WO2004069800A1

WO2004069800A1 - Polynuclear organometallic complexes, organic el devices and organic el displays

Info

Publication number: WO2004069800A1
Application number: PCT/JP2003/001372
Authority: WO
Inventors: Tasuku Satoh; Wataru Sotoyama; Norio Sawatari
Original assignee: Fujitsu Limited
Priority date: 2003-02-10
Filing date: 2003-02-10
Publication date: 2004-08-19
Also published as: AU2003207201A1

Abstract

The invention provides organic EL devices which are made by using polynuclear organometallic complexes as the luminescent material and are excellent in lifetime, luminous efficiency, and so on, specifically an organic EL device comprising a positive electrode, a negative electrode, and an organic thin film placed between the electrodes, wherein the organic thin film contains a polynuclear organometallic complex which is composed of Group IB metal atoms, ligands each having at least one π-conjugated moiety and coordinating to the metal atoms, and halogen atoms connecting the metal atoms by bridging. It is preferable that the polynuclear organometallic complex be one represented by the structural formula (1).

Description

TECHNICAL FIELD The present invention relates to an organometallic dinuclear complex suitable as a light emitting material in an organic EL device, an organic EL device using the organometallic dinuclear complex, and the organic EL device. The present invention relates to an organic EL display using an EL element. BACKGROUND ART Organic EL devices have features such as self-emission and high-speed response, and are expected to be applied to flat panel displays. In particular, organic thin films (hole transport layers) with hole transport properties and electron transport Since the two-layer type (laminated type) in which an organic thin film (electron transport layer) is laminated (for example, see Non-Patent Document 1), large-area light emission that emits light at a low voltage of 1 OV or less has been reported. It is gaining interest as an element. The stacked organic EL device has a basic structure of a positive electrode / a hole transport layer / a light emitting layer / an electron transport layer / a negative electrode, wherein the light emitting layer is the same as the hole transport layer or the two-layer type. The electron transport layer may have the same function.

The principle of light emission in the organic EL element is that when a voltage is applied between both electrodes, electrons are injected from the negative electrode side, holes are injected from the positive electrode side, and electrons are injected into the light emitting layer. This is a phenomenon in which light is emitted when the light emitting material of the light emitting layer is deactivated from the excited state to the ground state.

Organic EL devices are recently expected to be applied to full-color displays. In the full-color display, it is necessary to arrange pixels that emit light of three primary colors of blue (B), green (G), and red (R) on a panel. ), Green (G), and red (R) light emission methods. (B) White light emission (blue (B), green (G), and red (R) light (C) Separating the light emission from the organic EL device that emits blue light into the three primary colors using a color filter. A method has been proposed in which a color conversion layer using fluorescent light emission converts the light into green (G) and red (R) light.

On the other hand, from the viewpoint of obtaining an organic EL device with high luminous efficiency, a host material, which is a main material, is doped with a small amount of a dye molecule having high fluorescent luminescence as a guest material to form a luminescent layer exhibiting high luminous efficiency. (For example, see Non-Patent Document 2).

Although stability and lifetime are important performances for organic EL devices, they have not been sufficiently studied in comparison with performances such as luminous efficiency. Recently, it has been gradually revealed that the organic EL element is degraded by various factors, for example, thermal factors, electrochemical factors, factors due to interface phenomena, and the like. It is being proposed. However, at present, there is no conventional organic EL device that simultaneously and highly satisfies the luminous efficiency, the life and the stability.

Non-patent document 1

C. W. Tang and S. A. Van Slyke, Applied Physics Letters vol. 51, 913 (198

7)

Non-patent document 2

CW Tang, SA VanSlyke, and CH Chen, Journal of Applied Physics vol. 65, 3610 (1989) An object of the present invention is to solve the conventional problems and achieve the following objects. That is, the present invention provides an organometallic dinuclear complex suitable as a light-emitting material in an organic EL device, and an organic EL using the organometallic dinuclear complex, which has excellent thermal and electrical stability, and is excellent in lifetime, luminous efficiency, and the like. It is an object of the present invention to provide a device and an organic EL display having a high performance and a long life using the organic EL device. DISCLOSURE OF THE INVENTION The organometallic dinuclear complex of the present invention is obtained by crosslinking at least two Group 1 metal elements in which a ligand having at least one π-conjugated moiety is coordinated and bonded with a halogen atom. It is characterized by being used for. In the organometallic dinuclear complex, The emission wavelength can be changed and adjusted by appropriately changing the number and type of the ligand, the group 1B metal element and the halogen atom, and the desired red emission, green emission, blue emission, and the like can be obtained. can get. Further, since the organometallic dinuclear complex coordinates the ligand, it has excellent overall thermal and electrical stability. When the organometallic dinuclear complex is used as a light-emitting material in an organic EL device, light emission with excellent lifetime, luminous efficiency, and the like can be obtained. The organic EL device of the present invention has an organic thin film layer between a positive electrode and a negative electrode, and the organic thin film layer is a group 1 metal having a ligand coordinated with at least one π-conjugated moiety. It contains, as a light-emitting material, an organometallic dinuclear complex in which at least two of the elements are crosslinked by a halogen atom. Since the organic EL device * 5 contains the organometallic dinuclear complex of the present invention as a light emitting material, it has excellent thermal and electrical stability, and has excellent lifetime and luminous efficiency. An organic EL display of the present invention is characterized by using the organic EL element of the present invention. Since the organic EL display uses the organic EL element of the present invention, the organic EL display is excellent in thermal and electrical stability, and is excellent in lifetime, luminous efficiency, and the like. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic explanatory view for explaining an example of a layer configuration in an organic EL device of the present invention.

FIG. 2 is a schematic explanatory view for explaining a structural example of a passive matrix organic EL display (passive matrix panel).

FIG. 3 is a schematic diagram for explaining a circuit in the passive matrix organic EL display (passive matrix panel) shown in FIG.

FIG. 4 is a schematic explanatory diagram for explaining an example of the structure of an active matrix type organic EL display (active matrix panel).

FIG. 5 is a schematic diagram for explaining a circuit in the active matrix organic EL display (active matrix panel) shown in FIG. BEST MODE FOR CARRYING OUT THE INVENTION

(Organometallic dinuclear complex)

The organometallic dinuclear complex of the present invention has a structure in which at least two of Group 1 metal elements in which a ligand having at least one π-conjugated moiety is coordinated and bonded are cross-linked by a halogen atom. Used for EL elements.

The organometallic dinuclear complex is not particularly limited as long as it has the above structure, and can be selected according to the purpose. For example, a complex represented by the following structural formula (1) is preferable. Π

Structural formula (1)

In the structural formula (1), M represents a Group 1B metal element. The group 1B metal element is a heavy metal that is extremely stable to oxygen, water, acid, and alkali metal, and is called a noble metal element, and examples thereof include Cu, Ag, and Au. At least two group IB metal elements M are contained in the organometallic dinuclear complex.

X represents a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

L is a ligand coordinated and bonded to the group 1B metal element M so as to satisfy the stable coordination number of the group 1B metal element M, and is a ligand having at least one π-conjugated moiety. Represent. Since the stable coordination number of the group 1 metal element is 4, the ligand L is selected such that the stable coordination number is 4, but the stable coordination number of this ligand is Also includes the number of halogen atoms bridging the Group 1 metal element. η represents the number of ligands L, and represents an integer of 1 to 2. By changing the number and type of the ligands L, the emission wavelength of the organometallic dinuclear complex can be changed as desired. The ligand L is not particularly limited and may be appropriately selected depending on the intended purpose.For example, an atom capable of monodentate or bidentate or more coordination bond with the group 1B metal element may be selected from an aromatic ring. Preferred examples include those partially contained. The atom is preferably selected from, for example, a nitrogen atom, an oxygen atom, a chalcogen (sulfur atom, selenium atom, tellurium atom, polonium atom) and a phosphorus atom.

Among the ligands L, a cyclic compound having a 1- to 6-membered aliphatic or aromatic ring containing a nitrogen atom is preferable. Specifically, for example, quinoline, pyridine, 2 , 2, 1-biviridine, derivatives thereof, and the like are preferable, and among these, those represented by the following structural formula are more preferable.

Pyridine quinoline 2,2'-biviridine In each of the above structural formulas, R ¹ represents one or more substituents each bonded to an arbitrary position of the cyclic structure, for example, a hydrogen atom, a halogen atom, an alkoxyl A group, an amino group, an alkyl group, a cycloalkyl group, an aryl group or an aryloxy group which may contain a nitrogen atom or a sulfur atom, which may be further substituted by a substituent. When the number of R ¹ is 2 or more, the R ¹ may be the same or different from each other, and are bonded to each other at any adjacent substitution position to form a nitrogen atom, a sulfur atom, or an oxygen. It may form an aromatic ring which may contain atoms, and these may be further substituted with a substituent. p represents an integer of 0 to 5.

In the structural formula (1), m represents an integer of 1 or more, preferably 1 to 200, and more preferably 1 to 50. When m is 1, the organometallic dinuclear complex is represented by the following structural formula (2). Ln

X M

Structural formula (2)

M iiiiiiiiiimiii X

Ln In the structural formula (2), M, X, L and n are the same as those in the structural formula (1).

Among the organometallic dinuclear complexes represented by the structural formula (2), those represented by the following structural formula are preferable.

\ \

Cu Cu

Further, in the structural formula (1), when the m is 2 or more, the n is preferably 1 or 2, and specifically, the one represented by the following structural formula is preferable.

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The organometallic dinuclear complex in the present invention also includes various derivatives of the organometallic dinuclear complex.

The method for producing the organometallic dinuclear complex of the present invention is not particularly limited, and can be appropriately selected from known methods according to the purpose. For example, J. Chem. Soc. Dalton The method described in Trans. 1986, 2303-2310 and the like are preferably exemplified. Specifically, for example, a halide (eg, CuI, CuCl, etc.) of the Group 1B metal element such as Cu, Ag, or Au, and a saturated aqueous solution of potassium iodide are mixed with a solvent (eg, acetone). ), Mix and stir. Here, a compound capable of coordinating with the group 1B metal element (for example, quinoline, pyridine, etc.) is added in an amount of X equivalent to the halide of the group 1B metal element. This mixed solution is refluxed for a certain period of time and then allowed to cool, whereby the organometallic dinuclear complex powder is precipitated. In this case, the molecular structure of the organometallic dinuclear complex can be appropriately adjusted depending on the amount of the compound capable of coordinating with the mixed group 1B metal element and the conditions for crystal precipitation after reflux.

The organometallic dinuclear complex of the present invention can be suitably used in various fields, but can be suitably used as a light emitting material in an organic EL device, and is particularly preferably used in the following organic EL device of the present invention. can do. When the organometallic dinuclear complex of the present invention is used as a light emitting material in the organic EL device of the present invention, red light emission is obtained. (Organic EL device)

The organic EL device of the present invention has an organic thin film layer between a positive electrode and a negative electrode, and the organic thin film layer contains the organometallic dinuclear complex of the present invention as a light emitting material.

In the present invention, the organometallic dinuclear complex is contained in the organic thin-film layer as a light-emitting material, but may be contained in the light-emitting layer of the organic thin-film layer, or as a light-emitting layer also serving as an electron transport layer and a light-emitting layer. It may be contained in a hole-transporting layer or the like. When the organometallic dinuclear complex is contained in the light-emitting layer, the light-emitting layer may be formed by forming a film using the organometallic dinuclear complex alone, or may contain other materials in addition to the organometallic dinuclear complex. May be formed.

In the present invention, the light-emitting layer, the light-emitting layer and the electron transport layer, the light-emitting layer and the hole transport layer, and the like in the organic thin film layer contain the organometallic dinuclear complex of the present invention as a guest material. Further, it is preferable to further contain a host material having an emission wavelength near the light absorption wavelength of the guest material. The host material is preferably contained in the light emitting layer, but may be contained in a hole transport layer, an electron transport layer, or the like.

When the guest material and the host material are used in combination, when the organic EL emission occurs, the host material is first excited. Then, since the emission wavelength of the host material and the absorption wavelength of the guest material (organometallic dinuclear complex) overlap, the excitation energy is efficiently transferred from the host material to the guest material, and the host material is Since only the guest material that has returned to the ground state without emitting light and is in the excited state emits excitation energy as light, it is excellent in luminous efficiency, color purity, and the like.

In general, when light-emitting molecules are present alone or in a high concentration in a thin film, the light-emitting molecules approach each other, causing an interaction between the light-emitting molecules. However, when the guest material and the host material are used in combination, since the organometallic dinuclear complex as the guest compound is dispersed in the host compound at a relatively low concentration, the “concentration quenching” is performed. Is effectively suppressed and the luminous efficiency is excellent. Furthermore, when the guest material and the host material are used together in the light emitting layer, the host material is generally excellent in film-forming properties, and thus is advantageous in that the light-emitting properties are maintained and the film forming properties are excellent.

The host material is not particularly limited and can be appropriately selected according to the purpose. The host material preferably has a light emission wavelength near the light absorption wavelength of the guest material. Examples include a molecular host material and a polymer host material.

The low-molecular host material is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include 4,4,1-bis (2,2,1-diphenylvinyl) _1,1,1-biphenyl. Nore (DP VB i), p-Seshikifenerinore (p-SP), 1, 3, 6, 8—Tetrafuerubirene (tppy), N, N, one dinaphthyl N, N, diphenyl 1 [1, [1,1-biphenyl] -14,4, diamine (NPD), oxine complex and carbazole derivative are preferred, and aromatic amine derivative represented by the following structural formula (3), 5) a carbazole derivative represented by the following formula, a oxine complex represented by the following structural formula (7), a 1,3,6,8-tetrafluorovinylene compound represented by the following structural formula (9), 11,4,1-bis (2,2'-diphenylvinyl) represented by 11) '-Biphenyl (DPVB i) (main emission wavelength = 470 nm), p-sesquiphenyl (main emission wavelength = 400 nm) represented by the following structural formula (12), and represented by the following structural formula (13) 9, one-bianthryl (main emission wavelength = 460 nm), and the like are more preferable.

R

A N Structural formula (3)

R n

In the structural formula (3), n represents an integer of 2 or 3. Ar represents a divalent or trivalent aromatic group or a heterocyclic aromatic group. R ² and R ³ may be the same or different, and represent a monovalent aromatic group or a heterocyclic aromatic group. The monovalent aromatic group or heterocyclic aromatic group is not particularly limited and can be appropriately selected depending on the purpose.

Among the aromatic amine derivatives represented by the structural formula (3), N, N, dinaphthyl N, N, diphenyl [1,1, -biphenyl] 1-4,4 represented by the following structural formula (4) '' Jiamin (NPD) (main emission wavelength = 430 nm) and its derivatives are preferred No.

Structural formula (4)

Structural formula (5)

Wherein in the structural formula (5), Ar, below, ^divalent or trivalent group containing an aromatic ring, or a divalent or trivalent group containing a heterocyclic aromatic ring.

These may be substituted with a non-conjugated group, and R represents a linking group, for example, preferably the following. C CF ゥ O

c- C s-

CCO In the structural formula (5), R ⁴ and R ⁵ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, an aryl group, a cyano group, an amino group, an acyl group, or an alkoxy group. Represents a carbonyl group, a carbonyl group, an alkoxy group, an alkylsulfonyl group, a hydroxyl group, an amide group, an aryloxy group, an aromatic hydrocarbon ring group, or an aromatic heterocyclic group, which are further substituted with a substituent. I'm sorry.

In the structural formula (5), n represents an integer, preferably 2 or 3.

Among the aromatic amine derivatives represented by the structural formula (5), Ar is an aromatic group in which two benzene rings are connected via a single bond, R ⁴ and R ⁵ are hydrogen atoms, n = 2, that is, selected from 4,4,1-bis (9_carbazolyl) -biphenyl (CBP) (main emission wavelength = 380 nm) represented by the following structural formula (6) and derivatives thereof Are preferred because they are particularly excellent in luminous efficiency and the like.

Structural formula (6)

Structural formula (7)

Here, in the structural formula (7), R ⁶ represents a hydrogen atom or a monovalent hydrocarbon group.

Among the oxine complexes represented by the structural formula (7), an aluminum quinoline complex (A1q) (main emission wavelength = 530 nm) represented by the following structural formula (8) is preferable.

Structural formula (8)

Alq

Structural formula (9)

However, in the structural formula (9), R ⁷ R ¹ . May be the same or different, and represent a hydrogen atom or a substituent. Preferred examples of the substituent include an alkyl group, a cycloalkyl group and an aryl group, and these may be further substituted with a substituent.

Among the 1,3,6,8-tetrafluorovinylenes represented by the structural formula (9), R ⁷ to ¹ ° is a hydrogen atom, that is, 1,3,6,8-tetraphenylene (main emission wavelength = 440 nm) represented by the following structural formula (10). .

Structural formula (10)

3, 6, 8-tetraphenylpyrene

Structural formula (11)

DPVB

Structural formula (12)

P-sexifenyl

9, 9'-Biantril structural formula (13)

The polymer host material is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include polyparaphenylene bulene (PPV), polythiophene (PAT), It is preferred to be selected from polyparaphenylene (PPP), polyvinylinole phenol (PVCz), polyfluorene (PF), polyacetylene (PA) and derivatives thereof.

PPV derivatives PAT derivatives PPP derivatives

PVCz derivatives In the above structural formula, R represents a hydrogen atom, a halogen atom, an alkoxy group, an amino group, an alkyl group, a cycloalkyl group, an aryl group which may contain a nitrogen atom or a sulfur atom, and an aryloxy group. And these may be further substituted with a substituent. X represents an integer. Among the polymer host materials, polyvinyl carbazole (PVC z) represented by the following structural formula (14) is preferable in terms of efficient transfer of excitation energy.

Structural formula (14)

In the structural formula (14), R ¹¹ and R ¹² each represent a plurality of substituents provided at arbitrary positions of the cyclic structure, and each independently represents a hydrogen atom, a logen atom, an alkoxy group, an amino group, Group, an alkyl group, a cycloalkyl group, an aryl group which may contain a nitrogen atom or a sulfur atom, and an aryloxy group, which may be further substituted with a substituent. In R ¹¹ and R ¹² , any adjacent substitution positions may be bonded to each other to form an aromatic ring which may contain a nitrogen atom, a sulfur atom, and an oxygen atom. May be further substituted with a group. X represents an integer.

The content of the organometallic dinuclear complex in the layer containing the organometallic dinuclear complex is preferably from 0.1 to 50% by mass, and more preferably from 0.5 to 20% by mass. No.

If the content is less than 0.1% by mass, the lifetime and the luminous efficiency may not be sufficient, and the content is 50% by mass. When the _ratio exceeds / ₀ , the color purity may be reduced. On the other hand, when the ratio is more preferable than the above range, it is preferable in that the life and the luminous efficiency are excellent.

The light emitting layer in the organic EL device of the present invention can inject holes from the positive electrode, the hole injection layer, the hole transport layer, and the like when an electric field is applied, and the negative electrode, the electron injection layer, and the electron transport layer And the like, and further provides a field of recombination between the holes and the electrons, and the recombination energy generated at the time of the recombination causes the organometallic dinuclear complex (light emission) to emit light. A material or a light-emitting molecule), and may contain other light-emitting materials other than the organometallic dinuclear complex within a range that does not impair the light emission. The light emitting layer can be formed according to a known method. Examples of the light emitting layer include a vapor deposition method, a wet film forming method, an MBE (molecular beam epitaxy) method, a cluster ion beam method, a molecular lamination method, an LB method, and a printing method. It can be preferably formed by a transfer method or the like.

Among them, the vapor deposition method is preferable because it can be easily and efficiently manufactured at low cost without using a waste liquid without using an organic solvent.However, when the light emitting layer is designed to have a single layer structure, For example, when the light emitting layer is formed as a hole transporting layer, a light emitting layer and an electron transporting layer, a wet film forming method is also preferable.

The evaporation method is not particularly limited and can be appropriately selected from known methods depending on the purpose.Examples include a vacuum evaporation method, a resistance heating evaporation method, a chemical evaporation method, a physical evaporation method, and the like. Examples of the chemical vapor deposition method include a plasma CVD method, a laser CVD method, a thermal CVD method, and a gas source CVD method. The formation of the light emitting layer by the vapor deposition method may be performed, for example, by vacuum-depositing the organometallic dinuclear complex, when the light emitting layer contains the host material in addition to the organometallic dinuclear complex, The co-evaporation of the complex and the host material by vacuum evaporation can be suitably performed. it can. The former case is easy to manufacture because no co-evaporation is required.

The wet film forming method is not particularly limited and may be appropriately selected from known ones according to the purpose. Examples thereof include an inkjet method, a spin coating method, a kneading method, a bar coating method, and a coating method. Method, casting method, dip method, curtain coating method and the like.

In the case of the wet film forming method, a solution in which the material of the light emitting layer is dissolved or dispersed together with a resin component can be used (applied or the like). As the resin component, for example, polybutyl rubazole, polycarbonate, or poly Vinyl chloride, polystyrene, polymethyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose, cellulose acetate, ABS resin, polyurethane, melamine resin, unsaturated polyester resin, Alkyd resins, epoxy resins, silicone resins, and the like.

The formation of the light emitting layer by the wet film forming method is performed, for example, by using a solution (coating solution) of the organometallic dinuclear complex and the resin material to be used as necessary as a solvent (coating and drying). When the light-emitting layer contains the host material in addition to the organometallic dinuclear complex, a solution (coating solution) is prepared by dissolving the organometallic dinuclear complex, the host material, and the resin material used as required in a solvent. The use (application and drying) can be suitably performed.

The thickness of the light emitting layer is preferably from 1 to 50 nm, more preferably from 3 to 20 nm.

When the thickness of the light emitting layer is within the preferred numerical range, luminous efficiency, light emission luminance, and color purity of light emitted by the organic EL device are sufficient, and when the thickness is within the more preferred numerical range, the effect is conspicuous. It is advantageous in certain respects.

The organic EL device of the present invention has an organic thin film layer including a light emitting layer between a positive electrode and a negative electrode, and may have another layer such as a protective layer depending on the purpose.

The organic thin film layer has at least the light emitting layer, and further has a hole injection layer, a hole transport layer, a hole blocking layer, an electron transport layer, an electron injection layer, and the like, if necessary. Yeah.

—Positive electrode _ The positive electrode is not particularly limited and may be appropriately selected depending on the intended purpose. The organic thin film layer, specifically, when the organic thin film layer has only the light emitting layer, the light emitting layer When the organic thin film layer further has the hole transport layer, the hole transport layer is provided. When the organic thin film layer further has the hole injection layer, the hole transport layer is provided. Those capable of supplying holes (carriers) are preferred.

The material of the positive electrode is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include metals, alloys, metal oxides, electrically conductive compounds, and mixtures thereof. Among them, a material having a work function of 4 eV or more is preferable.

Specific examples of the material of the positive electrode include conductive metal oxides such as tin oxide, zinc oxide, indium oxide, and indium tin oxide (ITO); metals such as gold, silver, chromium, and nickel; Mixtures or laminates with metal oxides; inorganic conductive substances such as copper iodide and copper sulfide; organic conductive materials such as polyaniline, polythiophene and polypyrrole; and laminates of these with ITO, etc. Can be These may be used alone or in combination of two or more. Among these, conductive metal oxides are preferred, and ITO is particularly preferred from the viewpoints of productivity, high conductivity, transparency and the like.

The thickness of the positive electrode is not particularly limited and may be appropriately selected depending on the material and the like, but is preferably 1 to 500 nm, more preferably 20 to 200 nm.

The positive electrode is usually formed on a substrate made of glass such as soda lime glass or non-alkali glass, or a transparent resin.

When the glass is used as the substrate, the alkali-free glass or the soda-lime glass coated with a barrier coat such as silica is preferred from the viewpoint of reducing the ions eluted from the glass.

The thickness of the substrate is not particularly limited as long as the thickness is sufficient to maintain the mechanical strength. However, when glass is used as the substrate, the thickness is usually 0.2 mm or more, and 0.7 or more. mm or more is preferable.

The positive electrode may be formed, for example, by a vapor deposition method, a wet film formation method, an electron beam method, a sputtering method, a reactive sputtering method, an MBE (molecular beam epitaxy) method, a cluster-on-beam method, an ion plating method, a plasma polymerization method ( High-frequency excitation ion plating method), molecular lamination method, LB method, printing method, transfer method, chemical reaction method (sol-gel method, etc.) It can be suitably formed by the above-mentioned method such as a method of applying a dispersion of TO.

The positive electrode can be subjected to washing or other treatment to lower the driving voltage of the organic EL element or increase the luminous efficiency. As the other treatment, for example, when the material of the positive electrode is ITO, a UV-ozone treatment, a plasma treatment and the like are preferably exemplified.

One negative electrode

The negative electrode is not particularly limited and may be appropriately selected depending on the intended purpose. The organic thin film layer, specifically, when the organic thin film layer has only the light emitting layer, the light emitting layer In addition, when the organic thin film layer further has the electron transport layer, electrons are supplied to the electron transport layer, and when the organic thin film layer has an electron injection layer between the organic thin film layer and the negative electrode, electrons are supplied to the electron injection layer. Are preferred.

The material of the negative electrode is not particularly limited, and may be appropriately selected according to the adhesion between the layer or molecules adjacent to the negative electrode such as the electron transport layer and the light emitting layer, ionization potential, stability, and the like. Examples thereof include metals, alloys, metal oxides, electrically conductive compounds, and mixtures thereof.

Specific examples of the material of the negative electrode include Al metal (for example, Li, Na, K, Cs, etc.), alkaline earth metal (for example, Mg, Ca, etc.), gold, silver, lead, Aluminum, sodium-alloy alloys or their mixed metals, lithium-aluminum alloys or their mixed metals, magnesium-silver alloys or their mixed metals, rare earth metals such as indium and iturium, and their alloys, etc. Is mentioned.

These may be used alone or in combination of two or more. Among these, a material having a work function of 4 eV or less is preferable, and aluminum, a lithium-aluminum alloy or a mixed metal thereof, a magnesium silver alloy or a mixed metal thereof is more preferable.

The thickness of the negative electrode is not particularly limited and may be appropriately selected depending on the material of the negative electrode, but is preferably 1 to 100 nm, more preferably 20 to 200 nm. The negative electrode may be formed, for example, by a vapor deposition method, a wet film formation method, an electron beam method, a sputtering method, a reactive sputtering method, an MBE (molecular beam epitaxy) method, or a cluster ion beam. It can be suitably formed by the above-mentioned methods such as a method, an ion plating method, a plasma polymerization method (high-frequency excitation ion plating method), a molecular lamination method, an LB method, a printing method, and a transfer method.

When two or more materials are used in combination as the material of the negative electrode, the two or more materials may be simultaneously evaporated to form an alloy electrode or the like, or an alloy electrode or the like may be formed by depositing a previously prepared alloy. It may be formed.

The resistance values of the positive electrode and the negative electrode are preferably low, and are preferably several hundreds Ω / port or less.

One hole injection layer

The hole injection layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the hole injection layer has a function of injecting holes from the positive electrode when an electric field is applied. Is preferred.

The material for the hole injection layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the material include starburstamine represented by the following formula (4, 4,, 4,, -tris [3-Methylphenyl (phenyl) amino] triphenylamine: m—MTD AT A, copper phthalone anine, polyaniline and the like are preferred.

The thickness of the hole injection layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the thickness is preferably about 1 to 100 nm, and more preferably 5 to 50 nm. The hole injection layer may be formed, for example, by a vapor deposition method, a wet film formation method, an electron beam method, a sputtering method, a reactive sputtering method, a MBE (molecular beam epitaxy) method, a cluster ion beam method, an ion plating method, or a plasma deposition method. It can be suitably formed by the above-mentioned methods such as a synthesizing method (high-frequency excitation ion plating method), a molecular lamination method, an LB method, a printing method, and a transfer method.

—Hole transport layer—

The hole transport layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a layer having a function of transporting holes from the positive electrode when an electric field is applied is preferable.

The material of the hole transport layer is not particularly limited and may be appropriately selected depending on the purpose.Examples include an aromatic amine compound, carpazole, imidazole, triazole, oxazole, oxaziazole, polyarylalkane, pyrazoline, and virazolone. , Phenylenediamine, arylamine, amino-substituted chalcone, styrylanthracene, fluorenone, hydrazone, stilbene, silazane, styrylamine, aromatic dimethylidin compound, porphyrin compound, polysilane compound, poly (N-vinylcalpazole), aniline Examples include polymers, thiophene oligomers and polymers, conductive high molecular oligomers such as polythiophene and polymers, carbon films, and the like. When a material for the hole transport layer is mixed with the material for the light emitting layer to form a film, a hole transport layer and a light emitting layer can be formed.

These may be used alone or in combination of two or more. Among them, aromatic amine compounds are preferable. Specifically, TPD (N , N'-diphenyl N, N'-bis (3-methylphenyl)-[1,1, -biphenyl] -1,4, diamine; NPD (N, N, dinaphthinole N) represented by the following formula , N, jiphenyiru [1,1,1biphenyl] -1,4,4, jiamin) and the like are more preferable.

The thickness of the hole transport layer is not particularly limited and may be appropriately selected depending on the intended purpose. The thickness is usually 1 to 50 Onm, and preferably 10 to 10 Onm.

The hole transport layer can be formed, for example, by a vapor deposition method, a wet film formation method, an electron beam method, a sputtering method, a reactive sputtering method, a MBE (molecular beam epitaxy) method, a cluster ion beam method, an ion plating method, or plasma. It can be suitably formed by the above-mentioned methods such as a polymerization method (high-frequency excitation ion plating method), a molecular lamination method, an LB method, a printing method, and a transfer method.

One hole blocking layer

The hole blocking layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a layer having a function of blocking holes injected from the positive electrode is preferable.

The material of the hole blocking layer is not particularly limited, and can be appropriately selected depending on the purpose. When the organic EL device has the hole blocking layer, the holes transported from the positive electrode side are blocked by the hole blocking layer, and the electrons transported from the negative electrode pass through the hole blocking layer. To the light-emitting layer, the electrons efficiently recombine with the holes in the light-emitting layer. Therefore, the recombination of the holes and the electrons in the organic thin-film layers other than the light-emitting layer occurs. Bonding can be prevented, and light emission from the organometallic dinuclear complex, which is the target light emitting material, can be efficiently obtained, which is advantageous in terms of color purity and the like.

The hole blocking layer is preferably disposed between the light emitting layer and the electron transport layer.

The thickness of the hole blocking layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the thickness is usually about 1 to 500 nm, preferably 10 to 50 nm.

The hole blocking layer may have a single-layer structure or a laminated structure. The hole blocking layer may be formed, for example, by a vapor deposition method, a wet film formation method, an electron beam method, a sputtering method, a reactive sputtering method, an MBE (molecular beam epitaxy) method, a cluster ion beam method, an ion plating method, It can be suitably formed by the above-mentioned methods such as a plasma polymerization method (high frequency excitation ion plating method), a molecular lamination method, an LB method, a printing method, and a transfer method. The electron transport layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the electron transport layer include a function of transporting electrons from the negative electrode and a function of blocking holes injected from the positive electrode. Those having any of them are preferable.

The material of the electron transport layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a quinoline derivative such as the aluminum quinoline complex (A1q), an oxaziazole derivative, a triazonole derivative, and the like. Phenanthroline derivatives, perylene derivatives, pyridine derivatives, pyrimidine derivatives, quinoxaline derivatives, diphenylquinone derivatives, nitro-substituted fluorene derivatives, and the like. When the material for the electron transport layer is mixed with the material for the light emitting layer to form a film, an electron transport layer and a light emitting layer can be formed. When the material for the hole transport layer is further mixed, the film is formed. An electron-transport layer and a hole-transport layer and a light-emitting layer can be formed. Polymers such as -ponates can be used.

The thickness of the electron transport layer is not particularly limited and may be appropriately selected depending on the purpose. For example, the thickness is usually about 1 to 500 nm, and preferably 10 to 50 nm. The electron transport layer may have a single-layer structure or a multilayer structure.

In this case, as the electron transporting material used in the electron transporting layer adjacent to the light emitting layer, an electron transporting material having a shorter light absorption edge than the above-mentioned organometallic dinuclear complex may be used. This is preferable from the viewpoint of limiting the light emitting region to the light emitting layer and preventing unnecessary light emission from the electron transport layer. Examples of the electron transporting material having a shorter light absorption edge than the organometallic dinuclear complex include a phenanthone-containing phosphorus derivative, an oxaziazole derivative, and a triazole derivative, and are represented by the following structural formula (15). Preferable examples include 2,9-dimethyl-14,7-diphenyl_1,10-phenanthroline (BCP) and the following compounds.

Structural formula (15)

2- (4-tert-butylphenyl) -5- (4-biphenylyl)

-1,3,4-oxaziazole

3-phenyl-4- (1-naphthyl)

-5-Phenyl-1,2,4-triazole

3- (4-tert-butylphenyl) -4-phenyl

-5-(4'-biphenyl) -1,2,4 -triazolyl

The electron transport layer may be formed, for example, by a vapor deposition method, a wet film formation method, an electron beam method, a sputtering method, a reactive sputtering method, an MBE (molecular beam epitaxy) method, a cluster-on-beam method, an ion plating method, or a plasma. It can be suitably formed by the above-mentioned methods such as a polymerization method (high-frequency excitation ion plating method), a molecular lamination method, an LB method, a printing method, and a transfer method.

One electron injection layer—

The electron injection layer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a layer having a function of injecting electrons from the negative electrode and sending the electrons to the electron transport layer. preferable.

The material for the electron injection layer is not particularly limited and can be appropriately selected depending on the intended purpose. For example, alkali metal fluorides such as lithium fluoride and strontium fluoride And other earth metal fluorides.

The thickness of the electron injection layer is not particularly limited and can be appropriately selected depending on the purpose. For example, the thickness is usually about 0.1 to 10 nm, and preferably 0.5 to 2 nm. The electron injection layer may be formed, for example, by a vapor deposition method, a wet film formation method, an electron beam method, a sputtering method, a reactive sputtering method, an MBE (molecular beam epitaxy) method, a cluster ion beam method, an ion plating method, a plasma polymerization method ( A high-frequency excitation ion plating method), a molecular lamination method, an LB method, a printing method, a transfer method, and the like can be suitably formed.

—Other layers

The organic EL device of the present invention may have other layers appropriately selected according to the purpose. Examples of the other layers include a protective layer and the like.

As the protective layer is not particularly limited, the force ^s that can be appropriately selected depending on the purpose, for example, the molecules or substances which promote deterioration of the organic EL elements such as moisture and oxygen from entering the organic EL device Are preferred.

The material of the protective layer, for example, I n, Sn, Pb, Au, Cu, Ag, A and T i, metals such as N i, MgO, S i O , S i 0 2, A 1 2 0 3 , GeO, N i O, C a 0, B a 0, F e 2 0 3, Y 2 0 3, T i 0 metal oxides such as _2, S i N, nitrides such as S i N _x O _y _{, MgF 2, L i F,} Al F 3, Ca F 2 metal fluorides such as, polyethylene having, polypropylene, polymethylmethacrylate, polyimide, polyurea, Po retainer trough Honoré O b ethylene, polyclonal port Torifunoreo port ethylene, poly Copolymer obtained by copolymerizing dichlorodifluoroethylene, a copolymer of ethylene with trichloroethylene and ethylene with dichlorodiphthalone, and a monomer mixture containing tetrafluoroethylene and at least one comonomer , A fluorine-containing copolymer having a cyclic structure in the copolymer main chain, water absorption of 1% or more Water-absorbing substances with a water absorption of 0.1% or less.

The protective layer may be formed, for example, by a vapor deposition method, a wet film formation method, a sputtering method, a reactive sputtering method, an MBE (molecular beam epitaxy) method, a cluster ion beam method, an ion plating method, or a plasma polymerization method (high frequency excitation ion plating). Method), a printing method, a transfer method, and the like. The structure of the organic EL device of the present invention is not particularly limited and may be appropriately selected depending on the purpose. Examples of the layer structure include the following layer structures (1) to (13), (1) positive electrode / hole injection layer hole transport layer / light emitting layer Z electron transport layer Z electron injection layer / negative electrode; (2) positive electrode Z hole injection layer Z hole transport layer Z light emitting layer / electron transport Layer / negative electrode, (3) positive electrode / hole transport layer Z light emitting layer / electron transport layer / electron injection layer negative electrode, (4) positive electrode / hole transport layer / light emitting layer / electron transport layer negative electrode, (5) positive electrode / positive (6) Positive electrode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / negative electrode, (7) Positive hole / hole transport layer / electron transport layer / electron injecting layer / negative electrode (8) Positive electrode / Hole transport layer / Electron transport layer / Electron transport layer / Negative electrode; (9) Positive electrode / Hole injection layer / Positive electrode Hole transport layer and light emitting layer / Electron transport layer / Electron injection layer / Anode (10) Positive electrode / hole injection layer / hole transport layer / light emitting layer Z electron transport layer / negative electrode, (11) Positive electrode / hole transport layer / light emitting layer / electron transport layer / electron injection layer / negative electrode, (12) Positive electrode / hole transport layer / light emitting layer / electron transport layer / negative electrode; (13) Positive electrode / hole transport layer / light emitting layer / electron transport layer / negative electrode;

In the case where the organic EL element has the hole blocking layer, in any of the above (1) to (13), a layer in which the hole blocking layer is disposed between the light emitting layer and the electron transport layer. The configuration is preferably exemplified.

Among these layer configurations, FIG. 1 shows an embodiment of the above (4) positive electrode hole transport layer, light emitting layer, Z electron transport layer, and negative electrode. The organic EL element 10 is formed on a glass substrate 12. A positive electrode 14 (for example, an ITO electrode), a hole transport layer 16, a light-emitting layer 18, an electron transport layer 20, and a negative electrode 22 (for example, an A1-Li electrode). Having. The positive electrode 14 (for example, an ITO electrode) and the negative electrode 22 (for example, an A 1 -Li electrode) are connected to each other via a power supply. An organic thin film layer 24 for emitting red light is formed by the hole transport layer 16, the light emitting layer 18, and the electron transport layer 20.

The emission peak wavelength of the organic EL device of the present invention is preferably from 600 to 650 nm. Regarding the luminous efficiency of the organic EL device of the present invention, it is desired that the organic EL device emits red light at a voltage of 10 V or less, preferably emits red light at a voltage of 7 V or less, and more preferably emits red light at a voltage of 5 V or less.

The emission luminance of the organic EL device of the present invention at an applied voltage of 10 V is preferably 100 cd / m ² or more, more preferably SOO cdZm ² or more. It is particularly preferred that it is at least 0.000 cd / m ² .

The organic EL device of the present invention includes, for example, a computer, an in-vehicle display, an outdoor display, a home appliance, a commercial appliance, a home appliance, a traffic display, a clock display, a power render display, and a luminescent display. Although it can be suitably used in various fields such as a cent screen, an acoustic device and the like, it can be particularly preferably used in the following organic EL display of the present invention.

(Organic)

The present invention EL display is not particularly limited except that the organic EL element of the present invention is used, and a known configuration can be appropriately adopted.

The organic EL display may be of a single-color emission type, of a multi-color emission type, or of a full-color type.

As a method of making the organic EL display a full-color type, for example, as described in “Monthly Display”, September 2000, pages 33 to 37, three primary colors (blue) are used. (B), green (G), and red (R)) OLEDs that emit light corresponding to each other are arranged on the substrate. There are known a white method that divides the light into three primary colors through a color filter, and a color conversion method that converts blue light emitted by an organic EL element for blue light emission into red (R) and green (G) through a fluorescent dye layer. In the present invention, the organic EL element of the present invention used is for red light emission.Thus, a three-color light-emitting method, a color conversion method, and the like can be preferably used, and a three-color light-emitting method is particularly preferably used. can do.

When a full-color organic EL display is manufactured by the three-color emission method, the organic EL element of the present invention is used for emitting red light, and in addition, an organic EL element for emitting green light and an organic EL for emitting blue light are used. Elements are required.

The organic EL device for emitting blue light is not particularly limited and can be appropriately selected from known devices. For example, the layer configuration is ITO (positive electrode) / NP DZA 1—Li (negative electrode) And the like are preferably mentioned.

The organic EL device for emitting green light is not particularly limited and may be appropriately selected from known devices. For example, the layer configuration is ITO (positive electrode) Z or NP DZ or A. 1q / A1—Li (negative electrode), and the like are preferably mentioned.

The mode of the organic EL display is not particularly limited and can be appropriately selected depending on the purpose. For example, “Nikkei Electronics”, No. 765, March 13, 2003 A passive matrix panel, an active matrix panel, and the like, as described in the Japanese Journal, pages 55-62, are preferred.

For example, as shown in FIG. 2, the passive matrix panel has strip-shaped positive electrodes 14 (for example, ITO electrodes) arranged on a glass substrate 12 in parallel with each other. A strip-shaped organic thin-film layer 24 for red light emission, an organic thin-film layer 26 for blue light emission, and an organic thin-film layer 28 for green light emission arranged in parallel to the cathode 14 and in a direction substantially perpendicular to the positive electrode 14, A negative electrode 22 having the same shape as these is provided on the organic thin film layer 24 for emitting red light, the organic thin film layer 26 for emitting blue light, and the organic thin film layer 28 for emitting green light.

In the passive matrix panel, for example, as shown in FIG. 3, a positive electrode line 30 composed of a plurality of positive electrodes 14 and a negative electrode line 32 composed of a plurality of negative electrodes 22 intersect each other in a substantially perpendicular direction. Thus, a circuit is formed. Each of the organic thin-film layers 24, 26, and 28 for red, blue, and green light located at each intersection functions as a pixel, and there are a plurality of organic EL elements 34 corresponding to each pixel. are doing. In the passive matrix panel, when a current is applied to one of the positive electrodes 14 on the positive electrode line 30 and one of the negative electrodes 22 on the negative electrode line 32 by the constant current source 36, at that time, an intersection is generated. A current is applied to the organic EL thin film layer located at the position, and the organic EL thin film layer at the position emits light. By controlling the light emission of each pixel, a full-color image can be easily formed.

The active matrix panel has, for example, scanning lines, data lines, and current supply lines formed on a glass substrate 12 in a grid pattern as shown in FIG. And a positive electrode 14 (for example, an ITO electrode), which can be driven by the TFT circuit 40 and is disposed in each grid, and is connected to the 4, a strip-shaped organic thin-film layer 24 for red light emission, an organic thin-film layer 26 for blue light emission, and an organic thin-film layer 28 for green-red light emission arranged in parallel with each other in order. A negative electrode 22 is disposed on the organic thin film layer 24 for blue light emission, the organic thin film layer 26 for blue light emission, and the organic thin film layer 28 for green light emission so as to cover them all. The organic thin film layer 24 for emitting red light, the organic thin film layer 26 for emitting blue light, and the organic thin film layer 28 for emitting green light have a hole transport layer 16, a light emitting layer 18, and an electron transport layer 20, respectively. .

In the active matrix panel, for example, as shown in FIG. 5, scanning lines 46 provided in a plurality of parallel lines and data lines 42 and a current supply line 44 provided in a plurality of parallel lines cross each other at right angles. In each grid, a switching TFT 48 and a driving TFT 50 are connected to form a circuit. When a current is applied from the driving circuit 38, the switching TFT 48 and the driving TFT 50 can be driven for each grid. In each of the grids, the organic thin-film elements 24, 26, and 28 for blue light emission, green light emission, and red light emission function as pixels, and the scanning lines arranged in the horizontal direction in the active matrix panel. When current is applied from one of the drive circuits 38 to one of the current supply lines 46 and the current supply line 44 arranged in the vertical direction, the switching TFT 48 located at the intersection is driven, and the driving TFT 48 is accordingly driven. The TFT 50 is driven, and the organic EL element 52 at that position emits light. By controlling the light emission of each pixel, a full-color image can be easily formed.

The organic EL display of the present invention includes, for example, a computer, a vehicle display, an outdoor display, a household device, a business device, a household appliance, a traffic display, a clock display, a calendar display, and a luminaire. It can be suitably used in various fields such as netting screens and audio equipment. Hereinafter, examples of the present invention will be described, but the present invention is not limited to these examples.

(Example 1)

Synthesis of [Cu I (quin) ₂ ] ₂

[Cu I (quin) ₂ ] ₂ was synthesized using Cu I and quinoline as raw materials according to the method described in J. Chem. Soc. . That is, as shown in the following reaction formula, 5 ml of a saturated aqueous solution of potassium iodide was added to a suspension obtained by adding 0.76 g of Cu I to 5 Om 1 of acetone while stirring. When 1.03 g of quinoline was added thereto, a bright yellow precipitate was formed. This mixture The mixture was refluxed for 24 hours, and allowed to cool at room temperature for about 3 days, whereby yellow crystals (the organometallic dinuclear complex) were precipitated, and the desired [Cul (quin) ₂ ] ₂ was synthesized.

Cul in acetone

Kl in Η ₂₀ reflux 24h, cool to rt

quinoline

(Example 2)

Synthesis of [Cu I (quin)] ₄

[Cu I (quin)] ₄ was synthesized from Cu I and quinoline as raw materials according to the method described in J. Chem. Soc. Dalton Trans. 1986, 2303-230. That is, as shown in the following reaction formula, 15 ml of a saturated aqueous solution of potassium iodide was added to a suspension obtained by adding 1.52 g of Cu1 to 100 ml of acetone while stirring. Thereto, 0.52 g of quinoline was added. The mixture was refluxed for 24 hours, and the temperature of the solution was kept at 55 ° C. to precipitate the organometallic dinuclear complex, thereby synthesizing the desired [Cul (qin)] ₄ .

Cul in acetone

Kl in H ₂ 0 reflux 24h, 55 ° c

quinoline

(Example 3)

Fabrication of one organic EL device

Using the organometallic dinuclear complex synthesized in Example 1 as a light-emitting material, a polymer-dispersed organic EL device was produced as follows. In other words, forming an ITO electrode as the positive electrode The glass substrate thus obtained was subjected to ultrasonic cleaning with water, acetone and isopropyl alcohol, and subjected to UV ozone treatment. Then, on the ITO electrode, polyvinyl carbazole (PVC z) was applied to the organometallic dinuclear complex of Example 1 ([ A hole transport layer / light-emitting layer doped with 5% by mass of Cu I (qu in) ₂ ] ₂ ) was coated to a thickness of 50 nm by spin coating. Next, the hole transport layer and luminescent layer, vacuum deposition device (degree of vacuum ^{= 1 X 10- 6 To rr (} 1. 3 X 1 0- 4 P a), the substrate temperature == room temperature) using a Then, an aluminum quinoline complex (Alq) as an electron transport layer was deposited so as to have a thickness of 2 Onm. An A 1 -Li alloy (Li content = 0.5% by mass) as a negative electrode was deposited on the electron transport layer so as to have a thickness of 50 nm. Thus, an organic EL device was manufactured.

(Example 4)

(1) Preparation of organic EL device (1)

The polymer-dispersed organic EL device of Example 4 was produced in the same manner as in Example 1 except that the organometallic dinuclear complex (Cu l (qu in)) ₄ ) synthesized in Example 2 was used as a light emitting material. did.

When a voltage was applied to the ITO electrode (positive electrode) and the A1-Li alloy (negative electrode) in the fabricated organic EL elements of Examples 3 and 4, the organic EL elements emitted red light at a voltage of 5 V or more. Was observed.

The emission luminance (cd / m ² ) at an applied voltage of 10 V and the effective half life of the organic EL element were measured by constant current measurement with the initial luminance set to 100 cd Zm ² . Table 1 shows the results.

INDUSTRIAL APPLICABILITY According to the present invention, the conventional problems can be solved, and And a suitable organic metal dinuclear complex, an organic EL device using the organic metal dinuclear complex, having excellent thermal and electrical stability, and having excellent lifetime and luminous efficiency, and using the organic EL device A high-performance, long-life organic EL display can be provided.

Claims

The scope of the claims

1. An organic thin film layer is provided between a positive electrode and a negative electrode, and the organic thin film layer has at least two group I metal elements coordinated by a ligand having at least one π-conjugated moiety. An organic EL device comprising an organometallic dinuclear complex crosslinked by a halogen atom.

2. The organic EL device according to claim 1, wherein the organometallic dinuclear complex is represented by the following structural formula (1). Π

Structural formula (1) ιιιιιιι

Here, in the structural formula (1), M represents a Group 1B metal element. L represents a ligand coordinated to satisfy the stable coordination number of the metal element M and having at least one π-conjugated moiety. X represents a halogen atom. η represents an integer of 1 to 2. m represents an integer of 1 or more.

3. The organic EL device according to any one of claims 1 to 2, wherein the organometallic dinuclear complex is represented by the following structural formula (2). Π

X M

Structural formula (2)

M X

Ln In the structural formula (2), M represents a Group 1B metal element. L is the metal element M Represents a ligand coordinated so as to satisfy the stable coordination number and having at least one π-conjugated moiety. Represents a halogen atom. η represents an integer of 1 to 2.

4. The ligand comprises, as a part of an aromatic ring, an atom capable of monodentate or bidentate coordination bond with a Group 1 metal element, and the atom includes a nitrogen atom, an oxygen atom, a sulfur atom, The organic EL device according to any one of claims 1 to 3, wherein the organic EL device is selected from a selenium atom, a tellurium atom, a polonium atom, and a phosphorus atom.

5. The organic EL device according to any one of claims 1 to 4, wherein the ligand is represented by any of the following structural formulas.

Pyridine quinoline 2, 2'-biviridine In the above formulas, R ¹ represents a halogen atom, an alkoxy group, an amino group, an alkyl group, a cycloalkyl group, an aryl group or an aryloxy group. It may be further substituted. ρ represents an integer from 0 to 5

6.1 The organic EL device according to any one of claims 1 to 5, wherein the group B metal element is selected from Cu, Ag, and Au.

7. The organic EL device according to claim 1, wherein the number of group B metal elements is any one of two and four.

8. The organic EL device according to any one of claims 1 to 7, wherein the organometallic dinuclear complex is represented by any of the following structural formulas.

9. The organic thin film layer has a hole transport layer and a light emitting layer, and the hole transport layer and light emitting layer has an organic thin film layer between a positive electrode and a negative electrode. Contains an organometallic dinuclear complex in which at least two of the Group 1 metal elements coordinated by a ligand having at least one π-conjugated moiety are cross-linked by a halogen atom. 9. The organic EL device according to any one of items 1 to 8.

10. The organic thin film layer has a light emitting layer sandwiched between a hole transport layer and an electron transport layer, and the light emitting layer contains an organometallic dinuclear complex as a light emitting material. Item 9. The organic EL device according to any one of items 8.

11. The organic EL device according to claim 10, wherein the light-emitting layer contains a low-molecular host material having an organometallic dinuclear complex as a guest compound.

12. Low-molecular host material, 4, 4, One-bis (2, 2 ⁵ one Jifuwe two Rubiniru) one 1, 1, One Bifue - Le (DP VB i), p-Seshikifueniru (p-SP), 1 , 3,6,8-tetraphenylpyrene (tppy), N, N, dinaphthyl-N, N, diphenyl-1- [1,1,1-biphenyl] -14,4, diamine (NPD), oxine complex and 12. The organic EL device according to claim 11, which is selected from sorbazole derivatives.

13. The organic EL device according to any one of claims 10 to 12, wherein the light-emitting layer contains a carbazole derivative represented by the following structural formula (5).

Structural formula (5)

Here, in the structural formula (5), Ar represents a divalent or trivalent group containing an aromatic ring, or a divalent or trivalent group containing a heterocyclic aromatic ring. R ⁴ and R ⁵ are each independently a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, an aryl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, a carboxyl group, an alkoxy group An alkylsulfonyl group, a hydroxyl group, an amide group, an aryloxy group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group, which may be further substituted with a substituent.

14. A claim according to claim 13, wherein the sorbazole derivative is selected from 4,4,1-bis (9-potassium lupazolyl) -biphenyl (CBP) represented by the following structural formula (13) and derivatives thereof. Organic EL device. Structural formula (13)

15. The organic EL device according to any one of claims 10 to 14, wherein the light-emitting layer contains a high-molecular host material having an organometallic dinuclear complex as a guest compound.

16. Polymer host materials include polyparaphenylenevinylene (PPV), polythiophene (PAT), polyparaphenylene (PPP), polyvinylcarbazonole (PVCz), polyfluorene (PF), and polyacetylene (PA). 16. The organic EL device according to claim 15, wherein the organic EL device is selected from these derivatives.

17. The polymer-based host material is a polybutylcarbazole (PVCz) derivative represented by the following structural formula (14), and the content of the organometallic dinuclear complex in the light-emitting layer is determined by the polybulcarbazole (PVC). z) The organic EL device according to any one of claims 15 to 16, wherein the amount is 0.01 to 50% by mass relative to the derivative.

Structural formula (14)

However, in the structural formula (14), R ¹¹ and R ¹² each represent a plurality of substituents provided at any position of the cyclic structure, and each independently represents a hydrogen atom, a halogen atom, an alkoxy group, an amino group Including alkyl, cycloalkyl, nitrogen and sulfur atoms Represents an aryl group or an aryloxy group, which may be further substituted with a substituent. R ¹¹ and R ¹² may be bonded to each other at any adjacent substitution position to form an aromatic ring which may contain a nitrogen atom, a sulfur atom, or an oxygen atom; May be further substituted with a group. X represents an integer.

18. The electron transport material contained in the electron transport layer is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) represented by the following structural formula (15). Item 18. The organic EL device according to any one of Items 10 to 17.

Structural formula (15)

19. The organic EL device according to any one of claims 1 to 18, which is for red coloring.

20. An organic metal which is used in an organic EL device, wherein at least two of the Group 1 metal elements coordinated by a ligand having at least one _π- conjugated moiety are crosslinked by a halogen atom. Binuclear complex.

21. The organometallic dinuclear complex according to claim 20, represented by the following structural formula (1). Π

Structural formula (1)

III ΙΙ Μ ιιιιιιπιι out III X

Ln In the structural formula (1), M represents a Group 1B metal element. L is the metal element M Represents a ligand coordinated to M so as to satisfy the stable coordination number of and having at least one π-conjugated moiety. X represents a halogen atom. η represents an integer of 1 to 2. m represents an integer of 1 or more.

22. The organometallic dinuclear complex according to claim 21, wherein the organometallic dinuclear complex is represented by the following structural formula (2). Π

X river in M

Marauder NOTE Structural formula (2)

M X

However, in the structural formula (1), M represents a Group 1B metal element. L represents a ligand coordinated to the metal element M so as to satisfy the stable coordination number of the metal element M and having at least one π-conjugated moiety. X represents a halogen atom. η represents an integer of 1 to 2.

23. The ligand comprises, as a part of the aromatic ring, an atom capable of coordinating monodentate or bidentate bond to the Group 1 metal element, and the atom is a nitrogen atom, an oxygen atom, or a sulfur atom. 23. The organometallic dinuclear complex according to any one of claims 20 to 22 selected from selenium, tellurium, polonium and phosphorus atoms.

24. The organometallic dinuclear complex according to claim 23, wherein the ligand is represented by any of the following structural formulas.

Pyridine quinoline 2, 2'-bibiridine wherein R ¹ represents a halogen atom, an alkoxy group, an amino group, an alkyl group, a cycloalkyl group, an aryl group or an aryloxy group. It may be substituted. P represents an integer of 0 to 5.

25. The organometallic dinuclear complex according to any one of claims 20 to 24, wherein the Group 1B metal element is selected from Cu, Ag and Au.

26. The organometallic dinuclear complex according to any one of claims 20 to 25, wherein the number of group 1 B metal elements is any of 2 to 4.

27. The organometallic dinuclear complex according to any one of claims 20 to 26, which is used as a light emitting material in an organic EL device.

28. An organic EL display using the organic EL device according to any one of claims 1 to 19.

29. The organic EL display according to claim 28, which is one of a passive matrix panel and an active matrix panel.