Light emitting materials

Abstract

To provide: a novel organometallic complex; light emitting elements, light emitting devices and electronic apparatuses which include the organometallic complex; a composition in which the organometallic complex is dissolved; and a method for manufacturing light emitting elements using the composition.SOLUTION: An organometallic complex represented by general formula (G1) is provided. The organometallic complex has high solubility in a solvent, and high light emission efficiency, and thus can be used suitably for manufacturing a light emitting element. The light emitting element manufactured using the organometallic complex can achieve high light emission efficiency.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to organometallic complexes and compositions containing organometallic complexes. The present invention relates to a light-emitting element, a light-emitting device, an electronic device, and a method for manufacturing a light-emitting element using luminescence. do. [Background technology]

[0002] Organic compounds become excited by absorbing light. This can cause various reactions (photochemical reactions) or luminescence. There are various cases and applications.

[0003] One example of a photochemical reaction is the reaction of singlet oxygen with an unsaturated organic molecule (oxygen addition). For example, see Non-Patent Document 1. The ground state of oxygen molecules is a triplet state, so Singlet oxygen is not produced by direct photoexcitation. However, other triplet excited species are In the presence of the molecule, singlet oxygen is generated, which can lead to an oxygen addition reaction. Compounds that can become triplet excited molecules are called photosensitizers.

[0004] Thus, to generate singlet oxygen, a triplet excited molecule can be excited by light. A photosensitizer is required. However, the ground state of most organic compounds is a singlet state. Therefore, photoexcitation to the triplet excited state is a forbidden transition, and triplet excited molecules are unlikely to be generated. Therefore, such photosensitizers are required to have intersystem crossing from the singlet excited state to the triplet excited state. Compounds that are prone to photoexcitation to the triplet excited state (or compounds that are prone to photoexcitation to the triplet excited state, which is a forbidden transition) In other words, such compounds are required as photosensitizers. It is possible and beneficial to use

[0005] Such compounds often also emit phosphorescence. This is the emission caused by the transition between two energies. In normal organic compounds, the triplet This refers to the emission that occurs when an electron returns from an excited state to the singlet ground state (as opposed to the singlet excited The emission of light when the electron goes from the excited state to the singlet ground state is called fluorescence. Compounds capable of converting the triplet excited state into light emission (hereinafter referred to as phosphorescent compounds) An example of an application field is a light-emitting element that uses an organic compound as a light-emitting substance.

[0006] The structure of this light-emitting element is simply a light-emitting layer containing an organic compound, which is a light-emitting substance, provided between electrodes. Its simple structure and characteristics such as thin, lightweight, high-speed response, and low DC voltage operation make it the next-generation It is attracting attention as a flat panel display element. The display also features excellent contrast and image quality, as well as a wide viewing angle.

[0007] The light-emitting mechanism of a light-emitting element that uses an organic compound as a light-emitting substance is a carrier injection type. That is, by applying a voltage to a light-emitting layer sandwiched between electrodes, electrons injected from the electrodes When the holes recombine and the luminescent material becomes excited, the excited state returns to the ground state. It emits light. As for the types of excited states, as in the case of photoexcitation mentioned earlier, there are singlet excited states (S * ) and triplet excited states (T * ) is possible. In addition, the statistical generation of the light emitting element The ratio is S * :T * It is believed that the ratio is 1:3.

[0008] Compounds that convert the singlet excited state into luminescence (hereafter referred to as fluorescent compounds) are No emission from the triplet excited state (phosphorescence) was observed, but emission from the singlet excited state (fluorescence) was observed. Therefore, the internal quantum efficiency ( The theoretical limit for the ratio of photons generated to the number of injected carriers is S * :T * =1: It is said to be 25% based on the fact that

[0009] On the other hand, if the above-mentioned phosphorescent compounds are used, the internal quantum efficiency can be theoretically increased to 75-100%. In other words, the luminous efficiency is three to four times higher than that of fluorescent compounds. For these reasons, in order to realize a highly efficient light-emitting element, a light-emitting element using a phosphorescent compound has been developed. In recent years, the development of phosphorescent compounds has been actively pursued (for example, see Non-Patent Document 2). Due to their high phosphorescence quantum yield, organometallic complexes with iridium as the central metal have attracted attention. It has been done. [Prior art documents] [Non-patent literature]

[0010] [Non-Patent Document 1] Haruo Inoue and 3 others, Basic Chemistry Course Photochemistry I (Maruzen Co., Ltd.), P106-110 [Non-Patent Document 2] Chihaya Adachi and 5 others, Applied Physics Letters, Vol. 78, No. 11, 1622-1624 (2001) Summary of the Invention [Problem to be solved by the invention]

[0011] The organometallic complexes disclosed in Non-Patent Document 2 are prone to intersystem crossing and are therefore photoinduced. It is expected that it can be used as a sensitizer. It also emits light (phosphorescence) from the triplet excited state. Since it is easy to synthesize, its application to light-emitting devices is expected to lead to highly efficient light-emitting devices. However, the number of such organometallic complexes is still limited.

[0012] In addition, the organometallic complexes described in Non-Patent Document 2 are generally prepared by vacuum deposition. However, the vacuum deposition method has a low material utilization efficiency. There are problems such as the difficulty of commercializing light-emitting devices and the limited size of the substrate. In consideration of mass production, the use of a film formation method other than the vacuum deposition method is being considered. It is being done.

[0013] Methods for depositing organic compound films on large substrates include the droplet ejection method and spin coating method. A solution of an organic compound dissolved in a solvent is used for forming such a film. do.

[0014] However, the above-mentioned organometallic complexes have low solubility and cannot be easily dissolved by droplet discharge or spin coating. However, it was not possible to obtain a solution of sufficient concentration for film formation using this method.

[0015] Therefore, an object of the present invention is to provide a novel organometallic complex.

[0016] The present invention also provides a composition in which an organometallic complex is dissolved, and a method for manufacturing a light-emitting element using the composition. The purpose is to provide

[0017] Another object of the present invention is to provide a light-emitting element, a light-emitting device, and an electronic device using an organometallic complex. do. [Means for solving the problem]

[0018] The present inventors have found that the organometallic complex represented by the general formula (G1) has high solubility in a solvent. was found.

[0019] Therefore, one aspect of the present invention is an organometallic complex represented by general formula (G1).

[0020] [ka] (In the formula, Ar represents an arylene group. R 1 is either an alkyl group or an aryl group. Represents. R 2 R represents either a hydrogen atom, an alkyl group, or an aryl group. 3 is hydrogen or an alkyl group. 2 and R 3 are bonded to each other to form an alicyclic ring. M may be a central metal and may represent either a group 9 element or a group 10 element. In addition, when the M is a group 9 element, n=2, and when the M is a group 10 element, n=1. R 21 and R 22 One of the groups is an alkyl group or a haloalkyl group having 2 to 10 carbon atoms. and the other represents an alkyl group or a haloalkyl group having 1 to 10 carbon atoms.)

[0021] Another aspect of the present invention is an organometallic complex represented by general formula (G1).

[0022] [ka]

[0023] (In the formula, Ar represents an arylene group. R 1 is either an alkyl group or an aryl group. Represents. R2 R represents either a hydrogen atom, an alkyl group, or an aryl group. 3 is hydrogen or an alkyl group. 2 and R 3 are bonded to each other to form an alicyclic ring. M may be a central metal and may represent either a Group 9 element or a Group 10 element. In addition, when the M is a group 9 element, n=2, and when the M is a group 10 element, n=1. R 21 and R 22 one of the groups is an alkyl group or a haloalkyl group having 2 to 4 carbon atoms; and the other represents an alkyl group or a haloalkyl group having 1 to 4 carbon atoms.

[0024] Another aspect of the present invention is an organometallic complex represented by general formula (G1).

[0025] [ka]

[0026] (In the formula, Ar represents an arylene group. R 1 is either an alkyl group or an aryl group. Represents. R 2 R represents either a hydrogen atom, an alkyl group, or an aryl group. 3 is hydrogen or an alkyl group. 2 and R 3 are bonded to each other to form an alicyclic ring. M may be a central metal and may represent either a Group 9 element or a Group 10 element. In addition, when the M is a group 9 element, n=2, and when the M is a group 10 element, n=1. R 21 and R 22 one of the groups represents a branched alkyl group having 3 to 4 carbon atoms, The other represents an alkyl group or a haloalkyl group having 1 to 4 carbon atoms.

[0027] Another aspect of the present invention is an organometallic complex represented by general formula (G1).

[0028] [ka]

[0029] (In the formula, Ar represents an arylene group. R 1 is either an alkyl group or an aryl group. Represents. R 2 R represents either a hydrogen atom, an alkyl group, or an aryl group. 3 is hydrogen or an alkyl group. 2 and R 3 are bonded to each other to form an alicyclic ring. M may be a central metal and may represent either a Group 9 element or a Group 10 element. In addition, when the M is a group 9 element, n=2, and when the M is a group 10 element, n=1. R 21 and R 22 Each of the groups represents a branched alkyl group having 3 to 4 carbon atoms. vinegar.)

[0030] Another aspect of the present invention is an organometallic complex represented by general formula (G2).

[0031] [ka]

[0032] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 2 is hydrogen, or an alkyl group, or a phenyl group, or a substituent In addition, R 3 is either hydrogen or an alkyl group. Note that R 2 and R 3 may be bonded to each other to form an alicyclic ring. 4 ~R 7 teeth, respectively hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or It represents either an alkoxy group or an alkoxycarbonyl group. M is the central metal. and represents either a Group 9 element or a Group 10 element. When M is a group 10 element, n=2, and when M is a group 10 element, n=1. 21 and R 22 One One is an alkyl group or haloalkyl group having 2 to 10 carbon atoms, and the other is an alkyl group having 1 to 10 carbon atoms. represents an alkyl group or a haloalkyl group.

[0033] Another aspect of the present invention is an organometallic complex represented by general formula (G2).

[0034] [ka]

[0035] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 2 is hydrogen, or an alkyl group, or a phenyl group, or a substituent In addition, R 3 is either hydrogen or an alkyl group. Note that R 2 and R 3 may be bonded to each other to form an alicyclic ring. 4 ~R 7 teeth, respectively hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or It represents either an alkoxy group or an alkoxycarbonyl group. M is the central metal. and represents either a Group 9 element or a Group 10 element. When M is a group 10 element, n=2, and when M is a group 10 element, n=1. 21 and R 22 One One represents an alkyl group or a haloalkyl group having 2 to 4 carbon atoms, and the other represents a represents an alkyl group or a haloalkyl group.

[0036] Another aspect of the present invention is an organometallic complex represented by general formula (G2).

[0037] [ka]

[0038] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 2 is hydrogen, or an alkyl group, or a phenyl group, or a substituent In addition, R 3 is either hydrogen or an alkyl group. Note that R 2 and R 3 may be bonded to each other to form an alicyclic ring. 4 ~R 7 teeth, respectively hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or It represents either an alkoxy group or an alkoxycarbonyl group. M is the central metal. and represents either a Group 9 element or a Group 10 element. When M is a group 10 element, n=2, and when M is a group 10 element, n=1. 21 and R 22 One One represents a branched alkyl group having 3 to 4 carbon atoms, and the other represents an alkyl group having 1 to 4 carbon atoms. represents a group or a haloalkyl group.

[0039] Another aspect of the present invention is an organometallic complex represented by general formula (G2).

[0040] [ka]

[0041] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 2 is hydrogen, or an alkyl group, or a phenyl group, or a substituent In addition, R 3 is either hydrogen or an alkyl group. Note that R 2 and R 3 may be bonded to each other to form an alicyclic ring. 4 ~R 7 teeth, respectively hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or It represents either an alkoxy group or an alkoxycarbonyl group. M is the central metal. and represents either a Group 9 element or a Group 10 element. When M is a group 10 element, n=2, and when M is a group 10 element, n=1. 21 and R 22 teeth, Each of them represents a branched alkyl group having 3 to 4 carbon atoms.

[0042] Another aspect of the present invention is an organometallic complex represented by general formula (G3).

[0043] [ka]

[0044] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 3 represents either hydrogen or an alkyl group. 4 ~R 1 2 is hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or an alkoxy group. M is a central metal; represents either a Group 9 element or a Group 10 element. When M is a Group 9 element, n = 2, and when M is a Group 10 element, n = 1. 21 and R 22 On the other hand, an alkyl group or haloalkyl group having 2 to 10 carbon atoms, and the other an alkyl group having 1 to 10 carbon atoms represents a group or a haloalkyl group.

[0045] Another aspect of the present invention is an organometallic complex represented by general formula (G3).

[0046] [ka]

[0047] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 3 represents either hydrogen or an alkyl group. 4 ~R 1 2 is hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or an alkoxy group. M is a central metal; represents either a Group 9 element or a Group 10 element. When M is a Group 9 element, n = 2, and when M is a Group 10 element, n = 1. 21 and R 22 On the other hand, represents an alkyl group or a haloalkyl group having 2 to 4 carbon atoms, and the other represents an alkyl group or a haloalkyl group having 1 to 4 carbon atoms. represents a cyclic group or a haloalkyl group.

[0048] Another aspect of the present invention is an organometallic complex represented by general formula (G3).

[0049] [ka]

[0050] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 3 represents either hydrogen or an alkyl group. 4 ~R 1 2 is hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or an alkoxy group. M is a central metal; represents either a Group 9 element or a Group 10 element. When M is a Group 9 element, n = 2, and when M is a Group 10 element, n = 1. 21 and R 22 On the other hand, the other represents an alkyl group having 1 to 4 carbon atoms or represents a haloalkyl group.

[0051] Another aspect of the present invention is an organometallic complex represented by general formula (G3).

[0052] [ka]

[0053] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 3 represents either hydrogen or an alkyl group. 4 ~R 1 2 is hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or an alkoxy group. M is a central metal; represents either a Group 9 element or a Group 10 element. When M is a Group 9 element, n = 2, and when M is a Group 10 element, n = 1. 21 and R 22 Each It represents a branched alkyl group having 3 to 4 carbon atoms.

[0054] In the above configuration, the central metal M is preferably iridium or platinum from the viewpoint of luminous efficiency. It is preferable that there is.

[0055] The present invention also relates to a composition comprising the organometallic complex and a solvent.

[0056] In addition, when the above composition is used for manufacturing a light-emitting element, the above organometallic complex is It is preferable that the concentration of the fluoride is 0.6 g / L or more in the solvent. It is desirable for it to be dissolved at a concentration of 1 g / L or more.

[0057] In the above-mentioned structure, various solvents can be used as the solvent. Metal complexes are characterized by their solubility in organic solvents that do not have aromatic rings. It is characterized by its solubility in water and alcohol.

[0058] In addition, when the composition is used for the production of a light-emitting element, a solvent is required for film formation. Therefore, the solvent must be an organic solvent with a boiling point of 50°C or higher and 200°C or lower. is preferred.

[0059] The above structure may further include an organic semiconductor material.

[0060] In the above-mentioned composition, a binder may be further included.

[0061] The present invention also includes a light-emitting element manufactured using the above-mentioned organometallic complex. Another aspect of the present invention is a light-emitting element having the above-described organometallic complex between a pair of electrodes.

[0062] The above-mentioned organometallic complexes exhibit high luminous efficiency, and therefore are preferably used in the light-emitting layer. Therefore, one aspect of the present invention is a light-emitting device having a light-emitting layer between a pair of electrodes, the light-emitting layer having the above-mentioned organometallic complex. It is a light-emitting element.

[0063] In addition, one aspect of the present invention is a liquid crystal display device comprising the above-mentioned organometallic complex and a polymer compound between a pair of electrodes. In the above-mentioned structure, the polymer compound is an organic semiconductor The present invention is characterized by being a material.

[0064] In the above-mentioned configuration, the polymer compound is a binder. The layer containing the organometallic complex and the polymer compound further contains an organic semiconductor material. Let us assume that.

[0065] In the above-mentioned configuration, the layer containing the organometallic complex and the polymer compound is a light-emitting layer. preferable.

[0066] The hole transport layer in contact with the light emitting layer is characterized by containing a low molecular weight compound. The electron transport layer in contact with the light layer is characterized by containing a low molecular weight compound.

[0067] A light-emitting device according to the present invention is characterized by including the above-mentioned light-emitting element. The present invention is characterized by having a control circuit for controlling the emission of the light emitting element. The light-emitting device includes an image display device, a light-emitting device, or a light source (including a lighting device). In addition, the panel is equipped with connectors, such as FPC (Flexible Printed Circuit). ircuit) or TAB (Tape Automated Bonding) tape Module with a tape or TCP (Tape Carrier Package) attached This includes modules with printed wiring boards attached to the ends of TAB tape and TCP. In the light emitting device in this specification, the light emitting element is a COG (Chip On Glass) type. This also includes modules in which an IC (integrated circuit) is directly mounted by the formula.

[0068] Further, electronic devices using the light-emitting element of the present invention as a display portion are also included in the scope of the present invention. Therefore, the electronic device of the present invention has a display portion, and the display portion has the above-mentioned light-emitting element and light-emitting element. and a control circuit for controlling the light emission of the element.

[0069] The present invention also includes a method for producing a light-emitting element using the above composition. One aspect of the present invention is a method for manufacturing a semiconductor device comprising the steps of: forming a first electrode; applying the composition; and removing the solvent. and a third step of forming a second electrode. This is how to create a child.

[0070] In addition, one aspect of the present invention is a method for forming a first electrode by a first step, and a method for forming a first electrode by a vapor deposition method. a second step of forming a layer comprising the composition; and a third step of applying the composition and removing the solvent. and a fourth step of forming a second electrode. do.

[0071] In addition, one aspect of the present invention is a method for forming a first electrode by applying the composition and dissolving the composition in a solvent. a second step of removing the organic compound from the substrate; and a third step of forming a layer containing an organic compound by a deposition method. and a fourth step of forming a second electrode. do. Effect of the Invention

[0072] The organometallic complex of the present invention has high solubility in a solvent. The rate is high.

[0073] In addition, the composition of the present invention contains an organometallic complex dissolved therein, and is therefore suitable for use in the manufacture of light-emitting devices. It is possible.

[0074] Furthermore, by producing a light-emitting element using the composition of the present invention, a light-emitting element suitable for industrialization can be obtained. A child creation method can be realized.

[0075] In addition, a light-emitting element manufactured using the organometallic complex of the present invention achieves high light-emitting efficiency. It is possible.

[0076] The light-emitting device and electronic device of the present invention have a light-emitting element that can achieve high light-emitting efficiency. Therefore, power consumption is low. [Brief description of the drawings]

[0077] [Figure 1] 1A to 1C are diagrams illustrating light-emitting elements of the present invention. [Diagram 2] 1A to 1C are diagrams illustrating light-emitting elements of the present invention. [Diagram 3] 1A to 1C are diagrams illustrating light-emitting elements of the present invention. [Figure 4] 1A and 1B are diagrams illustrating a light-emitting device of the present invention. [Diagram 5] 1A and 1B are diagrams illustrating a light-emitting device of the present invention. [Figure 6] 1A to 1C are diagrams illustrating electronic devices of the present invention. [Figure 7] 1A to 1C are diagrams illustrating electronic devices of the present invention. [Figure 8] 1A and 1B are diagrams illustrating a lighting device of the present invention. [Figure 9] 1A and 1B are diagrams illustrating a lighting device of the present invention. [Figure 10] 1A to 1C illustrate a method for manufacturing a light-emitting element of the present invention. [Figure 11] 1A to 1C illustrate a method for manufacturing a light-emitting element of the present invention. [Figure 12] FIG. 1H NMR chart of bis(2,3,5-triphenylpyrazinate)(dipivaloylmethanato)iridium(III) (abbreviation: [Ir(tppr)2(dpm)]). [Figure 13] FIG. 1 shows the absorption spectrum and emission spectrum of bis(2,3,5-triphenylpyrazinato)(dipivaloylmethanato)iridium(III) (abbreviation: [Ir(tppr)2(dpm)]). [Figure 14] FIG. 13 shows an emission spectrum of the light-emitting element fabricated in Example 3. [Figure 15] FIG. 1H NMR chart of bis(2,3,5-triphenylpyrazinate)(pivaloyltrifluoroacetonate)iridium(III) (abbreviation: [Ir(tppr)2(pFac)]). [Figure 16] FIG. 1 shows the absorption spectrum and emission spectrum of bis(2,3,5-triphenylpyrazinato)(pivaloyltrifluoroacetonato)iridium(III) (abbreviation: [Ir(tppr)2(pFac)]). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0078] Hereinafter, the embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the above description, and the embodiments and details thereof are not limited to those described above without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the embodiments described below. It is not to be construed as being limited to the content.

[0079] (Embodiment 1) In this embodiment, the organometallic complex of the present invention and the composition containing the organometallic complex are explain.

[0080] In the organometallic complex of the present invention, a ligand having a pyrazine skeleton is cyclometarily bonded to a central metal. There are various types of ligands having a pyrazine skeleton. However, when the ligand is a 2-arylpyrazine derivative, the ligand has a high affinity for the central metal. The cyclometallated complexes can be cyclometallated with fluorine, and the cyclometallated complexes have high phosphorescence quantum yields. Therefore, the pyrazine-based ligand is a 2-arylpyrazine derivative. It is preferable that:

[0081] In addition to the above-mentioned ligand having a pyrazine skeleton, the organometallic complex of the present invention can also have the following ligand: The chelating ligand having a β-diketone structure represented by the general formula (L0) is also coordinated to the central metal. That is, the organometallic complex of the present invention comprises a ligand having a pyrazine skeleton and the following general It has two types of chelating ligands represented by formula (L0).

[0082] [ka]

[0083] In general formula (L0), R 21 and R 22 One of the groups is an alkyl group having 2 to 10 carbon atoms. or a haloalkyl group, and the other represents an alkyl group or a haloalkyl group having 1 to 10 carbon atoms. vinegar.

[0084] The present inventors have found that the solubility of organometallic complexes having these two types of ligands in organic solvents is as follows: Specifically, the results showed that dichloromethane, dichloroethane, and chloroform Halogen-based solvents such as fluorine, and aromatic hydrocarbon solvents such as toluene and xylene. In addition, common alcohol solvents such as methanol, ethanol, and isopropanol are also available. It was also found to be soluble in the solvent.

[0085] Therefore, one aspect of the present invention is an organometallic complex represented by general formula (G1).

[0086] [ka]

[0087] (In the formula, Ar represents an arylene group. R 1 is either an alkyl group or an aryl group. Represents. R 2 R represents either a hydrogen atom, an alkyl group, or an aryl group. 3 is hydrogen or an alkyl group. 2 and R 3 are bonded to each other to form an alicyclic ring. M may be a central metal and may represent either a Group 9 element or a Group 10 element. In addition, when the M is a group 9 element, n=2, and when the M is a group 10 element, n=1. R 21 and R 22One of the groups is an alkyl group or a haloalkyl group having 2 to 10 carbon atoms. group, and the other represents an alkyl group or a haloalkyl group having 1 to 10 carbon atoms.)

[0088] The organometallic complex represented by the general formula (G1) is a complex in which a ligand having a pyrazine skeleton is a group 9 element. It is bonded to a group 10 atom (Ni, Pd, Pt) or a group 2 atom (Co, Rh, Ir). The central metal is a Group 9 or 10 element. is bonded to a group 9 or 10 atom, achieving high luminous efficiency. It is possible.

[0089] In addition, the organometallic complex represented by the general formula (G1) has high solubility in solvents, It is possible to adjust the concentration to a level suitable for forming a layer containing an organometallic complex. The organometallic complexes represented by the general formula (G1) are reacted with dichloromethane, dichloroethane, chloroform, halogenated solvents such as toluene and aromatic hydrocarbon solvents such as xylene. In addition, common alcohol solvents such as methanol, ethanol, and isopropanol Therefore, the choice of solvents is broadened. It is also possible to laminate a layer containing an organometallic complex represented by G1) by using a wet method.

[0090] In addition, 2-phenylpyrazine derivatives, which are a type of 2-arylpyrazine derivative, are coordinated When the ligand is a metal atom, the ligand can be orthometalated to the metal center (ortho Metallation is a type of cyclometallation.) And thus, 2-phenylpyrazine Orthometal complexes in which the orthometal is ortho-metalated can achieve particularly high phosphorescence quantum yields. Therefore, a more preferred form of the ligand having a pyrazine skeleton is a 2-phenylpyrazine derivative. The following organometallic complexes of 2-phenylpyrazine derivatives are orthometalated: An example is an organometallic complex represented by the following general formula (G2).

[0091] [ka]

[0092] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 2 is hydrogen, or an alkyl group, or a phenyl group, or a substituent In addition, R 3 is either hydrogen or an alkyl group. Note that R 2 and R 3 may be bonded to each other to form an alicyclic ring. 4 ~R 7 teeth, respectively hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or It represents either an alkoxy group or an alkoxycarbonyl group. M is the central metal. and represents either a Group 9 element or a Group 10 element. When M is a group 10 element, n=2, and when M is a group 10 element, n=1. 21 and R 22 One One is an alkyl group or haloalkyl group having 2 to 10 carbon atoms, and the other is an alkyl group having 1 to 10 carbon atoms. represents an alkyl group or a haloalkyl group.

[0093] Furthermore, in the general formula (G2), R 2 By replacing , good color purity and luminous efficiency (unit: cd In other words, the 2-phenylpyrazine derivative can achieve high red emission. Among the orthometalated organometallic complexes, 2,5-diphenylpyrazine derivatives are the most popular. It is preferable that the 2,5-diphenylpyrazine derivative is an organometallic complex. The trimetalated organometallic complexes include those represented by the following general formula (G3): Can be obtained.

[0094] [ka]

[0095] (In the formula, R 1 is either an alkyl group, a phenyl group, or a phenyl group having a substituent. Also, R 3 represents either hydrogen or an alkyl group. 4 ~R 1 2 is hydrogen, or an alkyl group, or a halogen group, or a haloalkyl group, or an alkoxy group. M is a central metal; represents either a Group 9 element or a Group 10 element. When M is a Group 9 element, n = 2, and when M is a Group 10 element, n = 1. 21 and R 22 On the other hand, an alkyl group or haloalkyl group having 2 to 10 carbon atoms, and the other an alkyl group having 1 to 10 carbon atoms represents a group or a haloalkyl group.

[0096] In the above-mentioned structure, the arylene group Ar is an arylene group having 6 to 25 carbon atoms. It is preferable to use substituted or unsubstituted 1,2-phenylene groups, 8,9 -Juloridine group, 1,2-naphthylene group, 2,3-naphthylene group, spirofluorene -2,3-diyl group, 9,9- such as 9,9-dimethylfluorene-2,3-diyl group Dialkylfluorene-2,3-diyl groups and the like can be used. In particular, arylene By making the group Ar a substituted or unsubstituted 1,2-phenylene group, the molecular weight can be increased. Since the increase in evaporation temperature can be suppressed, it is useful when evaporating organometallic complexes for the purpose of sublimation purification, etc. In the case where the 1,2-phenylene group has a substituent, the substituent may be more specifically Specifically, alkyl groups such as methyl, ethyl, isopropyl, and tert-butyl groups; Alkoxy groups such as methoxy, ethoxy, isopropoxy, and tert-butoxy groups; aryl groups such as phenyl and 4-biphenylyl groups, halogen groups such as fluoro groups, Haloalkyl groups such as trifluoromethyl groups, methoxycarbonyl groups, ethoxycarbonyl groups alkoxycarbonyl group, isopropoxycarbonyl group, tert-butoxycarbonyl group, etc. Among the specific examples of the arylene group Ar, particularly preferred are free radicals. It is a substituted 1,2-phenylene group.

[0097] In the above-mentioned structure, the aryl group is a substituted or unsubstituted phenyl group, 1-naphthyl group, 2-naphthyl group, spirofluoren-2-yl group, 9,9-dimethylfluorenyl group Examples of such a group include a 9,9-dialkylfluoren-2-yl group such as a fluoren-2-yl group. In addition, when taking into consideration the solubility in a solvent, an aryl group having 6 to 25 carbon atoms is preferable. In the case where the aryl group has a substituent, the substituent is preferably methyl. alkyl groups such as ethyl, isopropyl, and tert-butyl groups, and methoxy and ethoxy groups. alkoxy groups such as butoxy, isopropoxy, and tert-butoxy; phenyl groups; Aryl groups such as 4-biphenylyl groups, halogen groups such as fluoro groups, and trifluoromethyl groups haloalkyl groups such as methoxycarbonyl, ethoxycarbonyl, isopropanol, etc. Examples of the alkoxycarbonyl group include an alkoxycarbonyl group such as an alkoxycarbonyl group and a tert-butoxycarbonyl group. can be done.

[0098] In the above-mentioned structure, the substituent of the phenyl group having a substituent is a methyl group. , ethyl, isopropyl, tert-butyl, and other alkyl groups; methoxy, ethoxy, and Alkoxy groups such as oxy, isopropoxy, and tert-butoxy groups, phenyl groups, 4 -Aryl groups such as biphenylyl groups, halogen groups such as fluoro groups, and trifluoromethyl groups haloalkyl groups such as methoxycarbonyl, ethoxycarbonyl, isopropoxy, etc. Examples of the alkoxycarbonyl group include a tert-butoxycarbonyl group and an alkoxycarbonyl group. can be.

[0099] In the above-mentioned structure, the alkyl group is a methyl group, an ethyl group, an isopropyl group, Examples of the alkyl group include an aryl group, a tert-butyl group, a cyclohexyl group, and a pentyl group. In addition, in the above-mentioned organometallic complexes, taking into consideration the solubility in the solvent, However, the above-mentioned organometallic complexes are preferably alkyl groups having 4 or less carbon atoms. In other words, the above-mentioned organometallic complex has the characteristic of being highly soluble even if it has an alkyl group. In the above, the alkyl group is a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, etc. One of the features of the organometallic complex of the present invention is that the alkyl group has 4 or less carbon atoms. do.

[0100] In the above-mentioned structure, examples of the halogen group include a fluoro group and a chloro group. From the viewpoint of chemical stability, a fluoro group is preferred. The trifluoromethyl group is preferred.

[0101] In the above-mentioned structure, the alkoxy group is a methoxy group, an ethoxy group, an isopropyl group, The above-mentioned organometallic complexes have a carbon number of Even if the alkoxy group is less than 4, it has the characteristic of being highly soluble. In the organometallic complex, the alkoxy group is a methoxy group, an ethoxy group, an isopropoxy group, The organic solvent of the present invention is preferably an alkoxy group having 4 or less carbon atoms, such as a tert-butoxy group. This is one of the characteristics of metal complexes.

[0102] In the above-mentioned structure, the alkoxycarbonyl group is a methoxycarbonyl group. , ethoxycarbonyl group, isopropoxycarbonyl group, tert-butoxycarbonyl The above-mentioned organometallic complexes include alkoxycarbonyl groups having 5 or less carbon atoms. Even the alkoxycarbonyl group has the characteristic of being highly soluble. In the above-mentioned organometallic complex, the alkoxycarbonyl group is a methoxycarbonyl group, an ethoxycarbonyl group, Carbonyl group, isopropoxycarbonyl group, tert-butoxycarbonyl group, etc. The alkoxycarbonyl group having a prime number of 5 or less is also a feature of the organometallic complex of the present invention. There is one.

[0103] In the above general formula (L0) and general formulas (G1) to (G3), R 21 Oh BiR 22 One of the groups is an alkyl group or a haloalkyl group having 2 to 10 carbon atoms, and the other is A ligand represented by general formula (L0) and a haloalkyl group having 1 to 10 carbon atoms. Examples of the ligands include those represented by (L1) to (L10). That is, R 2 1 and R 22 If either one of the carbon atoms is 2 or more, the organometallic complex of the present invention is sufficiently The present inventors have found that it is possible to exhibit sufficient solubility.

[0104] [ka]

[0105] R 21 and R 22 The larger the carbon number of the alkane, the higher the solubility. The organometallic complexes described above are 21 and R 22 is an alkyl group or halo group having 4 or less carbon atoms. In other words, the above-mentioned organometallic complex has the characteristic of being highly soluble even if it has an alkyl group. In R 21 and R 22 However, methyl, ethyl, isopropyl, and tert-butyl groups alkyl groups having 4 or less carbon atoms, such as ethyl groups, or trifluoromethyl groups having 4 or less carbon atoms. The fact that the organometallic complex of the present invention has the haloalkyl group shown below is also one of its characteristics.

[0106] Therefore, in the above general formula (L0) and general formulas (G1) to (G3), R 21 and R 22 one of the groups represents an alkyl group or a haloalkyl group having 2 to 4 carbon atoms, and the other Each of the groups preferably represents an alkyl group or a haloalkyl group having 1 to 4 carbon atoms.

[0107] The feature of high solubility even without a long-chain alkyl group is that the organometallic complex of the present invention is produced. When applied to an optical element, the present invention has the effect of not impeding the movement of carriers. When the organometallic complex of the present invention is used as a light-emitting substance of a light-emitting element, This has the effect of not impeding the injection of carriers.

[0108] In particular, R 21 and R 22 is a branched alkyl group, This is preferred because it increases solubility.

[0109] Therefore, in the above general formula (L0) and general formulas (G1) to (G3), R 21 and R 22 One of them represents a branched alkyl group having 3 to 4 carbon atoms, and the other represents a It is preferable that the group represents an alkyl group or a haloalkyl group having 1 to 4 prime numbers.

[0110] In addition, R 21 and R 22 When both are branched alkyl groups, the solubility is improved. This is preferred because it increases the dissolvability.

[0111] Therefore, in the above general formula (L0) and general formulas (G1) to (G3), R 21 and R 22 Each of the alkyl groups preferably represents a branched alkyl group having 3 to 4 carbon atoms. I wish.

[0112] In addition, in the general formulas (G1) to (G3), from the viewpoint of ease of synthesis, R 3 Water It is preferable that R 3 When is hydrogen, the steric hindrance of the ligand is small, so the metal This is preferable from the viewpoint of synthesis yield because it is easy to bind to on.

[0113] In addition, the central metal M of the above-mentioned organometallic complex is preferably iridium or tungsten from the viewpoint of the heavy atom effect. In particular, iridium is very suitable because of its remarkable heavy atom effect. This is preferred because it is highly efficient and chemically stable.

[0114] Specific examples of the organometallic complexes include those represented by the following structural formulas (101) to (178): However, the present invention is not limited thereto.

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[0139] As a method for synthesizing the organometallic complex of the present invention, various reactions can be applied. For example, The organometallic complex derivative of the present invention can be synthesized by carrying out the synthesis reaction shown below. The method for synthesizing the organometallic complex derivative of the present invention is not limited to the following synthesis method. stomach.

[0140] <<Method for synthesizing pyrazine derivative represented by general formula (G0)>> The organometallic complex of the present invention is a pyrazine derivative represented by the following general formula (G0): orthometallation to group 10 metal ions to form organometallic complexes is doing.

[0141] [ka]

[0142] The pyrazine derivative represented by the general formula (G0) can be synthesized by the following simple synthesis scheme: For example, as shown in the following scheme (a), ) is lithiated with an alkyl lithium or the like and reacted with pyrazine (A2) to obtain Alternatively, as shown in the following scheme (a1), a boronic acid (A1-1 It can be obtained by coupling the pyrazine halide (A2-1) with the pyrazine halide (A2-2). Alternatively, as shown in the following scheme (a2), a diketone (A1-2) of an arene and a diketone (A2-3) of an aryl group can be prepared. Alternatively, it can be obtained by reacting an amine (A2-2) according to the following scheme (a As shown in 3), the pyrazine of the arene (A1-3) and the lithio or Grignard It can also be obtained by reacting with reagent (A2-3). In the formula, X is a halogen atom. Represents the element .

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[0147] The above-mentioned compounds (A1), (A2), (A1-1), (A2-1), (A1-2), (A 2-2), (A1-3), and (A2-3) are available in various types on the market or in combination. Since it is possible to synthesize many types of pyrazine derivatives represented by general formula (G0), Therefore, the organometallic complex of the present invention has a wide variety of ligands. It has the characteristic of being wealth.

[0148] <<Method for synthesizing the organometallic complex of the present invention represented by general formula (G1)>> Next, the pyrazine derivative represented by the general formula (G0) is ortho-metallated to form the compound of the present invention. We will explain the synthesis of the organometallic complex represented by the general formula (G1). Reveal.

[0149] First, as shown in the following synthesis scheme (b), a pyrazine derivative represented by the general formula (G0) is prepared. The body and halogen-containing metal compounds of Group 9 or 10 metals (metal halides and metal complexes) The binuclear complex (B) can be obtained by heating the mixture of the above in a suitable solvent. The following are examples of the solvents: water, alcohols (glycerol, ethylene glycol, 2-ethoxyethanol) (ethanol, 2-methoxyethanol, etc.), ethers (dioxane, anisole, etc.), etc. They can be used alone or in combination of two or more. Group metal compounds include rhodium chloride hydrate, palladium chloride, and iridium chloride hydrate. , iridium chloride hydrate hydrochloride, potassium tetrachloroplatinate (II), etc. However, the present invention is not limited to these. In the scheme (b), M is a group 9 element or X represents a halogen element. When M is a group 9 element, n=2, and when M is a group 10 element, n=2. For group elements, n=1.

[0150] [ka]

[0151] Furthermore, as shown in the following synthesis scheme (c), a dinuclear complex (B) and a β-diketone structure having The ligand (L0) is heated in a suitable solvent in the presence of a base to give a compound of the general formula (G The organometallic complex of the present invention having the structure represented by 1) can be obtained. , alcohols (glycerol, ethylene glycol, 2-ethoxyethanol, 2-methyl ethers (dioxane, anisole, etc.), either alone or Two or more types can be used in combination. In scheme (c), M is an element of group 9 or less. or a group 10 element, and X represents a halogen element. Also, when M is a group 9 element, n=2, and M is For group 10 elements, n=1.

[0152] [ka]

[0153] Additionally, compositions containing the organometallic complexes of the present invention are also included in the scope of the present invention. The composition of the present invention is a composition containing the above-mentioned organometallic complex and a solvent.

[0154] In the above-mentioned composition, various solvents can be used as the solvent. Aromatic rings (e.g., benzene ring) such as benzene, xylene, and methoxybenzene (anisole) The above-mentioned organometallic complexes can be dissolved in a solvent having dimethyl sulfoxide. Dimethyl sulfoxide (DMSO), dimethylformamide (DMF), chloroform, etc. It is possible for the material to be dissolved in an organic solvent that does not contain a fluorine atom.

[0155] In particular, the above-mentioned organometallic complexes can be used in ethers such as diethyl ether and dioxane, , methanol, ethanol, isopropanol, butanol, 2-methoxyethanol, It can also be dissolved in alcohols such as 2-ethoxyethanol. When a composition using alcohol as a solvent is used in the manufacture of a light-emitting device, the EL layer of the light-emitting device is laminated. This has a great effect in that it is possible to form a layer using a deposition method or the like. On the layer containing the organic compound, a further layer is formed using a composition using alcohol as a solvent. can be formed.

[0156] In addition, when the composition is used for manufacturing a light-emitting element, the organometallic complex is preferably a solvent. It is preferable that the concentration of the compound dissolved in the solvent is 0.6 g / L or more. More preferably, it is 0. It is desirable for it to be dissolved at a concentration of 9g / L or more.

[0157] In addition, when the above composition is used for manufacturing a light emitting element, the composition is required to form a film. Since the solvent needs to be removed, the solvent is an organic solvent with a boiling point of 50°C or higher and 200°C or lower. It is preferable that

[0158] In addition, when the composition described in this embodiment mode is used for manufacturing a light-emitting element, It is preferable that the organic semiconductor material is contained in the organic semiconductor material. In particular, organic semiconductor materials and For the deposition, low molecular weight compounds and high molecular weight compounds can be used, but the quality of the deposited film may be poor. In particular, it is preferable to use a high molecular weight compound. A low molecular weight compound (also called a medium molecular weight compound) that has a substituent that increases solubility in the solvent. It is preferable to use:

[0159] Specific examples of organic semiconductor materials are listed below. For example, organic semiconductor materials with hole transport properties Examples of the compound include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl ( Abbreviation: NPB), 4,4'-bis[N-(9-phenanthryl)-N-phenylamino] Biphenyl (abbreviation: PPB), 4,4'-bis[N-(3-methylphenyl)-N-phenyl N-(9,9-dimethylphenyl)biphenyl (abbreviation: TPD), [Fluoren-2-yl]-N-phenylamino]biphenyl (abbreviation: DFLDPBi), 4 ,4',4''-Tris(N,N-diphenylamino)triphenylamine (abbreviation: TD ATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamine m-MTDATA, 4,4',4''-tri(N-carboxylate) Rubazolyl)triphenylamine (abbreviation: TCTA), 1,1-bis[4-(diphenyl 9,9-bis[4-(diphenylamino)phenyl]cyclohexane (abbreviation: TPAC), N-[4-(9-carbazolyl) Phenyl]-N-phenyl-9,9-dimethylfluoren-2-amine (abbreviation: YGAF ), 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3-bis(N -carbazolyl)benzene (abbreviation: mCP), 1,3,5-tris(N-carbazolyl) Low molecular weight compounds such as benzene (abbreviation: TCzB) and poly(4-vinyltriphenylamine) Poly(N-vinyl carbazole) (abbreviation: PVK) As an organic semiconductor material with electron transport properties, the following polymer compounds can be used: -[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]carba CO11, 1,3-bis[5-(p-tert-butylphenyl)-1 ,3,4-Oxadiazol-2-yl]benzene (abbreviation: OXD-7), 2-(4-biphenyl Phenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 2,2',2''-(1,3,5-benzenetriyl)tris(1- Phenyl-1H-benzimidazole) (abbreviation: TPBI), 3-(4-tert-butyl phenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-triazole( Abbreviation: TAZ01), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl p-EtTAZ , 9,9',9''-[1,3,5-triazine-2,4,6-triyl]tricarbazo 2,2',2''-(1,3,5-benzenetriyl) tetrol (abbreviation: TCzTRZ) TriMeQn, 9, 9'-(quinoxaline-2,3-diyldi-4,1-phenylene)di(9H-carbazol (abbreviation: CzQn), 3,3',6,6'-tetraphenyl-9,9'-(quinoxa Phosphorus-2,3-diyldi-4,1-phenylene)di(9H-carbazole) (abbreviation: DC zPQ), Bathophenanthroline (abbreviation: BPhen), Bathocuproine (abbreviation: BC P), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum (III) (abbreviation: BAlq), tris[2-(2-hydroxyphenyl)-5-phenyl [1,3,4-oxadiazolato]aluminum(III) (abbreviation: Al(OXD)3 ), tris(2-hydroxyphenyl-1-phenyl-1H-benzimidazolato)al Al(BIZ)3, bis[2-(2-hydroxyphenyl )benzothiazolato]zinc(II) (abbreviation: Zn(BTZ)2), bis[2-(2-hydro (phenyl)benzoxazolato]zinc(II) (abbreviation: Zn(PBO)2) Low molecular weight compounds, poly(2,5-pyridine-diyl) (abbreviation: PPy), Metal complex polymer compounds disclosed (references: XTTao, et al., Appl. De Physics Letters, Vol. 70(12), 1503-1505 (1997)) Polymer compounds such as the above can be used.

[0160] In order to improve the properties of the deposited film, a binder may also be included. As the binder, it is preferable to use an electrically inactive polymer compound. Polymethyl methacrylate (PMMA) and polyimide can be used. Cut.

[0161] The composition shown in this embodiment mode is suitable for manufacturing a light-emitting element because an organometallic complex is dissolved in the composition. In particular, the organic compounds can be used in a concentration sufficient to form a film containing an organometallic complex. Since the metal complex is dissolved, the composition can be suitably used for manufacturing a light-emitting element.

[0162] In addition, the composition described in this embodiment is a compound having a pyrazine skeleton that is capable of emitting light with high efficiency. The composition contains an organic metal complex and is suitable for producing a light-emitting device with excellent characteristics.

[0163] In addition, when a composition using alcohol as a solvent is used in manufacturing a light-emitting element, It is possible to stack the EL layers of the light-emitting element. A layer is formed on the layer containing the organic compound by using a composition using alcohol as a solvent. Therefore, a light emitting element with excellent characteristics can be manufactured.

[0164] (Embodiment 2) One embodiment of a light-emitting element using the organometallic complex or composition of the present invention and a method for manufacturing the light-emitting element The method will be explained below with reference to FIG.

[0165] In this specification, the term "composite" does not simply mean mixing two materials, but also means combining multiple materials. This means that by mixing two materials, it becomes possible for charges to be exchanged between the materials. .

[0166] The light-emitting element of the present invention has a plurality of layers between a pair of electrodes. It is made by stacking layers of materials with high carrier injection properties and materials with high carrier transport properties. These layers are stacked to form a light-emitting region away from the electrodes. In other words, the layers are stacked so that carrier recombination occurs at a location away from the electrodes. That is why.

[0167] In FIG. 1, a substrate 100 is used as a support for a light-emitting device. For example, glass or plastic can be used. Anything other than these may be used as long as it functions as a body.

[0168] In this embodiment, the light-emitting element has a first electrode 101, a second electrode 102, and The device is composed of a first electrode 101, a second electrode 102, and an EL layer 103 disposed between the first electrode 101 and the second electrode 102. In this embodiment, the first electrode 101 functions as an anode, and the second electrode 1 In the following description, the first electrode 101 functions as a cathode. The first electrode 101 and the second electrode 102 are arranged so that the potential of the first electrode 101 is higher than that of the second electrode 102. The following description will be given on the assumption that light is emitted when a voltage is applied to the electrode 102.

[0169] The first electrode 101 is made of a metal or alloy having a large work function (specifically, 4.0 eV or more). It is preferable to use gold, a conductive compound, or a mixture thereof. For example, indium tin oxide (ITO), silicon Or indium oxide-tin oxide, indium oxide-zinc oxide (I ZO: Indium Zinc Oxide, containing tungsten oxide and zinc oxide These conductive metal oxide films are usually The film is formed by sputtering, but it may also be formed by applying a sol-gel method or the like. For example, Indium oxide-zinc oxide (IZO) is a material that contains 1 to 20 wt% zinc oxide in indium oxide. It can be formed by sputtering using a target containing lead. Indium oxide containing tungsten oxide and zinc oxide (IWZO) is a type of indium oxide. The tungsten oxide content is 0.5-5wt% and the zinc oxide content is 0.1-1wt%. It can be formed by sputtering using a target. Gold (Pt), Nickel (Ni), Tungsten (W), Chromium (Cr), Molybdenum (M o), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), or metallic materials Examples of the nitrides include nitrides of the materials (for example, titanium nitride).

[0170] In addition, when a layer containing a composite material described later is used as a layer in contact with the first electrode 101, As the first electrode 101, various metals, alloys, and electrically conductive materials can be used regardless of the magnitude of the work function. For example, aluminum (A l), silver (Ag), and alloys containing aluminum (AlSi), etc. can be used. , a material with a small work function, an element belonging to group 1 or 2 of the periodic table, i.e. Alkali metals such as lithium (Li) and cesium (Cs), and magnesium (Mg) , calcium (Ca), strontium (Sr), and other alkaline earth metals, Alloys containing (MgAg, AlLi), europium (Eu), ytterbium (Yb), etc. Rare earth metals and alloys containing these can also be used. Alkali metals, alkaline earth Films of metals and alloys containing these can be formed by vacuum deposition. Alloys containing alkaline metals or alkaline earth metals can also be formed by sputtering. It is also possible to form a film using silver paste or the like by a droplet discharge method or the like.

[0171] The EL layer 103 is not particularly limited in terms of the layer stack structure, and may be made of a material having a high electron transporting property or are materials with high hole transport properties, materials with high electron injection properties, materials with high hole injection properties, and bipolar A layer including a substance (a substance having high electron and hole transport properties) and a light-emitting layer as described in this embodiment. For example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, The material for each layer can be appropriately combined. The specific details are shown below.

[0172] The hole-injection layer 111 is a layer containing a substance with high hole-injection properties. Examples include molybdenum oxide, vanadium oxide, ruthenium oxide, and tungsten oxide. , manganese oxide, etc. can be used. In addition, phthalocyanine (abbreviation: HPc) Phthalocyanine compounds such as copper phthalocyanine (abbreviation: CuPc), or poly(3 ,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PS The hole injection layer can also be formed from a polymer such as S).

[0173] In addition, a compound material in which a substance having a high hole transporting property and an acceptor substance are contained in the hole injecting layer can be used. A material having a high hole transporting property may be used. By using a material that has been subjected to the above-mentioned process, it is possible to select a material for forming the electrode regardless of the work function of the electrode. That is, the first electrode 101 can be made of not only a material having a large work function but also a material having a low work function. Materials with small acceptor potential can be used. tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), Chloranil and the like can be used. Transition metal oxides can also be used. Examples of the oxides include those of metals belonging to groups 4 to 8 of the periodic table. In particular, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, and oxide Tungsten oxide, manganese oxide, and rhenium oxide are preferred because of their high electron accepting properties. In particular, molybdenum oxide is preferred because it is stable in the air, has low hygroscopicity, and is easy to handle. .

[0174] As a substance having a high hole transporting property used in the composite material, an aromatic amine compound, carbazole, Derivatives, aromatic hydrocarbons, polymer compounds (oligomers, dendrimers, polymers, etc.) Various compounds can be used. So, 10 -6 cm 2 It is preferable that the material has a hole mobility of 1 / Vs or more. However, other materials may be used as long as they have a higher hole transporting property than electron transporting property. Specific examples of organic compounds that can be used in the composite material are listed below.

[0175] For example, an aromatic amine compound that can be used in a composite material is N,N'-bis(N-phenylenediamine). (4-Methylphenyl)(p-tolyl)-N,N'-diphenyl-p-phenylenediamine DTDPPA, 4,4'-bis[N-(4-diphenylaminophenyl)- N-phenylamino]biphenyl (abbreviation: DPAB), 4,4'-bis(N-{4-[N '-(3-methylphenyl)-N'-phenylamino]phenyl}-N-phenylamino )biphenyl (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylamino phenyl)-N-phenylamino]benzene (abbreviation: DPA3B) and the like. do.

[0176] Specific examples of carbazole derivatives that can be used in composite materials include 3-[N- (9-Phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazol 3,6-bis[N-(9-phenylcarbazole-3 -yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2) , 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino] -9-phenylcarbazole (abbreviation: PCzPCN1), etc.

[0177] In addition, carbazole derivatives that can be used in composite materials include 4,4'-di(N -carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl) 9-[4-(10-phenyl-9-azolyl)phenyl]benzene (abbreviation: TCPB), 1,4-bis[4-( N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene, etc. This can be done.

[0178] In addition, examples of aromatic hydrocarbons that can be used in the composite material include 2-tert -Butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2- tert-Butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3, 5-Diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9 ,10-Bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,1 0-Di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene 2-tert-butylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAn th), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA) , 9,10-bis[2-(1-naphthyl)phenyl]-2-tert-butyl-anthracene 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7 -Tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl- Methyl-9,10-di(2-naphthyl)anthracene, 9,9'-bianthryl, 10, 10'-diphenyl-9,9'-bianthryl, 10,10'-bis(2-phenylphenyl) 10,10'-bis[(2,3,4,5,6-pentanyl) Phenyl)phenyl]-9,9'-bianthryl, anthracene, tetracene, rubrene , perylene, and 2,5,8,11-tetra(tert-butyl)perylene. In addition, pentacene, coronene, etc. can also be used. - 6 cm 2 / Vs or more, and uses aromatic hydrocarbons with carbon numbers of 14 to 42. It is more preferable to do so.

[0179] The aromatic hydrocarbon that can be used in the composite material may have a vinyl skeleton. Examples of aromatic hydrocarbons having a vinyl group include 4,4'-bis(2,2- Diphenylvinyl)biphenyl (abbreviation: DPVBi), 9,10-bis[4-(2,2- diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA), and the like.

[0180] The hole injection layer 111 may be made of a polymer compound (oligomer, dendrimer, polymer, etc.). For example, poly(N-vinylcarbazole) (abbreviation: PVK ), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{ N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino} Poly[N,N'-bis(4-butylphenyl)methacrylamide] (abbreviation: PTPDMA) phenyl)-N,N'-bis(phenyl)benzidine (abbreviation: Poly-TPD), etc. In addition, the following polymer compounds can be used: poly(3,4-ethylenedioxythiophene) / poly Poly(styrene sulfonate) (PEDOT / PSS), Polyaniline / Poly(styrene sulfonate) A polymer compound to which an acid such as polyaniline sulfonate (PAni / PSS) has been added can be used.

[0181] In addition, the above-mentioned polymer compounds such as PVK, PVTPA, PTPDMA, and Poly-TPD A composite material is formed using the above-mentioned acceptor substance, and the composite material is used as the hole injection layer 111. It may be used.

[0182] The hole-transporting layer 112 is a layer containing a substance having a high hole-transporting property. Examples of such compounds include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl. N,N'-bis(3-methylphenyl)-N, N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4',4''-Tris(N,N-diphenylamino)triphenylamine (abbreviation: T DATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylalanine amino]triphenylamine (abbreviation: MTDATA), 4,4'-bis[N-(spiro-9 ,9'-Bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB ) and other aromatic amine compounds can be used. The substances mentioned here are mainly 10 - 6 cm 2 / Vs or higher. However, it has a higher hole transporting property than electron transporting property. Other substances may be used as long as they have a high hole transporting property. The layer containing the above-mentioned material may be not only a single layer, but also a laminate of two or more layers of the above-mentioned material. stomach.

[0183] The hole transport layer 112 may be made of PVK, PVTPA, PTPDMA, or Poly-TP Polymer compounds such as D can also be used.

[0184] The light-emitting layer 113 is a layer containing a highly light-emitting substance. The organometallic complex of the present invention shown in Form 1 can be used. Since it exhibits high luminous efficiency, it can be suitably used as a luminescent material for a light-emitting element.

[0185] In particular, in the light-emitting layer 113, a structure in which the organometallic complex of the present invention is dispersed in a host material is preferable. As the host material, a hole-transporting organic semiconductor as described in the first embodiment is preferable. Body materials (e.g. NPB, PPB, TPD, DFLDPBi, TDATA, m-MTDAT A, TCTA, TPAC, TPAF, YGAF, CBP, mCP, TCzB, PVTPA , PVK) and electron transporting organic semiconductor materials (CO11, OXD-7, PBD, TPBI , TAZ01, p-EtTAZ, TCzTRZ, TriMeQn, CzQn, DCzPQ , BPhen, BCP, BAlq, Al(OXD)3, Al(BIZ)3, Zn(BTZ )2, Zn(PBO)2, PPy), metal complex polymer compounds disclosed in the following references: (References: XTTao and 5 others, Applied Physics Letters, Vol. .70(12), 1503-1505(1997)) can also be used. Preferably, both the hole-transporting organic semiconductor material and the electron-transporting material are used as the organic semiconductor material. It is preferable to use it as a resist material in order to improve the element life.

[0186] The light-emitting layer 113 can be formed by using various methods, regardless of whether they are a dry method or a wet method. For example, the film can be formed by a vapor deposition method, which is a dry method. The light-emitting layer 113 can be formed by a wet process using a composition containing the organometallic complex of the present invention. Specifically, the composition shown in Embodiment 1 can be applied by a droplet discharge method or a spin coating method. The solvent may be removed by applying the solvent to the coating solution using a solvent such as ... Examples of the method include a method of performing a heat treatment under reduced pressure, a treatment under reduced pressure, or the like.

[0187] In this case, the solvent contained in the composition is preferably alcohol, for the following reasons. Many of the low molecular weight compounds used in light emitting devices are difficult to dissolve in alcohol. Therefore, when the solvent contained in the composition is alcohol, the light emitting layer Even if the layer formed earlier is a layer containing a low molecular weight compound formed by a deposition method or the like, It is possible to laminate the light-emitting layer by wet coating the composition.

[0188] The electron transport layer 114 is a layer containing a substance having a high electron transporting property. Aluminum (Alq), tris(4-methyl-8-quinolinolato) Aluminum (abbreviation: Almq3), bis(10-hydroxybenzo[h]quinolinato) Beryllium (abbreviation: BeBq2), bis(2-methyl-8-quinolinolato)(4-phenyl Alphenolato)aluminum (abbreviation: BAlq), etc. Metal complexes having a bis[2-(2-hydroxyphenyl)-2-propane skeleton can also be used. 2-(2-phenyl)benzoxazolato]zinc (abbreviation: Zn(BOX)2), -Hydroxyphenyl)benzothiazolato]zinc (abbreviation: Zn(BTZ)2) Metal complexes having thazole or thiazole ligands can also be used. In addition to metal complexes, 2-(4-biphenylyl)-5-(4-tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD) and 1,3-bis[5-(p-tert-butyl ether] t-Butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: O XD-7), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butyl) phenyl)-1,2,4-triazole (abbreviation: TAZ), bathophenanthroline (abbreviation: BPhen), bathocuproine (abbreviation: BCP), etc. can also be used. The solid material is mainly 10 -6 cm 2 / Vs or higher. Any other material that has a higher electron transporting capacity than holes may be used as the electron transport layer. The electron transport layer may be not only a single layer, but also two or more layers made of the above-mentioned material. It may also be a laminate.

[0189] Furthermore, a polymer compound can be used as the electron transport layer 114. For example, poly[ (9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl) Poly[(9,9-dioctylfluorene-2,7-diyl)] (abbreviation: PF-Py) )-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviation: PF-BPy), etc. can be used.

[0190] In addition, an electron injection layer 115 may be provided. The electron injection layer 115 may be formed of lithium fluoride. AlF, Cesium Fluoride (CsF), Calcium Fluoride (CaF2), etc. Potassium metal compounds or alkaline earth metal compounds can be used. A layer containing a combination of a material having this property and an alkali metal or alkaline earth metal may also be used. For example, Alq containing magnesium (Mg) can be used. The electron injection layer is formed by combining a substance having electron transport properties with an alkali metal or an alkaline earth metal. The use of the combined layer allows for more efficient electron injection from the second electrode 102. preferable.

[0191] The material for forming the second electrode 102 is a material having a small work function (specifically, 3.8 eV Metals, alloys, electrically conductive compounds, and mixtures thereof can be used. Examples of such cathode materials include elements belonging to Groups 1 and 2 of the Periodic Table. , i.e., alkali metals such as lithium (Li) and cesium (Cs), and magnesium Alkaline earth metals such as Mg, Ca, and Sr, Alloys containing these elements (MgAg, AlLi), europium (Eu), ytterbium (Y b) Rare earth metals and alloys containing these. Alkali metals, alkaline earth metals, etc. Films of metals and alloys containing these can be formed by vacuum deposition. Alloys containing alkaline metals or alkaline earth metals can also be formed by sputtering. It is also possible to form a film using silver paste or the like by a droplet discharge method or the like.

[0192] In addition, an electron injection layer 115 is provided between the second electrode 102 and the electron transport layer 114. Therefore, regardless of the magnitude of the work function, materials containing Al, Ag, ITO, silicon or silicon oxide can be used. Various conductive materials can be used as the second electrode 102, such as indium oxide-tin oxide. These conductive materials can be deposited by sputtering, droplet ejection, spin coating, etc. It is possible to form a film using this method.

[0193] The light-emitting element having the above-described structure described in this embodiment has a first electrode 101 and a second electrode 102. By applying a voltage between the electrode 102, a current flows. In the light-emitting layer 113, which is a layer containing the compound, holes and electrons recombine to emit light. That is, a light emitting region is formed in the light emitting layer 113 .

[0194] The light is emitted through either the first electrode 101 or the second electrode 102, or both. Therefore, either the first electrode 101 or the second electrode 102 Alternatively, both electrodes are made of a material having light-transmitting properties. Only the first electrode 101 is an electrode having light-transmitting properties. In this case, light passes through the first electrode 101 and is extracted from the substrate side. When 102 is the only electrode having light-transmitting properties, the light passes through the second electrode 102 and exits to the opposite side of the substrate. Both the first electrode 101 and the second electrode 102 are light-transmitting. In the case of the electrode, light passes through the first electrode 101 and the second electrode 102 to the substrate side and It is taken out from both the substrate side and the opposite side.

[0195] In FIG. 1, the first electrode 101 functioning as an anode is provided on the substrate 100 side. However, the second electrode 102 functioning as a cathode may be provided on the substrate 100 side. In FIG. 2, a second electrode 102 functioning as a cathode, an EL layer 103, an anode The EL layer 103 is configured by stacking a first electrode 101 that functions as an EL layer. , are stacked in the reverse order to the configuration shown in FIG.

[0196] The EL layer can be formed by various methods, including dry and wet methods. Also, each electrode or each layer may be formed by using a different film formation method. Examples of the wet method include a vacuum deposition method and a sputtering method. Examples of the method include a discharge method and a spin coating method.

[0197] For example, the EL layer may be formed by a wet process using a polymer compound among the above-mentioned materials. Alternatively, it can be formed by a wet process using a low molecular weight organic compound. The EL layer may be formed by using an organic compound and a dry method such as a vacuum deposition method.

[0198] The light-emitting layer 113 can be formed by a variety of methods, including dry and wet methods. However, it is preferable to form the film by a wet method using the composition shown in the first embodiment. The composition shown in the embodiment mode 1 is applied by a droplet discharge method, a spin coating method, or the like. The solvent can be removed by a method such as a heat treatment or a reduced pressure treatment. or a method of performing heat treatment under reduced pressure. This makes it possible to improve the efficiency of material utilization and reduce the manufacturing cost of the light-emitting element.

[0199] The electrodes may also be formed by a wet method using a sol-gel method, or may be formed of a metal material. It may be formed by a wet method using a paste. It may also be formed by a sputtering method, a vacuum deposition method, or the like. It may be formed by using a dry method.

[0200] Note that when the light-emitting element shown in this embodiment mode is applied to a display device and the light-emitting layer is divided into different colors, In the case where the light-emitting layer is formed by a droplet discharge method, it is preferable that the light-emitting layer is formed by a wet method. This makes it easy to apply different coatings to the light-emitting layers even on a large substrate, improving productivity.

[0201] A specific method for forming the light emitting element will be described below.

[0202] For example, in the configuration shown in FIG. 1, the first electrode 101 is formed by a dry method such as sputtering. The hole injection layer 111 is formed by a wet method such as a droplet discharge method or a spin coating method, and the hole transport layer 112 is formed by a wet method such as a droplet discharge method or a spin coating method. The light-emitting layer 113 is formed by a dry method, such as vacuum deposition, the light-emitting layer 113 is formed by a wet method, such as droplet discharge, and the electron transport layer 114 is formed by a wet method, such as a vacuum deposition method. The electron injection layer 115 is formed by a vacuum deposition method, which is a dry method, and the second electrode 10 is formed by a vacuum deposition method, which is a dry method. The first electrode 2 may be formed by a wet method such as a droplet discharge method or a spin coating method. The electrode 101 is formed by a wet droplet ejection method, the hole injection layer 111 is formed by a dry vacuum deposition method, and the hole The transport layer 112 is formed by a wet method such as a droplet discharge method or a spin coating method, and the light emitting layer 113 is formed by a wet method such as a A droplet discharge method, an electron transport layer 114 is formed by a wet method such as a droplet discharge method or a spin coating method, and an electron injection layer The second electrode 102 is formed by a wet method such as a droplet discharge method or a spin coating method. The film may be formed by a droplet discharge method or a spin coating method. and the dry method may be appropriately combined.

[0203] For example, in the case of the configuration shown in FIG. 1, the first electrode 101 is formed by a dry method, that is, a sputtering method. The hole injection layer 111 and the hole transport layer 112 are formed by a wet method such as a droplet discharge method or a spin coating method. The light-emitting layer 113 is formed by a liquid droplet ejection method, which is a wet method. The electron transport layer 114 and the electron injection layer 115 are formed by a liquid droplet ejection method, which is a wet method. The second electrode 102 is formed by a vacuum deposition method, which is a dry method. That is, a hole injection layer 102 is formed on a substrate on which a first electrode 101 is formed in a desired shape. The layers 111 to the light-emitting layer 113 are formed by a wet process, and the layers 114 to the second electrode 102 are formed by a wet process. In this method, the layers from the hole injection layer 111 to the light emitting layer 11 can be formed by a dry process. The layers 111 to 113 can be formed at atmospheric pressure, and the light-emitting layer 113 can be easily painted separately. The electron transport layer 114 to the second electrode 102 can be formed in a vacuum. This simplifies the process and improves productivity.

[0204] An example is shown below. On the first electrode 101, a PEDOT / PS Since PEDOT / PSS is water-soluble, it can be applied as an aqueous solution by spin coating or The hole transport layer 112 is not provided, and the hole injection layer 113 is not provided. The light-emitting layer 113 is provided on the hole injection layer 111. 11 Solvents in which (PEDOT / PSS) does not dissolve (toluene, xylene, dodecylbenzene , or a mixture of dodecylbenzene and tetralin, ethers, alcohols, etc. The composition shown in Embodiment 1 can be used to form the insulating film by a droplet discharge method. Next, the electron transport layer 114 is formed on the light emitting layer 113 by a wet process. When the hole injection layer 111 and the light emitting layer 113 are formed, the hole injection layer 111 and the light emitting layer 113 that are already formed are dissolved. In this case, the solvent selection is limited, so dry Therefore, it is easier to form the electron transport layer 114 and the second electrode 102 by using the above-mentioned method. By forming the film in a vacuum using the dry vacuum deposition method, the process is simplified. It is possible.

[0205] In the case of the configuration shown in FIG. 2, the second electrode 102 is dry-coated in the reverse order to the above method. The electron injection layer 115 to the electron transport layer 114 are then dried by sputtering or vacuum deposition, which is a method for forming the electron transport layer 114. the light-emitting layer 113 by a liquid droplet ejection method, the hole transport layer 112 by a liquid droplet ejection method, and the The hole injection layer 111 is formed by a wet method such as a droplet discharge method or a spin coating method, and the first electrode 101 is formed by a wet method such as a droplet discharge method or a spin coating method. The film can be formed by a droplet discharge method or a spin coating method. The layers from the electrode 102 to the electron transport layer 114 are formed in a vacuum by a dry process, and the light-emitting layer 11 3 to the first electrode 101 can be formed at atmospheric pressure. This simplifies the process. The composition shown in the first embodiment can be formed by a deposition method or the like. Since it is possible to coat the layer formed by the above method, such a production method is also possible.

[0206] In this embodiment, a light emitting element is formed on a substrate made of glass, plastic, or the like. By fabricating multiple light-emitting devices on a single substrate, a passive matrix In addition, a glass or plastic substrate can be used to fabricate a glass-type light-emitting device. For example, a thin film transistor (TFT) is formed on the plate, and a voltage source electrically connected to the TFT is provided. A light-emitting element may be fabricated on the electrode. This allows the driving of the light-emitting element to be controlled by the TFT. In addition, the structure of the TFT is not particularly limited. The TFT substrate may be a staggered type TFT or an inverted staggered type TFT. The driving circuit formed in the display may be made of N-type and P-type TFTs. Alternatively, it may be composed of only one of N-type TFTs or P-type TFTs. There is no particular restriction on the crystallinity of the semiconductor film used in the TFT. A conductor film or a crystalline semiconductor film may be used.

[0207] The light-emitting element of the present invention has high luminous efficiency because it contains an organometallic complex capable of emitting light with high efficiency. .

[0208] In addition, when a light-emitting element is formed using the composition shown in Embodiment 1, Therefore, the light-emitting layers can be easily coated separately, and the productivity can be improved. The method for manufacturing light-emitting elements is suitable for mass production. In addition, the efficiency of material utilization is high, so manufacturing costs are low. The amount of damage can be reduced.

[0209] (Embodiment 3) The present embodiment relates to a light-emitting device having a structure in which a plurality of light-emitting units according to the present invention are stacked (hereinafter, referred to as stacked). The embodiment of the light-emitting device (hereinafter referred to as a layer type device) will be described with reference to FIG. The light-emitting device is a stacked type light-emitting device having a plurality of light-emitting units between a first electrode and a second electrode. The EL layer may have a structure similar to that of the EL layer shown in the embodiment mode 2. The light-emitting element shown in the second embodiment has one light-emitting unit. In the embodiments, a light emitting device having a plurality of light emitting units will be described.

[0210] In FIG. 3, a first light-emitting unit 501 is disposed between a first electrode 501 and a second electrode 502. 11, a charge generating layer 513, and a second light emitting unit 512 are laminated. The first and second electrodes 502 can be the same as those in the second embodiment. The first light-emitting unit 511 and the second light-emitting unit 512 may have the same configuration or different configurations. The configuration thereof may be the same as that of the second embodiment.

[0211] The charge generating layer 513 contains a composite material of an organic compound and a metal oxide. The composite material of an organic compound and a metal oxide is the composite material shown in the second embodiment. These include metal oxides such as vanadium oxide, molybdenum oxide, and tungsten oxide. Examples of compounds include aromatic amine compounds, carbazole derivatives, aromatic hydrocarbons, and polymer compounds (O Various compounds such as oligomers, dendrimers, polymers, etc. can be used. As an organic compound, the hole mobility is 10 -6 cm 2 / Vs or more. However, other materials that have a higher hole transporting property than electron transporting property may be used. A composite material of an organic compound and a metal oxide has a carrier injection property, a carrier transport property, and Since it has excellent characteristics, it can be driven at a low voltage and a low current.

[0212] The charge generating layer 513 is made of a composite material of an organic compound and a metal oxide, and other materials. For example, a layer including a composite material of an organic compound and a metal oxide and an electron donor may be formed. A compound selected from among the active substances and a layer containing a compound having high electron transport properties are combined. Alternatively, a layer containing a composite material of an organic compound and a metal oxide and a transparent conductive film may be formed. may be formed in combination.

[0213] The charge generating layer 513 sandwiched between the first light emitting unit 511 and the second light emitting unit 512 is When a voltage is applied between the first electrode 501 and the second electrode 502, the light-emitting unit on one side Any device that injects electrons into the light-emitting unit on one side and holes into the light-emitting unit on the other side can be used. For example, in FIG. 3, the potential of the first electrode is higher than the potential of the second electrode. When a voltage is applied so that the charge generation layer 513 emits a high light, the charge generation layer 513 emits a high light. It is sufficient that the second light-emitting unit 512 injects electrons into the first light-emitting unit 512 and injects holes into the second light-emitting unit 512.

[0214] In this embodiment, the light emitting element having two light emitting units has been described. However, the light emitting element having three or more light emitting units may be used. The same can be applied to a light-emitting device in which the above light-emitting units are stacked. As in the light-emitting device according to the embodiment, a plurality of light-emitting units are disposed between a pair of electrodes by a charge generating layer. By separating the layers, it is possible to emit light in a high-brightness region while keeping the current density low. Therefore, a long-life element can be realized. In addition, when applied to lighting, the resistance of the electrode material This reduces the voltage drop caused by the low voltage drive, enabling uniform light emission over a large area. It is possible to realize a light emitting device that can be operated automatically and has low power consumption.

[0215] In addition, by making the emission color of each light-emitting unit different, For example, a light-emitting element having two light-emitting units can be used. In the above, the luminous color of the first light-emitting unit and the luminous color of the second light-emitting unit are in a complementary color relationship. By doing so, it is possible to obtain a light emitting element that emits white light as a whole. In addition, complementary colors are colors that become achromatic when mixed together. When light from a substance that emits light of a certain color is mixed with the light, white light can be obtained. The same applies to the case of a light-emitting element having three light-emitting units. For example, the first light-emitting unit The emission color of the first light-emitting unit is red, the emission color of the second light-emitting unit is green, and the emission color of the third light-emitting unit is red. When the light emitted from the dot is blue, the light emitting element as a whole can emit white light.

[0216] Note that this embodiment mode can be appropriately combined with other embodiment modes.

[0217] (Embodiment 4) In this embodiment mode, a light emitting device having a light emitting element of the present invention will be described.

[0218] In this embodiment, a light-emitting device having a light-emitting element of the present invention in a pixel portion will be described with reference to FIG. FIG. 4A is a top view showing a light-emitting device, and FIG. 4B is an A-side view of FIG. This light emitting device is a cross-sectional view taken along the lines A' and B-B'. The following are shown: a driving circuit section (source side driving circuit) 601, a pixel section 602, The driving circuit section (gate side driving circuit) 603 is included. In addition, 604 is a sealing substrate, 605 is a sealant, and the inside surrounded by the sealant 605 forms a space 607 .

[0219] The lead wiring 608 is connected to the source side driver circuit 601 and the gate side driver circuit 603. The wiring is for transmitting the input signal, and the FPC (flexible printed circuit board) is the external input terminal. Video signal, clock signal, start signal, reset signal from Lint Circuit 609 Although only the FPC is shown here, the FPC has a printed circuit board. A printed wiring board (PWB) may be attached. This includes not only the device itself, but also the state in which an FPC or PWB is attached to it. do.

[0220] Next, the cross-sectional structure will be described with reference to FIG. A source side driver circuit 601, which is a driver circuit section, and a pixel section are formed in this example. 6, one pixel in the pixel section 602 is shown.

[0221] The source side driver circuit 601 includes an N-channel TFT 623 and a P-channel TFT 62 4 is combined to form a CMOS circuit. The driving circuit is also a variety of CMOS circuits. Alternatively, the pixel may be formed of a PMOS circuit or an NMOS circuit. The driver integrated type is shown in which the driver circuit is formed on the substrate on which the part is formed, but this is not necessarily required. Alternatively, the driver circuit may be formed outside the substrate on which the pixel portion is formed, instead of on the substrate on which the pixel portion is formed.

[0222] The pixel section 602 includes a switching TFT 611, a current control TFT 612, and The pixel is formed of a plurality of pixels including a first electrode 613 electrically connected to the drain. An insulator 614 is formed to cover the end of the first electrode 613. It is formed by using a photosensitive acrylic resin film of a mold.

[0223] In order to improve the covering property, the upper end or the lower end of the insulator 614 is provided with a curvature. For example, the material of the insulator 614 is a positive photosensitive adhesive. When using krill, the insulator 614 has a radius of curvature (0.2 μm to 3 μm) only at the top end. It is preferable that the insulating material 614 has a curved surface that changes its edge when irradiated with light. Negative type that becomes insoluble in etchant or becomes soluble in etchant when exposed to light Any positive type may be used.

[0224] An EL layer 616 and a second electrode 617 are formed on the first electrode 613. Here, the material used for the first electrode 613 may be various metals, alloys, and Conductive compounds and mixtures thereof can be used. The first electrode is used as an anode. In particular, metals, alloys, and It is preferable to use electrically conductive compounds and mixtures thereof. For example, silicon Indium oxide-tin oxide film, indium oxide-zinc oxide film, titanium nitride film, In addition to single-layer films such as ROM, tungsten, Zn, and Pt, titanium nitride and aluminum are also available. a titanium nitride film, an aluminum-based film, and a titanium nitride film A laminated film such as a three-layer structure with a film can be used. The resistance of the electrode is low, good ohmic contact can be achieved, and the electrode can function as an anode. can.

[0225] The EL layer 616 contains the organometallic complex described in the first embodiment. 6 can be formed by various methods such as deposition using a deposition mask, droplet ejection, and spin coating. The EL layer 616 is formed from a material selected from a low molecular weight compound and a high molecular weight compound. Any compound (including oligomers and dendrimers) may be used. The material to be used may be not only an organic compound but also an inorganic compound.

[0226] The second electrode 617 may be made of various metals, alloys, or electrically conductive materials. When the second electrode is used as a cathode, Among them, metals, alloys, and electrical conductors with small work functions (work functions of 3.8 eV or less) For example, the compounds of the periodic table of the elements Elements belonging to groups 1 and 2, i.e., lithium (Li) and cesium (Cs), Potash metal, as well as magnesium (Mg), calcium (Ca), and strontium (Sr) and alloys containing these (MgAg, AlLi). In addition, when the light generated in the EL layer 616 is transmitted through the second electrode 617, As 617, a thin metal film and a transparent conductive film (indium oxide-tin oxide (I TO), indium oxide containing silicon or silicon oxide - tin oxide, indium oxide - Zinc oxide (IZO), tungsten oxide and indium oxide containing zinc oxide (IWZ It is also possible to use a laminate with a polyimide (e.g., O).

[0227] Furthermore, the sealing substrate 604 is bonded to the element substrate 610 with a sealant 605. A light-emitting element is disposed in a space 607 surrounded by an element substrate 610, a sealing substrate 604, and a sealant 605. The space 607 is filled with a filler. In addition to the case where an inert gas (nitrogen, argon, etc.) is filled, the sealing material 605 is filled. In some cases.

[0228] It is preferable to use an epoxy resin for the sealing material 605. It is preferable that the sealing substrate 604 is made of a material that is as impermeable to moisture and oxygen as possible. In addition to glass and quartz substrates, FRP (Fiberglass-Reinforced Plastics) is also used as a material for unforced Plastics), PVF (Polyvinyl fluoride), Polyester Alternatively, a plastic substrate made of acrylic or the like can be used.

[0229] In the above manner, a light-emitting device having a light-emitting element of the present invention can be obtained.

[0230] The light emitting device of the present invention has a light emitting element with high light emitting efficiency, and therefore consumes less power. is.

[0231] The light emitting device of the present invention can be formed using the composition shown in Embodiment 1. This makes it suitable for mass production. In addition, the efficiency of material utilization is high, which reduces manufacturing costs. This makes it possible to obtain a low-cost light-emitting device.

[0232] As described above, in this embodiment, an amplifier that controls driving of a light-emitting element by a transistor is provided. Although the active matrix type light emitting device has been described above, there are also passive matrix type light emitting devices. FIG. 5 shows a passive matrix type light emitting device manufactured by applying the present invention. FIG. 5(A) is a perspective view showing a light emitting device, and FIG. 5(B) is a perspective view showing FIG. 5(A). 5 is a cross-sectional view taken along the line XY. In FIG. An EL layer 955 is provided between the electrode 952 and the insulating layer 953. A partition layer 954 is provided on the insulating layer 953. As the side walls approach the substrate surface, the distance between the side walls becomes narrower. In other words, the cross section of the partition layer 954 in the short side direction is trapezoidal, and the base ( The side that faces the insulating layer 953 and is in contact with the insulating layer 953 is the upper side (insulating The side of the insulating layer 953 is oriented in the same direction as the surface direction of the insulating layer 953 and is shorter than the side that is not in contact with the insulating layer 953. By providing the partition layer 954 as shown in FIG. Even in a sub-matrix light-emitting device, by including a light-emitting element with high light-emitting efficiency, It can be operated with low power consumption.

[0233] (Embodiment 5) In this embodiment, the layer 7 containing the organometallic complex of the present invention is formed by a droplet discharge method as a wet method. One embodiment of forming 16 will be described with reference to Figs. 10(A) to 10(D). ) shows a manufacturing process of the light emitting element portion of the light emitting device shown in FIG.

[0234] In FIG. 10A, a first electrode 713 is formed on an insulating layer 719. An insulating layer 714 is formed so as to cover a part of the insulating layer 13. A droplet 731 is discharged from a droplet discharge device 730 onto the exposed portion of the electrode 713, and a layer containing a composition is formed. The droplet 731 is a composition including an organometallic complex of the present invention and a solvent. The layer 732 is deposited on the first electrode 713 (see FIG. 10B). The organic metal complex-containing layer 716 is formed by removing the organic metal complex and solidifying the organic metal complex (FIG. 10C). The solvent may be removed by drying or by adding a heating step. The step of discharging the composition may be carried out under reduced pressure.

[0235] A second electrode 717 is formed on the layer 716 containing an organometallic complex to form a light-emitting element 718. (See FIG. 10D). Note that in FIG. 10, the first electrode 713 and the second electrode 717 Although the structure having only the layer 716 containing an organometallic complex between the first electrode 713 and the A layer containing another material may be formed between the layer 716 containing the organic metal complex. As shown in , the organometallic complex of the present invention is soluble in alcohol, so that the solvent is alcohol. When a composition using coal is used, it becomes possible to laminate an EL layer of a light-emitting device. In addition, a layer containing another material is formed between the layer 716 containing the organometallic complex and the second electrode 717. This is also fine.

[0236] As shown in this embodiment mode, when the layer 716 containing an organometallic complex is formed by a droplet discharge method, selective Since the composition can be discharged onto the formation region easily, loss of material can be reduced. In addition, the process is simplified because photolithography processes for processing the shape are not required. This allows for cost reduction.

[0237] The droplet discharge means shown in this embodiment is a nozzle having a composition discharge port, or one or more A general term for anything that has a means for ejecting droplets, such as a head equipped with multiple nozzles.

[0238] One embodiment of a droplet discharge device used in the droplet discharge method is shown in FIG. Each head 1405 and head 1412 is connected to a control means 1407, which controls a computer. By controlling the laser 1410, it is possible to draw a pre-programmed pattern. The timing of drawing can be determined, for example, by setting the marker 1411 formed on the substrate 1400. Alternatively, the edge of the substrate 1400 may be used as a reference point to determine the reference point. This is detected by the imaging means 1404 and converted into a digital signal by the image processing means 1409. The computer 1410 recognizes the detected image and generates a control signal to send it to the control means 1407. The imaging means 1404 may be a charge-coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS). Of course, an image sensor using a semiconductor laser formed on the substrate 1400 can be used. The information on the pattern to be printed is stored in the storage medium 1408. A control signal is sent to the control means 1407, and each head 1405 of the droplet ejection means 1403, The heads 1412 can be individually controlled. The material to be discharged is supplied from a material supply source 1413, The material is supplied from a material supply source 1414 through piping to heads 1405 and 1412. can be.

[0239] Inside the head 1405, as shown by the dotted line 1406, there is a space for filling the liquid material and a space for discharging the material. Although not shown, the head 1412 and the head 14 The head 1405 and head 1412 have different nozzle sizes. By providing the heads in different sizes, different materials can be printed at the same time with different widths. It is possible to discharge multiple types of luminescent materials and draw on them. When drawing on a wide area, In order to improve throughput, the same material is ejected from multiple nozzles at the same time to create a pattern. When a large substrate is used, the head 1405 and the head 1412 move on the substrate in the direction of the arrow. The scanning direction can be freely changed and the area to be drawn can be freely set. Multiple drawings can be made on the board.

[0240] The step of discharging the composition may be carried out under reduced pressure. After the composition is discharged, one or both of the steps of drying and baking are performed. Both processes are heat treatment processes. For example, drying is done at 80 to 100 degrees (℃) for 3 minutes. The firing is carried out at 200 to 550 degrees (℃) for 15 to 60 minutes. The drying and baking processes are carried out under normal or reduced pressure with laser light. This is done by irradiation, flash thermal annealing, heating furnace, etc. The timing of this heat treatment is as follows: The number of times of the heat treatment is not particularly limited. In order to perform the drying and baking processes well, The temperature depends on the substrate material and the nature of the composition.

[0241] Note that this embodiment mode can be appropriately combined with other embodiment modes.

[0242] (Embodiment 6) In this embodiment, an electronic device of the present invention includes the light-emitting device shown in Embodiment 4 as a part thereof. The electronic devices of the present invention are manufactured using the organometallic complexes shown in Embodiment 1. The display portion has a light-emitting element and has reduced power consumption.

[0243] As an example of an electronic device having a light-emitting element manufactured using the organometallic complex of the present invention, a video camera cameras, digital cameras, goggle-type displays, navigation systems, audio playback equipment (car audio, audio components, etc.), computers, game devices, mobile information terminals (Mobile computers, mobile phones, portable game consoles, e-books, etc.), equipped with recording media Image playback devices that incorporate the Digital Versatile Disc (DVD) ) and a display device capable of reproducing the image from the recording medium, such as a digital camera. Specific examples of these electronic devices are shown in Figure 6.

[0244] FIG. 6A shows a television device according to the present invention, which includes a housing 9101, a support stand 9102, a display unit 9103, a speaker section 9104, a video input terminal 9105, etc. In the display portion 9103, a matrix of light-emitting elements similar to those described in the second and third embodiments is used. The light emitting element is characterized by high light emitting efficiency. The display portion 9103 that is composed of the light-emitting elements has the same characteristics. The device is designed to consume less power. Since the circuit can be significantly reduced or downsized, the housing 9101 and the support 9102 The television device according to the present invention has low power consumption and high image quality. The product is also compact and lightweight, making it possible to provide a product that is suited to the living environment. can.

[0245] FIG. 6B shows a computer according to the present invention, which includes a main body 9201, a housing 9202, a display unit 9203, keyboard 9204, external connection port 9205, pointing device 92 In this computer, the display unit 9203 includes the display unit 9202 described in the second and third embodiments. The light emitting element is configured by arranging light emitting elements similar to those described above in a matrix. The display portion 9203 that is made up of the light-emitting element has the same characteristic of being highly efficient in terms of light emission. Due to these features, this computer consumes less power. This feature allows the power supply circuit in a computer to be significantly reduced or downsized. Therefore, the main body 9201 and the housing 9202 can be made smaller and lighter. The computers used in the project are designed to consume less power, have high image quality, and are compact and lightweight, making them environmentally friendly. We can provide products that meet these requirements.

[0246] FIG. 6C shows a mobile phone according to the present invention, which includes a main body 9401, a housing 9402, a display unit 94 03, audio input unit 9404, audio output unit 9405, operation keys 9406, external connection port 9 407, an antenna 9408, etc. In this mobile phone, the display portion 9403 is The light emitting device is configured by arranging light emitting elements similar to those explained in the second and third embodiments in a matrix. The light-emitting element has a feature of having high light-emitting efficiency. The display unit 9403 also has similar features, so that this mobile phone consumes less power. These features make it possible to significantly reduce or downsize the power supply circuit in a mobile phone. Therefore, the main body 9401 and the housing 9402 can be made smaller and lighter. The mobile phone according to the invention has low power consumption, high image quality, and is small and lightweight, making it easy to carry around. We can provide suitable products.

[0247] FIG. 6D shows a camera according to the present invention, which includes a main body 9501, a display section 9502, and a housing 950 3, external connection port 9504, remote control receiver 9505, image receiver 9506, battery 9 507, a voice input unit 9508, operation keys 9509, an eyepiece unit 9510, etc. In the display portion 9502, the light-emitting element similar to that described in the second and third embodiments is used as a base. The light-emitting element is characterized by high luminous efficiency. The display portion 9502 which is made up of the light-emitting elements has the same characteristics. This feature allows the power supply circuit in the camera to be It is possible to reduce or shrink the size of the main body 9501 significantly, making it smaller and lighter. The camera according to the present invention is designed to consume less power, provide high image quality, and be compact and lightweight. This makes it possible to provide products that are suitable for portability.

[0248] As described above, the light-emitting device of the present invention has a very wide range of applications, and can be used in a variety of fields. By using the light-emitting element of the present invention, it is possible to reduce power consumption. It is possible to provide an electronic device having a low-power display unit. Since the light-emitting element is formed using the composition shown in the first embodiment, it is possible to mass-produce the light-emitting element. In addition, the efficiency of material utilization is high, reducing manufacturing costs. You can get electronic devices like this.

[0249] The light-emitting device of the present invention can also be used as a lighting device. An embodiment of the present invention used as a lighting device will be described with reference to FIG.

[0250] FIG. 7 shows an example of a liquid crystal display device using the light emitting device of the present invention as a backlight. The liquid crystal display device shown in FIG. 7 includes a housing 901, a liquid crystal layer 902, a backlight 903, and a housing 90 4, and the liquid crystal layer 902 is connected to a driver IC 905. The light emitting device of the present invention is used in the reference numeral 903, and a current is supplied to the light emitting device through a terminal 906. .

[0251] By using the light emitting device of the present invention as a backlight for a liquid crystal display device, the power consumption can be reduced. In addition, the light emitting device of the present invention is a surface-emitting lighting device. Since the area can be increased, the backlight area can be increased and the LCD display can be made larger. Furthermore, since the light emitting device of the present invention is thin and consumes low power, The display device can be made thinner and consume less power. Since it is formed using the composition shown in 1, it has excellent mass productivity. In addition, the material utilization efficiency is also improved. Since the efficiency is high, the manufacturing cost is reduced, and a low-cost light-emitting device can be obtained. Therefore, a liquid crystal display device using the light emitting device of the present invention has the same characteristics.

[0252] FIG. 8 shows an example in which a light-emitting device to which the present invention is applied is used as a desk lamp, which is a lighting device. The desk lamp shown in FIG. 8 has a housing 2001 and a light source 2002. The light emitting device of the present invention is capable of emitting light with high luminance. Therefore, it is possible to brightly illuminate the area close to the user's hands when performing detailed work. Since the light-emitting device is formed using the composition described in Embodiment 1, it has excellent mass productivity. In addition, the high material utilization efficiency reduces manufacturing costs, making it a low-cost light-emitting device. The device can be obtained.

[0253] FIG. 9 shows an example in which a light emitting device to which the present invention is applied is used as an indoor lighting device 3001. The light-emitting device of the present invention can be made large in area, and therefore can be used as a large-area lighting device. In addition, the light emitting device of the present invention is thin and consumes low power. In this way, the light-emitting device to which the present invention is applied can be used as a lighting device for the In the room used as the indoor lighting device 3001, the present invention as described with reference to FIG. By installing such a television set, public broadcasting and movies can be enjoyed. The device consumes low power, so you can enjoy powerful images in a bright room without worrying about your electricity bill. You can award it. EXAMPLES

[0254] <Synthesis Example 1> In this Synthesis Example 1, the organometallic compound of the present invention represented by the structural formula (147) shown in the first embodiment is Complex, bis(2,3,5-triphenylpyrazinate)(dipivaloylmethanato)iridium A specific example of the synthesis of Ir(tppr)2(dpm) is given below. .

[0255] [ka]

[0256] <Step 1: Synthesis of 2,3,5-triphenylpyrazine (abbreviation: Htppr)> First, in a nitrogen atmosphere, a solution of phenyllithium in dibutyl ether (Wako Pure Chemical Industries, Ltd.) Mix 5.5 mL of 2.1 mol / L diethyl ether and cool on ice. 2.43 g of 2,3-diphenylpyrazine was added dropwise to this solution, and the mixture was stirred at room temperature for 24 hours. Water was added to this mixture, and the organic layer was extracted with diethyl ether. After washing with water, it was dried over magnesium sulfate. After drying, activated manganese dioxide was added to the solution. The excess was added and filtered. The solvent of this solution was distilled off, and the resulting residue was diluted with ethanol. The pyrazine derivative Htppr was obtained by recrystallization (yellow powder, 56% yield). The synthetic scheme of Step 1 is shown below (a-1).

[0257] [ka]

[0258] <Step 2; Di-μ-chloro-bis[bis(2,3,5-triphenylpyrazinate) Synthesis of [Iridium(III)] (abbreviation: [Ir(tppr)2Cl]2)> Next, the above-mentioned step was carried out using a mixture of 30 mL of 2-ethoxyethanol and 10 mL of water as a solvent. The pyrazine derivative Htppr obtained in step 1 was mixed with 1.08 g of iridium chloride hydrate (IrCl 0.73 g of 3·H2O (Sigma-Aldrich) was mixed and cooled in a nitrogen atmosphere. After refluxing for 16 hours, the precipitated powder was filtered and then washed with ethanol, diethyl ether, and then hexane. The dinuclear complex [Ir(tppr)2Cl]2 (orange color) was obtained by washing with xanthene. Powder, 97% yield). The synthesis scheme for step 2 is shown in (b-1) below.

[0259] [ka]

[0260] <Step 3; Bis(2,3,5-triphenylpyrazine)(dipivaloylmethanate) Synthesis of Iridium(III) (abbreviation: [Ir(tppr)2(dpm)]) 25 mL of 2-ethoxyethanol, the binuclear complex [Ir(tppr)2 Cl]20.40 g, dipivaloylmethane 0.14 mL, sodium carbonate 0.25 g The mixture was then placed in a recovery flask equipped with a reflux condenser, and the atmosphere in the flask was replaced with argon. The mixture was irradiated with microwaves (2.45 GHz, 150 W) for 15 minutes to react. The reaction solution was filtered. The filtrate was recrystallized from ethanol, and the resulting red powder was extracted with ethanol and then diethyl ether. The organometallic complex of the present invention [Ir(tppr)2(dp m)] was obtained (yield 75%). Microwave irradiation was performed using a microwave synthesis apparatus (CEM Corporation). The synthesis scheme of step 3 is shown in (c-1) below.

[0261] [ka]

[0262] The red powder obtained in step 3 was analyzed by nuclear magnetic resonance spectroscopy ( 1 H-NMR The analysis results are shown below. 1 The H NMR chart is shown in Figure 12. In Example 1, the organometallic complex of the present invention represented by the above structural formula (147) [Ir(tp pr)2(dpm)] was obtained.

[0263] 1 The H NMR is shown below. 1 H NMR.δ(CDCl3): 1.02(s,18H) ,5.64(s,1H),6.51(m,4H),6.64(m,2H),6.92(d ,2H),7.44-7.56(m,12H),7.80(brs,4H),8.06( d,4H),8.86(s,2H).

[0264] The decomposition temperature of the obtained organometallic complex of the present invention [Ir(tppr)2(dpm)] was High vacuum differential thermobalance (Bruker AXS, TG-DTA241 The temperature was increased at a rate of 10°C / min under normal pressure. At 327°C, a 5% weight loss was observed, indicating good heat resistance.

[0265] Next, the absorption spectrum of [Ir(tppr)2(dpm)] was measured. The measurement was performed using a UV-visible spectrophotometer (V550, manufactured by JASCO Corporation) with dichloromethane. The measurements were carried out at room temperature using a phosphate solution (0.094 mmol / L). The emission spectrum of the 2-(dpm) fluorescein was measured. (FS920, Hamamatsu Photonics, Inc.) was used, and a degassed dichloromethane solution (0.3 Measurements were performed at room temperature using a 100% ethanol solution (3 mmol / L). The excitation wavelength was 465 nm. The results are shown in Figure 13. The horizontal axis represents the wavelength, and the vertical axis represents the molar absorption coefficient and the emission intensity.

[0266] As shown in FIG. 13, the organometallic complex of the present invention [Ir(tppr)2(dpm)] has a molecular weight of 63 The emission peak was at 10 nm, and red emission was observed from the solution. EXAMPLES

[0267] In this example, the dissolution of an organometallic complex having a pyrazine skeleton as described in Embodiment 1 was performed. The solubility of the compound was evaluated by examining its solubility in various solvents. Alcohols 2-ethoxyethanol, isopropanol and ethanol, ethers Dioxane, which is an aromatic ring-free organic solvent, and chloroform and dimethylformamide, which are non-aromatic organic solvents. The solvents used were dichloromethane (DMF) and toluene, an aromatic hydrocarbon solvent.

[0268] As the organometallic complex having a pyrazine skeleton, among the complexes disclosed in the first embodiment, [Ir(tppr)2(dpm)] represented by structural formula (147) synthesized in Example 1 was evaluated. It was selected as a target and its solubility was investigated.

[0269] [ka]

[0270] The solubility test results of the samples are shown in Table 1 below. In Table 1, the solubility x (g / L) is less than x If x is 0.6, use a cross; if x is 0.9>x>0.6, use a triangle; if x is 1.2>x>0.9, use a circle. , x≧1.2 are indicated by double circles.

[0271] [Table 1]

[0272] [Ir(tppr)2(dpm)] represented by structural formula (147) synthesized in Example 1 is It is highly soluble in alcohols such as 2-ethoxyethanol, isopropanol and ethanol. In particular, 2-ethoxyethanol showed sufficiently high solubility (0.6 g / L or more). It was found that schietenol has a very high solubility (1.2 g / L or more). Therefore, the composition is suitable for use as a coating composition in a light-emitting device produced by a wet process.

[0273] In addition, [Ir(tppr)2(dpm)] represented by structural formula (147) is an ether. It was also found that it has extremely high solubility (1.2 g / L or more) in dioxane, which is a In addition, organic solvents that do not have an aromatic ring, such as chloroform and dimethylformamide (DMF), It can be seen that it also shows very high solubility (1.2 g / L or more) in MF. In addition, it has a sufficiently high solubility in toluene, an aromatic hydrocarbon solvent (0.6 g / L). Therefore, the compound represented by the structural formula (147) [Ir(tppr)2(dpm) ] is soluble in many types of solvents and is therefore suitable for use in coating compositions.

[0274] In this way, the introduction of the ligand represented by the general formula (L1) increases the solubility. In particular, the present inventors have found that the above-mentioned reaction is effective in a solvent that does not have an aromatic ring (e.g., alcohols). The phenomenon of increased solubility in water can be said to be very distinctive. EXAMPLES

[0275] In this embodiment, a light-emitting element using an organometallic complex of the present invention will be described.

[0276] <Preparation of solution A> First, bis(2-methyl-8-oxopropanediol) was added to 20 mL of 2-methoxyethanol (Kanto Chemical). (4-phenylphenolato)aluminum(III) (manufactured by Chemipro Chemicals, Noboru 0.305g of BAlq (abbreviation: BAlq), 0.305g of N,N'-bis(3-methylphenyl) -N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (manufactured by Tokyo Chemical Industry Co., Ltd.) ) (abbreviation: TPD) 0.0151 g, Ir(tppr)2(dpm 0.029 g of 1,2-dichlorophenyl ether was dissolved in the solution A containing the organometallic complex of the present invention. A was bubbled with argon for 1 hour to remove oxygen just before spin coating. The sample bottle was placed in an oven ( The structural formulas of BAlq, TPD, and Ir(tppr)2(dpm) are as follows: As shown below.

[0277] [ka]

[0278] <Preparation of solution B> In 40 mL of 1,4-dioxane (dehydrated) (Kanto Chemical), polyvinylcarbazole (A 0.10 g of 4,4'-bis(PVK, Mw=1100000, manufactured by Rudrich) [N-(1-naphthyl)-N-phenylamino]biphenyl (Chemipro Chemicals, sublimation purified product) ) (abbreviation: NPB) was dissolved in 0.0255 g to prepare solution B. The structural formula of NPB is shown below.

[0279] [ka]

[0280] <Fabrication of Light-emitting Device 1> First, a glass substrate was coated with a 110 nm thick indium tin silicon oxide (ITSO) film. The ITSO surface was exposed with a 2 mm square surface surrounded by polyimide. The ITSO layer functions as the anode of the light-emitting element. As a pretreatment for forming the compound, water and 2-ethoxyethanol were mixed in a volume ratio of 3:2. The mixed solution was dropped onto ITSO and spin-coated.

[0281] Next, 15 mL of PEDOT / PSS (Starck, AI4083sp.gr) and 2- A mixed solution was prepared by mixing 10 mL of ethoxyethanol, and this mixed solution was placed on ITSO. Immediately after, the mixture was rotated at 2000 rpm for 60 seconds, then at 3000 rpm for 60 seconds. The substrate was spin-coated for 10 seconds. In addition, the edge of the substrate was wiped and the terminal connected to the ITSO was After exposure, bake for 2 hours at 110°C in a vacuum dryer with reduced pressure using a rotary pump. A hole injection layer, PEDOT / PSS, was formed on the ITSO. The thickness was 50 nm. I did.

[0282] Next, the previously prepared solution B was poured onto the PEDOT / PSS in a glove box (oxygen concentration The temperature was 20 ppm or less, and the moisture concentration was 5 ppm or less. First, run it at 300 rpm for 2 seconds, then run it at 2000 rpm for 60 seconds. The test was performed for 10 seconds at a rotation speed of 2500 rpm. The edge of the substrate was then wiped and attached to ITSO. The terminals connected to the board were then exposed. After that, the board was placed in a vacuum dryer with the pressure reduced by a rotary pump. The solution was dried in a vacuum at 120°C for 1 hour to form a hole transport layer. The film was formed on a glass substrate under the above film formation conditions, and a surface profile measuring device (ULVAC, DEK When measured using a TAK V200Si, the film thickness was 15 nm.

[0283] Next, the substrate on which the PEDOT / PSS and PVK / NPB films were formed was exposed to the air. The environment inside the glove box (oxygen concentration 10 ppm or less, moisture concentration 2 ppm or less) The hole transport layer was then spin-coated with solution A. 0 rpm for 2 seconds, then 500 rpm for 60 seconds, and The test was performed at a rotation speed of 100 rpm for 10 seconds. In addition, the edge of the board was wiped and connected to the ITSO. The terminals were then exposed. After that, the device was placed in a vacuum dryer with a rotary pump at a reduced pressure for 100 The solution was dried in vacuum at 37°C for 1 hour to form a light-emitting layer. A film was formed on a glass substrate under the film conditions, and a surface profile measuring device (ULVAC, DEKTAK V2 00Si), the film thickness was 40 nm.

[0284] Next, the above substrate is placed in a vacuum deposition apparatus without being exposed to the atmosphere, and a light-emitting layer is formed. The substrate was fixed to a holder provided in a vacuum deposition apparatus so that the coated surface faced downward.

[0285] The vacuum deposition equipment was -4 After reducing the pressure to 10 Pa, bis(2-methyl-8-quinolinolato) (4-phenylphenol)aluminum(III) (abbreviation: BAlq) is evaporated to 10 nm A first electron transport layer was formed by this. A second electron transport layer was formed by depositing 20 nm of phenanthroline (BPhen). Furthermore, lithium fluoride (LiF) was evaporated to a thickness of 1 nm on the second electron transport layer. Finally, an electron injection layer was formed by depositing aluminum to a thickness of 200 nm as a cathode. In the above-mentioned deposition process, deposition was performed using a resist. The thermal decomposition method was used. The structural formula of BPhen is shown below.

[0286] [ka]

[0287] <Operation characteristics of light-emitting element 1> The light-emitting element 1 obtained as described above is placed in a glove box with a nitrogen atmosphere. After sealing the device so that it is not exposed to the atmosphere, the operating characteristics of this light-emitting device were The measurements were carried out at room temperature (an atmosphere maintained at 25°C).

[0288] FIG. 14 shows an emission spectrum when a current of 1 mA was applied to the light-emitting element 1.

[0289] Light-emitting element 1 has a luminance of 1025 cd / m 2 The CIE chromaticity coordinates are (x=0.66, y =0.34) and emitted red light. The luminance was 1025cd / m 2 Current when The efficiency was 3.2cd / A. The brightness was 1025cd / m 2 The voltage is 12.0 V, current density is 31.9mA / cm 2 and the power efficiency was 0.8lm / W. As shown in FIG. 14, the emission peak wavelength was 618 nm.

[0290] From the above, by applying the present invention, a light-emitting element with high luminous efficiency can be obtained. It can be seen that.

[0291] In addition, by using the composition of the present invention, a wet process can be further performed on a layer containing an organic compound. In particular, as shown in this embodiment, the layer can be formed using alkoxide. A layer that is insoluble in alcohol (a hole transport layer in this embodiment) is formed by a wet method, and then an aluminum alloy is applied thereon. By applying the composition of the present invention using alcohol by a wet method, lamination by a wet method can be achieved. Therefore, the method for producing a light-emitting element using the composition of the present invention is excellent in mass productivity, It is suitable for industrialization, and the efficiency of material utilization is high, which reduces manufacturing costs. EXAMPLES

[0292] <Synthesis Example 2> In this Synthesis Example 2, the organometallic compound of the present invention represented by the structural formula (148) shown in the first embodiment is Complex, bis(2,3,5-triphenylpyrazine)(pivaloyltrifluoroacetonate Here is an example of the synthesis of iridium(III) (abbreviation: [Ir(tppr)2(pFac)]). To give a concrete example.

[0293] [ka]

[0294] <Bis(2,3,5-triphenylpyrazine)(pivaloyltrifluoroacetonate) Synthesis of Iridium(III) (abbreviation: [Ir(tppr)2(pFac)]) 25 mL of 2-ethoxyethanol, the binuclear complex obtained in step 2 of the above-mentioned Synthesis Example 1 [ Ir(tppr)2Cl]20.45g, pivaloyltrifluoroacetone 0.14m Put 0.29 g of sodium carbonate into a recovery flask equipped with a reflux condenser, and heat the flask to 1000°C. After that, it was irradiated with microwaves (2.45 GHz, 100 W) for 20 minutes. Dichloromethane was added to the reaction solution, which was then filtered. The filtrate was concentrated to give an orange color. A colored powder was precipitated. This powder was collected by filtration and washed with ethanol and then with ether. The organometallic complex of the present invention, [Ir(tppr)2(pFac)], was obtained (yield 76%). The synthetic scheme for this step is shown in (c-2) below.

[0295] [ka]

[0296] The orange powder obtained in the above step was analyzed by nuclear magnetic resonance spectroscopy ( 1 Analysis by H-NMR The results are shown below. 1 The H-NMR chart is shown in Figure 15. In Example 2, the organometallic complex of the present invention represented by the above structural formula (148) [Ir(tpp r)2(pFac)] was obtained.

[0297] 1 H-NMR.δ(CDCl3):1.06(s,9H),5.88(s,1H),6. 45(d,2H),6.54(dt,2H),6.67(m,2H),6.92(d,2 H),7.48-7.57(m,12H),7.82(m,4H),8.08(ddd, 4H), 8.75(s,1H), 8.92(s,1H).

[0298] Next, the absorption spectrum of [Ir(tppr)2(pFac)] was measured. The measurement was performed using a UV-visible spectrophotometer (V550, manufactured by JASCO Corporation) with dichloromethane. The measurements were carried out at room temperature using a phosphate solution (0.090 mmol / L). The emission spectrum of the 2-amino-p-Fac complex was measured. A degassed dichloromethane solution (0. The measurement was performed at room temperature using a 100% alcohol (31 mmol / L). The measurement results are shown in Figure 16. The horizontal axis is the wave The long and long axes represent the molar extinction coefficient and the emission intensity.

[0299] As shown in FIG. 16, the organometallic complex of the present invention [Ir(tppr)2(pFac)] has a molecular weight of 61 The emission peak was at 10 nm, and orange emission was observed from the solution. EXAMPLES

[0300] In this example, the dissolution of an organometallic complex having a pyrazine skeleton as described in Embodiment 1 was performed. The solubility of the compound was evaluated by examining its solubility in various solvents. dioxane, an aromatic ether, and chloroform and dimethylform, organic solvents without aromatic rings. The solvents used were dichloromethane (DMF) and toluene, an aromatic hydrocarbon solvent.

[0301] As the organometallic complex having a pyrazine skeleton, among the complexes disclosed in the first embodiment, [Ir(tppr)2(pFac)] represented by structural formula (148) synthesized in Example 4 was evaluated. was selected as a valence object and its solubility was investigated.

[0302] [ka]

[0303] The solubility test results of the samples are shown in Table 2 below. In Table 2, the solubility x (g / L) is less than x If x is 0.6, use a cross; if x is 0.9>x>0.6, use a triangle; if x is 1.2>x>0.9, use a circle. , x≧1.2 are indicated by double circles.

[0304] [Table 2]

[0305] [Ir(tppr)2(pFac)] represented by structural formula (148), synthesized in Example 4 has high solubility and is suitable for use in a coating composition for a light-emitting device fabricated by a wet process.

[0306] Specifically, [Ir(tppr)2(pFac)] represented by structural formula (148) is It also has extremely high solubility (1.2 g / L or more) in dioxane, an ether. In addition, organic solvents that do not have an aromatic ring, such as chloroform and dimethylformamide, It was also found that it exhibits extremely high solubility (1.2 g / L or more) in dichloromethane (DMF). It also has very high solubility in toluene, an aromatic hydrocarbon solvent (1. 2g / L or more). Therefore, [Ir(tppr) 2(pFac)] is soluble in many types of solvents and is therefore suitable for use in coating compositions. be.

[0307] In this way, the introduction of the ligand represented by the general formula (L1) increases the solubility. The present inventors have found that. [Explanation of symbols]

[0308] 100 Substrates 101 First electrode 102 Second electrode 103 EL layer 111 Hole injection layer 112 Hole transport layer 113 Light-emitting layer 114 Electron transport layer 115 Electron injection layer 501 First electrode 502 Second electrode 511 First Light Emitting Unit 512 Second Light Emitting Unit 513 Charge generation layer 601 Drive circuit section (source side drive circuit) 602 Pixel section 603 Drive circuit section (gate side drive circuit) 604 Sealing substrate 605 Sealing material 607 Space 608 Wiring 609 FPC (Flexible Printed Circuit) 610 Element Substrate 611 Switching TFT 612 Current Control TFT 613 First electrode 614 Insulation 616 EL layer 617 Second Electrode 618 Light-emitting element 623 N-channel TFT 624 P-channel TFT 713 First Electrode 714 Insulating layer 716 Layer containing organometallic complex 717 Second Electrode 718 Light-emitting element 719 Insulating layer 730 Droplet discharge device 731 Droplet 732 Layer containing composition 901 Case 902 Liquid crystal layer 903 Backlight 904 Case 905 Driver IC 906 Terminal 951 Board 952 Electrode 953 Insulation Layer 954 Partition layer 955 EL layer 956 Electrode 1400 Board 1403 Droplet discharge means 1404 Imaging means 1405 Head 1406 Dotted Line 1407 Control means 1408 Storage medium 1409 Image processing means 1410 Computer 1411 Marker 1412 Head 1413 Material Source 1414 Material Source 2001 Case 2002 light source 3001 Lighting equipment 9101 Case 9102 Support stand 9103 Display section 9104 Speaker section 9105 Video input terminal 9201 Main unit 9202 Case 9203 Display section 9204 Keyboard 9205 External connection port 9206 Pointing Device 9401 Main unit 9402 Case 9403 Display section 9404 Audio input section 9405 Audio output unit 9406 Operation key 9407 External connection port 9408 Antenna 9501 Main unit 9502 Display section 9503 Case 9504 External connection port 9505 Remote control receiver 9506 Image receiving unit 9507 Battery 9508 Audio input section 9509 Operation key 9510 Eyepiece

Claims

[Claim 1] A light-emitting material comprising an organometallic complex represented by formula (G1): 【Chemistry 1】 (In the formula, Ar represents a substituted or unsubstituted arylene group. R １ represents either an alkyl group or a substituted or unsubstituted aryl group. ２ represents either hydrogen, an alkyl group, or a substituted or unsubstituted aryl group. ３ represents either hydrogen or an alkyl group. ２ and R ３ may be bonded to each other to form an alicyclic ring. M is a central metal and represents either a Group 9 element or a Group 10 element. When the M is a Group 9 element, n=2, and when the M is a Group 10 element, n=1. ２１ and R ２２ one represents an alkyl group or a haloalkyl group having 2 to 10 carbon atoms, and the other represents an alkyl group or a haloalkyl group having 1 to 10 carbon atoms; R ２１ and R ２２ are each a branched alkyl group.

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