JP6954275B2 - Compounds, electronic devices containing them, organic thin film light emitting devices, display devices and lighting devices - Google Patents

Description

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

An organic thin film light emitting device is an element that emits light when electrons injected from a cathode and holes injected from an anode recombine in an organic fluorescent body sandwiched between both electrodes. Research on the organic thin film light emitting device has been actively conducted in recent years. The organic thin film light emitting element is thin, can obtain high brightness light emission under a low driving voltage, and can emit multiple colors by appropriately selecting a light emitting material such as a fluorescent light emitting material or a phosphorescent light emitting material. It is a feature that it is.

In recent years, organic thin-film light-emitting devices have been steadily put into practical use, such as being used in the main display of mobile phones. However, there are still many technical problems with existing organic thin film light emitting devices. Above all, achieving both high-efficiency light emission and long life of the organic thin-film light-emitting element has become a major issue.

As a compound for solving 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, “nitrogen-containing aromatic heterocycle”), has been developed (for example). , Patent Documents 1 and 2 and Non-Patent Document 1).

International Publication No. 2006/049013 Special Table 2016-508131

Days and Pigments 125 (2016) 299

However, with the compounds described in Patent Documents 1 and 2 or Non-Patent Document 1 described above, it has been difficult to sufficiently reduce the driving voltage of the organic thin film light emitting device. Further, even if the drive voltage can be lowered, the luminous efficiency and the durable life of the organic thin film light emitting element are insufficient. As described above, no technology has been found that exhibits excellent performance in all of luminous efficiency, drive voltage, and durable life.

An object of the present invention is to solve the problems of the prior art and to provide an organic thin film light emitting device having improved luminous efficiency, driving voltage, and durable life.

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

In formula (1), L ¹ and L ² are single-bonded, substituted or unsubstituted arylene groups, or substituted or unsubstituted heteroarylene groups. L ¹ is connected at any one of X ^{1 to} X ⁸ and R ^{55 , and L 2} is connected at any one of ^{X 9 to} X ¹⁶ and R ⁵⁶ . However, this is not the ^{case when L 1} is connected at the position of ^{R 55 and L 2} is connected at the position of ^{R 56.}
Either L ¹ or L ² is always a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group.
R ^{51 to} R ⁵⁴ are independently hydrogen atom, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl ether group, aryl thio ether group, and aryl. It is selected from the group consisting of a group, a heteroaryl group, a halogen atom, a cyano group, an amino group, a carbonyl group, a carboxy group, an oxycarbonyl group, a carbamoyl 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 fused to form a ring.
R ⁵⁵ and R ⁵⁶ are selected from the group consisting of hydrogen atom, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, aryl group and heteroaryl group.
X ⁿ (n = 1-16) is CR ⁿ (n = 1-16) or a nitrogen atom, respectively.
R ⁿ (n = 1 to 16) independently contains a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an alkoxy group, an alkylthio group, an aryl ether group, an aryl thio ether group, and a halogen. It is selected from the group consisting of an atom, a cyano group, an amino group, a carbonyl group, a carboxy group, an oxycarbonyl group, a carbamoyl 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 fused to form a ring.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an organic thin film light emitting device excellent in terms of high luminous efficiency, low driving voltage and long durable life.

Hereinafter, preferred embodiments of the compound according to the present invention, an electronic device containing the compound, 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 variously modified and implemented according to an object and an application.

<Compound represented by the general formula (1)>
The compound represented by the general formula (1), which is one embodiment of the present invention, is shown below.

In formula (1), L ¹ and L ² are single-bonded, substituted or unsubstituted arylene groups, or substituted or unsubstituted heteroarylene groups. L ¹ is connected at any one of X ^{1 to} X ⁸ and R ^{55 , and L 2} is connected at any one of ^{X 9 to} X ¹⁶ and R ⁵⁶ . However, this is not the ^{case when L 1} is connected at the position of ^{R 55 and L 2} is connected at the position of ^{R 56.}
Either L ¹ or L ² is always a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group.
R ^{51 to} R ⁵⁴ are independently hydrogen atom, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl ether group, aryl thio ether group, and aryl. It is selected from the group consisting of a group, a heteroaryl group, a halogen atom, a cyano group, an amino group, a carbonyl group, a carboxy group, an oxycarbonyl group, a carbamoyl 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 fused to form a ring.
R ⁵⁵ and R ⁵⁶ are selected from the group consisting of hydrogen atom, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, aryl group and heteroaryl group.
X ⁿ (n = 1-16) is CR ⁿ (n = 1-16) or a nitrogen atom, respectively.
R ⁿ (n = 1 to 16) independently contains a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an alkoxy group, an alkylthio group, an aryl ether group, an aryl thio ether group, and a halogen. It is selected from the group consisting of an atom, a cyano group, an amino group, a carbonyl group, a carboxy group, an oxycarbonyl group, a carbamoyl 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 fused to form a ring.

In all the above groups, the hydrogen may be deuterium. Further, in the following description, for example, the substituted or unsubstituted aryl group having 6 to 40 carbon atoms is 6 to 40 including the carbon number contained in the substituent substituted with the aryl group. The same applies to other substituents that specify the number of carbon atoms.

Further, as the substituent in the case of "substituted or unsubstituted", as described above, an alkyl group, a cycloalkyl group, a heterocyclic group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an alkoxy group, an alkylthio group and an aryl group. An ether group, an arylthioether group, an aryl group, a heteroaryl group, a halogen atom, a cyano group, an amino group, a carbonyl group, a carboxy group, an oxycarbonyl group and a carbamoyl group are preferable, and further, they are preferable in the description of each substituent. , Specific substituents are preferred. Further, these substituents may be further substituted with the above-mentioned substituents.

The same applies to the case of "substituent or unsubstituted" in the compound or its partial structure described below.

The alkyl group indicates a saturated aliphatic hydrocarbon group such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group and a tert-butyl group. 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, and a heteroaryl group, and this point is also common to the following description. The number of carbon atoms of the alkyl group is not particularly limited, but is preferably in the range of 1 or more and 20 or less, more preferably 1 or more and 8 or less, from the viewpoint of availability and cost.

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

The alkenyl group refers to an unsaturated aliphatic hydrocarbon group containing 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 carbon number of the alkenyl group is not particularly limited, but is preferably in the range of 2 or more and 20 or less.

The cycloalkenyl group refers to 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 of the cycloalkenyl group is not particularly limited, but is preferably in the range of 4 or more and 20 or less.

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

The alkoxy group refers to a functional group in which an aliphatic hydrocarbon group is bonded via an ether bond, such as a methoxy group, an ethoxy group, and a propoxy group. This aliphatic hydrocarbon group may or may not have a substituent. The number of carbon atoms of the alkoxy group is not particularly limited, but is preferably in 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 replaced with a sulfur atom. The hydrocarbon group of the alkylthio group may or may not have a substituent. The number of carbon atoms of 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 refers to a functional group to which an aromatic hydrocarbon group is bonded via an ether bond, for example, a phenoxy group. This aromatic hydrocarbon group may or may not have a substituent. The number of carbon atoms of the aryl ether group is not particularly limited, but is preferably in the range of 6 or more and 40 or less.

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

The aryl group refers to an aromatic hydrocarbon group such as a phenyl group, a naphthyl group, a biphenyl group, a terphenyl group, a phenanthryl group, an anthracenyl group, a pyrenyl group, and a fluoranthenyl group. The aryl group may or may not have a substituent. The number of carbon atoms of 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.

Heteroaryl groups are flanyl group, thiophenyl group, pyridyl group, quinolinyl group, isoquinolinyl group, pyrazinyl group, pyrimidyl group, naphthylyl group, benzofuranyl group, benzothiophenyl group, indolyl group, dibenzofuranyl group and dibenzothiophenyl group. , A cyclic aromatic group having one or more atoms other than carbon, such as a carbazolyl group, in the ring. The heteroaryl group may or may not have a substituent. The number of carbon atoms of 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 dibenzothiophenyl group.

The amino group is a substituted or unsubstituted amino group. Examples of the substituent in the case of substitution include an aryl group, a heteroaryl group, a linear alkyl group and a branched alkyl group. More specifically, a phenyl group, a biphenyl group, a naphthyl group, a pyridyl group, a methyl group and the like can 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 refers to an atom selected from fluorine, chlorine, bromine and iodine.

The carbonyl group, carboxy group, oxycarbonyl group, carbamoyl group and phosphine oxide group may or may not have a substituent. Here, examples of the substituent include an alkyl group, a cycloalkyl group, an aryl group, a heteroaryl group and the like, and these substituents may be further substituted.

The arylene group refers to a divalent or higher valent group derived from an aromatic hydrocarbon group such as benzene, naphthalene, biphenyl, fluorene, or phenanthrene. The arylene group may or may not have a substituent. A preferred arylene group is a divalent or trivalent arylene group. Specific examples of the arylene group include a phenylene group, a biphenylene group, a naphthylene group, and a fluorenylene group. More specifically, 1,4-phenylene group, 1,3-phenylene group, 1,2-phenylene group, 4,4'-biphenylene group, 4,3'-biphenylene group, 3,3'-biphenylene group. , 1,4-naphthalenylene group, 1,5-naphthalenylene group, 2,5-naphthalenylene group, 2,6-naphthalenylene group, 2,7-naphthalenylene group, 1,3,5-phenylene group and the like. More preferably, it is a 1,4-phenylene group, a 1,3-phenylene group, a 4,4'-biphenylene group, or a 4,3'-biphenylene group.

A heteroarylene group is a divalent or higher valent derived from an aromatic group having one or more atoms other than carbon, such as pyridine, quinoline, pyrimidine, pyrazine, triazine, quinoxaline, quinazoline, dibenzofuran, and dibenzothiophene. Shows the basis of. The heteroarylene group may or may not have a substituent. The preferred heteroarylene group is a divalent or trivalent heteroarylene group. The carbon number of the heteroarylene group is not particularly limited, but is preferably in the range of 2 or more and 30 or less. Specific examples of the heteroarylene group include 2,6-pyridylene group, 2,5-pyridylene group, 2,4-pyridylene group, 3,5-pyridylene group, 3,6-pyridylene group, 2,4. 6-Pyridylene group, 2,4-pyrimidinylene group, 2,5-pyrimidinylene group, 4,6-pyrimidinylene group, 2,4,6-pyrimidinylene group, 2,4,6-triadinylene group, 4,6-dibenzofurani Examples thereof include a len group, a 2,6-dibenzofuranylene group, a 2,8-dibenzofuranylene group and a 3,7-dibenzofuranylene group.

Since the quinazoline skeleton has ^two nitrogen atoms forming sp2 hybrid orbitals with high electronegativity, it has high affinity with electrons and high electron transportability. Therefore, when a compound having a quinazoline skeleton is used for the electron injection layer of the organic thin film light emitting device, electron injection from the cathode to the electron injection layer is likely to occur.

Further, when a compound having a quinazoline skeleton is used for the electron transport layer of the organic thin film light emitting device, the electron transport layer exhibits high electron transport property. However, in a general organic thin film light emitting element, the LUMO energy level of a molecule consisting only of a quinazoline skeleton is too low as compared with the lowest empty orbital (LUMO) energy level of the light emitting layer. Therefore, the electron injection 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). This is because the carbazole skeleton has the property of increasing the LUMO energy level and has good electron transport properties. Introducing a carbazole skeleton into a compound having a quinazoline skeleton enhances the low LUMO energy level derived from the quinazoline skeleton. Therefore, when such a compound is used in the electron transport layer, the electron injection input to the light emitting layer can be enhanced.

In addition, the carbazole skeleton and the quinazoline skeleton have the property of having high charge transportability within the skeleton. In compounds that combine these skeletons, the highest occupied molecular orbital (HOMO) and LUMO spread intramolecularly. When the spread of HOMO and LUMO in the molecule becomes large, the overlap of the orbitals with the adjacent molecule also becomes large, and the charge transportability is improved. Therefore, when the compound represented by the general formula (1) is used in any of the layers constituting the organic thin film light emitting device, electrons generated from the cathode and holes generated from the anode can be efficiently transported. The drive voltage of the organic thin film light emitting element can be reduced. As a result, the luminous efficiency of the organic thin film light emitting device can be improved.

Further, in the compound represented by the general formula (1), the radicals generated when receiving an electric charge are stabilized by expanding the molecular orbital. Moreover, in the first place, the carbazole skeleton and the quinazoline skeleton have high charge stability, that is, electrochemical stability. Therefore, when the compound represented by the general formula (1) is used in any of the layers constituting the organic thin film light emitting device, the durable life of the organic thin film light emitting device is improved.

In addition, both the carbazole skeleton and the quinazoline skeleton have a rigid structure in which a plurality of rings are condensed. Therefore, compounds having these skeletons exhibit high glass transition temperatures. Further, when sublimating such a compound, due to its rigid structure, each molecule is not entangled and sublimates stably. As described above, since the glass transition temperature of the compound represented by the general formula (1) is high, the heat resistance of the organic thin film light emitting device is improved. Further, since a high-quality film formed by stable sublimation of the compound represented by the general formula (1) can be obtained, the durable life of the organic thin film light emitting device is improved.

These effects are not sufficient when the quinazoline skeleton is replaced by a single carbazole skeleton. By substituting two carbazole skeletons for the quinazoline skeleton, a sufficiently large effect can be obtained.

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 drive voltage and long durability life are all possible. ..

In particular, the compound represented by the general formula (1) is preferably used for the light emitting layer or the electron transporting layer of the organic thin film light emitting device because of its characteristics, and among them, it is particularly preferable to use it for the electron transporting layer.

In the general formula (1), L ¹ is connected at any one of ^{X 1 to} X ⁸ and R ^{55 , and L 2} is ^{connected at any one of X 9 to} X ¹⁶ and R ^56. ..

Here, for example, when L ¹ is connected at the position of ^{X 1 , it means that X 1} is CR ¹ , but R ¹ itself does not exist, and L ¹ and a carbon atom are directly bonded. Further, when L ¹ is connected at the position of ^{R 55 , it means that R 55} itself does not exist and the nitrogen atom of the carbazol skeleton and L ¹ are directly bonded.

The positions L ¹ and L ² of the quinazoline skeleton are substitution positions in the quinazoline skeleton on the six-membered ring having an electron-attracting nitrogen atom. The low LUMO energy levels from the quinazoline skeleton are distributed on a six-membered ring with electron-attracting nitrogen atoms. Therefore, when a carbazole skeleton is bound to this position, the effect of increasing the LUMO energy level of the compound is great. Thereby, as described above, the electronic injection input can be enhanced.

In the general formula (1), ^{it is preferable that L 1} is connected at the position of ^{X 3.} Further, ^{it is preferable that L 2} is connected at the position of ^{X 14.} This is because the effect of increasing the LUMO energy level of the compound becomes particularly large when they are linked at these positions.

However, in the general formula (1), except when L ¹ is connected at the position of ^{R 55 and L 2} is connected at the position of ^{R 56.} This is because when the quinazoline skeleton is linked to the nitrogen atom of the carbazole skeleton, the effect of raising the LUMO energy level of the compound is small. When only one of the two carbazole skeletons is linked by its nitrogen atom and the quinazoline skeleton, the effect of increasing the LUMO energy level of the compound can be maintained. However, when both of the two carbazole skeletons are linked by the nitrogen atom and the quinazoline skeleton, the effect cannot be maintained, so that the electron injection input of the compound becomes small.

Either L ¹ or L ² is always a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene 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 device is improved.

L ¹ and L ² are single-bonded, substituted or unsubstituted arylene groups, or substituted or unsubstituted heteroarylene groups. When L ¹ and L ² are substituted arylene groups or substituted heteroarylene groups, the substituents are as described above, but preferably an alkyl group, a cycloalkyl group, a heterocyclic group, an aryl ether group, or an aryl. It is a thioether group, an aryl group, a heteroaryl group, a halogen atom, a cyano group, or an amino group, more preferably a heterocyclic group, an aryl group, a heteroaryl group, a halogen atom, a cyano group, or an amino group, and further. Preferably, it is an aryl group, a heteroaryl group, or an amino group.

The L ¹ and L ² are more preferably a single bond and an arylene group having 6 to 24 carbon atoms, and further preferably a single bond and a phenyl group. L ¹ and L ² are connecting groups that form around the quinazoline skeleton that forms the LUMO level, which is the electron conduction level. Therefore, single bonds and arylene groups, which have a small effect on the LUMO level of quinazoline, are preferable. In addition, single bonds and phenyl groups, which have a small bulk and a higher electron transport property between molecules, 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 arylene group or a substituted or unsubstituted heteroarylene group. In this case, L ² is preferably a substituted or unsubstituted arylene group, and L ² is more preferably a substituted or unsubstituted phenylene group.

Further, in the general formula (1), ^{it is preferable that L 2} is a single bond and L ¹ is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group. In this case, L ¹ is preferably a substituted or unsubstituted arylene group, and L ¹ is more preferably a substituted or unsubstituted phenylene group.

^{If only one of} L 1 and L ² is a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, the effect of increasing the LUMO energy level by the binding of the carbazole skeleton becomes greater. Is.

^{Further, X n} (n = 1 to 16) on the carbazole skeleton ^{is C-R n} (n = 1 to 16) or a nitrogen atom, respectively. R ⁿ (n = 1 to 16) independently contains a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an alkoxy group, an alkylthio group, an aryl ether group, an aryl thio ether group, and a halogen. It is selected from the group consisting of an atom, a cyano group, an amino group, a carbonyl group, a carboxy group, an oxycarbonyl group, a carbamoyl group and -P (= O) R ¹⁷ R ^18.

Substituents other than the hydrogen atom are introduced to modify the electronic state of the carbazole skeleton. For example, an aromatic heterocyclic group containing an oxygen atom (hereinafter, "oxygen-containing aromatic heterocyclic group") or an aromatic heterocyclic group containing a sulfur atom (hereinafter, "sulfur-containing aromatic heterocyclic group"). The electron-donating substituent reinforces the electron-donating property of the carbazole skeleton. On the other hand, an electron-attracting substituent such as a cyano group reduces the electron-donating property of the carbazole skeleton.

Among these substituents, a particularly preferable R ⁿ (n = 1 to 16) is a hydrogen atom. This is because when R ⁿ (n = 1 to 16) is a hydrogen atom, the bulk around the quinazoline skeleton forming the LUMO level, which is the electron conduction level, becomes small, and the electron transportability between molecules is further improved. ..

R ^{51 to} R ⁵⁴ are as described above, but preferably hydrogen atom, cycloalkyl group, heterocyclic group, aryl ether group, aryl thioether group, aryl group, heteroaryl group, halogen atom, cyano group, and amino. It is a group, more preferably a hydrogen atom, an aryl group, a heteroaryl group, a halogen atom, a cyano group, and an amino group, and particularly preferably a hydrogen atom. R ⁵⁵ and R ⁵⁶ are as described above, but are preferably aryl groups.

The LUMO energy level of the compound represented by the general formula (1) is slightly lower than the LUMO energy level of the material having an anthracene skeleton, which is often used as a host material for the blue light emitting layer. Therefore, in the organic thin film light emitting device, it is preferable to use a compound having an anthracene skeleton for the light emitting layer, particularly 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 device, electron injection into the blue light emitting layer is appropriately suppressed. Along with this, it is suppressed that the inside of the light emitting layer is in a state of excess electrons, and the carrier balance is adjusted. As a result, the luminous efficiency and durable life of the organic thin film light emitting element are improved.

In addition, the compound represented by the general formula (1) easily receives 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, in the organic thin film light emitting element, a compound having a pyrene skeleton, a compound having a phenanthroline skeleton, or a compound having a fluoranthene skeleton is used for the layer in contact with the cathode side of the layer containing the compound represented by the general formula (1). Is preferable. Such an organic thin film light emitting device can be driven at a low voltage.

It is more preferable that the compound having a pyrene skeleton has an aryl group substituted or unsubstituted at the 1st and 6th positions or a heteroaryl group because the electron transport property is increased.

It is more preferable that the compound having a phenanthroline skeleton has a plurality of phenanthroline skeletons in the molecule in order to disperse charges and accelerate electron transfer.

The compound having a fluoranthene skeleton is more preferably a compound having a fluoranthene skeleton and an amino group because it enhances the deep LUMO energy of the fluoranthene skeleton.

The compound represented by the general formula (1) is not particularly limited, and specific examples thereof include the following.

A known method can be used for the synthesis of the compound represented by the general formula (1). The carbazole skeleton is commercially available with a halogen atom or boronic acid bonded thereto. Examples of the synthesis method include a method using a coupling reaction between a substituted or unsubstituted carbazolylboronic acid derivative and a substituted or unsubstituted quinazoline halide derivative under a palladium catalyst or a nickel catalyst, or a substitution method. Alternatively, a method utilizing a coupling reaction between an unsubstituted or unsubstituted carbazole derivative and a substituted or unsubstituted quinazoline derivative, a substituted or unsubstituted halogenated carbazole derivative, and a substituted or unsubstituted quinazolinylboronic acid derivative. Examples include, but are not limited to, a method using a coupling reaction with.

Boronic acid ester may be used instead of boronic acid. Halogen atoms attached to the carbazole skeleton can be converted to boronic acid esters using known methods. The quinazoline skeleton can be synthesized by a cyclization reaction from a substituted or unsubstituted 2-aminobenzonitrile derivative and a Grignard reagent using a known method. Since halogenated quinazoline is commercially available, it can also be used.

In the compound represented by the general formula (1), the reactivity of L ^{1 is higher in L 1} and L ^{2 of the quinazoline skeleton.} Therefore, by appropriately selecting the catalyst and the reaction temperature, the carbazole binding reaction to quinazoline can be carried out in a regioselective manner.

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

A 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 an electrical signal. Since the compound represented by the general formula (1) has excellent electron transport properties, it is preferably used for the photoelectric conversion layer, and more preferably used for the n-type material of the photoelectric conversion layer.

The light emitting device material represents a material used for any layer of the organic thin film light emitting device. As described later, the light emitting device material includes a material used for a layer selected from a hole transport layer, a light emitting layer, and an electron transport layer, and also a material used for a protective layer (cap layer) of an electrode. included. By using the compound represented by the general formula (1) in any layer of the organic thin film light emitting device, a high luminous efficiency can be obtained, a driving voltage is low, and a highly durable organic thin film light emitting device can be obtained. ..

<Organic thin film light emitting element>
The organic thin film light emitting device according to one embodiment of the present invention will be described in detail below. 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 transporting layer.

Preferred configurations of the organic layer include 1) hole transport layer / light emitting layer / electron transport layer, 2) hole transport layer / light emitting layer / electron transport layer / electron injection, in addition to the configuration of the light emitting layer / electron transport layer. Layers, 3) a laminated structure such as a hole injection layer / a hole transport layer / a light emitting layer / an electron transport layer / an electron injection layer can be mentioned. Further, each of the above layers may be either a single layer or a plurality of layers. Further, it may be a laminated type having a plurality of phosphorescent light emitting layers or fluorescent light emitting layers, or may be a configuration in which a fluorescent light emitting layer and a phosphorescent light emitting layer are combined. Further, it may have a configuration in which light emitting layers exhibiting different emission colors are laminated.

Further, the above-mentioned element configuration may be a tandem type configuration in which a plurality of layers are laminated via an intermediate layer. At least one of the organic layers contained in the tandem type structure is preferably a phosphorescent layer. The intermediate layer is also commonly referred to as an intermediate electrode, an intermediate conductive layer, a charge generating layer, an electron extraction layer, a connecting layer or an intermediate insulating layer. Specific examples of the tandem type configuration include, for example, 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 transport. Charge as an intermediate layer between the anode and the cathode, such as 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. A laminated structure including a generation layer can be mentioned. Specifically, a pyridine derivative, a phenanthroline derivative, or the like is preferably used as the material constituting the intermediate layer. When the material constituting the intermediate layer is a phenanthroline derivative, it is more preferable that the phenanthroline derivative is a compound having two or more phenanthroline skeletons in the molecule.

The organic thin film light emitting device of the present invention (hereinafter, may be referred to as a light emitting device) contains a compound represented by the general formula (1) in an organic layer. The compound represented by the general formula (1) may be used in any layer in the above element configuration, but it has high electron injection transport ability, fluorescence quantum yield and thin film stability. It is preferably used for the light emitting layer, the electron transport layer or the intermediate layer of the light emitting element. In particular, from the viewpoint of excellent electron injecting and transporting ability, the compound represented by the general formula (1) is more preferably used in the electron transporting layer or the intermediate layer, and particularly preferably used in the electron transporting layer.

(substrate)
In order to maintain the mechanical strength of the light emitting element, it is preferable to form the light emitting element on the substrate. As the substrate, a glass substrate such as soda glass or non-alkali glass is preferably used. The thickness of the glass substrate needs to be sufficient to maintain the mechanical strength, and therefore 0.5 mm or more is sufficient. As for the material of the glass, non-alkali glass is preferable because it is preferable that the amount of eluted ions from the glass is small. Further, _{soda lime glass coated with a barrier coat such as SiO 2 is} also commercially available, and this can also be used. Further, as long as the first electrode formed on the substrate functions stably, the substrate does not have to be glass, and may be, for example, a plastic substrate.

(Anode and cathode)
In the organic thin film light emitting device according to the embodiment of the present invention, the anode and the cathode have a role of supplying a sufficient current for light emission of the device. In order to extract light, it is preferable that at least one of the anode and the cathode is transparent or translucent. Usually, the anode formed on the substrate is a transparent electrode.

The material used for the anode is not particularly limited as long as it is a material capable of efficiently injecting holes into the organic layer and is transparent or translucent so that light can be extracted. Examples of the material 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, copper iodide and copper sulfide. Examples thereof include inorganic conductive substances, conductive polymers such as polythiophene, polypyrrole, and polyaniline. These electrode materials may be used alone, or a plurality of materials may be laminated or mixed.

As the substrate on which the anode is formed, it is particularly preferable to use ITO glass having an ITO film formed on the surface of the glass or Nesa glass having a tin oxide-based film formed on the surface of the glass. In the case of ITO glass, the method for forming the ITO film is not particularly limited as long as it is a method capable of forming the ITO film, such as an electron beam method, a sputtering method and a chemical reaction method.

The material used for the cathode is not particularly limited as long as it is a substance capable of efficiently injecting electrons into the light emitting layer. Materials generally include metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, these metals and low work function metals such as lithium, sodium, potassium, calcium and magnesium. Alloys or multi-layer laminates are preferred. Above all, it is preferable that the main component of the material used for the cathode is aluminum, silver or magnesium from the viewpoints of low electric resistance value, ease of film formation, film stability, luminous efficiency and the like. In particular, when the cathode is composed of magnesium and silver, electron injection into the electron transport layer and the electron injection layer becomes easy, and the light emitting element can be driven with a lower voltage, which is preferable. The method for producing these electrodes is not particularly limited, and examples thereof include resistance heating, electron beam, sputtering, ion plating and coating.

(Protective film layer)
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 for example, metals such as platinum, gold, silver, copper, iron, tin, aluminum and indium, alloys using these metals, silica, titania and silicon nitride and the like. Examples thereof include organic polymer compounds such as polyvinyl alcohol, polyvinyl chloride, and hydrocarbon-based polymer compounds. Further, the compound represented by the general formula (1) can also be used as the protective film layer. However, when the light emitting element has an element structure (top emission structure) that extracts light from the cathode side, the material used for the protective film layer is selected from materials having light transmission in the visible light region.

(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. Further, the hole transport material is required to efficiently transport the holes injected from the anode between the electrodes to which an electric field is applied. Therefore, as the hole transport material, a material having high hole injection efficiency and capable of efficiently transporting the injected holes is preferable. For that purpose, a material having an appropriate ionization potential, high hole mobility, and excellent stability is preferable, and impurities that become traps are less likely to be generated during the production and use of such a material. preferable.

The substance satisfying such conditions is not particularly limited, but for example,
4,4'-bis (N- (3-methylphenyl) -N-phenylamino) biphenyl (TPD), 4,4'-bis (N- (1-naphthyl) -N-phenylamino) biphenyl (NPD) , 4,4'-bis (N, N-bis (4-biphenylyl) amino) biphenyl (TBDB), bis (N, N'-diphenyl-4-aminophenyl) -N, N-diphenyl-4,4' Benzidine derivatives such as -diamino-1,1'-biphenyl (TPD232);
4,4', 4 "-tris (3-methylphenyl (phenyl) amino) triphenylamine (m-MTDATA), 4,4', 4" -tris (1-naphthyl (phenyl) amino) triphenylamine ( A group of materials called starburst arylamines such as 1-TNATA);
Materials with a carbazole skeleton, especially carbazole multimers, specifically carbazole dimer derivatives such as bis (N-arylcarbazole) or bis (N-alkylcarbazole), carbazole trimeric derivatives, carbazole tetramers Derivatives of
Triphenylene compounds, stilbene compounds, hydrazone compounds;
Heterocyclic compounds such as pyrazoline derivatives, benzofuran derivatives, thiophene derivatives, oxadiazole derivatives, phthalocyanine derivatives, porphyrin derivatives;
Fullerene derivative;
Polymers such as polycarbonate and styrene derivatives, polythiophene, polyaniline, polyfluorene, polyvinylcarbazole and polysilane having a compound selected from the above compound group in the side chain;
Etc. are preferable.

Inorganic compounds such as p-type Si and p-type SiC can also be used as hole transport materials.

Further, the compound represented by the general formula (1) can also be used as a hole transport material because it has excellent electrochemical stability.

(Hole injection layer)
A hole injection layer may be provided between the anode and the hole transport layer. By providing the hole injection layer, the light emitting element can be driven at a lower voltage, and the durable life is also improved. For the hole injection layer, a material having a smaller ionization potential than the material usually used for the hole transport layer is preferably used. Specific examples thereof include a benzidine derivative such as TPD232, a starburst arylamine material group, and a phthalocyanine derivative.

It is also preferable that the hole injection layer is composed of the acceptor compound alone, or the acceptor compound is doped with another hole injection material. Examples of acceptor compounds include metal chlorides such as iron (III) chloride, aluminum chloride, gallium chloride, indium chloride and antimony chloride, metal oxides such as molybdenum oxide, vanadium oxide, tungsten oxide and ruthenium oxide. Charge transfer complexes such as tris (4-bromophenyl) aminium hexachloroantimonate (TBPAH) can be mentioned. In addition, organic compounds having a nitro group, a cyano group, a halogen atom or a trifluoromethyl group in the molecule, quinone compounds, acid anhydride compounds, fullerene and the like can also be mentioned.

Specific examples of these compounds, hexacyanobutadiene, hexacyano benzene, tetracyanoethylene, tetracyanoquinodimethane (TCNQ), tetrafluoro-tetracyanoquinodimethane _(F 4 -TCNQ), 2,3,6, 7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HAT-CN ₆ ), p-fluoranyl, p-chloranyl, p-bromanyl, p-benzoquinone, 2,6- Dichlorobenzoquinone, 2,5-dichlorobenzoquinone, tetramethylbenzoquinone, 1,2,4,5-tetracyanobenzene, o-dicyanobenzene, p-dicyanobenzene, 1,4-dicyano-2,3,5,6- Tetrafluorobenzene, 2,3-dichloro-5,6-dicyanobenzoquinone, o-dinitrobenzene, m-dinitrobenzene, p-dinitrobenzene, o-cyanonitrobenzene, m-cyanonitrobenzene, p-cyanonitrobenzene, 1,4 -Naftquinone, 2,3-dichloro-1,4-naphthoquinone, 1-nitronaphthalene, 2-nitronaphthalene, 1,3-dinitronaphthalene, 1,5-dinitronaphthalene, 9-cyanoanthracene, 9-nitroanthracene, 9 , 10-Anthracene, 1,3,6,8-tetranitrocarbazole, 2,4,7-trinitro-9-fluorenone, 2,3,5,6-tetracyanopyridine, maleic anhydride, phthalic anhydride , C ₆₀ , and C _{70 and the} like.

The hole injection layer may be a single layer regardless of whether the hole injection layer is composed of the acceptor compound alone or the hole injection material is doped with the acceptor compound. A plurality of layers may be laminated. The hole injection material used in combination when the acceptor compound is doped is the same compound as the compound used for the hole transport layer from the viewpoint that the hole injection barrier to the hole transport layer can be relaxed. More preferably.

(Light emitting layer)
The light emitting layer may be either a single layer or a plurality of layers, and each is formed of a light emitting material (host material, dopant material). The light emitting layer may be a mixture of the host material and the dopant material, or may be the host material alone. That is, in the organic thin film light emitting device according to the embodiment of the present invention, only the host material or the dopant material may emit light in each light emitting layer, or both the host material and the dopant material may emit light. From the viewpoint of efficiently utilizing electric energy and obtaining light emission with high color purity, the light emitting layer is preferably composed of a mixture of a host material and a dopant material.

Further, the host material and the dopant material may be either one type or a plurality of combinations. The dopant material may be contained entirely or partially in the host material. The dopant material may be laminated or dispersed. The emission color of the light emitting element can be controlled by the type of dopant material. If the amount of the dopant material is too large, a concentration quenching phenomenon occurs. Therefore, it is preferably used in an amount of 20% by weight or less, more preferably 10% by weight or less, based on the host material. The doping method may be a co-evaporation method with the host material, or may be mixed with the host material in advance and then vapor-deposited at the same time.

The luminescent material is not particularly limited, but specifically, metal chelating such as a fused ring derivative such as anthracene or pyrene, which has been known as a luminescent material, and tris (8-quinolinolate) aluminum (III). Oxynoid compounds; bisstyryl derivatives such as bisstyrylanthracene derivatives and distyrylbenzene derivatives; tetraphenylbutadiene derivatives, inden derivatives, coumarin derivatives, oxaziazole derivatives, pyrolopyridine derivatives, perinone derivatives, cyclopentadiene derivatives, oxadiazole derivatives, thio Asian zolopyridine derivatives, dibenzofuran derivatives, carbazole derivatives, indolocarbazole derivatives; polymers such as polyphenylene vinylene derivatives, polyparaphenylene derivatives, and polythiophene derivatives can be used.

The host material is not particularly limited, but is a compound having a fused aryl ring such as naphthalene, anthracene, phenanthrene, pyrene, chrysene, naphthacene, triphenylene, perylene, fluorene, fluorene, and inden, and derivatives thereof; N, N'-dinaphthyl-. Aromatic amine derivatives such as N, N'-diphenyl-4,4'-diphenyl-1,1'-diamine; metal chelated oxynoid compounds such as tris (8-quinolinolate) aluminum (III); distyrylbenzene Bistylyl derivatives such as derivatives; tetraphenylbutadiene derivatives, inden derivatives, coumarin derivatives, oxadiazole derivatives, pyrolopyridine derivatives, perylene derivatives, cyclopentadiene derivatives, pyrolopyrrole derivatives, thiadiazolopyridine derivatives, dibenzofuran derivatives, carbazole derivatives, India Locarbazole derivative, triazine derivative; polyphenylene vinylene derivative, polyparaphenylene derivative, polyfluorene derivative, polyvinylcarbazole derivative, polythiophene derivative and the like can be used.

When the compound represented by the general formula (1) is used as the electron transport material, the energy level of LUMO is close to that of the compound represented by the general formula (1), and electron injection is likely to occur. From this point of view, a compound having an anthracene skeleton is more preferable.

The dopant material in this case is a compound having a fused aryl ring such as naphthalene, anthracene, phenanthrene, pyrene, chrysen, triphenylene, perylene, fluorantene, fluorene, and inden, or a derivative thereof (for example, 2- (benzothiazole-2-yl)). ) -9,10-diphenylanthracene, 5,6,11,12-tetraphenylnaphthacene, etc.); furan, pyrrol, thiophene, silol, 9-silafluorene, 9,9'-spirobisilafluorene, benzothiophene, Compounds and derivatives having a heteroaryl ring such as benzofuran, indol, dibenzothiophene, dibenzofuran, imidazolepyridine, phenanthroline, pyridine, pyrazine, naphthylidine, quinoxaline, pyrolopyridine, thioxanthene; borane derivatives, distyrylbenzene derivatives; 4,4 Aminostyryl derivatives such as'-bis (2- (4-diphenylaminophenyl) ethenyl) biphenyl, 4,4'-bis (N- (stilben-4-yl) -N-phenylamino) stilben; aromatic acetylene derivatives , Tetraphenylbutadiene derivative, stillben derivative, aldazine derivative, pyromethene derivative, diketopyrrolo [3,4-c] pyrrole derivative; 2,3,5,6-1H, 4H-tetrahydro-9- (2'-benzothiazolyl) quinolidino [ 9,9a, 1-gh] cumarin derivatives such as coumarin; azole derivatives such as imidazole, thiazole, thiadiazol, carbazole, oxazole, oxadiazole, triazole and their metal complexes; and N, N'-diphenyl-N, N' Aromatic amine derivatives typified by −di (3-methylphenyl) -4,4′-diphenyl-1,1′-diamine; and the like can be used, but are not particularly limited.

Further, the light emitting layer may contain a phosphorescent material. The phosphorescent material is a material that exhibits phosphorescence even at room temperature. The phosphorescent material is not particularly limited, but is limited to iridium (Ir), ruthenium (Ru), rhodium (Rh), palladium (Pd), platinum (Pt), osmium (Os), and renium (Re). It is preferably an organic metal complex compound containing at least one metal selected from the group consisting of. Above all, an organometallic complex having iridium or platinum is more preferable from the viewpoint of having a high phosphorescence yield even at room temperature.

Host materials used in combination with phosphorescent dopant materials include, for example, indol derivatives, carbazole derivatives, indolocarbazole derivatives; nitrogen-containing aromatic compound derivatives having a pyridine, pyrimidine or triazine skeleton; polyarylbenzene derivatives, spiro Examples thereof include aromatic hydrocarbon compound derivatives such as fluorene derivatives, tolucene derivatives and triphenylene derivatives; compounds containing chalcogen elements such as dibenzofuran derivatives and dibenzothiophene derivatives; and organic metal complexes such as beryllium quinolinol complexes. However, the host material is not limited to these as long as it has a triplet energy larger than that of the dopant material used and electrons and holes are smoothly injected and transported from the respective transport layers.

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

Since the compound represented by the general formula (1) has high light emitting performance, it can also be used as a light emitting material. Since the compound represented by the general formula (1) exhibits strong light emission in the blue to green region (400 to 600 nm region), it can be suitably used as a blue and green light emitting material. Since the compound represented by the general formula (1) has a high fluorescence quantum yield, it is suitably used as a fluorescence dopant material. Further, the carbazole skeleton and the quinazoline skeleton have a high triplet excitation energy level, and the compound represented by the general formula (1) can be suitably used as a phosphorescent host material. In particular, it can be suitably used for a green phosphorescent host material and a red phosphorescent host material.

The preferred phosphorescent host or dopant is not particularly limited, and specific examples thereof include the following.

Further, the light emitting layer may contain a thermally activated delayed fluorescent material. Thermally activated delayed fluorescent material is also commonly referred to as TADF material. The thermally activated delayed fluorescent material promotes the inverse intersystem crossing from the triplet excited state to the singlet excited state by reducing the energy gap between the singlet excited state energy level and the triplet excited state energy level. However, it is a material with an improved probability of singlet excitation. The thermally activated delayed fluorescent material may be a single material exhibiting thermal activated delayed fluorescence, or a plurality of materials exhibiting thermal activated delayed fluorescence. When the material is composed of a plurality of materials, it may be used as a mixture, or layers made of each material may be laminated and used. As the thermal activated delayed fluorescent material, a known material can be used. Specific examples thereof include, but are not limited to, benzonitrile derivatives, triazine derivatives, disulfoxide derivatives, carbazole derivatives, indolocarbazole derivatives, dihydrophenazine derivatives, thiazole derivatives, oxadiazole derivatives and the like. No.

(Electronic transport layer)
The electron transport layer is a layer between the cathode and the light emitting layer. The electron transport layer may be a single layer or a plurality of layers, and may or may not be in contact with the cathode or the light emitting layer. It is preferable that the electron transport layer is composed of two or more layers, and the compound represented by the general formula (1) is contained on the side in contact with the light emitting layer. Further, as described above, the compound represented by the general formula (1) easily receives electrons from a compound having a pyrene skeleton, a phenanthroline skeleton, or a fluoranthene skeleton. It preferably contains a compound having a phenanthroline skeleton, a pyrene skeleton, or a fluoranthene skeleton.

It is desired that the electron transport layer has high electron injection efficiency from the cathode, efficiently transports the injected electrons, and has high electron injection efficiency into the light emitting layer. Therefore, the material constituting the electron transport layer is preferably a material having a large electron affinity, a large electron mobility, and excellent stability. Further, it is preferable that impurities that become traps are less likely to be generated during the production and use of such a material.

On the other hand, the electron transport layer plays a role of efficiently blocking the holes flowing from the anode from flowing to the cathode side when they enter the electron transport layer without recombination with the electrons in the light emitting layer. It is also preferable. In this case, even if the electron transport layer is made of a material having a low electron transport capacity, the effect of improving the luminous efficiency of the light emitting element is the same as when the electron transport layer is made of a material having a high electron transport capacity. Equivalent. Therefore, the electron transport layer in the present invention also includes a hole blocking layer capable of efficiently blocking the movement of holes as a synonym.

The electron transport material used for the electron transport layer is not particularly limited, and is represented by, for example, condensed polycyclic aromatic hydrocarbon derivatives such as naphthalene and anthracene, and 4,4'-bis (diphenylethenyl) biphenyl. Styryl aromatic ring derivatives, quinone derivatives such as anthracene and diphenoquinone, phosphoroxide derivatives, quinolinol complexes such as tris (8-quinolinolate) aluminum (III), benzoquinolinol complexes, hydroxyazole complexes, azomethine complexes, tropolone metal complexes and flavonols. Examples thereof include various metal complexes such as metal complexes. Since the driving voltage of the light emitting element is reduced and high luminous efficiency can be obtained, the electron transport material is composed of elements selected from carbon, hydrogen, nitrogen, oxygen, silicon, and phosphorus, and electron-accepting nitrogen is used. It is preferable to use a compound having a heteroaryl ring structure containing the mixture.

Examples of the aromatic heterocycle containing electron-accepting nitrogen include a pyridine ring, a pyrazine ring, a pyrimidine ring, a quinoline ring, a quinoxaline ring, a naphthylidine ring, a pyrimidopyrimidine ring, a benzoquinoline ring, a phenanthroline ring, an imidazole ring, and an oxazole ring. , Oxazole ring, triazole ring, thiazole ring, thiaziazole ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, phenanthleumidazole ring and the like.

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

The preferred electron transport material is not particularly limited, and specific examples thereof include the following.

In addition to these, International Publication No. 2004/63159, International Publication No. 2003/60956, "Applied Physics Letters", (USA), 1999, Vol. 74, No. 6, p. 856-867, "Organic Electronics", (Rankoku), 2003, Vol. 4, No. 2-3, p. Electron transport materials disclosed in 113-121, International Publication No. 2010/113743, International Publication No. 2010/1817, etc. can also be used.

Further, the compound represented by the general formula (1) can also be used as an electron transport material because it has a high electron injection transport ability. When the compound represented by the general formula (1) is used, it is not necessary to limit the compound to only one of them, and a plurality of kinds of the compounds represented by the general formula (1) may be mixed and used. One or more of the other electron transporting materials such as, and the compound represented by the general formula (1) may be mixed and used.

The electron transport layer may contain a donor material in addition to the electron transport material. Here, the donor material is a compound that facilitates electron injection from the cathode or the electron injection layer into the electron transport layer by improving the electron injection barrier, and further improves the electrical conductivity of the electron transport layer.

Preferred examples of the donor material in the present invention are an alkali metal, an inorganic salt containing an alkali metal, a complex of an alkali metal and an organic substance, an alkaline earth metal, an inorganic salt containing an alkaline earth metal, or an alkaline earth metal. Examples include a complex of and an organic substance. Preferred types of alkali metals and alkaline earth metals include alkali metals such as lithium, sodium and cesium, which have a low work function and a large effect of improving electron transport ability, and alkaline earth metals such as magnesium and calcium.

Further, since vapor deposition in vacuum is easy and handling is excellent, it is preferable that the metal is an inorganic salt or a complex of a metal and an organic substance rather than a simple substance. Further, a complex of a metal and an organic substance is more preferable in terms of easy handling in the atmosphere and easy control of the addition concentration. Examples of inorganic salts, LiO, _Li oxide such as 2 O, nitrides, LiF, NaF, fluorides KF, _{etc., Li 2 CO 3, Na 2} CO 3, K 2 CO 3, Rb 2 CO 3, Examples thereof include carbonates such as _{Cs 2} CO _{3 and the like.} In addition, preferred examples of alkali metals or alkaline earth metals include lithium because the raw materials are inexpensive and easy to synthesize. In addition, preferable examples of the organic substance in the complex of the metal and the organic substance include quinolinol, benzoquinolinol, flavonol, hydroxyimidazolipyridine, hydroxybenzazole, hydroxytriazole and the like. 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 quinolinol is particularly preferable. Two or more of these donor materials may be mixed and used.

The suitable doping concentration varies depending on the material and the film thickness of the doping region. For example, when the donor material is an inorganic material such as an alkali metal or an alkaline earth metal, the vapor deposition rate ratio of the electron transport material and the donor material is set to electron. Transport material: It is preferable that the donor material is co-deposited in the range of 10000: 1 to 2: 1 to form an electron transport layer. The vapor deposition rate ratio is more preferably 100: 1 to 5: 1, and even more preferably 100: 1 to 10: 1. When the donor material is a complex of a metal and an organic substance, the vapor deposition rate ratio of the electron transport material and the donor material should be in the range of electron transport material: donor material = 100: 1 to 1: 100. It is preferable that the layer is co-deposited to form an electron transport layer. The vapor deposition rate ratio is more preferably 10: 1 to 1:10, and even more preferably 7: 3 to 3: 7.

Further, the electron transport layer in which the compound represented by the general formula (1) is doped with a donor material may be used as a charge generation layer in a tandem type light emitting device that connects a plurality of light emitting devices. In particular, when an alkali metal or alkaline earth metal is doped as a donor material, the layer can be suitably used as a charge generation layer.

(Electron injection layer)
An electron injection layer may be provided between the cathode and the electron transport layer. Generally, the electron injection layer is inserted for the purpose of assisting the injection of electrons from the cathode into the electron transport layer. As the electron injection layer, a compound having a heteroaryl ring structure containing electron-accepting nitrogen may be used, or a layer containing the above-mentioned donor material may be used. The compound represented by the general formula (1) may be contained in the electron injection layer. Further, an insulator or a semiconductor inorganic substance can be used for the electron injection layer. By using these materials, it is possible to effectively prevent a short circuit of the light emitting element and improve the electron injection property, which is preferable.

As such an insulator, at least one metal compound selected from the group consisting of alkali metal chalcogenide, alkaline earth metal chalcogenide, alkali metal halide and alkaline earth metal halide is used. preferable.

It is more preferable to use a complex of an organic substance and a metal, which is a donor material, for the electron injection layer because the film thickness can be easily adjusted. Preferred examples of organic substances in such complexes include quinolinol, benzoquinolinol, pyridylphenol, flavonols, hydroxyimidazolipyridine, hydroxybenzazole, hydroxytriazole and the like. 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 quinolinol is particularly preferable.

The method for forming each of the above layers constituting the light emitting element is not particularly limited, such as resistance heating vapor deposition, electron beam deposition, sputtering, molecular lamination method, and coating method, but resistance heating vapor deposition or electron beam deposition is usually performed from the viewpoint of element characteristics. preferable.

The thickness of the organic layer is not limited because it depends on the resistance value of the luminescent substance, but it is preferably 1 to 1000 nm. The film thicknesses of the light emitting layer, the electron transport layer, and the hole transport layer are 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 device according to the embodiment of the present invention has a function of converting electric energy into light. Here, as the electric energy, a direct current is mainly used, but a pulse current or an alternating current can also be used. The current value and the voltage value are not particularly limited, but in consideration of the power consumption and the life of the element, it is preferable that the current value and the voltage value are selected so as to obtain the maximum brightness with the lowest possible energy.

The organic thin film light emitting device according to the embodiment of the present invention is suitably used as a display device such as a display that displays in a matrix and / or segment system, for example.

The matrix method is a method in which pixels for display are arranged two-dimensionally such as in a grid pattern or a mosaic pattern, and characters and images are displayed as a set of pixels. The shape and size of the pixels are determined by the application. For example, for displaying images and characters on a personal computer, monitor, or television, rectangular pixels with a side of 300 μm or less are usually used, and in the case of a large display such as a display panel, pixels with a side on the order of mm should be used. become. In the case of monochrome display, pixels of the same color may be arranged, but in the case of color display, red, green, and blue pixels are displayed side by side. In this case, there are typically a delta type and a stripe type. The drive method of this matrix may be either a line sequential drive method or an active matrix. Although the structure of the line sequential drive is simple, the active matrix may be superior in consideration of the operating characteristics, so it is preferable to use the active matrix properly depending on the application.

The segment method is a method in which a pattern is formed so as to display predetermined information, and a region determined by the arrangement of the pattern is made to emit light. Examples of the display using the segment method include a time and temperature display in a digital clock and a thermometer, an operating state display of an audio device and an electromagnetic cooker, and a panel display of an automobile. The matrix method and the segment method may coexist in the same panel.

The organic thin film light emitting device according to the embodiment of the present invention is also preferably used as a backlight for various devices and the like. The backlight is mainly used for the purpose of improving the visibility of a display device that does not emit light by itself, and is used for a liquid crystal display device, a clock, an audio device, an automobile panel, a display board, a sign, and the like. In particular, the organic thin film light emitting element of the present invention is preferably used for a liquid crystal display device, especially a backlight for a personal computer for which thinning is being studied, and it is possible to provide a backlight thinner and lighter than the conventional one.

The organic thin film light emitting device according to the embodiment of the present invention is also preferably used as a lighting device for organic EL lighting and the like. Organic EL lighting is used for general lighting, exhibition lighting, tail lamps of automobiles, and the like, and the organic thin film light emitting element of the present invention is preferably used for these.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples. In addition, Examples 14 and 15 shall be read as Reference Examples 1 and 2.

Synthesis example 1
Synthesis of intermediate [A]

In a 500 mL three-necked flask, 9.90 g (50.0 mmol) of 2,4-dichloroquinazoline, 15.1 g (52.5 mmol) of 9-phenylcarbazole-3-boronic acid, 250 mL of 1,2-dimethoxyethane, 2M carbonate. 38 mL (75 mmol) of an aqueous sodium solution was added, and the inside of the container was replaced with nitrogen. To this mixed solution, 0.351 g (0.500 mmol) of bis (triphenylphosphine) palladium (II) dichloride was added, and the mixture was heated under reflux 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]

2.03 g (5.00 mmol) of intermediate [A], 1.51 g (5.25 mmol) of 4- (9H-carbazole-9-yl) phenylboronic acid, 50 mL of 1,4-dioxane in a 100 mL three-necked flask. 3.8 mL (7.5 mmol) of a 2M tripotassium phosphate aqueous solution was added, and the inside of the container was replaced with nitrogen. To this mixture, 0.046 g (0.050 mmol) of tris (dibenzylideneacetone) dipalladium (0) and 0.028 g (0.10 mmol) of tricyclohexylphosphine were added, and the mixture was heated under reflux in an oil bath at 110 ° C. for 4 hours. I let you. After completion of the reaction, the mixture 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, the purified product was dissolved by heating in 40 mL of butyl acetate, cooled, recrystallized, collected by filtration, and vacuum dried to obtain 2.36 g of a yellowish white solid of compound [1].

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

Compound [1] was used as a light emitting element material after being sublimated and purified 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 500 mL three-necked flask, 5.94 g (30. mmol) of 2,4-dichloroquinazoline, 5.15 g (33.0 mmol) of 4-chlorophenylboronic acid, 150 mL of 1,2-dimethoxyethane, and 23 mL of a 2M sodium carbonate aqueous solution ( 45 mmol) was added, and the inside of the container was replaced with nitrogen. To this mixture was added 0.211 g (0.300 mmol) of bis (triphenylphosphine) palladium (II) dichloride, and the mixture was heated under reflux 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 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]

In a 300 mL three-necked flask, 4.11 g (15.0 mmol) of the intermediate [B], 4.73 g (16.5 mmol) of 9-phenylcarbazole-3-boronic acid, 150 mL of 1,2-dimethoxyethane, 2M phosphate. 11 mL (22.5 mmol) of a tripotassium aqueous solution was added, and the inside of the container was replaced with nitrogen. To this mixture was added 0.105 g (0.150 mmol) of bis (triphenylphosphine) palladium (II) dichloride, and the mixture was heated under reflux in an oil bath at 90 ° C. for 7 hours. After completion of the reaction, the mixture 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]

2.40 g (5.00 mmol) of intermediate [C], 0.918 g (7.50 mmol) of carbazole, 0.721 g (7.50 mmol) of tert-butoxysodium are placed in a 100 mL three-necked flask, and 50 mL of o-xylene is placed. Was added, and the inside of the container was replaced with nitrogen. To this mixture, 0.046 g (0.050 mmol) of tris (dibenzylideneacetone) dipalladium (0) and 0.028 g (0.10 mmol) of tricyclohexylphosphine were added, and the mixture was heated under reflux in an oil bath at 150 ° C. for 3 hours. bottom. After completion of the reaction, the mixture 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. Further, the purified product was dissolved by heating in 40 mL of butyl acetate, cooled, recrystallized, collected by filtration, and vacuum dried to obtain 2.39 g of a yellowish white solid of compound [2].

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

Compound [2] was used as a light emitting element material after being sublimated and purified at about 330 ° C. under a pressure of ^{1 × 10 -3 Pa using an oil diffusion pump.}

Synthesis example 3
Synthesis of intermediate [E]

Intermediate E was synthesized by applying the method described in International Publication No. 2006/049013. That is, 2.43 g of magnesium was placed in a 500 mL three-necked flask, 10 mL of dry tetrahydrofuran was added, and the inside of the container was replaced with nitrogen. A solution of 32.2 g (100 mmol) of 9- (4-bromophenyl) carbazole in 200 mL of dry tetrahydrofuran was added dropwise to the flask to prepare a Grignard reagent. A solution of 7.63 g (50 mmol) of 2-amino-5-chlorobenzonitrile in 50 mL of dry tetrahydrofuran was added dropwise thereto over 30 minutes. After refluxing for another 1.5 hours, the mixture was cooled to 0 ° C. in an ice-water bath. Then, a solution of 13.2 g (60 mmol) of 4-bromobenzoyl chloride in 100 mL of dry tetrahydrofuran was added dropwise over 10 minutes, and the mixture was heated under reflux in an oil bath at 60 ° C. for 2 hours. After completion of the reaction, the mixture was cooled to 0 ° C. in 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]

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, 2M phosphate in a 300 mL three-necked flask. 7.5 mL (15.0 mmol) of the tripotassium aqueous solution was added, and the inside of the container was replaced with nitrogen. To this mixture was added 0.070 g (0.10 mmol) of bis (triphenylphosphine) palladium (II) dichloride, and the mixture was heated under reflux in an oil bath at 90 ° C. for 7 hours. After completion of the reaction, the mixture 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 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 the intermediate [F], 0.641 g (5.25 mmol) of phenylboronic acid, 50 mL of 1,4-dioxane, and 3.8 mL of a 2M tripotassium phosphate aqueous solution ( 7.5 mmol) was added, and the inside of the container was replaced with nitrogen. To this mixture, 0.046 g (0.050 mmol) of tris (dibenzylideneacetone) dipalladium (0) and 0.028 g (0.10 mmol) of tricyclohexylphosphine were added, and the mixture was heated back in an oil bath at 110 ° C. for 4 hours. I let you. 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 vacuum dried to obtain 3.28 g of a yellowish white solid of compound [3].

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

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

The compounds [4] to [41] used in the following examples can also be synthesized and purified from the corresponding raw materials by using a method similar to the methods described in Synthesis Examples 1 to 3.

Example 1
A glass substrate (manufactured by Geomatec Co., Ltd., 11Ω / □, sputtered product) on which an ITO transparent conductive film was deposited at 165 nm was cut into a size of 38 × 46 mm and etched. The obtained substrate was ultrasonically cleaned with "Semicoclean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then washed with ultrapure water. This substrate was subjected to UV-ozone treatment for 1 hour immediately before the production of the light emitting element, installed 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, HAT-CN ₆ was first vapor-deposited at 5 nm as a hole injection layer, and then HT-1 was vapor-deposited at 50 nm as a hole transport layer. Next, as a light emitting layer, 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. Next, as an electron transport layer, compound [1] was deposited to a thickness of 35 nm. Next, after lithium fluoride was vapor-deposited at 0.5 nm, aluminum was vapor-deposited at 1000 nm to serve as a cathode, and a 5 × 5 mm square light emitting device was produced. The film thickness referred to here is a crystal oscillation type film thickness monitor display value, and is common to other examples and comparative examples. The characteristics when this light emitting element was lit at a brightness of 1000 cd / m ² were a drive voltage of 4.11 V and an external quantum efficiency of 5.63%. When the initial brightness was set to 1000 cd / m ² and the product was driven with a constant current, the time (durability) for the brightness to decrease by 20% was 1020 hours. Compound [1], HAT-CN ₆ , HT-1, H-1, and D-1 are the compounds shown below.

Examples 2-32
A light emitting device was produced and evaluated in the same manner as in Example 1 except that the compounds shown in Table 1 were used for the electron transport layer. The results are shown in Table 1. Compounds [2] to [32] are the compounds shown below.

Comparative Examples 1-12
A light emitting device was produced and evaluated in the same manner as in Example 1 except that the compounds shown in Table 1 were used for the electron transport layer. The results are shown in Table 1. 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 an ITO transparent conductive film was deposited at 165 nm was cut into a size of 38 × 46 mm and etched. The obtained substrate was ultrasonically cleaned with "Semicoclean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then washed with ultrapure water. This substrate was subjected to UV-ozone treatment for 1 hour immediately before the production of the light emitting element, installed 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, HAT-CN ₆ was first vapor-deposited at 5 nm as a hole injection layer, and then HT-1 was vapor-deposited at 40 nm as a hole transport layer. Next, HT-2 was vapor-deposited at 10 nm as a hole transport layer for blue. Next, as a light emitting layer, 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. Next, as the first electron transport layer, compound [1] was deposited to a thickness of 25 nm. Further, as the second electron transport layer, compound E-13 is used as the electron transport material and 2E-1 is used as the donor material, and the vapor deposition rate ratio of E-13 and 2E-1 is E-13: 2E-1 = 1. It was laminated to a thickness of 10 nm so as to be 1: 1. Next, after lithium fluoride was vapor-deposited at 0.5 nm, aluminum was vapor-deposited at 1000 nm to serve as a cathode, and a 5 × 5 mm square light emitting device was produced. The characteristics when this light emitting element was lit at a brightness of 1000 cd / m ² were a drive voltage of 3.97 V and an external quantum efficiency of 6.30%. When the initial brightness was set to 1000 cd / m ² and driven with a constant current, the time for the brightness to decrease by 20% was 1710 hours. HT-2, E-13, and 2E-1 are the compounds shown below.

Examples 34-50
A light emitting device was produced and evaluated in the same manner as in Example 33, except that the compounds shown in Table 2 were used for the host material and the first electron transport layer, respectively. The results are shown in Table 2. H-2 and H-3 are the compounds shown below.

Comparative Examples 13-48
A light emitting device was produced and evaluated in the same manner as in Example 21 except that the compounds shown in Table 2 were used for the host material and the first electron transport layer. The results are shown in Table 2.

Example 51
A glass substrate (manufactured by Geomatec Co., Ltd., 11Ω / □, sputtered product) on which an ITO transparent conductive film was deposited at 165 nm was cut into a size of 38 × 46 mm and etched. The obtained substrate was ultrasonically cleaned with "Semicoclean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then washed with ultrapure water. This substrate was subjected to UV-ozone treatment for 1 hour immediately before the production of the light emitting element, installed 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, HAT-CN ₆ was first vapor-deposited at 5 nm as a hole injection layer, and then HT-1 was vapor-deposited at 40 nm as a hole transport layer. Next, HT-2 was vapor-deposited at 10 nm as a hole transport layer for blue. Next, as a light emitting layer, 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. Next, as the first electron transport layer, compound [1] was deposited to a thickness of 25 nm. Further, as the second electron transport layer, compound E-14 is used as the electron transport material and 2E-1 is used as the donor material, and the vapor deposition rate ratio of E-14 and 2E-1 is E-14: 2E-1 = 1. It was laminated to a thickness of 10 nm so as to be 1: 1. Next, after lithium fluoride was vapor-deposited at 0.5 nm, aluminum was vapor-deposited at 1000 nm to serve as a cathode, and a 5 × 5 mm square device was manufactured. The characteristics when this light emitting element was lit at a brightness of 1000 cd / m ² were a drive voltage of 4.21 V and an external quantum efficiency of 7.52%. When the initial brightness was set to 1000 cd / m ² and driven with a constant current, the time for the brightness to decrease by 20% was 2050 hours. E-14 is a compound shown below.

Examples 52-68
A light emitting device was produced and evaluated in the same manner as in Example 51, except that the compounds shown 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 the compounds shown below.

Comparative Examples 49-84
A light emitting device was produced and evaluated in the same manner as in Example 51, except that the compounds shown 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 an ITO transparent conductive film was deposited at 90 nm was cut into a size of 38 × 46 mm and etched. The obtained substrate was ultrasonically cleaned with "Semicoclean 56" (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then washed with ultrapure water. This substrate was subjected to UV-ozone treatment for 1 hour immediately before the device was manufactured, placed in a vacuum vapor deposition apparatus, and evacuated ^{until the degree of vacuum in the apparatus became 5 × 10 -4} Pa or less. _{HAT-CN 6} was deposited at 10 nm as a hole injection layer by a resistance heating method. Next, HT-1 was deposited at 110 nm as the first hole transport layer. Next, compound HT-2 was deposited at 20 nm as a second hole transport layer. Next, as the light emitting layer, 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. Next, as the first electron transport layer, compound [1] was deposited to a thickness of 25 nm. Further, as the second electron transport layer, compound E-14 is used as the electron transport material and compound 2E-1 is used as the donor material, and the vapor deposition rate ratio of E-14 and 2E-1 is E-14: 2E-1 =. It was laminated to a thickness of 20 nm so as to have a ratio of 1: 1.

Next, after compound 2E-1 was vapor-deposited at 1 nm, a magnesium-silver co-deposited film was deposited at a vapor deposition rate ratio of magnesium: silver = 10: 1 (= 0.5 nm / s: 0.05 nm / s) at 60 nm. A 5 × 5 mm square element was manufactured as a cathode. The film thickness referred to here is a crystal oscillation type film thickness monitor display value. When this light emitting element was ^{driven by direct current at 10 mA / cm 2} , green light emission with a luminous efficiency of 45.3 m / W was obtained. ^{Regarding the effective efficiency (lm / W), the front luminance (cd / cm 2} ) obtained by the measurement of the spectral radiance meter (CS-1000, manufactured by Konica Minolta) and the power density (W / cm) applied to the element are used. ^It was calculated from 2) and the radiance angle (sr, steradian). When this light emitting element was ^{continuously driven by a direct current of 10 mA / cm 2} , the brightness was halved in 5430 hours. H-4 and D-2 are the compounds shown below.

Examples 70-74
A light emitting device was produced and evaluated in the same manner as in Example 69, except that the compounds shown in Table 4 were used for the first electron transport layer. The results are shown in Table 4.

Comparative Examples 85-96
A light emitting device was prepared and evaluated in the same manner as in Example 69, except that the compounds shown in Table 4 were used for the first electron transport layer. The results are shown in Table 4.

Claims (18)

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

(In formula (1), L ¹ is a single-bonded or substituted or unsubstituted arylene group. L ² is a substituted or unsubstituted arylene group. L ¹ is of X ^{2 to} X ⁴ and R ⁵⁵ . ^{L 2} is connected at any one of the positions, and L 2 is connected at any one of X ¹⁴ , X ¹⁵ and R ^56. However, L ¹ is connected at the position of ^{R 55 and L 2} is connected. Except when connecting at the position of R ^56.
R ⁵¹ to R ⁵⁴ are each independently, Ru hydrogen atom or an aryl group der.
R ⁵⁵ and ^{R 56} are, Ru A reel group der.
X ^{n (n} = 1~16), ^{respectively,} is C-R n (n = 1~16 ).
R ^{n (n} = 1~16) are each independently, Ru hydrogen atom or an amino group der. ) A compound represented by the following general formula (1).

(In formula (1), L ² is a single bond and L ¹ is a substituted or unsubstituted arylene group. L ¹ is linked at any one of X ² , X ³ and R ^55. L ² is connected at any one of X ¹⁴ , X ¹⁵ and R ^{56 , except when L 1} is connected at ^{R 55 and L 2} is ^{connected at R 56.} ..
R ⁵¹ to R ⁵⁴ are each independently, Ru hydrogen atom or an aryl group der.
R ⁵⁵ and ^{R 56} are, Ru A reel group der.
X ^{n (n} = 1~16), ^{respectively,} is C-R n (n = 1~16 ).
R ^{n (n} = 1~16) are each independently, Ru hydrogen atom or an amino group der. ) The compound according to claim 1 or 2, ^{wherein L 1} is ^{linked at the position of X 3 in} the general formula (1). The compound according to claim 1 or 3, ^{wherein L 1} is a single bond in the general formula (1). The compound according to any one of claims 1, 3 and 4 ^{, wherein L 2} is a substituted or unsubstituted phenylene group in the general formula (1). The compound according to any one of claims 1 to 5 ^{, wherein L 2} is ^{linked at the position of X 14 in} the general formula (1). The compound according to any one of claims 1, 3, 5, and 6, wherein ^{L 1} is a substituted or unsubstituted arylene group in the general formula (1). ^{The compound according to claim 7, wherein L 1} is a substituted or unsubstituted phenylene group in the general formula (1). In the general formula (1), when ^{any one of X n} (n = 1 to 16) is C-R ⁿ (n = 1 to 16), ^{all of the R n} are hydrogen atoms, claim 1 to 1. The compound according to any one of 8. An electronic device containing the compound according to any one of claims 1 to 9. The element according to any one of claims 1 to 9, which is an element having an anode, a cathode, and an organic layer interposed between the anode and the cathode, and emitting light by electric energy. An organic thin film light emitting device containing a compound. The organic thin film light emitting device according to claim 11, wherein the organic layer has at least a light emitting layer and an electron transporting layer, and the electron transporting layer contains the compound according to any one of claims 1 to 9. The organic thin film light emitting device according to claim 11 or 12, wherein the electron transport layer is composed of two or more layers, and the compound according to any one of claims 1 to 9 is contained on the side in contact with the light emitting layer. 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 device according to any one of claims 12 to 14, wherein the light emitting layer contains at least one compound having an anthracene skeleton. The organic thin film light emitting device according to any one of 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 device according to any one of claims 11 to 16. A lighting device comprising the organic thin film light emitting device according to any one of claims 11 to 16.