JP5087815B2 - Organic EL device - Google Patents

Description

The present invention relates to a highly efficient organic EL element.

  An organic electroluminescence device has a structure in which a light emitting layer containing a light emitting compound is sandwiched between a cathode and an anode, and emits light by injecting electrons and holes into the light emitting layer and recombining them. It is a light-emitting type, has a wide viewing angle, has high visibility, is a thin film and a completely solid element, and has attracted attention from the viewpoints of space saving and portability.

  For the development of organic electroluminescence elements for practical use in the future, organic electroluminescence elements that emit light efficiently and with high luminance with lower power consumption are desired. For example, in the technologies disclosed in Patent Document 1, Reference 2, Patent Document 3, and the like, light emission from an excited singlet is used, and the limit of the external extraction quantum efficiency (ηext) is 5%. The efficiency is low.

On the other hand, since Princeton University reported an organic electroluminescence device using phosphorescence emission from an excited triplet (see, for example, Non-Patent Document 1), research on materials that exhibit phosphorescence at room temperature (for example, non-patent) Reference 2 and Patent Reference 4) are active,
An organic EL device having high luminous efficiency using these as a dopant has been reported.

  The use of an excited triplet has a high internal quantum efficiency, so the light emission efficiency is in principle four times that of an excited singlet, and almost the same performance as a cold-cathode tube is obtained. There is a lot of attention.

As for the phosphorescent dopant, many compounds have been studied focusing on heavy metal complexes such as an iridium complex system. Tris (2-phenylpyridine) iridium (see, for example, Non-Patent Document 2), and L ₂ Ir ( acac) (wherein L is a bidentate ligand and acac represents acetylacetone), (ppy) ₂ Ir (acac) (see, for example, Non-Patent Document 3), and tris (2- (P-Tolyl) pyridine) iridium (Ir (ptpy) ₃ ), tris (benzo [h] quinoline) iridium (Ir (bzq) ₃ ), Ir (bzq) ₂ ClP (Bu) ₃ etc. , See Non-Patent Document 4.).

  In organic electroluminescence devices using phosphorescence emission from these excited triplets, the external extraction efficiency close to 20%, which is the theoretical limit, has been achieved in some cases, but there is a problem of a significant decrease in efficiency during high-luminance emission. Depending on the luminescent color, sufficient efficiency has not yet been obtained and improvements are required. Organic EL elements with high efficiency, low power consumption, and high brightness are desired, and for display and lighting applications. Therefore, there is a need for practical durability.

  This point has been studied from various directions so far. For example, in Patent Documents 5, 6, 7, 8, 9 and the like, a method of encapsulating a hygroscopic agent in the element has been studied and more durability has been studied. In order to construct an organic EL device having a high level of efficiency, studies have been repeated and there are a great many disclosures.

  In such an organic EL element, each layer constituting the organic EL element is generally formed by vacuum deposition.

  For example, an ordinary organic EL element is generally deposited at a deposition rate of 0.2 nm / s or less at the research stage by a vacuum deposition apparatus, and at a deposition rate of about 0.5 nm / s in manufacturing. .

  Conventionally, in the formation of the organic EL element light emitting layer by vacuum deposition, when the deposition rate is 0.2 nm / s or less (low-speed deposition) and the deposition rate is about 0.5 nm / s (high-speed deposition). It has been known that the performance of the organic EL element obtained by the high-speed vapor deposition is slightly worse or the same, and at least not good.

  In the present invention, when a functional layer of an organic EL element is formed by vacuum deposition using a compound having a specific structure as an organic EL material, the efficiency of the obtained organic EL element is improved by high-speed deposition. I found out. In particular, the improvement in the efficiency of the organic EL obtained at a deposition rate (film formation rate on the substrate) of 1 nm / s or more was remarkable. Moreover, the same effect was recognized also at the time of co-evaporation with the other component of an organic EL layer.

As described above, there have been too many attempts to obtain a highly efficient organic EL element by a manufacturing method such as adjustment of film formation speed by vacuum deposition of each layer constituting the organic EL element, particularly a light emitting layer and a hole blocking layer. It has not been.
Japanese Patent No. 3093796 Japanese Unexamined Patent Publication No. 63-264692 JP-A-3-255190 US Pat. No. 6,097,147 JP 2002-31559 A Japanese Patent Laid-Open No. 08-236271 JP 2002-367771 A Japanese Patent Application Laid-Open No. 07-065958 JP 2002-198170 A M.M. A. Baldo et al. , Nature, 395, 151-154 (1998) M.M. A. Baldo et al. , Nature, 403, 17, 750-753 (2000) M.M. E. Thompson et al. , The 10th International Works on Organic and Organic Electroluminescence (EL'00, Hamamatsu) Moon-Jae Youn. 0 g, Tsutsuo Tsutsui et al. , The 10th International Works on Organic and Organic Electroluminescence (EL'00, Hamamatsu)

The present invention is a high efficiency, i.e., high luminous efficiency, driving voltage is to obtain the organic EL element that can be lowered.

〔式中、Ｒ ₆₀₁ 〜Ｒ ₆₀₆ は、水素原子、もしくは下記一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基を表すが、Ｒ ₆₀₁ 〜Ｒ ₆₀₆ のうち二つ、または三つは該一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基を表す。但し、二つ、または三つの該一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基は隣接しない。〕

〔式中、Ｒ ₆₁₁ 〜Ｒ ₆₂₀ は、水素原子、アルキル基、アリール基、ハロゲン原子、隣接する基どうしが結合してベンゼン環を形成する基、もしくは下記一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基を表すが、Ｒ ₆₁₁ 〜Ｒ ₆₂₀ のうち二つ、または四つは該一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基を表す。但し、該一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基が二つの場合、Ｒ ₆₁₃ 及びＲ ₆₁₈ が該一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基を表し、該一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基が四つの場合、Ｒ ₆₁₂ 、Ｒ ₆₁₄ 、Ｒ ₆₁₇ 及びＲ ₆₁₉ が該一般式（１−３）、（１−５）、（１−６）、（１−９）または（１−１０）で表される基を表す。〕

〔式中、Ｒ ₅₂₂ 〜Ｒ₅₂₇は、各々独立に、水素原子、アルキル基またはアリール基を表す。〕

〔式中、Ｒ ₅₄₂ 〜Ｒ₅₄₈は、各々独立に、水素原子、アルキル基またはアリール基を表す。〕

〔式中、Ｒ ₅₅₂ 〜Ｒ₅₅₈は、各々独立に、水素原子、アルキル基またはアリール基を表す。〕

〔式中、Ｒは、水素原子、アルキル基またはアリール基を表す。また、複数のＲは、各々同一でもよく、異なっていてもよい。〕

〔式中、Ｒは、水素原子、アルキル基またはアリール基を表す。また、複数のＲは、各々同一でもよく、異なっていてもよい。〕
なお、以下（１）〜（１３）は参考とされる手段である。 The above object of the present invention is achieved by the following means 1 .
1. An organic EL device comprising a hole blocking layer formed by depositing at least one compound represented by the following general formula ( 3) or general formula (4) at a deposition rate of 0.5 nm / s or more .

[Wherein R _{601 to} R ₆₀₆ are each represented by a hydrogen atom, or the following general formula (1-3), (1-5), (1-6), (1-9) or (1-10) 2 or 3 of R _{601 to} R ₆₀₆ are the general formulas (1-3), (1-5), (1-6), (1-9) or (1- The group represented by 10) is represented. However, two or three groups represented by the general formula (1-3), (1-5), (1-6), (1-9) or (1-10) are not adjacent. ]

[Wherein R _{611 to} R ₆₂₀ represent a hydrogen atom, an alkyl group, an aryl group, a halogen atom, a group in which adjacent groups are bonded to form a benzene ring, or the following general formulas (1-3), (1 -5), (1-6), (1-9) or a group represented by (1-10), two or four of R _{611 to} R ₆₂₀ are represented by the general formula (1- 3) represents a group represented by (1-5), (1-6), (1-9) or (1-10). However, when there are two groups represented by formulas (1-3), (1-5), (1-6), (1-9) or (1-10), R ₆₁₃ and R ₆₁₈ are The group represented by the general formula (1-3), (1-5), (1-6), (1-9) or (1-10) is represented, and the general formula (1-3), ( 1-5), (1-6), (1-9) or (1-10), when there are four groups, R ₆₁₂ , R ₆₁₄ , R ₆₁₇ and R ₆₁₉ are represented by the general formula (1- 3) represents a group represented by (1-5), (1-6), (1-9) or (1-10). ]

[ Wherein, R _{522 to} R ₅₂₇ each independently represents a hydrogen atom, an alkyl group or an aryl group. ]

[ Wherein, R _{542 to} R ₅₄₈ each independently represents a hydrogen atom, an alkyl group or an aryl group. ]

[ Wherein, R _{552 to} R ₅₅₈ each independently represents a hydrogen atom, an alkyl group or an aryl group. ]

[ Wherein, R represents a hydrogen atom, an alkyl group or an aryl group. The plurality of R may be the same or different. ]

[ Wherein, R represents a hydrogen atom, an alkyl group or an aryl group. The plurality of R may be the same or different. ]
Your name, the following (1) to (13) is a means to be a reference.

(1 ) An organic EL device having a layer in which a compound represented by the following general formula (1) is deposited at a deposition rate of 0.5 nm / s or more.

[In the formula, Z ₁ represents an aromatic heterocyclic ring which may have a substituent, Z ₂ represents an aromatic heterocyclic ring or an aromatic hydrocarbon ring which may each have a substituent, Z ₃ represents a divalent linking group or a simple bond. R ₁₀₁ represents a hydrogen atom or a substituent. ]
(2 ) The organic EL device according to ( 1 ) , wherein the organic EL device has a layer in which the compound represented by the general formula (1) is deposited at a deposition rate of 1 nm / s or more.

(3 ) An organic EL device comprising a layer obtained by co-evaporating a compound represented by the following general formula (1) and a different organic EL material at a deposition rate of 0.5 nm / s or more.

[In the formula, Z ₁ represents an aromatic heterocyclic ring which may have a substituent, Z ₂ represents an aromatic heterocyclic ring or an aromatic hydrocarbon ring which may each have a substituent, Z ₃ represents a divalent linking group or a simple bond. R ₁₀₁ represents a hydrogen atom or a substituent. ]
(4) according to (3), characterized in that it has a layer formed by co-deposition by the general formula (1) and the compound represented by this different organic EL material combined 1 nm / s or more deposition rate Organic EL element.

(5 ) The organic EL device according to any one of ( 1 ) to ( 4 ) , wherein the compound represented by the general formula (1) is contained in the hole blocking layer.

(6 ) The organic EL device according to ( 3 ) or ( 4 ) , wherein the organic EL element is different from the compound represented by the general formula (1) co-deposited with the compound represented by the general formula (1). An organic EL device characterized in that the material is a phosphorescent compound.

(7 ) The organic EL device according to ( 3 ) or ( 4 ) , wherein the organic EL element is different from the compound represented by the general formula (1) co-deposited with the compound represented by the general formula (1). An organic EL element characterized in that the material is an alkali metal, an alkaline earth metal or a salt thereof.

(8 ) Illumination using the organic EL element according to any one of ( 1 ) to ( 7 ) .

(9 ) The display element using the organic EL element of any one of said ( 1 ) - ( 7 ) .

(10 ) A method for producing an organic EL device, comprising depositing a compound represented by the following general formula (1) at a deposition rate of 0.5 nm / s or more.

[In the formula, Z ₁ represents an aromatic heterocyclic ring which may have a substituent, Z ₂ represents an aromatic heterocyclic ring or an aromatic hydrocarbon ring which may each have a substituent, Z ₃ represents a divalent linking group or a simple bond. R ₁₀₁ represents a hydrogen atom or a substituent. ]
(11 ) A method for producing an organic EL device, wherein a compound represented by the following general formula (1) and a different organic EL material are co-deposited at a deposition rate of 0.5 nm / s or more.

[In the formula, Z ₁ represents an aromatic heterocyclic ring which may have a substituent, Z ₂ represents an aromatic heterocyclic ring or an aromatic hydrocarbon ring which may each have a substituent, Z ₃ represents a divalent linking group or a simple bond. R ₁₀₁ represents a hydrogen atom or a substituent. ]
(12 ) The method for producing an organic EL device according to ( 10 ) , wherein the compound represented by the general formula (1) is deposited at a deposition rate of 1 nm / s or more.

(13 ) A method for producing an organic EL device, wherein the compound represented by the general formula (1) and an organic EL material different from the compound are co-deposited at a deposition rate of 1 nm / s or more.

  According to the present invention, a highly efficient organic EL device can be obtained.

  The best mode for carrying out the present invention will be described below, but the present invention is not limited thereto.

  As a typical configuration example of the organic EL element, for example, from a relatively simple configuration including anode / light emitting layer / electron transport layer / cathode, etc., anode / hole transport layer / light emitting layer / electron transport. Layers / cathodes and the like, and various configurations including practical configurations such as anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode.

As an anode, for example, a metal such as Au, a metal such as CuI, indium tin oxide (ITO), a metal (4 eV or higher), an alloy, an electrically conductive compound, etc. An electron injection layer between electrodes of a potassium alloy, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, etc., a metal having a small work function (4 eV or less) (referred to as an electron injecting metal), an alloy, an electrically conductive compound, An injection layer such as a hole injection layer, a hole blocking layer, an electron blocking layer, and a light emitting layer are arranged in accordance with a predetermined configuration. A voltage is applied between the electrodes, and electrons and holes are respectively applied. To emit light.

  Each layer constituting these organic EL elements is generally formed by sputtering, vacuum vapor deposition, CVD (Chemical Vapor Deposition), etc. In particular, in the organic EL material, in the present invention, The organic compounds used in the above are called as follows, and it is a common and preferable method to form various films including these organic EL materials constituting the organic EL element by a vacuum deposition method.

  In the vacuum evaporation method, the sample (substrate) to be formed into a film and the raw material of the film are placed in a container, the whole is in a vacuum state, the raw material is melted with heat, and evaporated, the raw material becomes gas molecules and collides with the sample. , And a film is formed. Further, it may sublimate from a solid to a gas.

There are a resistance heating method, an electron beam method, a high frequency induction method, a laser method, and the like depending on the method of heating and dissolving the raw material compound. Since the vacuum is higher than sputtering (several Pa) (10 ⁻³ to 10 ⁻⁵ Pa), the source molecules do not collide with the remaining gas molecules before reaching the sample (substrate) on which the film is to be deposited. Since it does not collide with the sample, the film forming speed is high, the sample is not damaged by plasma such as sputtering, the structure of the apparatus is simple, the film thickness can be easily controlled with a shutter, and the purity is high in vacuum. It is suitable for forming an organic material thin film because it can be formed.

  The basic equipment consists of a vacuum vessel for vapor deposition (a bell-shaped vessel is called a bell jar), an exhaust device, a filament for heating a sample (some boats and quartz cells are also available), etc. .

  As an apparatus, for example, as a resistance heating type, manufactured by Sanyu Electronics Co., Ltd., SVC-700, SVC-700T / 700TA, SVC-700TM / 700-2, etc., and as an electron beam (EB) type, SVC-700EB / SVC -700 LEB and the like are commercially available.

Therefore, as a film forming method, the substrate is disposed in the vacuum vessel (deposition tank) of the vapor deposition apparatus which has been evacuated to about 10 ⁻⁴ Pa as described above by the exhaust device, and the vapor deposition raw material is also placed on the boat. A raw material (organic EL material) placed in a mounting container is heated with a filament to melt and vaporize the raw material, and deposit a vapor deposition raw material on the substrate to form a film.

  Therefore, in order to increase the deposition rate, the heating temperature of the raw material compound is usually increased to promote vaporization.

  In the present invention, when the compound represented by the general formula (1) is used, the degree of vacuum and the heating temperature of the vapor deposition source need to be selected according to the melting point, boiling point, etc. of the material to be vapor deposited. However, in the case of an organic material, it is generally in the range of 100 to 500 ° C., and it is preferably as high as possible without causing decomposition.

  The rate at which the raw material compound vaporized by heating is deposited on the substrate by a vapor deposition process to form a thin film, that is, the vapor deposition rate, can be measured by a film thickness meter. As the film thickness meter, a known apparatus can be used (for example, a crystal oscillation type), and examples thereof include CRTM-9000 manufactured by ULVAC. The sensor (quartz crystal resonator) provided in the vapor deposition tank is preferably as close to the substrate on which vapor deposition is possible. This is because it is possible to monitor the deposition rate more accurately.

  In addition, in order to monitor the accurate deposition rate during film formation, the film thickness measured by the film thickness meter and the actual film thickness must be calibrated. For example, it can be calibrated by depositing a raw material on the substrate about 100 to 500 nm and comparing the value of the film thickness meter with the actual film thickness. At this time, it is important to use a raw material (organic EL material) to be deposited. This is because the density varies depending on the compound.

  The actual film thickness may be a known method, for example, a contact type or a non-contact type, but can be measured using a film thickness meter.

  When the azacarbazole compound represented by the general formula (1) according to the present invention is formed into a thin film by vacuum vapor deposition, the reason for improving the performance of the obtained organic EL device by increasing the vapor deposition rate is as follows. It is thought as follows.

  Usually, an amorphous film is used as the organic thin film constituting the organic EL element. In the case of a crystalline or microcrystalline film, it is known that the characteristics of the organic EL are poor. Therefore, in order to obtain a good organic EL element, an amorphous film having a good film morphology is required in the organic material layer of the organic EL element.

  In the present invention, it is assumed that the efficiency is improved by depositing the compound represented by the general formula (1) at a high deposition rate of 0.5 nm or more, which is related to the morphology of the film. Yes. That is, it is considered that the higher the deposition rate, the higher the amorphousness of the compound film represented by the general formula (1) of the present invention is, and the film is homogeneous and has good adhesion to the adjacent layer. ing.

  However, the higher the deposition rate, the less good it is, and it must be in a range where the compound does not decompose. Specifically, it is in the range of 0.5 to 10 nm / s, more preferably in the range of 1 to 5 nm / s.

  Therefore, it is preferable that the decomposition temperature of the compound to be deposited is separately measured with a thermogravimetric apparatus (TGA) or the like. Thereby, the limit of the deposition rate can be determined by monitoring the temperature of the deposition source.

  That is, it is presumed that these are largely related to the kinetic energy possessed by molecules during vapor deposition.

  For example, the compound represented by the general formula (1) is preferably contained and used in the hole blocking layer. In other words, a layer formed by high-speed deposition of the compound is more preferable as the hole blocking layer. It is.

  The same applies to the co-deposited film, and it is presumed that the organic vapor deposition rate is set to 0.5 nm or more to uniformly mix with different organic EL materials.

  Even in the case of co-evaporation, the compound represented by the general formula (1) is, for example, co-deposited with a phosphorescent dopant as a host compound (forming a light emitting layer), an electron transport layer, an electron injection As a layer or the like, a co-evaporated layer of the compound represented by the general formula (1) according to the present invention and an alkali metal such as cesium (Cs), an alkaline earth metal, or a salt thereof (or an organic salt) may be used. In the case of forming the film, the compound represented by the general formula (1) seems to give an amorphous film having good morphology when the deposition rate is high as described above, and gives a film having good performance.

  Further, other organic EL materials may be mixed. In that case, co-evaporation of 3 or more elements is performed.

  Next, the compound represented by the general formula (1) will be described.

<< Compound Represented by Formula (1) >>
In the general formula (1), Z ₁ represents an aromatic heterocyclic ring which may have a substituent, and Z ₂ represents an aromatic heterocyclic ring or an aromatic hydrocarbon ring which may have a substituent. , Z ₃ represents a divalent linking group or a simple bond. R ₁₀₁ represents a hydrogen atom or a substituent.

In the general formula (1), examples of the aromatic heterocycle represented by Z ₁ and Z ₂ include a furan ring, a thiophene ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, a benzimidazole ring, Diazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, indole ring, benzimidazole ring, benzothiazole ring, benzoxazole ring, quinoxaline ring, quinazoline ring, phthalazine ring, carbazole ring, carboline ring, carboline ring And a ring in which the carbon atom of the hydrocarbon ring is further substituted with a nitrogen atom. Furthermore, the aromatic heterocyclic ring may have a substituent represented by R ₁₀₁ described later.

In the general formula (1), examples of the aromatic hydrocarbon ring represented by Z ₂ include benzene ring, biphenyl ring, naphthalene ring, azulene ring, anthracene ring, phenanthrene ring, pyrene ring, chrysene ring, naphthacene ring, triphenylene. Ring, o-terphenyl ring, m-terphenyl ring, p-terphenyl ring, acenaphthene ring, coronene ring, fluorene ring, fluoranthrene ring, naphthacene ring, pentacene ring, perylene ring, pentaphen ring, picene ring, pyrene Ring, pyranthrene ring, anthraanthrene ring and the like. Furthermore, the aromatic hydrocarbon ring may have a substituent represented by R ₁₀₁ described later.

In the general formula (1), examples of the substituent represented by R ₁₀₁ include an alkyl group (eg, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group). Group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (eg, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (eg, vinyl group, allyl group, etc.), alkynyl group (eg, ethynyl group, propargyl group, etc.) Etc.), aryl groups (eg phenyl group, naphthyl group etc.), aromatic heterocyclic groups (eg furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group, pyrazolyl group) , Thiazolyl group, quinazolinyl group, phthalazinyl group, etc.), heterocyclic group (eg Pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxyl group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cyclo An alkoxyl group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), an aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), an alkylthio group (eg, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, Octylthio group, dodecylthio group etc.), cycloalkylthio group (eg cyclopentylthio group, cyclohexylthio group etc.), arylthio group (eg phenylthio group, naphthylthio group etc.), alkoxycarbonyl group (eg meso Ruoxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, Aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclyl group) Hexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group) Octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonyl) Amino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthy Carbonylamino group, etc.), carbamoyl group (eg, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylamino) Carbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group) , Dodecylureido group, phenylureido group naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethyl) Rufinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group) , Butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group (phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group etc.), amino group (for example, amino group, ethyl group) Amino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridy Amino groups, etc.), halogen atoms (eg, fluorine atoms, chlorine atoms, bromine atoms, etc.), fluorinated hydrocarbon groups (eg, fluoromethyl groups, trifluoromethyl groups, pentafluoroethyl groups, pentafluorophenyl groups, etc.), And cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.).

  These substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

  Preferred substituents are an alkyl group, a cycloalkyl group, a fluorinated hydrocarbon group, an aryl group, and an aromatic heterocyclic group.

  As the divalent linking group, in addition to hydrocarbon groups such as alkylene, alkenylene, alkynylene, and arylene, those containing a hetero atom may be used, and a thiophene-2,5-diyl group, pyrazine-2, It may be a divalent linking group derived from a compound having an aromatic heterocyclic ring (also called a heteroaromatic compound) such as a 3-diyl group, or may be a chalcogen atom such as oxygen or sulfur. . Further, it may be a group such as an alkylimino group, a dialkylsilanediyl group, or a diarylgermandiyl group that joins and connects heteroatoms.

  A mere bond is a bond that directly bonds the connecting substituents together.

In the present invention, Z _{1 in the} general formula (1) is preferably a 6-membered ring. Thereby, luminous efficiency can be made higher. Furthermore, the lifetime can be further increased.

In the present invention, it is preferable that the Z ₂ in the general formula (1) is a 6-membered ring. Thereby, luminous efficiency can be made higher. Furthermore, the lifetime can be further increased.

Furthermore, it is preferable that Z ₁ and Z _{2 in} the general formula (1) are both 6-membered rings because the luminous efficiency can be further increased. Furthermore, it is preferable because the lifetime can be further increased.

  Preferred among the compounds represented by the general formula (1) are compounds represented by the following general formulas (1-1) to (1-13).

In the general formula (1-1), R _{501 to} R ₅₀₇ each independently represent a hydrogen atom or a substituent.

  By using the compound represented by the general formula (1-1), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-2), R _{511 to} R ₅₁₇ each independently represent a hydrogen atom or a substituent.

  By using the compound represented by the general formula (1-2), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-3), R _{522 to} R ₅₂₇ each independently represent a hydrogen atom, an alkyl group, or an aryl group .

  By using the compound represented by the general formula (1-3), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-4), R _{531 to} R ₅₃₇ each independently represents a hydrogen atom or a substituent.

  By using the compound represented by the general formula (1-4), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-5), R _{542 to} R ₅₄₈ each independently represents a hydrogen atom, an alkyl group, or an aryl group .

  By using the compound represented by the general formula (1-5), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-6), R _{552 to} R ₅₅₈ each independently represent a hydrogen atom, an alkyl group, or an aryl group .

  By using the compound represented by the general formula (1-6), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-7), R _{561 to} R ₅₆₇ each independently represent a hydrogen atom or a substituent.

  By using the compound represented by the general formula (1-7), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-8), R _{571 to} R ₅₇₇ each independently represent a hydrogen atom or a substituent.

  By using the compound represented by the general formula (1-8), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-9), R represents a hydrogen atom, an alkyl group, or an aryl group . The plurality of R may be the same or different.

  By using the compound represented by the said General formula (1-9), it can be set as an organic electroluminescent element with higher luminous efficiency. Furthermore, it can be set as a longer life organic EL element.

In the general formula (1-10), R represents a hydrogen atom, an alkyl group, or an aryl group . The plurality of R may be the same or different.

  By using the compound represented by the general formula (1-10), an organic EL device with higher luminous efficiency can be obtained. Furthermore, a long-life organic EL element can be obtained.

  Moreover, what is preferable among the compounds represented by the general formula (1) is a compound having at least one group represented by any one of the following general formulas (2-1) to (2-8).

In the formula, R _{502 to} R ₅₀₇ , R _{512 to} R ₅₁₇ , R _{522 to} R ₅₂₇ , R _{532 to} R ₅₃₇ , R _{542 to} R ₅₄₈ , R _{552 to} R ₅₅₈ , R _{562 to} R ₅₆₇ , R _{572 to} R ₅₇₇ Each independently represents a hydrogen atom or a substituent, and the substituents may be the same or different.

In particular, it is more preferable to have 2 to 4 groups represented by any one of the general formulas (2-1) to (2-8) in the molecule. In this case, the structure represented by the general formula (1) includes a case where the portion excluding R ₁₀₁ is replaced by the general formulas (2-1) to (2-8).

At this time, in particular, a compound represented by the following general formula (3) or (4) is used in the present invention .

In the general formula (3), R _{601 to} R ₆₀₆ are hydrogen atoms, or the following general formulas (1-3), (1-5), (1-6), (1-9) or (1-10) ), But two or three of R _{601 to} R ₆₀₆ are the general formulas (1-3), (1-5), (1-6), (1-9) Or represents the group represented by (1-10). However, two or three groups represented by the general formula (1-3), (1-5), (1-6), (1-9) or (1-10) are not adjacent.

  By using the compound represented by the general formula (3), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (4), R _{611 to} R ₆₂₀ are a hydrogen atom, an alkyl group, an aryl group, a halogen atom, a group in which adjacent groups are combined to form a benzene ring, or the following general formula (1-3 ), (1-5), (1-6), (1-9) or (1-10), but two or four of R _{611 to} R ₆₂₀ are general ones. The group represented by Formula (1-3), (1-5), (1-6), (1-9) or (1-10) is represented. However, when there are two groups represented by formulas (1-3), (1-5), (1-6), (1-9) or (1-10), R ₆₁₃ and R ₆₁₈ are The group represented by the general formula (1-3), (1-5), (1-6), (1-9) or (1-10) is represented, and the general formula (1-3), ( 1-5), (1-6), (1-9)
Or when there are four groups represented by (1-10), R ₆₁₂ , R ₆₁₄ , R ₆₁₇ and R ₆₁₉ are the general formulas (1-3), (1-5), (1-6), ( 1-9) represents a group represented by (1-10).

  By using the compound represented by the general formula (4), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (5), R _{621 to} R ₆₂₃ represent a hydrogen atom or a substituent, and at least one of R _{611 to} R ₆₂₀ is represented by the general formulas (2-1) to (2-4). The group represented by either is represented.

  By using the compound represented by the general formula (5), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (6), R _{631 to} R ₆₄₅ represent a hydrogen atom or a substituent, and at least one of R _{631 to} R ₆₄₅ is represented by the general formulas (2-1) to (2-4). The group represented by either is represented.

  By using the compound represented by the general formula (6), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (7), R _{651 to} R ₆₅₆ represent a hydrogen atom or a substituent, and at least one of R _{651 to} R ₆₅₆ is represented by the general formulas (2-1) to (2-4). The group represented by either is represented. na represents an integer of 0 to 5, and nb represents an integer of 1 to 6, but the sum of na and nb is 6.

  By using the compound represented by the general formula (7), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (8), R _{661 to} R _{672 each} represents a hydrogen atom or a substituent, and at least one of R _{661 to} R ₆₇₂ is represented by the general formulas (2-1) to (2-4). The group represented by either is represented.

  By using the compound represented by the general formula (8), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (9), R _{681 to} R ₆₈₈ represent a hydrogen atom or a substituent, and at least one of R _{681 to} R ₆₈₈ is represented by the general formulas (2-1) to (2-4). The group represented by either is represented.

  By using the compound represented by the general formula (9), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the general formula (10), R _{691 to} R ₇₀₀ represent a hydrogen atom or a substituent, and at least one of R _{691 to} R ₇₀₀ is represented by the general formulas (2-1) to (2-4). The group represented by either is represented.

In the general formula (10), the divalent linking group represented by L ₁ is an alkylene group (for example, ethylene group, trimethylene group, tetramethylene group, propylene group, ethylethylene group, pentamethylene group, hexamethylene). Group, 2,2,4-trimethylhexamethylene group, heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, undecamethylene group, dodecamethylene group, cyclohexylene group (for example, 1,6-cyclohexanediyl group, etc.) ), Cyclopentylene group (eg, 1,5-cyclopentanediyl group, etc.), alkenylene group (eg, vinylene group, propenylene group, etc.), alkynylene group (eg, ethynylene group, 3-pentynylene group, etc.), In addition to hydrocarbon groups such as arylene groups, groups containing heteroatoms (eg, —O , -S- and the like, a divalent group containing a chalcogen atom, -N (R)-group, wherein R represents a hydrogen atom or an alkyl group, and the alkyl group in the general formula (1), And the same as the alkyl group represented by R ₁₀₁ .

  In each of the alkylene group, alkenylene group, alkynylene group, and arylene group, at least one of carbon atoms constituting the divalent linking group is a chalcogen atom (oxygen, sulfur, etc.) or -N (R). -It may be substituted with a group or the like.

Furthermore, as the divalent linking group represented by L ₁ , for example, a group having a divalent heterocyclic group is used. For example, an oxazolediyl group, a pyrimidinediyl group, a pyridazinediyl group, a pyrandiyl group, a pyrrolindiyl group. Group, imidazoline diyl group, imidazolidine diyl group, pyrazolidine diyl group, pyrazoline diyl group, piperidine diyl group, piperazine diyl group, morpholine diyl group, quinuclidine diyl group and the like, and thiophene-2,5- A divalent linking group derived from a compound having an aromatic heterocyclic ring (also referred to as a heteroaromatic compound) such as a diyl group or a pyrazine-2,3-diyl group may be used.

  Further, it may be a group that meets and links heteroatoms such as an alkylimino group, a dialkylsilanediyl group, or a diarylgermandiyl group.

  By using the compound represented by the general formula (10), an organic EL device with higher luminous efficiency can be obtained. Furthermore, it can be set as a longer life organic EL element.

In the compounds represented by the general formula (11) to the general formula (15), the substituents represented by R ₁ and R ₂ are the substituents represented by R ₁₀₁ in the general formula (1). At the same time as the group.

In the general formula (15), examples of the 6-membered aromatic heterocyclic ring each containing at least one nitrogen atom represented by Z ₁ , Z ₂ , Z ₃ , and Z ₄ include a pyridine ring and a pyridazine ring. , Pyrimidine ring, pyrazine ring and the like.

In the general formula (16), examples of the 6-membered aromatic heterocycle each containing at least one nitrogen atom represented by Z ₁ and Z ₂ include a pyridine ring, a pyridazine ring, a pyrimidine ring, and a pyrazine ring. Etc.

In the general formula (16), the arylene groups represented by Ar ₁ and Ar ₂ include o-phenylene group, m-phenylene group, p-phenylene group, naphthalenediyl group, anthracenediyl group, naphthacenediyl group, and pyrenediyl group. Group, naphthylnaphthalenediyl group, biphenyldiyl group (for example, 3,3′-biphenyldiyl group, 3,6-biphenyldiyl group, etc.), terphenyldiyl group, quaterphenyldiyl group, kinkphenyldiyl group, sexi Examples thereof include a phenyldiyl group, a septiphenyldiyl group, an octylphenyldiyl group, a nobiphenyldiyl group, and a deciphenyldiyl group. The arylene group may further have a substituent described later.

In the general formula (16), the divalent aromatic heterocyclic groups represented by Ar ₁ and Ar ₂ are furan ring, thiophene ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, triazine ring, benzo Imidazole ring, oxadiazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, indole ring, benzimidazole ring, benzothiazole ring, benzoxazole ring, quinoxaline ring, quinazoline ring, phthalazine ring, carbazole ring, carboline ring, And divalent groups derived from a ring in which the carbon atom of the hydrocarbon ring constituting the carboline ring is further substituted with a nitrogen atom. Furthermore, the aromatic heterocyclic group may have a substituent represented by R ₁₀₁ .

In the general formula (16), the divalent linking group represented by L has the same meaning as the divalent linking group represented by L ₁ in the general formula (10), but is preferably an alkylene group. , —O—, —S— and the like, are divalent groups containing a chalcogen atom, most preferably an alkylene group.

In the general formula (17), in Ar _1, Ar _2, the arylene group represented by each, in the general formula (16), is synonymous with the arylene group represented by each of Ar _1, Ar _2.

In the general formula (17), an aromatic heterocyclic group represented by each of Ar _1, Ar _2, in the general formula (16), the divalent aromatic heterocyclic ring represented by each of Ar _1, Ar ₂ Synonymous with group.

In the general formula (17), examples of the 6-membered aromatic heterocycle each containing at least one nitrogen atom represented by Z ₁ , Z ₂ , Z ₃ , and Z ₄ include a pyridine ring and a pyridazine ring. , Pyrimidine ring, pyrazine ring and the like.

In the general formula (17), the divalent linking group represented by L has the same meaning as the divalent linking group represented by L ₁ in the general formula (10), but is preferably an alkylene group. , —O—, —S— and the like, are divalent groups containing a chalcogen atom, most preferably an alkylene group.

Hereinafter, the compound represented by the general formula according to the present invention (3) or (4), and shows a specific example that is a reference, the present invention is not limited thereto.

  Although the typical synthesis example of the compound based on this invention is shown below, this invention is not limited to these.

  << Synthesis of Exemplified Compound 73 >>

  To a mixed solution obtained by adding 6.87 g of 4,4′-diiodobiphenyl and 6.00 g of β-carboline in 50 ml of N, N-dimethylacetamide, 4.5 g of copper powder and 7.36 g of potassium carbonate were added for 15 hours. Heated to reflux. After allowing to cool, water chloroform was added, and insolubles were removed by filtration. The organic layer was separated, washed with water and saturated brine, and concentrated under reduced pressure. The obtained residue was dissolved in acetic acid, treated with activated carbon, and recrystallized to give 4.2 g of colorless crystals of Exemplified Compound 73. Got.

The structure of Exemplified Compound 73 was confirmed by ¹ H-NMR spectrum and mass spectrometry spectrum. The physical property data and spectrum data of the exemplified compound 73 are shown below.

Colorless crystals, melting point 200 ° C
MS (FAB) m / z: 487 (M + 1)
¹ H-NMR (400 MHz, CDCl ₃ ): δ / ppm 7.3-7.5 (m, 2H), 7.5-7.6 (m, 4H), 7.7-7.8 (m, 4H), 7.9-8.0 (m, 4H), 8.06 (d, J = 5.1 Hz, 2H), 8.24 (d, J = 7.8 Hz, 2H), 8.56 ( d, J = 5.1 Hz, 2H), 8.96 (s, 2H)
<< Synthesis of Exemplary Compound 74 >>

  0.32 g of palladium acetate and 1.17 g of tri-tert-butylphosphine were dissolved in 10 ml of anhydrous toluene, 50 mg of sodium borohydride was added, and the mixture was stirred at room temperature for 10 minutes, then δ-carboline 5.00 g, 4, 4 5.87 g of '-diiodobiphenyl and 3.42 g of sodium tert-butoxide were dispersed in 50 ml of anhydrous xylene and stirred at reflux temperature for 10 hours under a nitrogen atmosphere. The resulting reaction mixture was allowed to cool, chloroform and water were added to separate the organic layer, the organic layer was washed with water and saturated brine, and then concentrated under reduced pressure. The resulting residue was dissolved in tetrahydrofuran. After the activated carbon treatment, 5.0 g of colorless crystals of Exemplified Compound 74 was obtained by recrystallization.

The structure of exemplary compound 74 was confirmed by ¹ H-NMR spectrum and mass spectrometry spectrum. The physical property data and spectrum data of the exemplified compound 74 are shown below.

MS (FAB) m / z: 487 (M + 1)
¹ H-NMR (400 MHz, CDCl ₃ ): δ / ppm 7.37 (dd, J = 4.7 Hz, J = 8.3 Hz, 2H), 7.4-7.5 (m, 2H), 7. 5-7.6 (m, 4H), 7.7-7.8 (m, 4H), 7.81 (dd, J = 1.2 Hz, J = 8.3 Hz, 2H), 7.9-8 0.0 (m, 4H), 8.48 (d, J = 7.8 Hz, 2H), 8.65 (dd, J = 1.2 Hz, J = 4.6 Hz, 2H)
<< Synthesis of Exemplary Compound 60 >>

  To a mixed solution in which 6.87 g of 4,4′-diiodobiphenyl and 6.00 g of γ-carboline were added to 50 ml of N, N-dimethylacetamide, 4.5 g of copper powder and 7.36 g of potassium carbonate were added for 15 hours. Heated to reflux. After allowing to cool, water chloroform was added, and insolubles were removed by filtration. The organic layer was separated, washed with water and saturated brine, and concentrated under reduced pressure. The obtained residue was subjected to silica gel chromatography and crystallized in dichloromethane / cyclohexane to give colorless crystals of Exemplified Compound 60. 4.3 g was obtained.

The structure of the exemplary compound 60 was confirmed by ¹ H-NMR spectrum and mass spectrometry spectrum. The physical property data and spectrum data of the exemplary compound 60 are shown below.

MS (FAB) m / z: 487 (M + 1)
¹ H-NMR (400 MHz, CDCl ₃ ): δ / ppm 7.4-7.4 (m, 4H), 7.4-7.5 (m, 4H), 7.7-7.8 (m, 4H) 7.9-8.0 (m, 4H), 8.25 (d, J = 7.8 Hz, 2H), 8.57 (d, J = 5.6 Hz, 2H), 9.42 (s) , 1H)
<< Synthesis of Exemplary Compound 144 >>

  0.16 g of palladium acetate and 0.58 g of tri-tert-butylphosphine are dissolved in 10 ml of anhydrous toluene, 25 mg of sodium borohydride is added and stirred for 10 minutes at room temperature, then 2.00 g of δ-carboline, intermediate a3 20 g and 1.37 g of sodium tert-butoxide were dispersed in 50 ml of anhydrous xylene and stirred at reflux temperature for 10 hours under a nitrogen atmosphere. After allowing to cool, chloroform and water are added to separate the organic layer. The organic layer is washed with water and saturated brine and then concentrated under reduced pressure. The resulting residue is recrystallized from acetic acid to give colorless colorless compound of Exemplified Compound 144. 1.5 g of crystals were obtained.

The structure of exemplary compound 144 was confirmed by ¹ H-NMR spectrum and mass spectrometry spectrum. The spectrum data of the exemplary compound 144 are as follows.

MS (FAB) m / z: 647 (M + 1)
¹ H-NMR (400 MHz, CDCl ₃ ) δ / ppm 1.80 (S, 12H), 7.27 (S, 4H), 7.34 (dd, J = 4.9 Hz, J = 8.3 Hz, 2H ), 7.3-7.4 (m, 2H), 7.4-7.5 (m, 12H), 7.76 (dd, J = 1.3 Hz, J = 8.3 Hz, 2H), 8 .45 (d, J = 7.8 Hz, 2H), 8.63 (dd, J = 1.3 Hz, J = 4.9 Hz, 2H)
<< Synthesis of Exemplary Compound 143 >>

  Add 4,5'-dichloro-3,3'-bipyridyl 0.85 g, diamine b 0.59 g, dibenzylideneacetone palladium 44 mg, imidazolium salt 36 mg, sodium tert-butoxide 1.09 g to 5 ml dimethoxyethane, 80 The mixture was stirred at 24 ° C. for 24 hours. After allowing to cool, chloroform and water were added to separate the organic layer, and the organic layer was washed with water and saturated brine and then concentrated under reduced pressure. The obtained residue was recrystallized from ethyl acetate to give Example Compound 143. 0.3 g of colorless crystals was obtained.

The structure of the exemplary compound 143 was confirmed by ¹ H-NMR spectrum and mass spectrometry spectrum. The spectrum data of the exemplary compound 143 are shown below.

MS (FAB) m / z 639 (M + 1)
¹ H-NMR (400 MHz, CDCl ₃ ): δ / ppm 7.46 (d, J = 5.7 Hz, 4H), 7.6-7.7 (m, 4H), 7.8-7.9 ( m, 4H), 8.67 (d, J = 5.7 Hz, 4H), 9.51 (S, 4H)
<< Synthesis of Exemplary Compound 145 >>
In the synthesis of Exemplified Compound 143, the same procedure was carried out except that one pyridine ring of 4,4'-dichloro-3,3'-bipyridyl was changed to benzene and 3- (2-chlorophenyl) -4-chloropyridine was used. Example compound 145 was synthesized.

The structure of exemplary compound 145 was confirmed by ¹ H-NMR spectrum and mass spectrometry spectrum. The spectrum data of the exemplary compound 145 are shown below.

MS (FAB) m / z 637 (M + 1)
¹ H-NMR (400 MHz, CDCl ₃ ) δ / ppm 7.3-7.4 (m, 2H), 7.6-7.7 (m, 4H), 7.7-7.8 (m, 4H) ) 7.8-7.9 (m, 4H), 8.06 (d, J = 5.3 Hz, 2H), 8.23 (d, J = 7.8 Hz, 2H), 8.56 (d, J = 5.3 Hz, 2H), 8.96 (S, 2H)
In addition to the above synthesis examples, the azacarbazole rings and chloroplasts of these compounds are described in J. Chem. Soc. Perkin Trans. 1, 1505-1510 (1999), Pol. J. et al. Chem. , 54, 1585 (1980), (Tetrahedron Lett. 41 (2000), 481-484). Introduction of the synthesized azacarbazole ring or its chloroplast to the core or linking group of an aromatic ring, a heterocyclic ring, an alkyl group, etc. is known such as Ullman coupling, coupling using Pd catalyst, Suzuki coupling, etc. This method can be used.

  The compound according to the present invention preferably has a molecular weight of 400 or more, more preferably 450 or more, still more preferably 600 or more, and particularly preferably a molecular weight of 800 or more. Thereby, the glass transition temperature is raised, the thermal stability is improved, and the life can be further extended.

  The compound represented by the general formula (1) according to the present invention is used as a constituent component of a constituent layer of an organic EL element to be described later. In the present invention, the light emitting layer that is a constituent layer of the organic EL element of the present invention or Although contained in the adjacent layer of the light emitting layer, the adjacent layer is preferably a hole blocking layer. Further, it is preferably used as a host compound in the light emitting layer, and is preferably used as a hole blocking material in the hole blocking layer.

  However, from the viewpoint of controlling various physical properties of the organic EL element, the compound according to the present invention may be used in other constituent layers of the organic EL element as necessary.

  The compound according to the present invention is a material for organic EL elements (backlight, flat panel display, illumination light source, display element, electrophotographic light source, recording light source, exposure light source, reading light source, sign, signboard, interior, optical communication device, etc.) Other uses include organic semiconductor laser materials (recording light source, exposure light source, reading light source optical communication device, electrophotographic light source, etc.), electrophotographic photosensitive material, organic TFT element It can be used in a wide range of fields such as materials (organic memory elements, organic arithmetic elements, organic switching elements), organic wavelength conversion element materials, photoelectric conversion element materials (solar cells, optical sensors, etc.).

  Next, the constituent layers of the organic EL device of the present invention will be described in detail.

In this invention, although the preferable specific example of the layer structure of an organic EL element is shown below, this invention is not limited to these.
(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode << Anode >>
As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such electrode materials include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ and ZnO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. For the anode, a thin film may be formed by depositing these electrode materials by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when the pattern accuracy is not required (100 μm or more) Degree), a pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered. When light emission is extracted from the anode, it is desirable that the transmittance is greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

"cathode"
On the other hand, as the cathode, a material having a low work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like. Among these, a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function value than this, such as a magnesium / silver mixture, magnesium, from the viewpoint of electron injectability and durability against oxidation, etc. / Aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. In order to transmit the emitted light, if either the anode or the cathode of the organic EL element is transparent or translucent, the light emission luminance is improved, which is convenient.

  Moreover, after producing the said metal with a film thickness of 1-20 nm on a cathode, a transparent or semi-transparent cathode can be produced by producing the electroconductive transparent material quoted by description of the anode on it, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

  Next, an injection layer, a blocking layer, an electron transport layer and the like used as the constituent layers of the organic EL element of the present invention will be described.

<< Injection layer: electron injection layer, hole injection layer >>
The injection layer is provided as necessary, and there are an electron injection layer and a hole injection layer, and as described above, exists between the anode and the light emitting layer or the hole transport layer, and between the cathode and the light emitting layer or the electron transport layer. You may let them.

  An injection layer is a layer provided between an electrode and an organic layer in order to reduce drive voltage and improve light emission luminance. “Organic EL element and its forefront of industrialization (issued by NTT Corporation on November 30, 1998) 2), Chapter 2, “Electrode Materials” (pages 123 to 166) in detail, and includes a hole injection layer (anode buffer layer) and an electron injection layer (cathode buffer layer).

  The details of the anode buffer layer (hole injection layer) are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. As a specific example, copper phthalocyanine is used. Examples thereof include a phthalocyanine buffer layer represented by an oxide, an oxide buffer layer represented by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

  The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. Metal buffer layer typified by lithium, alkali metal compound buffer layer typified by lithium fluoride, alkaline earth metal compound buffer layer typified by magnesium fluoride, oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is desirably a very thin film, and although it depends on the material, the film thickness is preferably in the range of 0.1 nm to 5 μm.

<Blocking layer: hole blocking layer, electron blocking layer>
As described above, the blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film. For example, as described in JP-A Nos. 11-204258 and 11-204359, and “Organic EL elements and the forefront of industrialization” (issued on November 30, 1998 by NTS Corporation). There is a hole blocking layer.

  The hole blocking layer is an electron transport layer in a broad sense, and is made of a hole blocking material that has a function of transporting electrons but has a very small ability to transport holes, and blocks holes while transporting electrons. Thus, the probability of recombination of electrons and holes can be improved.

  The hole blocking layer of the organic EL device of the present invention is preferably provided adjacent to the light emitting layer. In this invention, it is preferable to contain the compound which concerns on this invention mentioned above as a hole blocking material of a hole blocking layer. Thereby, it can be set as an organic EL element with much higher luminous efficiency. Furthermore, the lifetime can be further increased.

  On the other hand, the electron blocking layer is a hole transport layer in a broad sense, made of a material that has a function of transporting holes and has a very small ability to transport electrons, and blocks electrons while transporting holes. Thus, the probability of recombination of electrons and holes can be improved.

<Light emitting layer>
The light-emitting layer is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer. It may be an interface with an adjacent layer. The light emitting layer may be a layer having a single composition, or may be a laminated structure including a plurality of layers having the same or different compositions.

  In the present invention, at least one light emitting layer contains at least one compound represented by the general formula (1) and at least one phosphorescent compound having a phosphorescence 0-0 band of 480 nm or less. Preferably it is.

  When the light-emitting layer comprises two or more kinds of compounds as described above, the main component constituting the light-emitting layer is called a host compound or simply a host, and the added compound is called a dopant, and phosphorescent organic electroluminescence In the device, the phosphorescent dopant emits light by energy transfer from the host compound to the phosphorescent dopant, and as a result, phosphorescence emission is extracted. In the present invention, a configuration in which the compound represented by the general formula (1) is a host compound and the phosphorescent compound is a dopant is preferable. Only one type of phosphorescent dopant may be used, or a plurality of types may be used. When an organic electroluminescent element is formed by laminating a plurality of light emitting layers, the phosphorescent dopant contained in each layer may be the same or different, or may be a single type or a plurality of types. May be.

  The “phosphorescent compound” in the present invention is a compound in which light emission from an excited triplet is observed, and is a compound having a phosphorescence quantum yield of 0.001 or more at 25 ° C. The phosphorescence quantum yield is preferably 0.01 or more, more preferably 0.1 or more. The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence emitting compound used in the present invention is only required to achieve the phosphorescence quantum yield in any solvent.

  The present invention is characterized in that the general formula (1) and a phosphorescent compound having a phosphorescence 0-0 band of 480 nm or less are used in combination, but phosphorescence emission having a phosphorescence 0-0 band of 480 nm or less is used. Specifically, the active compound may be any compound that is stable in the excited triplet state formed at room temperature (15 to 30 degrees) and satisfies the wavelength. By using such a phosphorescent compound as a dopant in the light emitting layer, a light emitting organic EL device having high internal quantum efficiency can be realized. Specifically, Y.M. Wang et al. , Appl. Phys. Lett. 79, No. 4, 449-451 (2001), C.I. Adachi et al. 79, No. 13, 2082-2084 (2001), and the like. Preferably, a complex having a central metal such as iridium, osmium, rhodium and platinum and an organic ligand is used. More preferably, it is iridium or a rhodium complex.

  The ligand needs to be designed so that the phosphorescence 0-0 band is 480 nm or less. Specific means include a method of introducing an electron-withdrawing group such as a fluorine atom or a trifluoromethyl group, a method of introducing a twisted structure by introducing a bulky substituent, and an alkylene as a linking group between the aromatic rings of the ligand. A method of introducing a chain is conceivable.

  A method for measuring the 0-0 band of phosphorescence in the present invention will be described.

  First, a method for measuring a phosphorescence spectrum will be described.

The luminescent host compound to be measured is dissolved in a well-deoxygenated mixed solvent of ethanol / methanol = 4/1 (vol / vol), placed in a phosphorescence measurement cell, and then irradiated with excitation light at a liquid nitrogen temperature of 77 ° K. The emission spectrum at 100 ms after the excitation light irradiation is measured. Since phosphorescence has a longer emission lifetime than fluorescence, it can be considered that light remaining after 100 ms is almost phosphorescence. For compounds with a phosphorescence lifetime shorter than 100 ms, measurement may be performed with a shorter delay time, but phosphorescence and fluorescence cannot be separated if the delay time is shortened so that it cannot be distinguished from fluorescence. Since this is a problem, it is necessary to select a delay time that can be separated.

  In addition, for a compound that cannot be dissolved in the solvent system, any solvent that can dissolve the compound may be used (substantially, the solvent effect of the phosphorescence wavelength is negligible in the above measurement method).

  Next, the 0-0 band is determined. In the present invention, the emission maximum wavelength that appears on the shortest wavelength side in the phosphorescence spectrum chart obtained by the above-described measurement method is defined as the 0-0 band.

  Since the phosphorescence spectrum usually has a low intensity, when it is enlarged, it may be difficult to distinguish between noise and peak. In such a case, the emission spectrum immediately after the excitation light irradiation (for convenience, this is referred to as a steady light spectrum) is expanded, and the emission spectrum 100 ms after the excitation light irradiation (for convenience, this is referred to as a phosphorescence spectrum) is superimposed on the phosphorous. It can be determined by reading the peak wavelength from the stationary light spectrum part derived from the light spectrum. Further, by performing a smoothing process on the phosphorescence spectrum, it is possible to separate the noise and the peak and read the peak wavelength. As the smoothing process, a smoothing method of Savitzky & Golay can be applied.

  The phosphorescence 0-0 band measured by this method is, for example, 465 nm as a result of measurement for the following exemplary compound D-10.

  Examples of these phosphorescent compounds having a phosphorescence 0-0 band of 480 nm or less are shown below, but are not limited thereto.

  A case where the compound represented by the general formula (1) according to the present invention is used as a host compound of the light emitting layer and a phosphorescent compound having a phosphorescence 0-0 band of 480 nm or less is used as a dopant is preferable. The doping amount of the phosphorescent compound with respect to the host compound is more than 0% by mass and less than 30% by mass, preferably 0.1% by mass to 20% by mass, and more preferably less than 1 to 15% by mass. It is.

  In the present invention, it is essential to use a phosphorescent compound having a phosphorescence 0-0 band of 480 nm or less, but other known phosphorescent compounds may be used in combination. Specific examples thereof include, but are not limited to, compounds described in the following patent publications.

  WO00 / 70655, JP 2002-280178, 2001-181616, 2002-280179, 2001-181617, 2002-280180, 2001-247859, 2002-299060, 2001-313178, 2002-302671, JP 2001-345183, 2002-324679, WO 02/15645, JP 2002-332291, 2002-50484, 2002-332292, 2002-83684, JP 2002-540572, JP 2002-117978, 2002. -338588, 2002-170684, 2002-352960, WO 01/93642, JP2002-50483, 2002-1000047, 2002-17367 4, 2002-359082, 2002-175842, 2002-363552, 2002-184582, 2003-7469, JP2002-525808, JP2003-7471, JP2002-525833, JP2003-31366. 2002-226495, 2002-234894, 2002-2335076, 2002-241751, 2002-3179979, 2001-319780, 2002-62824, 2002-1000047, 2002-203679, 2002-343572. , 2002-203678, etc.

  In addition to a dopant made of a phosphorescent compound, a fluorescent dopant may be added to the light emitting layer. Typical examples of the fluorescent dopant include a coumarin dye, a pyran dye, a cyanine dye, and a croconium. Dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes, stilbene dyes, polythiophene dyes, rare earth complex phosphors, and other known fluorescent compounds Etc.

  In the present invention, the compound represented by the general formula (1) is used, but a known host compound can be used in combination, and in addition to the light emitting layer containing the compound represented by the general formula (1), a light emitting layer is provided. A known host compound may be used. Known host compounds are not particularly limited in structure, but typically carbazole derivatives, triarylamine derivatives, aromatic borane derivatives, nitrogen-containing heterocyclic compounds, thiophene derivatives, furan derivatives, oligoarylene compounds, etc. And a compound having a phosphorescence 0-0 band of 450 nm or less.

  These host compounds may be low molecular compounds, high molecular compounds having repeating units, or low molecular compounds having a polymerizable group such as a vinyl group or an epoxy group (evaporation polymerizable light emitting host).

  As the host compound, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable.

  Specific examples of the host compound include compounds described in the following documents.

  JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445, 2002-343568, 2002-141173, 2002-352957, 2002-203683, 2002-363227 2002-231453, 2003-3165, 2002-234888, 2003-27048, 2002-255934, JP-A 2002-260861, 002-280183, same 2002-299060, 2002-302516 same, same 2002-305083, 2002-305084 same, same 2002-308837, and the like.

  The dopant may be dispersed throughout the layer containing the host compound or may be partially dispersed.

  Other compounds may be further added to the light emitting layer, and the added compound may be a compound represented by the general formula (1) or another organic compound or complex that emits fluorescence or phosphorescence. It may also be a compound having another function. In addition, a polymer material such as p-polyphenylene vinylene or polyfluorene may be added to the light emitting layer, and the dopant is introduced into a polymer chain, or the dopant is used as a polymer main chain. May be used.

  The light emitting layer can be formed by forming the above compound by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, an ink jet method, a transfer method, or a printing method. Although there is no special restriction | limiting in the film thickness as a light emitting layer, Usually, it selects in 5 nm-5 micrometers. Further, as described in JP-A-57-51781, this light emitting layer is prepared by dissolving the above light emitting material in a solvent together with a binder such as a resin, and then using a spin coating method or the like. It can also be formed as a thin film. There is no restriction | limiting in particular about the film thickness of the light emitting layer formed in this way, Although it can select suitably according to a condition, Usually, it is the range of 5 nm-5 micrometers.

  Taking advantage of the characteristics of the organic EL element that it is thin and can be formed on a resin substrate, a white light-emitting element is constructed considering the case of using it for a panel or other lighting device It is practically useful to do. At present, there is no single light emitting material that exhibits white light emission, and therefore, a plurality of light emitting colors are simultaneously emitted by a plurality of light emitting materials to obtain white light emission by color mixing. A combination of a plurality of emission colors may include three emission maximum wavelengths of three primary colors (blue, green, and red), or two using complementary colors such as blue and yellow, blue green and orange. The thing containing the light emission maximum wavelength may be used. As described above, these mixed colors can be emitted by using a dopant. This can be done by changing the kind and amount of dopant contained in the same light emitting layer, When the light-emitting layer is configured by stacking layers, the color tone of light emitted outside is controlled by changing the type and amount of dopant contained in each layer and causing each layer to emit light in a different color tone. You can also

《Hole transport layer》
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.

  The hole transport material has any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbenes Derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers, particularly thiophene oligomers, and the like can be given.

  As the hole transport material, those described above can be used, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ′, N′-tetraphenyl-4,4′-diaminophenyl; N, N′-diphenyl-N, N′— Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and two more described in US Pat. No. 5,061,569 Having a condensed aromatic ring of, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 are linked in a starburst type ( MTDATA) and the like.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  The hole transport layer can be formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. it can. Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-200 nm. This hole transport layer may have a single layer structure composed of one or more of the above materials.

《Electron transport layer》
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.

  Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. As long as it has a function of transferring electrons to the light-emitting layer, any material can be selected and used from among conventionally known compounds. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives Thiopyrandioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like. Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum, Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc., and the central metals of these metal complexes are In, Mg, Cu , Ca, Sn, Ga, or Pb can also be used as an electron transport material. In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and similarly to the hole injection layer and the hole transport layer, inorganic such as n-type-Si and n-type-SiC can be used. A semiconductor can also be used as an electron transport material.

  The electron transport layer can be formed by thinning the electron transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5 nm-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

<Substrate>
The organic EL device of the present invention is preferably formed on a substrate.

  The substrate (hereinafter also referred to as a substrate, substrate, support, etc.) that can be used in the organic EL device of the present invention is not particularly limited in the type of glass, plastic, etc. Although there is no restriction | limiting in particular, As a board | substrate used preferably, glass, quartz, and a transparent resin film can be mentioned, for example. A particularly preferable substrate is a resin film that can give flexibility to the organic EL element.

  Examples of the resin film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), and cellulose. Examples include films made of triacetate (TAC), cellulose acetate propionate (CAP), and the like. On the surface of the resin film, an inorganic film, an organic film, or a hybrid film of both may be formed.

  The external extraction efficiency at room temperature for light emission of the organic electroluminescence device of the present invention is preferably 1% or more, more preferably 5% or more. Here, the external extraction quantum efficiency (%) = the number of photons emitted to the outside of the organic EL element / the number of electrons sent to the organic EL element × 100.

  In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

<< Method for producing organic EL element >>
As an example of the method for producing the organic EL device of the present invention, a method for producing an organic EL device comprising an anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode will be described.

  First, a thin film made of a desired electrode material, for example, an anode material is formed on a suitable substrate by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 10 nm to 200 nm, thereby producing an anode. To do. Next, an organic compound thin film of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a hole blocking layer, which are organic EL element materials, is formed thereon.

As a method for thinning the organic compound thin film, there are a vapor deposition method and a wet process (for example, a spin coating method, a casting method, an ink jet method, a printing method) as described above. From the viewpoint of difficulty in generating pinholes, vacuum deposition, spin coating, ink jet, and printing are particularly preferable. Further, a different film forming method may be applied for each layer. When a vapor deposition method is employed for film formation, the vapor deposition conditions vary depending on the type of compound used, but generally a boat heating temperature of 50 ° C. to 450 ° C., a vacuum degree of 10 ⁻⁶ to 10 ⁻² Pa, a vapor deposition rate of 0. It is desirable to select appropriately within the range of 01 nm / second to 50 nm / second, substrate temperature −50 ° C. to 300 ° C., film thickness 0.1 nm to 5 μm, preferably 5 nm to 200 nm.

  After these layers are formed, a thin film made of a cathode material is formed thereon by a method such as vapor deposition or sputtering so as to have a thickness of 1 μm or less, preferably in the range of 50 to 200 nm, and a cathode is provided. Thus, a desired organic EL element can be obtained. The organic EL element is preferably produced from the hole injection layer to the cathode consistently by a single evacuation, but may be taken out halfway and subjected to different film forming methods. At that time, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

  The multi-color display device of the present invention is provided with a shadow mask only at the time of forming a light emitting layer, and other layers are common, so patterning such as a shadow mask is unnecessary, and vapor deposition, casting, spin coating, inkjet A film can be formed by a method or a printing method.

  When patterning is performed only on the light-emitting layer, the method is not limited, but a vapor deposition method, an inkjet method, and a printing method are preferable. In the case of using a vapor deposition method, patterning using a shadow mask is preferable.

  In addition, it is also possible to reverse the production order and produce the cathode, the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order. When a DC voltage is applied to the multicolor display device thus obtained, light emission can be observed by applying a voltage of about 2 to 40 V with the positive polarity of the anode and the negative polarity of the cathode. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

  The display device of the present invention can be used as a display device, a display, and various light emission sources. In a display device or a display, full-color display is possible by using three types of organic EL elements of blue, red, and green light emission.

  Examples of the display device and display include a television, a personal computer, a mobile device, an AV device, a character broadcast display, and an information display in an automobile. In particular, it may be used as a display device for reproducing still images and moving images, and the driving method when used as a display device for reproducing moving images may be either a simple matrix (passive matrix) method or an active matrix method.

  Illumination devices include home lighting, interior lighting, clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. However, it is not limited to these. Moreover, you may use as an organic EL element which gave the organic EL element of this invention the resonator structure.

  Examples of the purpose of use of the organic EL element having such a resonator structure include a light source of an optical storage medium, a light source of an electrophotographic copying machine, a light source of an optical communication processing machine, and a light source of an optical sensor. It is not limited. Moreover, you may use for the said use by making a laser oscillation.

  The organic EL material of the present invention can be applied to an organic EL element that emits substantially white light as a lighting device. A plurality of light emitting colors are simultaneously emitted by a plurality of light emitting materials to obtain white light emission by color mixing. As a combination of a plurality of luminescent colors, those containing three luminescence maximum wavelengths of three primary colors of blue, green, and blue may be used. The thing containing the light emission maximum wavelength may be used.

  In addition, a combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or fluorescent materials that emit light, and a light emitting material that emits fluorescence or phosphorescence, and light from the light emitting material. Any combination with a dye material that emits light as excitation light may be used. However, in the white organic electroluminescence device according to the present invention, it is only necessary to mix and combine a plurality of light-emitting dopants. It is only necessary to provide a mask only when forming a light emitting layer, a hole transport layer, an electron transport layer, or the like, and simply arrange them separately by the mask. Since other layers are common, patterning of the mask or the like is not necessary. In addition, for example, an electrode film can be formed by a vapor deposition method, a cast method, a spin coating method, an ink jet method, a printing method, or the like, and productivity is also improved. According to this method, unlike a white organic EL device in which light emitting elements of a plurality of colors are arranged in parallel in an array, the elements themselves are luminescent white.

  There is no restriction | limiting in particular as a luminescent material used for a light emitting layer, For example, if it is a backlight in a liquid crystal display element, an ortho metalated complex (Ir complex, so that it may suit the wavelength range corresponding to CF (color filter) characteristic) Pt complex etc.) or any known light emitting material may be selected and combined to whiten.

  As described above, the white light-emitting organic EL device according to the present invention is a kind of lamp such as a home lighting, an interior lighting, or an exposure light source as various light emitting light sources and lighting devices in addition to the display device and the display. It is also useful for display devices such as backlights for liquid crystal display devices.

  Others such as backlights for watches, signboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. There are a wide range of uses such as household appliances.

<Display device>
The organic EL element of the present invention may be used as one kind of lamp for illumination or exposure light source, a projection device for projecting an image, or a display for directly viewing a still image or a moving image. It may be used as a device (display). When used as a display device for reproducing moving images, the driving method may be either a simple matrix (passive matrix) method or an active matrix method. Alternatively, a full-color display device can be manufactured by using three or more organic EL elements of the present invention having different emission colors. Alternatively, it is possible to make a single color emission color, for example, white emission, into BGR using a color filter to achieve full color. Furthermore, it is possible to convert the emission color of the organic EL to another color by using a color conversion filter, and in this case, λmax of the organic EL emission is preferably 480 nm or less.

  An example of a display device composed of the organic EL element of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram illustrating an example of a display device including organic EL elements. It is a schematic diagram of a display such as a mobile phone that displays image information by light emission of an organic EL element.

  The display 1 includes a display unit A having a plurality of pixels, a control unit B that performs image scanning of the display unit A based on image information, and the like.

  The control unit B is electrically connected to the display unit A, and sends a scanning signal and an image data signal to each of the plurality of pixels based on image information from the outside. The pixels for each scanning line are converted into image data signals by the scanning signal. In response to this, light is sequentially emitted and image scanning is performed to display image information on the display unit A.

  FIG. 2 is a schematic diagram of the display unit A.

  The display unit A includes a wiring unit including a plurality of scanning lines 5 and data lines 6, a plurality of pixels 3 and the like on a substrate. The main members of the display unit A will be described below. FIG. 2 shows a case where the light emitted from the pixel 3 is extracted in the direction of the white arrow (downward).

  The scanning lines 5 and the plurality of data lines 6 in the wiring portion are each made of a conductive material, and the scanning lines 5 and the data lines 6 are orthogonal to each other in a grid pattern and are connected to the pixels 3 at orthogonal positions (details are shown in FIG. Not shown).

  When a scanning signal is applied from the scanning line 5, the pixel 3 receives an image data signal from the data line 6 and emits light according to the received image data. Full color display is possible by appropriately arranging pixels in the red region, the green region, and the blue region that emit light on the same substrate.

  Next, the light emission process of the pixel will be described.

  FIG. 3 is a schematic diagram of a pixel.

  The pixel includes an organic EL element 10, a switching transistor 11, a driving transistor 12, a capacitor 13, and the like. A full color display can be performed by using red, green, and blue light emitting organic EL elements as the organic EL elements 10 in a plurality of pixels, and juxtaposing them on the same substrate.

  In FIG. 3, an image data signal is applied from the control unit B to the drain of the switching transistor 11 through the data line 6. When a scanning signal is applied from the control unit B to the gate of the switching transistor 11 via the scanning line 5, the driving of the switching transistor 11 is turned on, and the image data signal applied to the drain is supplied to the capacitor 13 and the driving transistor 12. Is transmitted to the gate.

  By transmitting the image data signal, the capacitor 13 is charged according to the potential of the image data signal, and the drive of the drive transistor 12 is turned on. The drive transistor 12 has a drain connected to the power supply line 7 and a source connected to the electrode of the organic EL element 10, and the power supply line 7 connects to the organic EL element 10 according to the potential of the image data signal applied to the gate. Current is supplied.

  When the scanning signal is moved to the next scanning line 5 by the sequential scanning of the control unit B, the driving of the switching transistor 11 is turned off. However, even if the driving of the switching transistor 11 is turned off, the capacitor 13 maintains the potential of the charged image data signal, so that the driving of the driving transistor 12 is kept on and the next scanning signal is applied. Until then, the light emission of the organic EL element 10 continues. When the scanning signal is next applied by sequential scanning, the driving transistor 12 is driven according to the potential of the next image data signal synchronized with the scanning signal, and the organic EL element 10 emits light.

  That is, the organic EL element 10 emits light by the switching transistor 11 and the drive transistor 12 that are active elements for the organic EL element 10 of each of the plurality of pixels, and the light emission of the organic EL element 10 of each of the plurality of pixels 3. It is carried out. Such a light emitting method is called an active matrix method.

  Here, the light emission of the organic EL element 10 may be light emission of a plurality of gradations by a multi-value image data signal having a plurality of gradation potentials, or on / off of a predetermined light emission amount by a binary image data signal. But you can.

  The potential of the capacitor 13 may be held continuously until the next scanning signal is applied, or may be discharged immediately before the next scanning signal is applied.

  In the present invention, not only the active matrix method described above, but also a passive matrix light emission drive in which the organic EL element emits light according to the data signal only when the scanning signal is scanned.

  FIG. 4 is a schematic view of a passive matrix display device. In FIG. 4, a plurality of scanning lines 5 and a plurality of image data lines 6 are provided in a lattice shape so as to face each other with the pixel 3 interposed therebetween.

  When the scanning signal of the scanning line 5 is applied by sequential scanning, the pixels 3 connected to the applied scanning line 5 emit light according to the image data signal. In the passive matrix system, the pixel 3 has no active element, and the manufacturing cost can be reduced.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

Example 1
<Production of organic EL element>
An organic EL element was produced as follows.

  After patterning on a substrate (NH-Techno Glass NA-45) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes.

This transparent support substrate was fixed to a substrate holder of a commercially available vacuum evaporation apparatus, while 200 mg of α-NPD was put in a molybdenum resistance heating boat, and 200 mg of the compound 74 of the present invention was put in another molybdenum resistance heating boat. 200 mg of CBP is placed in a molybdenum resistance heating boat, 100 mg of phosphorescent compound Ir (ppy) ₃ is placed in another molybdenum resistance heating boat, and 200 mg of Alq ₃ is placed in another resistance heating boat made of molybdenum. Installed on.

Next, the pressure in the vacuum chamber was reduced to 4 × 10 ⁻⁴ Pa, and the heating boat containing α-NPD was energized and heated, and deposited on the transparent support substrate at a deposition rate of 0.1 nm / sec. The hole transport layer was provided. Further, the heating boat containing the CBP of the present invention and the phosphorescent compound Ir (ppy) ₃ is energized and heated, and deposited on the hole transport layer at a deposition rate of 0.2 nm / sec and 0.013 nm / sec, respectively. Co-evaporated to provide a light emitting layer having a thickness of 35 nm. In addition, the substrate temperature at the time of vapor deposition was room temperature. Furthermore, it supplied with electricity to the said heating boat containing the compound 74, it heated, and it vapor-deposited on the said light emitting layer with the vapor deposition rate of Table 1, and provided the 10-nm-thick hole blocking layer. Further, the heating boat containing Alq ₃ is further energized and heated, and further deposited on the hole blocking layer at a deposition rate of 0.1 nm / sec to provide an electron transport layer having a thickness of 40 nm. It was. In addition, the substrate temperature at the time of vapor deposition was room temperature.

  Then, 0.5 nm of lithium fluoride and 110 nm of aluminum were vapor-deposited, the cathode was formed, and the organic EL element OLED1-1 was produced. Other organic EL elements shown in Table 1 were similarly formed in the organic EL element OLED1 except that the heating temperature was changed so that the vapor deposition rate of the compound 74 was set to the vapor deposition rate shown in Table 1 in the formation of the hole blocking layer. -2 to 1-9 were produced.

  In addition, the film thickness provided the sensor (crystal oscillator) provided in a vapor deposition tank, and performed it using ULVAC CRTM-9000. In addition, a film thickness meter previously calibrated by actual film thickness measurement was used.

About the organic EL element OLED1-1~1- 9, temperature 23 ° C., 2.5 mA under a dry nitrogen atmosphere / cm ² of light emission luminance upon applying a constant current (cd ^{/ m} 2), the external quantum efficiency It was measured. The external quantum efficiency was expressed as a relative value when the organic EL element OLED1-1 was set to 100. Luminance and external quantum efficiency were measured using a spectral radiance meter CS-1000 (Minolta).

  It can be seen that, in the sample prepared by manually changing the vapor deposition rate of the compound according to the present invention as the hole blocking layer, the light emission efficiency of the sample having a high vapor deposition rate is good.

Example 2
The organic EL elements OLED2-1 to 2-9 were produced in the same manner except that the compound 74 in Example 1 was changed to the compound 189 and the vapor deposition rates shown in Table 2 were used.

For the organic EL elements OLED2-1 to 2-9, the light emission luminance (cd / m ² ) and the external quantum efficiency were measured in the same manner as in Example 1 at a temperature of 23 ° C. and in a dry nitrogen gas atmosphere. As in Example 1, the external quantum efficiency measurement results are shown in Table 2 as relative values when the organic EL element OLED2-1 is 100.

It can be seen that even in the above samples prepared by changing the vapor deposition rate by changing the compound according to the present invention, the luminous efficiency of the sample with a high vapor deposition rate is good.

  In addition, the same effects were obtained with compounds 7, 8, 9, 24, 36, 60, 72, 73, 118, and 193.

Example 3
The CBP of Example 1 was changed to Compound 74, and the vapor deposition rates of Ir (ppy) ₃ and Compound 74 were respectively co-deposited as shown in the following table, and the vapor deposition rate of the hole blocking layer was 1.5 nm / s. Organic EL elements OLED3-1 to 3-9 similar to those described above were prepared except that they were fixed to each other.

  In the co-evaporation, each deposition rate was determined by independently installing a sensor at a position where they did not interfere with each other.

For the organic EL elements OLED3-1 to 3-9, the light emission luminance (cd / m ² ) and the external quantum efficiency were measured in the same manner as in Example 1 at a temperature of 23 ° C. and in a dry nitrogen gas atmosphere. The measurement results of external quantum efficiency are shown in Table 3 below as in Example 1.

  From Table 3, it can be seen that even when the compound according to the present invention is co-evaporated with a phosphorescent dopant as the light emitting layer, the luminous efficiency of the sample having a high deposition rate is good when the co-evaporation rate is changed.

Example 4
In Example 3, the electron transport material Alq ₃ was changed to change the compound 74 and cesium co-deposited film to 150 nm, and an organic EL device was produced with the same configuration except that the LiF layer was omitted. At that time, OLEDs 4-1 to 4-9 were obtained by changing the co-deposition rate of compound 74 and cesium as shown in Table 4.

Here, the voltage when a constant current of ^2.5 mA / cm ² is passed is measured, and the relative value is shown when the value of OLED4-1 is 100 (the smaller the better).

From Table 4, it can be seen that even when the compound according to the present invention is co-evaporated with cesium as an electron transport layer in place of Alq ₃ , a sample with a high deposition rate can lower the driving voltage when the co-evaporation rate is changed. .

It is the schematic diagram which showed an example of the display apparatus comprised from an organic EL element. It is a schematic diagram of a display part. It is a schematic diagram of a pixel. It is a schematic diagram of a passive matrix type full-color display device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Display 3 Pixel 5 Scan line 6 Data line 7 Power supply line 10 Organic EL element 11 Switching transistor 12 Drive transistor 13 Capacitor A Display part B Control part

Claims (1)

An organic EL device having a hole blocking layer formed by vapor-depositing at least one compound represented by the following general formula (3) or general formula (4) at a deposition rate of 0.5 nm / s or more .

[Wherein R _{601 to} R ₆₀₆ are each represented by a hydrogen atom, or the following general formula (1-3), (1-5), (1-6), (1-9) or (1-10) 2 or 3 of R _{601 to} R ₆₀₆ are the general formulas (1-3), (1-5), (1-6), (1-9) or (1- The group represented by 10) is represented. However, two or three groups represented by the general formula (1-3), (1-5), (1-6), (1-9) or (1-10) are not adjacent. ]

[Wherein R _{611 to} R ₆₂₀ represent a hydrogen atom, an alkyl group, an aryl group, a halogen atom, a group in which adjacent groups are bonded to form a benzene ring, or the following general formulas (1-3), (1 -5), (1-6), (1-9) or a group represented by (1-10), two or four of R _{611 to} R ₆₂₀ are represented by the general formula (1- 3) represents a group represented by (1-5), (1-6), (1-9) or (1-10). However, when there are two groups represented by formulas (1-3), (1-5), (1-6), (1-9) or (1-10), R ₆₁₃ and R ₆₁₈ are General
A group represented by formula (1-3), (1-5), (1-6), (1-9) or (1-10) is represented, and the general formula (1-3), (1- 5), (1-6), (1-9) or when the number of groups represented by (1-10) is four, R ₆₁₂ , R ₆₁₄ , R ₆₁₇ and R ₆₁₉ are represented by the general formula (1-3) , (1-5), (1-6), (1-9) or a group represented by (1-10). ]

[Wherein, R _{522 to} R ₅₂₇ each independently represents a hydrogen atom, an alkyl group or an aryl group. ]

[Wherein, R _{542 to} R ₅₄₈ each independently represents a hydrogen atom, an alkyl group or an aryl group. ]

[Wherein, R _{552 to} R ₅₅₈ each independently represents a hydrogen atom, an alkyl group or an aryl group. ]

[Wherein, R represents a hydrogen atom, an alkyl group or an aryl group. The plurality of R may be the same or different. ]

[Wherein, R represents a hydrogen atom, an alkyl group or an aryl group. The plurality of R may be the same or different. ]

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