fluorescent light-emitting layer and a phosphorescent light-emitting layer are combined. Moreover, the structure which laminated|stacked the light-emitting layers each showing mutually different light emission colors may be sufficient.

In addition, the element structure may be a tandem type structure in which a plurality of layers are laminated with an intermediate layer interposed therebetween. At least one of the organic layers included in the multilayer structure is preferably a phosphorescent light-emitting layer. The intermediate layer is also commonly referred to as an intermediate electrode, an intermediate conducting layer, a charge generating layer, an electron withdrawing layer, a connecting layer or an intermediate insulating layer. Specific examples of the laminated structure include: 1) hole transport layer/light emitting layer/electron transport layer/charge generation layer/hole transport layer/light emitting layer/electron transport layer, 2) hole injection layer/hole pass Transport layer/light emitting layer/electron transport layer/electron injection layer/charge generation layer/hole injection layer/hole transport layer/light emitting layer/electron transport layer/electron injection layer, etc. A charge generation layer is included between the anode and the cathode as a The laminated structure of the intermediate layer. As the material constituting the intermediate layer, pyridine derivatives, phenanthroline derivatives and the like can be preferably used. When the material constituting the intermediate layer is a phenanthroline derivative, the phenanthroline derivative is more preferably a compound having two or more phenanthroline skeletons in the molecule.

The organic thin-film light-emitting element of the present invention (hereinafter, sometimes referred to as a light-emitting element) contains the compound represented by the general formula (1) in the organic layer. The compound represented by the general formula (1) can be used in any layer in the device structure, and is preferably used for the light-emitting layer of a light-emitting device because of its high electron injection and transport capability, fluorescence quantum yield and film stability , electron transport layer or intermediate layer. In particular, the compound represented by the general formula (1) is more preferably used for the electron transport layer or the intermediate layer, and particularly preferably used for the electron transport layer, from the viewpoint of excellent electron injection and transport ability.

(substrate)

In order to maintain the mechanical strength of the light-emitting element, the light-emitting element is preferably formed on the substrate. As the substrate, a glass substrate such as soda glass or alkali-free glass can be preferably used. The thickness of the glass substrate should just be a thickness sufficient to maintain mechanical strength, and it is sufficient if it is 0.5 mm or more. The material of the glass is preferably alkali-free glass because there are few ions eluted from the glass. Alternatively, soda lime glass to which a barrier coat of SiO ₂ or the like was applied is also commercially available and can also be used. In addition, as long as the first electrodes formed on the substrate function stably, the substrate does not need to be glass, for example, it may be a plastic substrate.

(Anode and Cathode)

In the organic thin-film light-emitting element according to the embodiment of the present invention, the anode and the cathode have a function of supplying a sufficient current to cause the element to emit light. In order to capture light, at least one of the anode and the cathode is preferably transparent or translucent. Usually, the anode formed on the substrate is a transparent electrode.

The material used for the anode is a material that can efficiently inject holes into the organic layer, and is not particularly limited as long as it is a transparent or translucent material that captures light. Examples of materials include conductive metal oxides such as tin oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO), metals such as gold, silver, and chromium, and iodine. Inorganic conductive substances such as copper sulfide and copper sulfide, conductive polymers such as polythiophene, polypyrrole, and polyaniline, etc. These electrode materials may be used alone, or a plurality of materials may be laminated or mixed for use.

The substrate on which the anode is formed is particularly preferably ITO glass in which an ITO film is formed on the surface of glass, or NESA glass in which a film containing tin oxide as a main component is formed on the surface of glass. In the case of ITO glass, the method for forming an ITO film is not particularly limited as long as it is a method capable of forming an ITO film, such as an electron beam beam method, a sputtering method, and a chemical reaction method.

The material used for the cathode is not particularly limited as long as it can efficiently inject electrons into the light-emitting layer. The materials are usually preferably metals such as platinum, gold, silver, copper, iron, tin, aluminum, indium, etc., alloys or multilayer laminates of these metals and metals with low work function such as lithium, sodium, potassium, calcium, and magnesium. Among them, the main component of the material used for the cathode is the reduction of the resistance value, the ease of film formation, the stability of the film, the luminous efficiency, and the like. Preferably it is aluminum, silver or magnesium. In particular, when the cathode is made of magnesium and silver, the electron injection into the electron transport layer and the electron injection layer becomes easy, and the light-emitting element can be driven at a lower voltage, which is preferable. The manufacturing method of these electrodes is not specifically limited, For example, resistance heating, electron beam beam, sputtering, ion plating, coating, etc. are mentioned.

(protective film layer)

In order to protect the cathode, it is preferable to laminate a protective film layer (cap layer) on the cathode. The material constituting the protective film layer is not particularly limited, and examples thereof include metals such as platinum, gold, silver, copper, iron, tin, aluminum, and indium, alloys using these metals, silicon dioxide, titanium oxide, and silicon nitride. Inorganic substances such as polyvinyl alcohol, polyvinyl chloride, and organic polymer compounds such as hydrocarbon-based polymer compounds. Moreover, the compound represented by General formula (1) can also be used as this protective film layer. Wherein, when the light-emitting element is an element structure that extracts light from the cathode side (top emission structure), the material used for the protective film layer is selected from materials having light transmittance in the visible light range.

(hole transport layer)

The hole transport layer is formed by a method of laminating or mixing one or more kinds of hole transport materials, or a method of using a mixture of a hole transport material and a polymer binder. In addition, the hole transport material is required to efficiently transport holes injected from the anode between electrodes to which an electric field is applied. Therefore, the hole transport material is preferably a material that has high hole injection efficiency and can efficiently transport the injected holes. Therefore, a material having a suitable free potential, high hole mobility, and excellent stability is preferable, and impurities that become traps are not easily generated during manufacture and use of such a material.

Substances satisfying such conditions are not particularly limited, for example, preferably: 4,4'-bis(N-(3-methylphenyl)-N-phenylamino)biphenyl (TPD), 4,4'-bis(N-(1-naphthyl)-N-benzene amino)biphenyl (NPD), 4,4'-bis(N,N-bis(4-biphenyl)amino)biphenyl (TBDB), bis(N,N'-diphenyl-4 -Aminophenyl)-N,N-diphenyl-4,4'-diamino-1,1'-biphenyl (TPD232) and other benzidine derivatives; 4,4',4"-tris( 3-Methylphenyl(phenyl)amino)triphenylamine (m-MTDATA), 4,4',4"-tris(1-naphthyl(phenyl)amino)triphenylamine (1 -TNATA) and the like group of materials known as starburst-like arylamines; materials with a carbazole skeleton, wherein carbazole polymers, specifically bis(N-arylcarbazole) or bis(N-alkyl) Derivatives of carbazole dimers such as carbazole), derivatives of carbazole trimers, derivatives of carbazole tetramers; bitriphenylene compounds, stilbene compounds, hydrazone compounds; pyrazoline Derivatives, benzofuran derivatives, thiophene derivatives, oxadiazole derivatives, phthalocyanine derivatives, porphyrin derivatives and other heterocyclic compounds; fullerene derivatives; with a side chain selected from the group of compounds Polycarbonate or styrene derivatives, polythiophene, polyaniline, polyphenylene, polyvinyl carbazole and polysilane, etc.

In addition, inorganic compounds such as p-type Si and p-type SiC can also be used as the hole transport material.

In addition, the compound represented by the general formula (1) can also be used as a hole transport material because of its excellent electrochemical stability.

(hole injection layer)

A hole injection layer may also be provided between the anode and the hole transport layer. By providing the hole injection layer, the light-emitting element is driven at a lower voltage, and the durability life is also improved. Materials with lower free potentials than those typically used in hole transport layers may preferably be used in the hole injection layer. Specifically, the above-mentioned benzidine derivatives such as TPD232, starburst-like arylamine materials, or phthalocyanine derivatives, etc. can be mentioned.

In addition, the hole injection layer is also preferably constituted by the acceptor compound alone, or by doping the acceptor compound into another hole injection material. Examples of acceptor compounds include iron (III) chloride, aluminum chloride, gallium chloride, indium chloride, metal chlorides such as antimony chloride, molybdenum oxide, vanadium oxide, tungsten oxide, and ruthenium oxide. Common metal oxides, tris (4-bromophenyl) ammonium hexachloroantimonate (Tris (4-bromophenyl) Aminium hexachloroantimonate, TBPAH)-like charge transfer complexes. Moreover, the organic compound which has a nitro group, a cyano group, a halogen atom, or a trifluoromethyl group in a molecule|numerator, a quinone type compound, an acid anhydride type compound, a fullerene, etc. can also be mentioned.

Specific examples of these compounds include hexacyanobutadiene, hexacyanobenzene, tetracyanoethylene, tetracyanoquinodimethane (TCNQ), tetrafluorotetracyanoquinodimethane ( Tetrafluorotetracyano quinodimethane, F ₄ -TCNQ), 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazabitriphenylene (2,3,6 ,7,10,11-hexacyano-1,4,5,8,9,12-hexaaza triphenylene, HAT-CN ₆ ), p-fluoranil, p-chloranil ), tetrabromo-p-benzoquinone (p-bromanil), p-benzoquinone, 2,6-dichlorobenzoquinone, 2,5-dichlorobenzoquinone, tetramethylbenzoquinone, 1,2,4,5-tetra Cyanobenzene, o-dicyanobenzene, p-dicyanobenzene, 1,4-dicyano-2,3,5,6-tetrafluorobenzene, 2,3-dichloro-5,6-dicyano Benzoquinone, o-dinitrobenzene, m-dinitrobenzene, p-dinitrobenzene, o-cyanonitrobenzene, m-cyanonitrobenzene, p-cyanonitrobenzene, 1,4-naphthoquinone, 2 ,3-Dichloro-1,4-naphthoquinone, 1-nitronaphthalene, 2-nitronaphthalene, 1,3-dinitronaphthalene, 1,5-dinitronaphthalene, 9-cyanoanthracene, 9 -Nitroanthracene, 9,10-Anthraquinone, 1,3,6,8-Tetranitrocarbazole, 2,4,7-Trinitro-9-Pylenone, 2,3,5,6-Tetra Cyanopyridine, maleic anhydride, phthalic anhydride, C ₆₀ , and C ₇₀ , etc.

In either the case where the hole injection layer is composed of the acceptor compound alone or the case where the hole injection material is doped with the acceptor compound, the hole injection layer may be one layer or a plurality of layers may be laminated. In addition, the hole injection material used in combination when doping the acceptor compound is more preferably the same as the compound used for the hole transport layer from the viewpoint of alleviating the hole injection barrier to the hole transport layer. compound of.

(Light Emitting Layer)

The light-emitting layer can be either a single layer or a multi-layer, and is formed of a light-emitting material (host material, dopant material), respectively. The light-emitting layer may be a mixture of host material and dopant material, or may be a single host material. That is, in the organic thin-film light-emitting element according to the embodiment of the present invention, in each light-emitting layer, only the host material or the dopant material may emit light, or both the host material and the dopant material may be allowed to emit light. The light-emitting layer preferably contains a mixture of a host material and a dopant material from the viewpoint of efficiently utilizing electric energy and obtaining light emission with high color purity.

In addition, the host material and the dopant material may be one type, respectively, or a combination of multiple types. The dopant material can be included in the whole of the host material, or partially included in the in the main material. The dopant material can be layered or dispersed. The emission color of the light-emitting element can be controlled according to the type of dopant material. If the amount of the dopant material is too large, a concentration extinction phenomenon will occur, so it is preferably used in an amount of 20% by weight or less, more preferably 10% by weight or less, with respect to the host material. The doping method can be co-evaporated with the host material or preliminarily mixed with the host material and then vapor-deposited at the same time.

The light-emitting material is not particularly limited, and specifically, condensed ring derivatives such as anthracene and pyrene, which are conventionally known as light-emitting bodies, and metal chelated 8- Oxinoid compounds; bis-styryl derivatives such as bis-styryl anthracene derivatives or stilbene benzene derivatives; tetraphenylbutadiene derivatives, indene derivatives, coumarin derivatives , oxadiazole derivatives, pyrrolopyridine derivatives, perone derivatives, cyclopentadiene derivatives, oxadiazole derivatives, thiadiazolopyridine derivatives, dibenzofuran derivatives, carbazole derivatives compounds, indolocarbazole derivatives; polyphenylene vinylene derivatives, polyparaphenylene derivatives, polythiophene derivatives and other polymers.

(chrysene)、稠四苯、聯三伸苯、苝、熒蒽、茀、茚等具有縮合芳基環的化合物或其衍生物；N,N'-二萘基-N,N'-二苯基-4,4'-二苯基-1,1'-二胺等芳香族胺衍生物；以三(8-羥基喹啉)鋁(III)為代表的金屬螯合化8-羥基喹啉酮化合物；二苯乙烯基苯衍生物等雙苯乙烯基衍生物；四苯基丁二烯衍生物、茚衍生物、香豆素衍生物、噁二唑衍生物、吡咯并吡啶衍生物、紫環酮衍生物、環戊二烯衍生物、吡咯并吡咯衍生物、噻二唑并吡啶衍生物、二苯并呋喃衍 生物、咔唑衍生物、吲哚并咔唑衍生物、三嗪衍生物；聚苯乙炔衍生物、聚對苯衍生物、聚茀衍生物、聚乙烯基咔唑衍生物、聚噻吩衍生物等。 The host material is not particularly limited, and can be used: naphthalene, anthracene, phenanthrene, pyrene,

(chrysene), condensed tetraphenyl, bi-triphenylene, perylene, fluoranthene, perylene, indene and other compounds with condensed aryl rings or their derivatives; N,N'-dinaphthyl-N,N'-diphenyl Aromatic amine derivatives such as yl-4,4'-diphenyl-1,1'-diamine; metal chelated 8-hydroxyquinoline represented by tris(8-hydroxyquinoline)aluminum(III) Ketone compounds; distyryl derivatives such as distyrylbenzene derivatives; tetraphenylbutadiene derivatives, indene derivatives, coumarin derivatives, oxadiazole derivatives, pyrrolopyridine derivatives, violet Cyclic ketone derivatives, cyclopentadiene derivatives, pyrrolopyrrole derivatives, thiadiazolopyridine derivatives, dibenzofuran derivatives, carbazole derivatives, indolocarbazole derivatives, triazine derivatives ; Polyphenylene vinylene derivatives, polyparaphenylene derivatives, polyphenylene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

From the viewpoint that the LUMO level is close to the compound represented by the general formula (1), and the injection of electrons easily occurs, the host material when the compound represented by the general formula (1) is used as an electron transport material more preferably has an anthracene skeleton. compound of.

In addition, as the doping material in this case, compounds having a condensed aryl ring, such as naphthalene, anthracene, phenanthrene, pyrene, pyrene, triphenylene, perylene, fluoranthene, perylene, and indene, or their derivatives (for example, 2 -(Benzothiazol-2-yl)-9,10-diphenylanthracene or 5,6,11,12-tetraphenyl fused tetraphenyl, etc.); furan, pyrrole, thiophene, siloxane, 9-silicon (9-silafluorene), 9,9'-spirodisilazine, benzothiophene, benzofuran, indole, dibenzothiophene, dibenzofuran, imidazopyridine, phenanthroline, pyridine, pyrazine, naphthalene pyridine, quinoxaline, pyrrolopyridine, thioxanthene and other compounds with heteroaryl rings or their derivatives; borane derivatives, distyrylbenzene derivatives; 4,4'-bis(2-(4- Diphenylaminophenyl)vinyl)biphenyl, 4,4'-bis(N-(stilbene-4-yl)-N-phenylamino)stilbene and other aminostyryl derivatives Compounds; Aromatic acetylene derivatives, tetraphenylbutadiene derivatives, stilbene derivatives, aldazine derivatives, pyrrolomethylene derivatives, diketopyrrolo[3,4-c ] pyrrole derivatives; coumarins such as 2,3,5,6-1H,4H-tetrahydro-9-(2'-benzothiazolyl)quinizino[9,9a,1-gh]coumarin Derivatives; imidazole, thiazole, thiadiazole, carbazole, oxazole, oxadiazole, triazole and other azole derivatives and their metal complexes; and N,N'-diphenyl-N,N'-diphenyl Aromatic amine derivatives represented by (3-methylphenyl)-4,4'-diphenyl-1,1'-diamine, etc., are not particularly limited.

In addition, a phosphorescent light-emitting material may also be included in the light-emitting layer. A phosphorescent light-emitting material is a material that exhibits phosphorescent light emission even at room temperature. The phosphorescent light-emitting material is not particularly limited, but preferably contains a material selected from iridium (Ir), ruthenium (Ru), rhodium (Rh), palladium (Pd), platinum (Pt), osmium (Os), and rhenium (Re) An organometallic complex compound of at least one metal in the group consisting of. Among them, an organometallic complex having iridium or platinum is more preferable from the viewpoint of having a high phosphorescence emission yield even at room temperature.

As a host material used in combination with a phosphorescent dopant material, for example, indole derivatives, carbazole derivatives, indolocarbazole derivatives; nitrogen-containing aromatics having a pyridine, pyrimidine or triazine skeleton can be mentioned. Derivatives of compounds; derivatives of aromatic hydrocarbon compounds such as polyarylbenzene derivatives, spiro-indene derivatives, truxene derivatives, bis-triphenylene derivatives; dibenzofuran derivatives, dibenzothiophene Derivatives and other chalcogen-containing compounds; organometallic complexes such as quinoline beryllium complexes, etc. Among them, the host material is not limited to these compounds as long as the triplet energy is larger than the dopant material used, and electrons and holes are smoothly injected and transported from each transport layer.

The light-emitting layer may contain two or more phosphorescent dopant materials, and may contain two or more host materials. Furthermore, one or more kinds of light-emitting dopant and one or more kinds of fluorescent light-emitting dopant may be contained. When a phosphorescent light-emitting material is used in the light-emitting layer, the compound represented by the general formula (1) can be preferably used as an electron transport material.

The compound represented by the general formula (1) has high light-emitting properties, so it can also be used as a light-emitting material. The compound represented by the general formula (1) is in the blue to green range (400 It exhibits strong luminescence in the range of nm~600nm), so it can be preferably used as blue and green light-emitting materials. The compound represented by the general formula (1) has a high fluorescence quantum yield, so it can be preferably used as a fluorescent doping material. In addition, the carbazole skeleton and the quinazoline skeleton have a high triplet excitation energy level, and the compound represented by the general formula (1) can also be preferably used as a phosphorescent host material. In particular, it can be preferably used for a green phosphorescent host material and a red phosphorescent host material.

The preferable phosphorescent host or dopant is not particularly limited, and the following examples are specifically mentioned.

In addition, a thermally activated delayed fluorescent material may also be included in the light-emitting layer. Thermally activated delayed fluorescent materials are also commonly referred to as TADF (Thermally Activated Delayed Fluorescence) materials. Thermally activated delayed fluorescent materials promote the reverse intersystem crossing from the triplet excited state to the singlet excited state by reducing the energy gap between the energy level of the singlet excited state and the energy level of the triplet excited state. Materials with the generation probability of heavy state excitons. The thermally activated delayed fluorescent material may be a material that exhibits thermally activated delayed fluorescence by a single material, or a material that exhibits thermally activated delayed fluorescence by a plurality of materials. In the case where the material contains a variety of materials, it can be used in the form of a mixture, It can also be used by stacking layers containing each material. As the thermally activated delayed fluorescent material, known materials can be used. Specifically, for example, benzonitrile derivatives, triazine derivatives, diarylene derivatives, carbazole derivatives, indolocarbazole derivatives, hydrophenazine derivatives, thiazole derivatives, oxadi azole derivatives, etc., but not limited to these compounds.

(electron transport layer)

The electron transport layer is a layer located between the cathode and the light-emitting layer. The electron transport layer may be a single layer or a multi-layer, and may or may not be in contact with the cathode or the light-emitting layer. It is preferable that the electron transport layer includes two or more layers, and the compound represented by the general formula (1) is contained in the layers on the side in contact with the light-emitting layer. In addition, as described above, the compound represented by the general formula (1) easily accepts electrons from a compound having a pyrene skeleton, a phenanthroline skeleton, or a fluoranthene skeleton. Therefore, in the electron transport layer, the layer in contact with the cathode side preferably contains A compound having a phenanthroline skeleton, a pyrene skeleton, or a fluoranthene skeleton.

For the electron transport layer, it is desired that the electron injection efficiency from the cathode is high, the injected electrons are efficiently transported, and the electron injection efficiency into the light-emitting layer is high. Therefore, the material constituting the electron transport layer is preferably a material with high electron affinity, high electron mobility, and excellent stability. In addition, it is preferable that impurities that become traps are not easily generated during production and use of such a material.

On the other hand, it is also preferable that when the holes flowing out from the anode do not flow to the electron transport layer when the light-emitting layer recombines with electrons, the electron transport layer can effectively prevent the holes from flowing to the cathode side. In this case, even if the electron transport layer is composed of a material with a low electron transport capability, the effect of improving the luminous efficiency of the light-emitting element is the same as when the electron transport layer is composed of a material with a high electron transport capability. Therefore, this The electron transport layer of the invention also includes a hole blocking layer which can effectively prevent the migration of holes as the same meaning.

The electron transport material used in the electron transport layer is not particularly limited, and examples thereof include condensed polycyclic aromatic hydrocarbon derivatives such as naphthalene and anthracene, and compounds represented by 4,4'-bis(diphenylvinyl)biphenyl. Styryl-based aromatic ring derivatives, quinone derivatives such as anthraquinone or diphenoquinone, phosphorus oxide derivatives, hydroxyquinoline complexes such as tris(8-hydroxyquinoline)aluminum(III), benzohydroxyl Various metal complexes such as quinoline complexes, hydroxyazole complexes, azomethine complexes, tropolone metal complexes, and flavonol metal complexes. In terms of reducing the driving voltage of the light-emitting element and obtaining high luminous efficiency, the electron transport material is preferably a heteroaryl containing an element selected from carbon, hydrogen, nitrogen, oxygen, silicon, and phosphorus and having electron-accepting nitrogen. compounds with ring structures.

Examples of the aromatic heterocyclic ring containing electron accepting nitrogen include a pyridine ring, a pyrazine ring, a pyrimidine ring, a quinoline ring, a quinoxaline ring, a naphthyridine ring, a pyrimidopyrimidine ring, a benzoquinoline ring, phenanthroline ring, imidazole ring, oxazole ring, oxadiazole ring, triazole ring, thiazole ring, thiadiazole ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, phenanthroimidazole ring, etc.

The electron transporting material may be used alone, two or more kinds of the electron transporting material may be mixed and used, or one or more other electron transporting materials may be mixed and used in the electron transporting material.

The preferable electron transport material is not particularly limited, and the following examples are specifically mentioned.

[Chemical 16]

In addition to these compounds, International Publication No. 2004/63159, International Publication No. 2003/60956, "Applied Physics Letters" ((US), 1999, Vol. 74, No. 6, p. .865-867), "Organic Electronics" ((Netherlands), 2003, Vol. 4, No. 2-3, p. 113-121), International Publication No. 2010/113743, International Publication No. 2010/1817 The electron transport material disclosed in et al.

In addition, the compound represented by the general formula (1) also has high electron injection transport ability, so it can be used as an electron transport material. In the case of using the compound represented by the general formula (1), it is not necessary to limit it to only one kind, and a plurality of compounds represented by the general formula (1) may be mixed and used, and one or more other electrons of the general formula (1) may be used. The transport material is used in combination with the compound represented by the general formula (1).

In addition to the electron transport material, the electron transport layer may contain a donor material. Here, the donor material refers to a compound that improves the electron injection barrier, facilitates electron injection from the cathode or the electron injection layer to the electron transport layer, and further improves the conductivity of the electron transport layer.

Preferred examples of the donor material of the present invention include alkali metals, inorganic salts containing alkali metals, complexes of alkali metals and organic substances, alkaline earth metals, inorganic salts containing alkaline earth metals, or complexes of alkaline earth metals and organic substances things etc. Preferable types of alkali metals and alkaline earth metals include alkali metals such as lithium, sodium, and cesium, and alkaline earth metals such as magnesium and calcium, which have a low work function and have a large effect of improving electron transport capability.

In addition, since vapor deposition in a vacuum is easy and the handling is excellent, an inorganic salt or a complex of a metal and an organic substance is preferable rather than a single metal. Furthermore, the complex of a metal and an organic substance is more preferable from the point of easy handling in the air or the point of easy control of the addition concentration. Examples of inorganic salts include oxides such as LiO and Li ₂ O, nitrides, fluorides such as LiF, NaF, and KF, Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Rb ₂ CO ₃ , Carbonates such as Cs ₂ CO ₃ etc. In addition, in terms of cheap raw materials and easy synthesis, lithium is a preferable example of an alkali metal or an alkaline earth metal. Moreover, as a preferable example of the organic substance in the complex compound of a metal and an organic substance, quinoline, benzoquinoline, flavonol, hydroxyimidazopyridine, hydroxybenzoxazole, hydroxytriazole, etc. are mentioned. Among them, a complex of an alkali metal and an organic substance is preferable, a complex of lithium and an organic substance is more preferable, and lithium quinolate is particularly preferable. These donor materials can also be used by mixing two or more types.

The preferred doping concentration also depends on the material or the film thickness of the doped region. For example, when the donor material is an inorganic material such as alkali metal and alkaline earth metal, it is preferred to use an electron transport material and a donor material. An electron transport layer was prepared by co-evaporation so that the vapor deposition rate ratio was in the range of electron transport material: donor material = 10000: 1 to 2: 1. The vapor deposition rate ratio is more preferably 100:1 to 5:1, and more preferably 100:1 to 10:1. In addition, when the donor material is a complex of a metal and an organic substance, it is preferable that the ratio of the vapor deposition rate of the electron transport material to the donor material is the electron transport material: the donor material=100:1~ Co-evaporation was performed so as to be in the range of 1:100 to form an electron transport layer. The vapor deposition rate ratio is more preferably 10:1 to 1:10, and more preferably 7:3 to 3:7.

In addition, the electron transport layer in which the compound represented by the general formula (1) is doped with a donor material can also be used as a charge generation layer in a multilayer light-emitting element in which a plurality of light-emitting elements are connected. Especially when doped with an alkali metal or an alkaline earth metal as a donor material, the layer can preferably be used as a charge generating layer.

(electron injection layer)

An electron injection layer may also be provided between the cathode and the electron transport layer. Typically the electron injection layer is inserted for the purpose of facilitating the injection of electrons from the cathode into the electron transport layer. A compound having a heteroaryl ring structure containing electron-accepting nitrogen may be used for the electron injection layer, or a layer containing the donor material may be used. Formation represented by the general formula (1) Compounds may also be included in the electron injection layer. In addition, an inorganic substance of an insulator or a semiconductor may also be used for the electron injection layer. By using these materials, the short circuit of the light-emitting element can be effectively prevented, and the electron injection property can be improved, which is preferable.

Such an insulator preferably uses at least one metal compound selected from the group consisting of alkali metal chalcogenides, alkaline earth metal chalcogenides, alkali metal halides, and alkaline earth metal halides.

It is more preferable to use a complex of an organic substance and a metal as a donor material for the electron injection layer, since it is easy to adjust the film thickness. As a preferable example of the organic substance in such a complex, hydroxyquinoline, benzohydroxyquinoline, pyridylphenol, flavonol, hydroxyimidazopyridine, hydroxybenzoxazole, hydroxytriazole, etc. are mentioned. Among them, a complex of an alkali metal and an organic substance is preferable, a complex of lithium and an organic substance is more preferable, and lithium quinolate is particularly preferable.

The method of forming each of the layers constituting the light-emitting element is not particularly limited to resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular lamination, coating method, and the like, and is generally preferable in terms of element characteristics. Resistance heating evaporation or electron beam evaporation.

The thickness of the organic layer also depends on the resistance value of the light-emitting material, so it cannot be limited, and is preferably 1 nm to 1000 nm. The film thicknesses of the light-emitting layer, the electron transport layer, and the hole transport layer are respectively preferably 1 nm or more and 200 nm or less, and more preferably 5 nm or more and 100 nm or less.

The organic thin-film light-emitting element according to the embodiment of the present invention has a function of converting electrical energy into light. Here, the electrical energy mainly uses DC current, and pulse wave can also be used current or alternating current. The current value and the voltage value are not particularly limited, but are preferably selected so as to obtain the maximum brightness with the lowest possible energy in consideration of the power consumption and the life of the element.

The organic thin-film light-emitting element according to the embodiment of the present invention can be preferably used as a display device such as a display that displays in a matrix and/or segment, for example.

The matrix method is a method in which the pixels for display are arranged two-dimensionally in a lattice or mosaic shape, and characters or images are displayed as a set of pixels. The shape or size of the pixel is determined according to the usage. For example, when displaying images and characters on personal computers, monitors, and TVs, quadrilateral pixels with one side of 300 μm or less are usually used, and in the case of large-scale displays such as display panels, one side of which is on the order of millimeters (mm) is used. pixel. In the case of monochromatic display, pixels of the same color may be arranged, and in the case of color display, pixels of red, green, and blue are arranged and displayed. In this case, there are typically a delta type and a stripe type. Moreover, the driving method of the matrix may be either a line-sequential driving method or an active matrix. The structure of the line-sequential driving is simple, but considering the operational characteristics, an active matrix is sometimes better, so it is preferable to use this driving method according to the application.

The segment method is a method in which a pattern is formed so as to display predetermined information, and an area determined by the arrangement of the pattern is made to emit light. Examples of displays using a segmented method include time and temperature displays of digital timepieces and thermometers, operating status displays of audio equipment, induction cookers, and the like, and panel displays of automobiles. matrix method The segmented method can also coexist on the same panel.

The organic thin-film light-emitting element of the embodiment of the present invention can also be suitably used as a backlight for various devices and the like. Backlights are mainly used for the purpose of improving the visibility of display devices that do not emit light by themselves, and can be used in liquid crystal display devices, timepieces, audio devices, automotive panels, display panels, labels, and the like. In particular, the organic thin-film light-emitting element of the present invention can be preferably used for a backlight of a liquid crystal display device and a personal computer for which thinning is being studied, and can provide a thinner and lighter backlight than before.

The organic thin-film light-emitting element of the embodiment of the present invention can also be suitably used as a lighting device such as organic EL lighting. Organic EL lighting can be used for general lighting, display lighting, tail lamps of automobiles, and the like, and the organic thin-film light-emitting element of the present invention can be preferably used for these.

[Example]

Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited to these Examples at all.

Synthesis Example 1

Synthesis of Intermediate [A]

Put 2,4-dichloroquinazoline 9.90g (50.0g in a 500mL three-necked flask) mmol), 15.1 g (52.5 mmol) of 9-phenylcarbazole-3-boronic acid, 250 mL of 1,2-dimethoxyethane, and 38 mL (75 mmol) of a 2M aqueous sodium carbonate solution, and the inside of the container was replaced with nitrogen. To this mixture was added 0.351 g (0.500 mmol) of bis(triphenylphosphine)palladium(II) chloride, and the mixture was heated and refluxed in an oil bath at 90°C for 5 hours. After completion of the reaction, the mixture was cooled to room temperature, 200 mL of water was added to the contents of the flask, and the precipitated solid was collected by filtration to obtain 19.2 g of intermediate [A]. The obtained solid was dissolved in toluene and purified by silica gel column chromatography using a heptane-toluene mixed developing solvent.

Synthesis of Compound [1]

Into a 100mL three-necked flask, put 2.03g (5.00mmol) of intermediate [A], 1.51g (5.25mmol) of 4-(9H-carbazol-9-yl)phenylboronic acid, 50mL of 1,4-dioxane, 3.8 mL (7.5 mmol) of 2M tripotassium phosphate aqueous solution was used to replace the inside of the vessel with nitrogen. To this mixture were added 0.046 g (0.050 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 0.028 g (0.10 mmol) of tricyclohexylphosphine, and the mixture was heated under reflux in an oil bath at 110°C for 4 hours. After completion of the reaction, it was cooled to room temperature, 50 mL of water was added to the contents of the flask, and the precipitated solid was collected by filtration to obtain 2.82 g of compound [1]. The obtained solid was dissolved in toluene and purified by silica gel column chromatography. Further, will The purified product was dissolved by heating in 40 mL of butyl acetate, cooled, recrystallized, collected by filtration, and then vacuum-dried to obtain 2.36 g of compound [1] as a yellow-white solid.

The obtained yellow-white solid was confirmed to be compound [1] by mass spectrometry (JMS-Q1000TD manufactured by JEOL Ltd.).

Compound [1] was used as a light-emitting element material after being purified by sublimation at about 330° C. under a pressure of 1×10 ⁻³ Pa using an oil diffusion pump.

Synthesis Example 2

Synthesis of Intermediate [B]

In a 500mL three-necked flask, put 5.94g (30.0mmol) of 2,4-dichloroquinazoline, 5.15g (33.0mmol) of 4-chlorophenylboronic acid, 150mL of 1,2-dimethoxyethane, 2M sodium carbonate An aqueous solution of 23 mL (45 mmol) was used to replace the inside of the vessel with nitrogen. To this mixture was added 0.211 g (0.300 mmol) of bis(triphenylphosphine)palladium(II) chloride, and the mixture was heated and refluxed in an oil bath at 90°C for 5 hours. After completion of the reaction, it was cooled to room temperature, 200 mL of water was added to the contents of the flask, and the precipitated solid was collected by filtration to obtain 8.12 g of intermediate [B]. The obtained solid was dissolved in toluene and purified by silica gel column chromatography using a heptane-toluene mixed developing solvent.

Synthesis of Intermediate [C]

4.11 g (15.0 mmol) of intermediate [B], 4.73 g (16.5 mmol) of 9-phenylcarbazole-3-boronic acid, 150 mL of 1,2-dimethoxyethane, and 2M phosphoric acid were placed in a 300 mL three-necked flask. 11 mL (22.5 mmol) of tripotassium aqueous solution was purged with nitrogen in the container. To this mixed solution was added 0.105 g (0.150 mmol) of bis(triphenylphosphine)palladium(II) chloride, and the mixture was heated and refluxed in an oil bath at 90°C for 7 hours. After completion of the reaction, it was cooled to room temperature, 100 mL of water was added to the contents of the flask, and the precipitated solid was collected by filtration to obtain 5.95 g of intermediate [C]. The obtained solid was dissolved in toluene and purified by silica gel column chromatography using a heptane-toluene mixed developing solvent.

Synthesis of Compound [2]

Into a 100 mL three-necked flask, put 2.40 g (5.00 mmol) of intermediate [C], 0.918 g (7.50 mmol) of carbazole, and 0.721 g (7.50 g of sodium tertiary butoxide) mmol), 50 mL of o-xylene was added, and the inside of the container was replaced with nitrogen. To this mixed liquid were added 0.046 g (0.050 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 0.028 g (0.10 mmol) of tricyclohexylphosphine, and the mixture was heated under reflux in an oil bath at 150°C for 3 hours. After completion of the reaction, it was cooled to room temperature, 30 mL of methanol was added to the contents of the flask, and the precipitated solid was collected by filtration to obtain 2.88 g of compound [2]. The obtained solid was dissolved in toluene and purified by silica gel column chromatography. Furthermore, the purified product was dissolved by heating in 40 mL of butyl acetate, cooled, recrystallized, collected by filtration, and then vacuum-dried to obtain 2.39 g of compound [2] as a yellow-white solid.

The obtained yellow-white solid was confirmed to be compound [2] by mass spectrometry (JMS-Q1000TD manufactured by JEOL Ltd.).

Compound [2] was used as a light-emitting element material after being purified by sublimation at 330° C. under a pressure of 1×10 ⁻³ Pa using an oil diffusion pump.

Synthesis Example 3

Synthesis of Intermediate [E]

The synthesis of the intermediate E was carried out by applying the method described in International Publication No. 2006/049013. That is, put magnesium 2.43 in a 500mL three-necked flask g, and 10 mL of dry tetrahydrofuran was added to replace the inside of the container with nitrogen. Into the flask, 200 mL of a dry tetrahydrofuran solution of 32.2 g (100 mmol) of 9-(4-bromophenyl)carbazole was added dropwise to prepare a Grignard reagent. Thereto, 50 mL of a dry tetrahydrofuran solution of 7.63 g (50 mmol) of 2-amino-5-chlorobenzonitrile was added dropwise over 30 minutes. Further, after refluxing for 1.5 hours, it was cooled to 0°C with an ice-water bath. Then, 100 mL of a dry tetrahydrofuran solution of 13.2 g (60 mmol) of 4-bromobenzyl chloride was added dropwise over 10 minutes, and the mixture was heated and refluxed in an oil bath at 60°C for 2 hours. After completion of the reaction, the mixture was cooled to 0° C. with an ice-water bath, and a saturated aqueous ammonium chloride solution was added. The precipitate was collected by filtration, washed with a small amount of methanol, and then vacuum-dried to obtain 10.34 g of Intermediate [E]. The obtained intermediate [E] was purified by silica gel column chromatography using a heptane-toluene mixed developing solvent.

Synthesis of Intermediate [F]

Into a 300 mL three-necked flask, put 5.59 g (10.0 mmol) of intermediate [E], 3.01 g (10.5 mmol) of 9-phenylcarbazole-3-boronic acid, 100 mL of 1,2-dimethoxyethane, and 2M phosphoric acid 7.5 mL (15.0 mmol) of a tripotassium aqueous solution was purged with nitrogen in the container. To this mixture was added 0.070 g (0.10 mmol) of bis(triphenylphosphine)palladium(II) chloride, and the mixture was heated and refluxed in an oil bath at 90°C for 7 hours. After the reaction is over, After cooling to room temperature, 100 mL of water was added to the contents of the flask, and the precipitated solid was collected by filtration to obtain 6.56 g of Intermediate [F]. The obtained solid was dissolved in toluene and purified by silica gel column chromatography using a heptane-toluene mixed developing solvent.

Synthesis of Compound [3]

In a 100 mL three-necked flask, 3.61 g (5.00 mmol) of intermediate [F], 0.641 g (5.25 mmol) of phenylboronic acid, 50 mL of 1,4-dioxane, and 3.8 mL (7.5 mmol) of 2M aqueous solution of potassium phosphate were placed, The inside of the container was replaced with nitrogen. To this mixture were added 0.046 g (0.050 mmol) of tris(dibenzylideneacetone)dipalladium(0) and 0.028 g (0.10 mmol) of tricyclohexylphosphine, and the mixture was heated under reflux in an oil bath at 110°C for 4 hours. After completion of the reaction, the mixture was cooled to room temperature, 50 mL of water was added, and the precipitated solid was collected by filtration to obtain 3.57 g of compound [3]. The obtained solid was dissolved in toluene and purified by silica gel column chromatography. Further, the purified product was dissolved by heating in 40 mL of butyl acetate, cooled, recrystallized, collected by filtration, and then vacuum-dried to obtain 3.28 g of compound [3] as a yellow-white solid.

The obtained yellow-white solid was confirmed to be compound [3] by mass spectrometry (JMS-Q1000TD manufactured by JEOL Ltd.).

Compound [3] was used as a light-emitting element material after being purified by sublimation at about 350° C. under a pressure of 1×10 ⁻³ Pa using an oil diffusion pump.

Compounds [4] to [41] used in the following examples can also be synthesized and purified from the starting materials corresponding to the respective compounds using methods similar to those described in Synthesis Example 1 to Synthesis Example 3. .

Example 1

A glass substrate (manufactured by Geomatec Co., Ltd., 11Ω/□, sputtered product) on which the ITO transparent conductive film of 165 nm was deposited was cut into a size of 38 mm×46 mm, and etched. The obtained substrate was ultrasonically cleaned with "Semico Clean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then cleaned with ultrapure water. The substrate was subjected to ultraviolet (Ultraviolet, UV)-ozone treatment for 1 hour immediately before production of the light-emitting element, set in a vacuum deposition apparatus, and evacuated until the degree of vacuum in the apparatus became 5×10 ^-4 Pa or less. By the resistance heating method, 5 nm HAT-CN ₆ was first evaporated as a hole injection layer, and then 50 nm HT-1 was evaporated as a hole transport layer. Next, a mixed layer of the host material H-1 and the dopant material D-1 was vapor-deposited to a thickness of 20 nm so that the doping concentration was 5% by weight as a light-emitting layer. Next, compound [1] was vapor-deposited as an electron transport layer with a thickness of 35 nm. Next, after 0.5 nm of lithium fluoride was vapor-deposited, aluminum was vapor-deposited to 1,000 nm to form a cathode, and a light-emitting element of 5 mm×5 mm square was produced. The film thickness mentioned here is a value displayed by a quartz oscillation type film thickness monitor, and is also common to other Examples and Comparative Examples. The characteristics of this light-emitting element at the time of lighting at a luminance of 1000 cd/m ² were a driving voltage of 4.11 V and an external quantum efficiency of 5.63%. In addition, when the initial brightness was set to 1000 cd/m ² and constant current driving was performed, the time (durability) until the brightness decreased by 20% was 1020 hours. In addition, compound [1], HAT-CN ₆ , HT-1, H-1, and D-1 are the compounds shown below.

Example 2 to Example 32

A light-emitting element was produced and evaluated in the same manner as in Example 1, except that the compounds described in Table 1 were used for the electron transport layer. The results are shown in Table 1. In addition, compound [2] - compound [32] are the compounds shown below.

[Chemical 27]

Comparative Example 1 to Comparative Example 12

A light-emitting element was produced and evaluated in the same manner as in Example 1, except that the compounds described in Table 1 were used for the electron transport layer. The results are shown in Table 1. In addition, E-1 to E-12 are the compounds shown below.

Example 33

A glass substrate (manufactured by Geomatec Co., Ltd., 11Ω/□, sputtered product) on which the ITO transparent conductive film of 165 nm was deposited was cut into a size of 38 mm×46 mm, and etched. The obtained substrate was ultrasonically cleaned with "Semico Clean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then cleaned with ultrapure water. Immediately before production of the light-emitting element, the substrate was subjected to UV-ozone treatment for 1 hour, set in a vacuum vapor deposition apparatus, and evacuated until the degree of vacuum in the apparatus became 5×10 ⁻⁴ Pa or less. By the resistance heating method, firstly, 5 nm HAT-CN ₆ was vapor-deposited as a hole injection layer, and then 40 nm HT-1 was vapor-deposited as a hole transport layer. Next, 10 nm of HT-2 was vapor-deposited as a hole transport layer for blue. Next, a mixed layer of the host material H-1 and the dopant material D-1 was vapor-deposited to a thickness of 20 nm so that the doping concentration was 5% by weight as a light-emitting layer. Next, compound [1] was vapor-deposited as a first electron transport layer with a thickness of 25 nm. Furthermore, compound E-13 was used as the electron transport material, and 2E-1 was used as the donor material, and the vapor deposition rate ratio of E-13 and 2E-1 was E-13:2E-1=1:1. A thickness of 10 nm was laminated as the second electron transport layer. Next, after 0.5 nm of lithium fluoride was vapor-deposited, aluminum was vapor-deposited to 1,000 nm to form a cathode, and a light-emitting element of 5 mm×5 mm square was produced. The characteristics of this light-emitting element at the time of lighting at a luminance of 1000 cd/m ² were a driving voltage of 3.97 V and an external quantum efficiency of 6.30%. In addition, when the initial luminance was set to 1000 cd/m ² and constant current driving was performed, the time required for the luminance to decrease by 20% was 1710 hours. In addition, HT-2, E-13, and 2E-1 are the compounds shown below.

Example 34 to Example 50

A light-emitting element was produced and evaluated in the same manner as in Example 33, except that the compounds described in Table 2 were used for the host material and the first electron transport layer, respectively. The results are shown in Table 2. In addition, H-2 and H-3 are compounds shown below.

Comparative Example 13 to Comparative Example 48

A light-emitting element was produced and evaluated in the same manner as in Example 21, except that the compounds described in Table 2 were used for the host material and the first electron transport layer, respectively. The results are shown in Table 2.

Example 51

A glass substrate (manufactured by Geomatec Co., Ltd., 11Ω/□, sputtered product) on which the ITO transparent conductive film of 165 nm was deposited was cut into a size of 38 mm×46 mm, and etched. The obtained substrate was ultrasonically cleaned with "Semico Clean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then cleaned with ultrapure water. Immediately before production of the light-emitting element, the substrate was subjected to UV-ozone treatment for 1 hour, set in a vacuum vapor deposition apparatus, and evacuated until the degree of vacuum in the apparatus became 5×10 ^-4 Pa or less. By the resistance heating method, firstly, 5 nm HAT-CN ₆ was vapor-deposited as a hole injection layer, and then 40 nm HT-1 was vapor-deposited as a hole transport layer. Next, 10 nm of HT-2 was vapor-deposited as a hole transport layer for blue. Next, a mixed layer of the host material H-1 and the dopant material D-1 was vapor-deposited to a thickness of 20 nm so that the doping concentration was 5% by weight as a light-emitting layer. Next, compound [1] was vapor-deposited as a first electron transport layer with a thickness of 25 nm. Furthermore, compound E-14 was used as the electron transport material, and 2E-1 was used as the donor material, and the vapor deposition rate ratio of E-14 and 2E-1 was E-14:2E-1=1:1. A thickness of 10 nm was laminated as the second electron transport layer. Next, after 0.5 nm of lithium fluoride was vapor-deposited, aluminum was vapor-deposited to 1,000 nm to form a cathode, and a 5 mm×5 mm square element was produced. The characteristics of this light-emitting element at the time of lighting at a luminance of 1000 cd/m ² were a driving voltage of 4.21 V and an external quantum efficiency of 7.52%. In addition, when the initial luminance was set to 1000 cd/m ² and constant current driving was performed, the time required for the luminance to decrease by 20% was 2050 hours. In addition, E-14 is the compound shown below.

Example 52 to Example 68

A light-emitting element was produced and evaluated in the same manner as in Example 51, except that the compounds described in Table 3 were used as the first electron transport layer and the second electron transport layer, respectively. The results are shown in Table 3. E-15 and E-16 are compounds shown below.

Comparative Example 49 to Comparative Example 84

A light-emitting element was produced and evaluated in the same manner as in Example 51, except that the compounds described in Table 3 were used as the first electron transport layer and the second electron transport layer, respectively. The results are shown in Table 3.

Example 69

A glass substrate (manufactured by Geomatec Co., Ltd., 11Ω/□, sputtered product) on which the ITO transparent conductive film of 90 nm was deposited was cut into 38 mm×46 mm, and etched. The obtained substrate was ultrasonically cleaned with "Semico Clean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then cleaned with ultrapure water. Immediately before the device was fabricated, the substrate was subjected to UV-ozone treatment for 1 hour, set in a vacuum vapor deposition apparatus, and evacuated until the degree of vacuum in the apparatus became 5×10 ⁻⁴ Pa or less. By the resistance heating method, 10 nm HAT-CN ₆ was evaporated as a hole injection layer. Next, 110 nm of HT-1 was evaporated as the first hole transport layer. Next, 20 nm of compound HT-2 was evaporated as the second hole transport layer. Next, compound H-4 was used as the host material, and compound D-2 was used as the dopant material, and the dopant material was vapor-deposited to a thickness of 40 nm so that the doping concentration of the dopant material was 10% by weight as a light-emitting layer. Next, compound [1] was vapor-deposited as a first electron transport layer with a thickness of 25 nm. Furthermore, compound E-14 was used as the electron transport material, and compound 2E-1 was used as the donor material, so that the vapor deposition rate ratio of E-14 and 2E-1 was E-14:2E-1=1:1 The second electron transport layer was laminated with a thickness of 20 nm.

Next, after 1 nm of compound 2E-1 was vapor-deposited, a co-evaporated film of magnesium and silver was vapor-deposited to 60 nm at a vapor deposition rate ratio of magnesium:silver=10:1 (=0.5nm/s:0.05nm/s). A cathode is made to make a 5mm × 5mm square element. The film thickness mentioned here is the value displayed by the quartz oscillator film thickness monitor. This light-emitting element was driven at a direct current of 10 mA/cm ² , and as a result, green light emission with a luminous efficiency of 45.3 m/W was obtained. In addition, regarding the luminous efficiency (lm/W), it is based on the front luminance (cd/cm ² ) obtained by the measurement with the spectroradiometer (CS-1000, the Konica Minolta company make), Calculated from the power density (W/cm ² ) and radiation angle (sr, solid angle) put into the element. This light-emitting element was continuously driven at a direct current of 10 mA/cm ² , and as a result, the luminance was reduced by half at 5430 hours. In addition, H-4 and D-2 are compounds shown below.

Example 70 ~ Example 74

A light-emitting element was produced and evaluated in the same manner as in Example 69, except that the compounds described in Table 4 were used in the first electron transport layer. The results are shown in Table 4.

Comparative Example 85 to Comparative Example 96

A light-emitting element was produced and evaluated in the same manner as in Example 69, except that the compounds described in Table 4 were used in the first electron transport layer. The results are shown in Table 4.

[Table 2-3]

[Table 3-3]

Claims (18)

A compound represented by the following general formula (1),

In formula (1), L ¹ is a single bond, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group; L ² is a substituted or unsubstituted aryl group; L ¹ is connected at any position in X ¹ ~X ⁸ and R ⁵⁵ , L ² is connected at any position in X ⁹ ~X ¹⁶ and R ⁵⁶ ; wherein, L ¹ is connected at the position of R ⁵⁵ , And the case where L ² is linked at the position of R ⁵⁶ is excluded; R ⁵¹ to R ⁵⁴ are independently selected from hydrogen atom, alkyl group, cycloalkyl group, heterocyclyl group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group group, alkylthio group, aryl ether group, aryl sulfide group, aryl group, heteroaryl group, halogen atom, cyano group, amine group, carbonyl group, carboxyl group, oxycarbonyl group, carbamoyl group and -P(= O) In the group formed by R ⁵⁷ R ⁵⁸ ; R ⁵⁷ and R ⁵⁸ are aryl or heteroaryl groups, and R ⁵⁷ and R ⁵⁸ can also be condensed to form a ring; R ⁵⁵ and R ⁵⁶ are selected from hydrogen atoms, alkanes In the group consisting of base, cycloalkyl, heterocyclyl, alkenyl, cycloalkenyl, aryl and heteroaryl; X ⁿ (n=1~16) are respectively CR ⁿ (n=1~16) or nitrogen atom; R ⁿ (n=1~16) is independently selected from hydrogen atom, alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl ether group , an aryl sulfide group, a halogen atom, a cyano group, an amino group, a carbonyl group, a carboxyl group, an oxycarbonyl group, a carboxyl group and a group consisting of -P(=O)R ¹⁷ R ¹⁸ ; R ¹⁷ and R ¹⁸ is an aryl group or a heteroaryl group, and R ¹⁷ and R ¹⁸ may be condensed to form a ring. The compound according to claim 1, wherein in the general formula (1), L ¹ is a single bond. The compound according to item 1 or item 2 of the claimed scope, wherein in the general formula (1), L ² is a substituted or unsubstituted phenylene group. The compound according to item 1 of the claimed scope, wherein in the general formula (1), L ¹ is a substituted or unsubstituted aryl group. A compound represented by the following general formula (1),

In formula (1), L ¹ is a substituted or unsubstituted aryl group; L ² is a single bond; L ¹ is linked at any position in X ¹ ~X ⁸ and R ⁵⁵ , L ² is at X ⁹ Any position in ~ ^X16 and ^R56 is connected; wherein, L1 is connected at the position ^{of R55} , and L2 is connected ^{at the position of R56 except} for the case; ^R51 ~ ^R54 are independently selected from Hydrogen atom, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl ether group, aryl sulfide group, aryl group, heteroaryl group, In the group consisting of halogen atom, cyano group, amino group, carbonyl group, carboxyl group, oxycarbonyl group, carbamoyl group and -P(=O)R ⁵⁷ R ⁵⁸ ; R ⁵⁷ and R ⁵⁸ are aryl or heteroaryl R ⁵⁷ and R ⁵⁸ can also be condensed to form a ring; R ⁵⁵ and R ⁵⁶ are selected from hydrogen atoms, alkyl groups, cycloalkyl groups, heterocyclic groups, alkenyl groups, cycloalkenyl groups, aryl groups and heteroaryl groups In the group consisting of; X ⁿ (n=1~16) are respectively CR ⁿ (n=1~16) or nitrogen atoms; R ⁿ (n=1~16) are independently selected from hydrogen atoms, alkyl groups, Cycloalkyl, alkenyl, cycloalkenyl, alkynyl, alkoxy, alkylthio, aryl ether, aryl sulfide, halogen atom, cyano, amine, carbonyl, carboxyl, oxycarbonyl, In the group consisting of carbamoyl and -P(=O)R ¹⁷ R ¹⁸ ; R ¹⁷ and R ¹⁸ are aryl or heteroaryl, and R ¹⁷ and R ¹⁸ can also be condensed to form a ring. The compound according to claim 1 or claim 5, wherein in the general formula (1), L ¹ is linked at the position of X ³ . The compound according to claim 1 or claim 5, wherein in the general formula (1), L ² is linked at the position of X ¹⁴ . The compound according to item 1 or item 5 of the claimed scope, wherein in the general formula (1), L ¹ is a substituted or unsubstituted phenylene group. The compound according to claim 1 or claim 5, wherein in the general formula (1), any one of X ⁿ (n=1~16) is CR ⁿ (n=1~16) In the case of , the R ⁿ are all hydrogen atoms. An electronic component containing the compound described in any one of the first to ninth claims in the scope of application. An organic thin film light-emitting element, which has an anode and a cathode, and an organic layer between the anode and the cathode, and emits light by electric energy, wherein the organic thin-film light-emitting element contains in the organic layer such as The compound described in any one of items 1 to 9 of the patent application scope. The organic thin-film light-emitting element according to claim 11, wherein the organic layer has at least a light-emitting layer and an electron transport layer, and the electron transport layer contains any one of items 1 to 9 of the claimed scope the compound. The organic thin-film light-emitting element according to the claim 12, wherein the electron transport layer comprises two or more layers, and the side in contact with the light-emitting layer of these comprises the light-emitting element according to the claim 1 to claim 9. The compound of any one. The organic thin-film light-emitting element according to claim 13, wherein the layer in contact with the cathode side of the electron transport layer contains a compound having a phenanthroline skeleton, a pyrene skeleton, or a fluoranthene skeleton. The organic thin-film light-emitting element according to any one of items 12 to 14 of the claimed scope, wherein the light-emitting layer contains at least one compound having an anthracene skeleton. The organic thin-film light-emitting element according to any one of the claims 12 to 14, wherein the light-emitting layer has at least one light-emitting layer containing at least one phosphorescent light-emitting material. A display device comprising the organic thin-film light-emitting element according to any one of items 11 to 16 of the application scope. A lighting device comprising the organic thin-film light-emitting element according to any one of items 11 to 16 of the patent application scope.