JP5182133B2 - Composition for organic electroluminescent device and organic electroluminescent device - Google Patents

Description

  The present invention relates to a composition used for an organic electroluminescence device, and more specifically, a composition for an organic electroluminescence device excellent in film formability and wet process suitability, and further, high efficiency and long life using the composition. The present invention relates to an organic electroluminescent element, an organic EL display using the organic electroluminescent element, and organic EL illumination.

  In recent years, as a thin film type electroluminescent element, an organic electroluminescent element using an organic thin film has been developed instead of using an inorganic material. The organic electroluminescent device usually has a hole injection layer, a hole transport layer, an organic light emitting layer, an electron transport layer, etc. between the anode and the cathode, and suitable for each layer such as red, green, blue, etc. Development of light emitting devices is progressing.

  In addition, as a method for forming each layer of the organic electroluminescent element, there are a vapor deposition film forming method and a wet film forming method. The vapor deposition method has a problem in terms of yield when manufacturing a medium or large full color panel for a television or a monitor. Therefore, the wet film-forming method is suitable for these large area applications.

  However, when forming a constituent layer of an organic electroluminescence device by a wet film-forming method, in particular, in order to form a light-emitting layer by a wet film-forming method, a film-forming composition for forming a light-emitting layer formed by dissolving the material of the light-emitting layer An underlayer that is resistant to the object, that is, does not dissolve in the film-forming composition for forming the light emitting layer, is required. In order to make the underlayer insoluble in the solvent of the composition for forming the light emitting layer, it is preferable to use a solvent-insoluble polymer material cured by a crosslinking reaction. As a polymer excellent in solvent solubility, a polymer compound containing a specific repeating unit is found, and a crosslinked polymer compound obtained by crosslinking this polymer compound. The organic electroluminescent element which formed the positive hole transport layer was proposed (patent document 1).

  According to the cross-linked polymer compound described in Patent Document 1, it is easy to stack organic electroluminescent elements by a wet film formation method, and a good organic electroluminescent element is obtained, but further improvement in performance is desired. It is.

JP 2008-2213012 A

The present invention has been made in view of the above problems.
That is, the present invention is a composition useful for an organic layer formed by a wet film formation method of an organic electroluminescence device, and can provide an organic electroluminescence device having a high efficiency and a long life by the wet film formation method. It is an object to provide a composition for a light-emitting element.
The present invention also provides a high-efficiency, long-life organic electroluminescence device, and an organic EL display and organic EL illumination using the organic electroluminescence device, using the composition for organic electroluminescence device. Let it be an issue.

As a result of intensive studies by the present inventors, when an organic electroluminescence device is produced by a wet film-forming method using a polymer, an organic electric field obtained when a predetermined amount of a transition metal is present together with a polyarylamine derivative-based polymer. The inventors have found that the performance of the light-emitting element is remarkably improved, and that an organic electroluminescent element having a long lifetime, high luminance and high efficiency can be provided, and the present invention has been achieved.

That is, the composition for an organic electroluminescence device of the present invention (invention 1) is characterized by containing a polyarylamine derivative-based polymer and 200 to 1000 ppm of a transition metal with respect to the polymer.

The composition for an organic electroluminescent device according to claim 2 is characterized in that, in claim 1, the polyarylamine derivative-based polymer is a charge transporting polymer.

The composition for an organic electroluminescent device according to claim 3 is characterized in that, in claim 2, the polyarylamine derivative-based polymer is a hole transporting compound comprising a polymer containing a repeating unit having a crosslinkable group. To do.

A composition for an organic electroluminescent element according to a fourth aspect is characterized in that in any one of the first to third aspects, a solvent is further contained.
The composition for an organic electroluminescent element according to claim 5 is characterized in that in any one of claims 1 to 4, the transition metal is copper or palladium.

The organic electroluminescent element of the present invention (Claim 6 ) is an organic electroluminescent element having an anode, a cathode, and an organic layer provided between both electrodes, and the organic layer is any one of Claims 1 to 5 . It is a layer formed using the composition for organic electroluminescent elements of 1 item | term.

The organic electroluminescent device of the present invention (Claim 7), an anode, a cathode, and an organic electroluminescent device having an organic layer disposed between two electrodes, as the organic layer, and the polyamide re Ruamin derivative-based polymer It has a layer containing 200 to 1000 ppm of transition metal based on the polymer.

The organic electroluminescent element of claim 8 is characterized in that, in claim 6 or 7 , the organic layer further has a light emitting layer, and the light emitting layer is a layer formed by a wet film forming method.

The organic EL display of the present invention (invention 9 ) and the organic EL lighting of the present invention (invention 10 ) have the organic electroluminescence element.

  ADVANTAGE OF THE INVENTION According to this invention, the composition for organic electroluminescent elements useful for a wet film-forming method can be provided, and a highly efficient and long-life organic electroluminescent element is used using this composition for organic electroluminescent elements. Can be provided.

  Therefore, the organic electroluminescent device using the organic electroluminescent device composition for wet film formation of the present invention is a flat panel display (for example, for OA computer or wall-mounted television), an in-vehicle display device, a mobile phone display, and a surface emission. It can be applied to a light source (for example, a light source of a copying machine, a backlight light source of a liquid crystal display or an instrument), a display board, or a marker lamp utilizing its characteristics as a body, and its technical value is high.

It is a schematic diagram of the cross section which shows embodiment of the organic electroluminescent element of this invention.

  Embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention, and the present invention does not exceed the gist thereof. Not specific to the content.

[Composition for organic electroluminescence device]
The composition for organic electroluminescent elements of the present invention comprises a polymer and 100 to 2000 ppm of a transition metal based on the polymer. The polymer is preferably a charge transporting polymer, and the charge transporting polymer is more preferably a hole transporting polymer. Moreover, it is preferable that the composition for organic electroluminescent elements of this invention contains a solvent further.
Such a composition for an organic electroluminescence device of the present invention is suitable as a wet film-forming composition for forming a hole injection layer or a hole transport layer, particularly a hole transport layer, of an organic electroluminescence device described later. It is.

<Transition metal>
First, the effect of the transition metal contained in the composition for organic electroluminescent elements of the present invention will be described.
Conventionally, the charge transporting material used for the organic electroluminescence device is mainly formed by a vapor deposition method, and a material with high purity and few impurities has been considered ideal. On the other hand, as described above, practically, it is more advantageous to produce a light emitting device with a large screen by using a wet film formation method than a vapor deposition method, and therefore, a material suitable for the wet film formation method has been developed. Although it was started, it is known that a film formed by a vapor deposition method has a high film density, whereas a film formed by a wet film formation method in the presence of air or nitrogen has a low density. Thus, there is a problem that the performance of the light-emitting element is significantly deteriorated due to the state of such a low-density film, that is, gas molecules or the like are mixed between molecules constituting the film.

  Although the details of the mechanism of the effect of improving the device performance by using the composition for organic electroluminescence device of the present invention containing a predetermined amount of transition metal with respect to the polymer are not yet clear, the wet film formation method reduces the density. In other words, the interaction between molecules is very weak and the distance is long, and the transition metal improves the performance of the light emitting device by modifying the film formed by incorporating various gas molecules. It seems to be letting it. In other words, it is presumed that the presence of transition metals in the film in the form of atoms or complexes partially strengthens the interaction between the polymer chains and forms stable segments. It is presumed that this is a factor for enhancing the durability of the element against the above.

  In the present invention, the transition metal may be added to the organic electroluminescent element composition in any form. For example, a separately produced polymer may be dissolved in a solvent, and a transition metal or a transition metal-containing compound may be added and concentrated therein, or a transition metal or a transition metal-containing compound may be added at the time of polymer production to purify the produced polymer. Sometimes the transition metal content may be adjusted to a preferred amount.

  Examples of the transition metal or the transition metal-containing compound used include metals such as Cu, Fe, Co, Ni, Cr, V, Pd, Pt, and Ag, and compounds thereof. In terms of safety and cost, Copper and palladium and their compounds are preferred.

The copper compound is not particularly limited, and most copper compounds are used, but cuprous iodide, cuprous chloride, cuprous oxide, cuprous bromide, cuprous cyanide, cuprous sulfate , Cupric sulfate, cupric chloride, cupric hydroxide, cupric oxide, cupric bromide, cupric phosphate, cuprous nitrate, cupric nitrate, copper carbonate, first acetic acid Copper, cupric acetate and the like are preferable. Among these, CuCl, CuCl ₂ , CuBr, CuBr ₂ , CuI, CuO, Cu ₂ O, CuSO ₄ , and Cu (OCOCH ₃ ) ₂ are particularly preferable because they are easily available.

  As the palladium compound, halides, sulfates, nitrates, organic acid salts and the like can be used. The palladium compound is not particularly limited, and examples thereof include tetravalent palladium compounds such as sodium hexachloropalladium (IV) tetrahydrate and potassium hexachloropalladium (IV); palladium (II) chloride, bromide Palladium (II), palladium acetate (II), palladium acetylacetonate (II), dichlorobis (benzonitrile) palladium (II), dichlorobis (acetonitrile) palladium (II), dichlorobis (triphenylphosphine) palladium (II), dichloro Divalent palladium compounds such as tetraamminepalladium (II), dichloro (cycloocta-1,5-diene) palladium (II), palladium trifluoroacetate (II); tris (dibenzylideneacetone) dipalladium (0), tris (di Benzylideneace Emissions) dipalladium chloroform complex (0), it may be mentioned tetrakis (triphenylphosphine) palladium (0) 0-valent palladium compounds such as.

  These transition metals and transition metal-containing compounds may be used alone or in combination of two or more.

  The transition metal content in the composition for organic electroluminescent elements is 100 ppm or more, preferably 150 ppm or more, more preferably 200 ppm or more, and 2000 ppm or less, preferably 1500 ppm or less, with respect to the polymer in the composition for organic electroluminescence elements. More preferably, it is 1000 ppm or less. If the transition metal content is too small, the above-described effects due to the inclusion of the transition metal are not effectively expressed. If the transition metal content is too large, there is a possibility that problems such as the generation of foreign substances may occur during wet film formation.

  Here, the transition metal content is the content of the total transition metal with respect to the total polymer weight contained in the composition for organic electroluminescent elements, and when a transition metal-containing compound is used, the transition metal is included. Expressed in conversion amount.

  The transition metal content in the organic electroluminescent element composition or the organic layer (polymer layer) can be measured by ICP / MS measurement using a microwave wet decomposition method.

<Polymer>
As described above, the polymer contained in the composition for organic electroluminescent elements of the present invention is preferably a charge transporting polymer, and more preferably a hole transporting polymer.
In particular, the hole transporting polymer is preferably a polymer (polymer) exemplified as a hole transporting compound used in a hole injection layer or a hole transporting layer, which will be described later, and among them, a polymer containing a repeating unit having a crosslinkable group. A coalescence (crosslinkable polymer) is preferred.

  The polymer contained in the composition for organic electroluminescent elements of the present invention preferably has a weight average molecular weight of 10,000 or more, more preferably 15,000 or more, preferably 2000000 or less, and 1000000 or less. Is more preferable. The number average molecular weight is preferably 3000 or more, more preferably 6000 or more, preferably 1000000 or less, and more preferably 500000 or less.

  Only 1 type of these polymers may be contained in the composition for organic electroluminescent elements of this invention, and 2 or more types may be contained. When 2 or more types are contained, it adjusts so that a transition metal may be 100-2000 ppm with respect to the total amount.

<Solvent>
It is preferable that the composition for organic electroluminescent elements of the present invention contains a solvent.
The solvent contained in the composition for organic electroluminescent elements of the present invention is not particularly limited as long as it is a solvent that dissolves solutes such as polymers and transition metal-containing compounds contained in the composition for organic electroluminescent elements satisfactorily. For example, aromatic hydrocarbons such as toluene, xylene, methicylene, cyclohexylbenzene, tetralin; halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene, trichlorobenzene; 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, Aromatic ethers such as anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole; phenyl acetate, phenyl propionate, methyl benzoate, benzoate Ethyl acetate, propyl benzoate, benzoic acid n Aromatic esters such as butyl; ketones having alicyclic rings such as cyclohexanone and cyclooctanone; aliphatic ketones such as methyl ethyl ketone and dibutyl ketone; alcohols having alicyclic rings such as methyl ethyl ketone, cyclohexanol and cyclooctanol; butanol, hexanol and the like Aliphatic alcohols; aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate (PGMEA); aliphatics such as ethyl acetate, n-butyl acetate, ethyl lactate, and n-butyl lactate Esters can be used. Of these, aromatic hydrocarbons such as toluene, xylene, methicylene, cyclohexylbenzene, tetralin and the like are preferable in that they have low water solubility and are not easily altered.

  Since organic electroluminescent devices use many materials such as cathodes that deteriorate significantly due to moisture, the presence of moisture in the composition causes moisture to remain in the dried film, degrading the device characteristics. The possibility is considered and it is not preferable.

  Examples of the method for reducing the amount of water in the composition include dehydration of the solvent in advance by distillation or use of a desiccant, nitrogen gas sealing, use of a solvent with low water solubility, and the like. In particular, it is preferable to use a solvent having low water solubility because the solution film can prevent whitening by absorbing moisture in the atmosphere during the wet film forming process. From such a viewpoint, the composition for organic electroluminescent elements to which the present embodiment is applied includes, for example, a solvent having a water solubility at 25 ° C. of 1% by weight or less, preferably 0.1% by weight or less. It is preferable to contain 10% by weight or more in the composition.

  Further, in order to reduce a decrease in film formation stability due to evaporation of the solvent from the composition during wet film formation, the solvent of the composition for organic electroluminescent elements has a boiling point of 100 ° C. or higher, preferably a boiling point of 150. It is effective to use a solvent having a boiling point of 200 ° C. or higher, more preferably 200 ° C. or higher. In order to obtain a more uniform film, it is necessary for the solvent to evaporate from the liquid film immediately after the film formation at an appropriate rate. For this purpose, the boiling point is usually 80 ° C. or higher, preferably the boiling point is 100 ° C. or higher. It is effective to use a solvent having a boiling point of 120 ° C. or more, usually less than 270 ° C., preferably less than 250 ° C., more preferably less than 230 ° C.

  A solvent that satisfies the above-mentioned conditions, ie, solute solubility, evaporation rate, and water solubility conditions, may be used alone. However, if a solvent that satisfies all the conditions cannot be selected, two or more solvents may be mixed. It can also be used.

<Other ingredients>
In the composition for organic electroluminescent elements of the present invention, various other solvents may be contained as necessary in addition to the above-mentioned solvent, polymer and transition metal. Examples of such other solvents include amides such as N, N-dimethylformamide and N, N-dimethylacetamide, and dimethyl sulfoxide.
Moreover, various additives, such as a leveling agent and an antifoamer, may be included.

  In addition, when two or more layers are laminated by a wet film formation method, in order to prevent these layers from being compatible with each other, a photocurable resin or a thermosetting resin is used for the purpose of curing and insolubilizing after film formation. Can also be contained.

<Concentration of material in composition for organic electroluminescence device>
The solid content concentration of the polymer, transition metal, and components (leveling agents, etc.) that can be added as necessary in the composition for organic electroluminescent elements of the present invention is usually 0.01% by weight or more, preferably 0.8%. 05% by weight or more, more preferably 0.1% by weight or more, further preferably 0.5% by weight or more, most preferably 1% by weight or more, usually 80% by weight or less, preferably 50% by weight or less, more preferably Is 40% by weight or less, more preferably 30% by weight or less, and most preferably 20% by weight or less. When this concentration is below the lower limit, it is difficult to form a thick film when forming a thin film, and when it exceeds the upper limit, it is difficult to form a thin film.

<Method for Preparing Composition for Organic Electroluminescent Device>
The composition for organic electroluminescent elements of the present invention is prepared by dissolving solutes such as polymers and transition metals in a suitable solvent. In order to shorten the time required for the dissolution step and to keep the solute concentration in the composition uniform, the solute is usually dissolved while stirring the liquid. The dissolution step may be performed at room temperature, but when the dissolution rate is slow, it can be heated and dissolved. After completion of the dissolution step, a filtration step such as filtering may be performed as necessary.

[Organic electroluminescence device]
The organic electroluminescent element of the present invention is an organic electroluminescent element having an anode, a cathode, and an organic layer provided between both electrodes, and the organic electroluminescent element composition of the present invention is used as the organic layer. Or a layer containing 100 to 2000 ppm of transition metal with respect to the polymer (hereinafter referred to as “transition metal”) as an organic layer provided between the anode and the cathode. It may be referred to as a “containing layer”).

  Examples of the organic layer include a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and the like. A layer formed using the composition for organic electroluminescent elements of the present invention, The transition metal-containing layer may be used in any layer, but a layer on which a light emitting layer is formed, that is, a hole injection layer or a hole transport layer is preferable, and in particular, a hole transport layer. Is preferred. In this case, the light emitting layer is preferably formed by a wet film formation method.

  In the present invention, the wet film forming method includes, for example, spin coating method, dip coating method, die coating method, bar coating method, blade coating method, roll coating method, spray coating method, capillary coating method, ink jet method, screen printing. This method is a wet film formation method such as a method, a gravure printing method, or a flexographic printing method. Among these film forming methods, a spin coating method, a spray coating method, and an ink jet method are preferable because they are suitable for the liquid property specific to the composition for organic electroluminescence devices of the present invention used for organic electroluminescence devices.

  Below, the layer structure of the organic electroluminescent element of this invention, its general formation method, etc. are demonstrated with reference to FIG.

  FIG. 1 is a schematic cross-sectional view showing a structural example of an organic electroluminescent element 10 of the present invention. In FIG. 1, 1 is a substrate, 2 is an anode, 3 is a hole injection layer, 4 is a hole transport layer, 5 Represents a light-emitting layer, 6 represents a hole blocking layer, 7 represents an electron transport layer, 8 represents an electron injection layer, and 9 represents a cathode.

{substrate}
The substrate 1 serves as a support for the organic electroluminescent element, and a quartz or glass plate, a metal plate or a metal foil, a plastic film, a sheet, or the like is used. In particular, a glass plate or a transparent synthetic resin plate such as polyester, polymethacrylate, polycarbonate, polysulfone or the like is preferable. When using a synthetic resin substrate, it is necessary to pay attention to gas barrier properties. If the gas barrier property of the substrate is too small, the organic electroluminescent element may be deteriorated by the outside air that has passed through the substrate, which is not preferable. For this reason, a method of providing a gas barrier property by providing a dense silicon oxide film or the like on at least one surface of the synthetic resin substrate is also a preferable method.

{anode}
The anode 2 serves to inject holes into the layer on the light emitting layer side.

  This anode 2 is usually a metal such as aluminum, gold, silver, nickel, palladium, platinum, a metal oxide such as an oxide of indium and / or tin, a metal halide such as copper iodide, carbon black, or It is composed of a conductive polymer such as poly (3-methylthiophene), polypyrrole, or polyaniline.

  In general, the anode 2 is often formed by a sputtering method, a vacuum deposition method, or the like. In addition, when forming the anode 2 using fine metal particles such as silver, fine particles such as copper iodide, carbon black, conductive metal oxide fine particles, and conductive polymer fine powder, an appropriate binder resin solution It is also possible to form the anode 2 by dispersing it and applying it onto the substrate 1. Furthermore, in the case of a conductive polymer, a thin film can be directly formed on the substrate 1 by electrolytic polymerization, or the anode 2 can be formed by applying a conductive polymer on the substrate 1 (Appl. Phys. Lett. 60, 2711, 1992).

  The anode 2 usually has a single-layer structure, but it can also have a laminated structure made of a plurality of materials if desired.

  The thickness of the anode 2 varies depending on the required transparency. When transparency is required, the visible light transmittance is usually 60% or more, preferably 80% or more. In this case, the thickness of the anode 2 is usually 5 nm or more, preferably 10 nm or more, and is usually 1000 nm or less, preferably about 500 nm or less. When it may be opaque, the thickness of the anode 2 is arbitrary, and the anode 2 may be the same as the substrate 1. Furthermore, it is also possible to laminate different conductive materials on the anode 2 described above.

  For the purpose of removing impurities adhering to the anode 2 and adjusting the ionization potential to improve the hole injection property, the surface of the anode 2 is treated with ultraviolet (UV) / ozone, or with oxygen plasma or argon plasma. It is preferable to do.

{Hole injection layer}
The hole injection layer 3 is a layer that transports holes from the anode 2 to the light emitting layer 5, and is usually formed on the anode 2.

  The method for forming the hole injection layer 3 according to the present invention may be a vacuum deposition method or a wet film formation method, and is not particularly limited, but the hole injection layer 3 is formed by a wet film formation method from the viewpoint of reducing dark spots. It is preferable.

  The thickness of the hole injection layer 3 is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less.

<Formation of hole injection layer by wet film formation method>
When forming the hole injection layer 3 by wet film formation, the material for forming the hole injection layer 3 is usually mixed with an appropriate solvent (hole injection layer solvent) to form a film-forming composition (positive A composition for forming a hole injection layer), and applying the composition for forming a hole injection layer on a layer (usually an anode) corresponding to the lower layer of the hole injection layer 3 by an appropriate technique. The hole injection layer 3 is formed by coating and drying. The composition for forming a hole injection layer may be the composition for an organic electroluminescence device of the present invention containing a predetermined amount of a transition metal. In particular, when the organic electroluminescent device does not have a hole transport layer and the light emitting layer is directly formed on the hole injection layer, the composition for forming a hole injection layer is the composition for an organic electroluminescent device of the present invention. It is preferable that it is a thing.

(Hole transporting compound)
The composition for forming a hole injection layer usually contains a hole transporting compound and a solvent as constituent materials of the hole injection layer.

  The hole transporting compound is a compound having a hole transporting property that is usually used in a hole injection layer of an organic electroluminescence device, and may be a polymer compound or the like, a monomer or the like. Although it may be a low molecular weight compound, it is preferably a high molecular weight compound.

  The hole transporting compound is preferably a compound having an ionization potential of 4.5 eV to 6.0 eV from the viewpoint of a charge injection barrier from the anode 2 to the hole injection layer 3. Examples of hole transporting compounds include aromatic amine derivatives, phthalocyanine derivatives, porphyrin derivatives, oligothiophene derivatives, polythiophene derivatives, benzylphenyl derivatives, compounds in which tertiary amines are linked by a fluorene group, hydrazone derivatives, silazane derivatives, silanamines Derivatives, phosphamine derivatives, quinacridone derivatives, polyaniline derivatives, polypyrrole derivatives, polyphenylene vinylene derivatives, polythienylene vinylene derivatives, polyquinoline derivatives, polyquinoxaline derivatives, carbon and the like.

  In the present invention, a derivative includes, for example, an aromatic amine derivative and includes an aromatic amine itself and a compound having an aromatic amine as a main skeleton. It may be a mer.

  The hole transporting compound used as the material for the hole injection layer 3 may contain any one of these compounds alone, or may contain two or more. When two or more hole transporting compounds are contained, the combination thereof is arbitrary, but one or more aromatic tertiary amine polymer compounds and one or two other hole transporting compounds are used. It is preferable to use the above in combination.

  Among the above examples, an aromatic amine compound is preferable from the viewpoint of amorphousness and visible light transmittance, and an aromatic tertiary amine compound is particularly preferable. Here, the aromatic tertiary amine compound is a compound having an aromatic tertiary amine structure, and includes a compound having a group derived from an aromatic tertiary amine.

  The type of the aromatic tertiary amine compound is not particularly limited, but from the viewpoint of uniform light emission due to the surface smoothing effect, a polymer compound having a weight average molecular weight of 1,000 or more and 1,000,000 or less (a polymerizable compound in which repeating units are linked) is further included. preferable. Preferable examples of the aromatic tertiary amine polymer compound include a polymer compound having a repeating unit represented by the following formula (I).

（上記各式中、Ａｒ^６〜Ａｒ^１６は、それぞれ独立して、置換基を有していてもよい芳香族炭化水素基または置換基を有していてもよい芳香族複素環基を表す。Ｒ^１およびＲ^２は、それぞれ独立して、水素原子または任意の置換基を表す。）） (In Formula (I), Ar ¹ and Ar ² each independently represent an aromatic hydrocarbon group which may have a substituent or an aromatic heterocyclic group which may have a substituent. .Ar ³ to Ar ⁵ represent each independently, an aromatic optionally substituted hydrocarbon group or optionally substituted aromatic heterocyclic group .Y is the following Represents a linking group selected from the group of linking groups, and among Ar ^{1 to} Ar ⁵ , two groups bonded to the same N atom may be bonded to each other to form a ring.

(In said each formula, Ar < ⁶ > -Ar < ¹⁶ > represents each independently the aromatic hydrocarbon group which may have a substituent, or the aromatic heterocyclic group which may have a substituent. R ¹ and R ² each independently represents a hydrogen atom or an arbitrary substituent.))

As the aromatic hydrocarbon group and the aromatic heterocyclic group of Ar ^{1 to} Ar ¹⁶ , a benzene ring, a naphthalene ring, a phenanthrene ring, a thiophene from the viewpoint of the solubility, heat resistance, hole injection / transport property of the polymer compound A group derived from a ring or a pyridine ring is preferred, and a group derived from a benzene ring or a naphthalene ring is more preferred.

The aromatic hydrocarbon group and aromatic heterocyclic group of Ar ^{1 to} Ar ¹⁶ may further have a substituent. The molecular weight of the substituent is usually 400 or less, preferably about 250 or less. As the substituent, an alkyl group, an alkenyl group, an alkoxy group, an aromatic hydrocarbon group, an aromatic heterocyclic group and the like are preferable.

When R ¹ and R ² are optional substituents, examples of the substituent include an alkyl group, an alkenyl group, an alkoxy group, a silyl group, a siloxy group, an aromatic hydrocarbon group, and an aromatic heterocyclic group. .

  Specific examples of the aromatic tertiary amine polymer compound having a repeating unit represented by the formula (I) include those described in International Publication No. 2005/089024.

  In addition, as a hole transporting compound, a conductive polymer (PEDOT / PSS) obtained by polymerizing 3,4-ethylenedioxythiophene (3,4-ethylenedioxythiophene), a polythiophene derivative, in high molecular weight polystyrene sulfonic acid. Is also preferred. Moreover, the end of this polymer may be capped with methacrylate or the like.

  The concentration of the hole transporting compound in the composition for forming a hole injection layer is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.01% by weight or more, preferably in terms of film thickness uniformity. Is 0.1% by weight or more, more preferably 0.5% by weight or more, and usually 70% by weight or less, preferably 60% by weight or less, more preferably 50% by weight or less. If this concentration is too high, film thickness unevenness may occur, and if it is too low, defects may occur in the formed hole injection layer.

(Electron-accepting compound)
The composition for forming a hole injection layer preferably contains an electron accepting compound as a constituent material of the hole injection layer.

  The electron-accepting compound is preferably a compound having an oxidizing power and the ability to accept one electron from the above-described hole transporting compound, specifically, a compound having an electron affinity of 4 eV or more is preferable, and 5 eV or more. The compound which is the compound of these is further more preferable.

  Examples of such electron-accepting compounds include triarylboron compounds, metal halides, Lewis acids, organic acids, onium salts, salts of arylamines and metal halides, and salts of arylamines and Lewis acids. Examples thereof include one or more compounds selected from the group. More specifically, an onium salt substituted with an organic group such as 4-isopropyl-4′-methyldiphenyliodonium tetrakis (pentafluorophenyl) borate and triphenylsulfonium tetrafluoroborate (International Publication No. WO 2005/089024); High valent inorganic compounds such as iron (III) chloride (Japanese Patent Laid-Open No. 11-251067), ammonium peroxodisulfate; cyano compounds such as tetracyanoethylene, tris (pendafluorophenyl) borane (Japanese Patent Laid-Open No. 2003-31365) Aromatic boron compounds such as); fullerene derivatives; iodine; sulfonate ions such as polystyrene sulfonate ions, alkylbenzene sulfonate ions, camphor sulfonate ions, and the like.

  These electron accepting compounds can improve the conductivity of the hole injection layer by oxidizing the hole transporting compound.

  The content of the electron-accepting compound in the hole-injecting layer or the composition for forming a hole-injecting layer with respect to the hole-transporting compound is usually 0.1 mol% or more, preferably 1 mol% or more. However, it is usually 100 mol% or less, preferably 40 mol% or less.

(Other components)
As a material for the hole injection layer, other components may be further contained in addition to the above-described hole transporting compound and electron accepting compound as long as the effects of the present invention are not significantly impaired. Examples of other components include various light emitting materials, electron transporting compounds, binder resins, and coating property improving agents. In addition, only 1 type may be used for another component and it may use 2 or more types together by arbitrary combinations and a ratio.

(solvent)
At least one of the solvents of the composition for forming a hole injection layer used in the wet film formation method is preferably a compound that can dissolve the constituent material of the hole injection layer. The boiling point of this solvent is usually 110 ° C. or higher, preferably 140 ° C. or higher, particularly 200 ° C. or higher, usually 400 ° C. or lower, and preferably 300 ° C. or lower. If the boiling point of the solvent is too low, the drying speed is too high and the film quality may be deteriorated. Further, if the boiling point of the solvent is too high, it is necessary to increase the temperature of the drying step, which may adversely affect other layers and the substrate.

  Examples of the solvent include ether solvents, ester solvents, aromatic hydrocarbon solvents, amide solvents, and the like.

  Examples of ether solvents include aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and propylene glycol-1-monomethyl ether acetate (PGMEA); 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole , Phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, aromatic ethers such as 2,4-dimethylanisole, and the like.

  Examples of the ester solvent include aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate.

  Examples of the aromatic hydrocarbon solvent include toluene, xylene, cyclohexylbenzene, 3-isopropylpropylphenyl, 1,2,3,4-tetramethylbenzene, 1,4-diisopropylbenzene, cyclohexylbenzene, and methylnaphthalene. Can be mentioned.

  Examples of the amide solvent include N, N-dimethylformamide, N, N-dimethylacetamide, and the like.

  In addition, dimethyl sulfoxide and the like can also be used.

  These solvent may use only 1 type and may use 2 or more types by arbitrary combinations and a ratio.

(Film formation method)
After preparing the composition for forming the hole injection layer, the composition is applied on the layer corresponding to the lower layer of the hole injection layer 3 (usually the anode 2) by wet film formation, and dried. The hole injection layer 3 is formed.

  The temperature in the film forming step is preferably 10 ° C. or higher, and preferably 50 ° C. or lower, in order to prevent film loss due to the formation of crystals in the composition.

  Although the relative humidity in a film-forming process is not limited unless the effect of this invention is impaired remarkably, it is 0.01 ppm or more normally and 80% or less normally.

  After the film formation, the film of the composition for forming a hole injection layer is usually dried by heating. Examples of the heating means used in the heating step include a clean oven, a hot plate, infrared rays, a halogen heater, microwave irradiation and the like. Among them, a clean oven and a hot plate are preferable in order to uniformly apply heat to the entire film.

  The heating temperature in the heating step is preferably heated at a temperature equal to or higher than the boiling point of the solvent used in the composition for forming a hole injection layer as long as the effects of the present invention are not significantly impaired. In the case of a mixed solvent containing two or more types of solvents used in the hole injection layer, at least one type is preferably heated at a temperature equal to or higher than the boiling point of the solvent. In consideration of an increase in the boiling point of the solvent, the heating step is preferably performed at 120 ° C. or higher, preferably 410 ° C. or lower.

  In the heating step, the heating time is not limited as long as the heating temperature is not lower than the boiling point of the solvent of the composition for forming a hole injection layer and sufficient insolubilization of the coating film does not occur. Is less than a minute. If the heating time is too long, the components of the other layers tend to diffuse, and if it is too short, the hole injection layer tends to be inhomogeneous. Heating may be performed in two steps.

<Formation of hole injection layer by vacuum deposition>
When the hole injection layer 3 is formed by vacuum deposition, one or more of the constituent materials of the hole injection layer 3 (the aforementioned hole transporting compound, electron accepting compound, etc.) are placed in a vacuum container. Put in crucibles installed (in case of using two or more materials, put them in each crucible), evacuate the inside of the vacuum vessel to about 10 ⁻⁴ Pa with a suitable vacuum pump, and then heat the crucible (two types When using the above materials, heat each crucible) and evaporate by controlling the amount of evaporation (when using two or more materials, evaporate by independently controlling the amount of evaporation) and face the crucible Then, the hole injection layer 3 is formed on the anode 2 of the substrate placed on the substrate. In addition, when using 2 or more types of materials, the hole injection layer 3 can also be formed by putting those mixtures into a crucible, heating and evaporating.

The degree of vacuum at the time of vapor deposition is not limited as long as the effect of the present invention is not significantly impaired, but is usually 0.1 × 10 ⁻⁶ Torr (0.13 × 10 ⁻⁴ Pa) or more, usually 9.0 × 10 ⁻⁶ Torr. (12.0 × 10 ⁻⁴ Pa) or less. The deposition rate is not limited as long as the effect of the present invention is not significantly impaired, but is usually 0.1 Å / second or more and usually 5.0 Å / second or less. The film forming temperature at the time of vapor deposition is not limited as long as the effect of the present invention is not significantly impaired, but is preferably 10 ° C. or higher, preferably 50 ° C. or lower.

{Hole transport layer}
The hole transport layer 4 can be formed on the hole injection layer 3 when there is a hole injection layer and on the anode 2 when there is no hole injection layer 3. The organic electroluminescent device of the present invention may have a configuration in which the hole transport layer is omitted.

  The method for forming the hole transport layer 4 according to the present invention may be a vacuum deposition method or a wet film formation method, and is not particularly limited, but the hole transport layer 4 is formed by a wet film formation method from the viewpoint of reducing dark spots. It is preferable.

  The material for forming the hole transport layer 4 is preferably a material having high hole transportability and capable of efficiently transporting injected holes. Therefore, it is preferable that the ionization potential is small, the transparency to visible light is high, the hole mobility is large, the stability is high, and impurities that become traps are not easily generated during manufacturing or use. In many cases, it is preferable not to quench the light emitted from the light emitting layer 5 or to form an exciplex with the light emitting layer 5 to reduce the efficiency because it is in contact with the light emitting layer 5.

  Such a material for the hole transport layer 4 may be any material conventionally used as a constituent material for the hole transport layer. For example, the hole transport property used for the hole injection layer 3 described above. What was illustrated as a compound is mentioned. In addition, arylamine derivatives, fluorene derivatives, spiro derivatives, carbazole derivatives, pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives, phthalocyanine derivatives, porphyrin derivatives, silole derivatives, oligothiophene derivatives, condensed polycyclic aromatics Hole transportable compounds such as group derivatives and metal complexes.

In addition, for example, polyvinylcarbazole derivatives, polyarylamine derivatives, polyvinyltriphenylamine derivatives, polyfluorene derivatives, polyarylene derivatives, polyarylene ether sulfone derivatives containing tetraphenylbenzidine, polyarylene vinylene derivatives, polysiloxane derivatives, polythiophenes And hole transporting compounds such as derivatives and poly (p-phenylene vinylene) derivatives. These may be any of an alternating copolymer, a random polymer, a block polymer, or a graft copolymer. Further, it may be a polymer having a branched main chain and three or more terminal portions, or a so-called dendrimer.
Of these, polyarylamine derivatives and polyarylene derivatives are preferred.

The polyarylamine derivative is preferably a polymer containing a repeating unit represented by the following formula (II). In particular, a polymer composed of a repeating unit represented by the following formula (II) is preferable. In this case, Ar ^a or Ar ^b may be different in each repeating unit.

(In formula (II), Ar ^a and Ar ^b each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent.)

  Examples of the aromatic hydrocarbon group which may have a substituent include, for example, a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, perylene ring, tetracene ring, pyrene ring, benzpyrene ring, chrysene ring, triphenylene ring, and acenaphthene. Examples thereof include a group derived from a 6-membered monocyclic ring or a 2-5 condensed ring, such as a ring, a fluoranthene ring, and a fluorene ring, and a group in which two or more of these rings are linked by a direct bond.

  Examples of the aromatic heterocyclic group which may have a substituent include a furan ring, a benzofuran ring, a thiophene ring, a benzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, and a carbazole ring. , Pyrroloimidazole ring, pyrrolopyrazole ring, pyrrolopyrrole ring, thienopyrrole ring, thienothiophene ring, furopyrrole ring, furofuran ring, thienofuran ring, benzoisoxazole ring, benzoisothiazole ring, benzimidazole ring, pyridine ring, pyrazine ring, pyridazine Ring, pyrimidine ring, triazine ring, quinoline ring, isoquinoline ring, sinoline ring, quinoxaline ring, phenanthridine ring, benzimidazole ring, perimidine ring, quinazoline ring, quinazolinone ring, azulene ring, etc. Or a group and the rings of from 2-4 fused rings include groups formed by connecting a direct bond or two or more rings.

From the viewpoints of solubility and heat resistance, Ar ^a and Ar ^b are each independently selected from the group consisting of a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, triphenylene ring, pyrene ring, thiophene ring, pyridine ring, and fluorene ring. A group derived from a selected ring or a group formed by linking two or more benzene rings (for example, a biphenyl group or a terphenyl group) is preferable.
Among these, a group derived from a benzene ring (phenyl group), a group formed by connecting two benzene rings (biphenyl group), and a group derived from a fluorene ring (fluorenyl group) are preferable.

Examples of the substituent that the aromatic hydrocarbon group and aromatic heterocyclic group in Ar ^a and Ar ^b may have include an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, and a dialkyl. Examples thereof include an amino group, a diarylamino group, an acyl group, a halogen atom, a haloalkyl group, an alkylthio group, an arylthio group, a silyl group, a siloxy group, a cyano group, an aromatic hydrocarbon ring group, and an aromatic heterocyclic group.

As the polyarylene derivative, an arylene group such as an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent exemplified as Ar ^a or Ar ^b in the formula (II) is used as its repeating unit. The polymer which has is mentioned.
As the polyarylene derivative, a polymer having a repeating unit composed of the following formula (III-1) and / or the following formula (III-2) is preferable.

(In formula (III-1), R ^a , R ^b , R ^c and R ^d are each independently an alkyl group, an alkoxy group, a phenylalkyl group, a phenylalkoxy group, a phenyl group, a phenoxy group, an alkylphenyl group, Represents an alkoxyphenyl group, an alkylcarbonyl group, an alkoxycarbonyl group, or a carboxy group, and t and s each independently represent an integer of 0 to 3. When t or s is 2 or more, they are contained in one molecule. A plurality of R ^a or R ^b may be the same or different, and adjacent R ^a or R ^b may form a ring.)

(In formula (III-2), R ^e and R ^f are each independently synonymous with R ^a , R ^b , R ^c or R ^d in formula (III-1). Independently, it represents an integer of 0 to 3. When r or u is 2 or more, a plurality of R ^e and R ^f contained in one molecule may be the same or different, and adjacent R ^e or R ^f may form a ring, and X represents an atom or a group of atoms constituting a 5-membered ring or a 6-membered ring.)

  Specific examples of X include an oxygen atom, a boron atom which may have a substituent, a nitrogen atom which may have a substituent, a silicon atom which may have a substituent, and a substituent. A phosphorus atom which may be substituted, a sulfur atom which may have a substituent, a carbon atom which may have a substituent, or a group formed by bonding these.

As the polyarylene derivative, in addition to the repeating unit composed of the above following formula (III-1) and / or the upper above formula (III-2), a further recurring unit represented by the following formula (III-3) It is preferable to have.

(In formula (III-3), Ar ^{c to} Ar ^j each independently represents an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent. Independently represents 0 or 1.)

Specific examples of Ar ^{c to} Ar ^j are the same as Ar ^a and Ar ^b in the formula (II).

  Specific examples of the above formulas (III-1) to (III-3) and specific examples of polyarylene derivatives include those described in JP-A-2008-98619.

  In the case of forming the hole transport layer 4 by a wet film formation method, a composition for forming a hole transport layer is prepared in the same manner as the formation of the hole injection layer 3 and then heated and dried after the wet film formation. .

The composition for forming a hole transport layer contains a solvent in addition to the above hole transport compound. The solvent used is the same as that used for the composition for forming a hole injection layer. The film forming conditions, heat drying conditions, and the like are the same as in the case of forming the hole injection layer 3.
This composition for forming a hole transport layer is preferably the composition for an organic electroluminescence device of the present invention containing a predetermined amount of a transition metal.

  In the case where the hole transport layer is formed by the vacuum deposition method, the film forming conditions are the same as those in the case of forming the hole injection layer 3.

  The hole transport layer 4 may contain various light emitting materials, electron transport compounds, binder resins, coating property improving agents, and the like in addition to the hole transport compound.

  The hole transport layer 4 may also be a layer formed by crosslinking a crosslinkable compound. The crosslinkable compound is a compound having a crosslinkable group, and forms a network polymer compound by crosslinking.

  Examples of this crosslinkable group include groups derived from cyclic ethers such as oxetane and epoxy; groups derived from unsaturated double bonds such as vinyl, trifluorovinyl, styryl, acrylic, methacryloyl and cinnamoyl; benzo Examples include groups derived from cyclobutene.

  The crosslinkable compound may be any of a monomer, an oligomer, and a polymer. The crosslinkable compound may have only 1 type, and may have 2 or more types by arbitrary combinations and ratios.

  As the crosslinkable compound, a hole transporting compound having a crosslinkable group is preferably used. Examples of the hole transporting compound include those exemplified above, and those having a crosslinkable group bonded to the main chain or side chain with respect to these hole transporting compounds. In particular, the crosslinkable group is preferably bonded to the main chain via a linking group such as an alkylene group. In particular, the hole transporting compound is preferably a polymer containing a repeating unit having a crosslinkable group, and the above formula (II) and formulas (III-1) to (III-3) can be used as a crosslinkable group. Is preferably a polymer having a repeating unit bonded directly or via a linking group.

  Examples of hole transporting compounds used as crosslinkable compounds and hole transporting compounds constituting repeating units having a crosslinkable group include pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives. Nitrogen-containing aromatic compound derivatives such as carbazole derivatives, phthalocyanine derivatives, porphyrin derivatives; triphenylamine derivatives; silole derivatives; oligothiophene derivatives, condensed polycyclic aromatic derivatives, metal complexes, and the like. Among them, nitrogen-containing aromatic derivatives such as pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives, carbazole derivatives; triphenylamine derivatives, silole derivatives, condensed polycyclic aromatic derivatives, metal complexes, etc. Particularly preferred are triphenylamine derivatives.

  In order to form the hole transport layer 4 by crosslinking the crosslinkable compound, a composition for forming a hole transport layer in which the crosslinkable compound is dissolved or dispersed in a solvent is usually prepared and deposited by wet film formation. To crosslink.

The composition for forming a hole transport layer may contain an additive for promoting a crosslinking reaction in addition to the crosslinking compound. Examples of additives that accelerate the crosslinking reaction include polymerization initiators and polymerization accelerators such as alkylphenone compounds, acylphosphine oxide compounds, metallocene compounds, oxime ester compounds, azo compounds, onium salts; condensed polycyclic hydrocarbons, And photosensitizers such as porphyrin compounds and diaryl ketone compounds.
Further, it may contain a coating property improving agent such as a leveling agent and an antifoaming agent; an electron accepting compound; a binder resin;

  In the composition for forming a hole transport layer, the crosslinkable compound is usually 0.01% by weight or more, preferably 0.05% by weight or more, more preferably 0.1% by weight or more, usually 50% by weight or less, preferably 20%. It is contained in an amount of not more than wt%, more preferably not more than 10 wt%.

  After forming a composition for forming a hole transport layer containing a crosslinkable compound at such a concentration on the lower layer (usually the hole injection layer 3), the composition is crosslinked by heating and / or irradiation with electromagnetic energy such as light. Are crosslinked to form a network polymer compound.

Conditions such as temperature and humidity during film formation are the same as those during the wet film formation of the hole injection layer 3.
The heating method after film formation is not particularly limited. As heating temperature conditions, it is 120 degreeC or more normally, Preferably it is 400 degrees C or less.
The heating time is usually 1 minute or longer, preferably 24 hours or shorter. The heating means is not particularly limited, and means such as placing a laminated body having a deposited layer on a hot plate or heating in an oven is used. For example, conditions such as heating on a hot plate at 120 ° C. or more for 1 minute or more can be used.

  In the case of irradiation with electromagnetic energy such as light, a method of irradiating directly using an ultraviolet / visible / infrared light source such as an ultra-high pressure mercury lamp, a high-pressure mercury lamp, a halogen lamp or an infrared lamp, or the above-mentioned light source is incorporated. Examples include a mask aligner and a method of irradiation using a conveyor type light irradiation device. In electromagnetic energy irradiation other than light, for example, there is a method of irradiation using a device that irradiates a microwave generated by a magnetron, a so-called microwave oven. As the irradiation time, it is preferable to set conditions necessary for reducing the solubility of the film, but irradiation is usually performed for 0.1 seconds or longer, preferably 10 hours or shorter.

  Heating and irradiation of electromagnetic energy such as light may be performed individually or in combination. When combined, the order of implementation is not particularly limited.

  The film thickness of the hole transport layer 4 thus formed is usually 5 nm or more, preferably 10 nm or more, and usually 300 nm or less, preferably 100 nm or less.

{Light emitting layer}
When the hole injection layer 3 or the hole transport layer 4 is provided, the light emitting layer 5 is provided on the hole transport layer 4. The light emitting layer 5 is a layer that is excited by recombination of holes injected from the anode 2 and electrons injected from the cathode 9 between electrodes to which an electric field is applied, and becomes a main light emitting source.

<Light emitting layer material>
The light emitting layer 5 contains at least a material having a light emitting property (light emitting material) as a constituent material, and preferably a compound having a hole transporting property (hole transporting compound) or an electron transport. A compound (electron transporting compound) having the following properties: A light emitting material may be used as a dopant material, and a hole transporting compound, an electron transporting compound, or the like may be used as a host material.

<Light emitting material>
As the luminescent material, any known material can be applied, and a fluorescent luminescent material or a phosphorescent luminescent material can be used alone or in combination. A phosphorescent luminescent material is preferable from the viewpoint of internal quantum efficiency.

  For the purpose of improving the solubility in a solvent, it is also important to reduce the symmetry and rigidity of the light emitting material molecule or to introduce a lipophilic substituent such as an alkyl group.

  Examples of the fluorescent material that gives blue light emission include perylene, pyrene, anthracene, coumarin, p-bis (2-phenylethenyl) benzene, and derivatives thereof. Examples of green fluorescent materials include quinacridone derivatives and coumarin derivatives. Examples of yellow fluorescent light-emitting materials include rubrene and perimidone derivatives. Examples of red fluorescent materials include DCM compounds, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, azabenzothioxanthene and the like.

  Examples of the phosphorescent material include organometallic complexes containing a metal selected from Groups 7 to 11 of the periodic table.

Preferred examples of the metal in the phosphorescent organometallic complex containing a metal selected from Groups 7 to 11 of the periodic table include ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold. Preferred examples of these organometallic complexes include compounds represented by the following general formula (V) or the following general formula (VI).
ML _(q−j) L ′ _j (V)
(In general formula (V), M represents a metal, q represents the valence of the metal, L and L ′ represent a bidentate ligand, and j represents 0, 1 or 2.)

（一般式（VI）中、Ｍ^ｄは金属を表し、Ｔは炭素または窒素を表す。Ｒ^９２〜Ｒ^９５は、それぞれ独立に置換基を表す。ただし、Ｔが窒素の場合は、Ｒ^９４およびＲ^９５は無い。）

(In the general formula (VI), M ^d represents a metal, T represents carbon or nitrogen. R ^{92 to} R ⁹⁵ each independently represents a substituent. However, when T is nitrogen, R ⁹⁴ and R ⁹⁵ is not.)

Hereinafter, the compound represented by the general formula (V) will be described first.
In the general formula (V), M represents an arbitrary metal, and specific examples of preferable ones include the metals described above as the metal selected from Groups 7 to 11 of the periodic table.

  Moreover, the bidentate ligands L and L ′ in the general formula (V) each represent a ligand having the following partial structure.

  L ′ is particularly preferably the following from the viewpoint of the stability of the complex.

  In the partial structures of L and L ′, the ring A1 represents an aromatic hydrocarbon group or an aromatic heterocyclic group, and these may have a substituent. Ring A2 represents a nitrogen-containing aromatic heterocyclic group, and these may have a substituent.

  When the rings A1 and A2 have a substituent, preferred substituents include halogen atoms such as fluorine atoms; alkyl groups such as methyl groups and ethyl groups; alkenyl groups such as vinyl groups; methoxycarbonyl groups and ethoxycarbonyl groups. Alkoxycarbonyl groups; alkoxy groups such as methoxy groups and ethoxy groups; aryloxy groups such as phenoxy groups and benzyloxy groups; dialkylamino groups such as dimethylamino groups and diethylamino groups; diarylamino groups such as diphenylamino groups; carbazolyl groups; An acyl group such as an acetyl group; a haloalkyl group such as a trifluoromethyl group; a cyano group; an aromatic hydrocarbon group such as a phenyl group, a naphthyl group, and a phenanthyl group.

  More preferable examples of the compound represented by the general formula (V) include compounds represented by the following general formulas (Va), (Vb), and (Vc).

(In the general formula (Va), Ma represents the same metal as M, w represents the valence of the metal, and ring A1 represents an aromatic hydrocarbon group which may have a substituent, Ring A2 represents a nitrogen-containing aromatic heterocyclic group which may have a substituent.

(In general formula (Vb), Mb represents the same metal as M, and w represents the valence of the metal. Ring A1 may have an aromatic hydrocarbon group or substituent which may have a substituent. And ring A2 represents a nitrogen-containing aromatic heterocyclic group which may have a substituent.

(In the general formula (Vc), Mc represents the same metal as M, w represents the valence of the metal, j represents 0, 1 or 2. Furthermore, ring A1 and ring A1 ′ are Each independently represents an optionally substituted aromatic hydrocarbon group or an optionally substituted aromatic heterocyclic group, and ring A2 and ring A2 ′ are each independently (It represents a nitrogen-containing aromatic heterocyclic group which may have a substituent.)

  In the above general formulas (Va), (Vb), and (Vc), the group of ring A1 and ring A1 ′ is preferably, for example, phenyl group, biphenyl group, naphthyl group, anthryl group, thienyl group, furyl group, benzo Examples include thienyl group, benzofuryl group, pyridyl group, quinolyl group, isoquinolyl group, carbazolyl group and the like.

  In addition, the group of ring A2 and ring A2 ′ is preferably a pyridyl group, pyrimidyl group, pyrazyl group, triazyl group, benzothiazole group, benzoxazole group, benzimidazole group, quinolyl group, isoquinolyl group, quinoxalyl group, A phenanthridyl group and the like can be mentioned.

  Furthermore, the substituents that the compounds represented by the general formulas (Va), (Vb), and (Vc) may have include a halogen atom such as a fluorine atom; an alkyl group such as a methyl group and an ethyl group; vinyl Alkenyl groups such as methoxy groups; alkoxycarbonyl groups such as methoxycarbonyl groups and ethoxycarbonyl groups; alkoxy groups such as methoxy groups and ethoxy groups; aryloxy groups such as phenoxy groups and benzyloxy groups; dialkyls such as dimethylamino groups and diethylamino groups An amino group; a diarylamino group such as a diphenylamino group; a carbazolyl group; an acyl group such as an acetyl group; a haloalkyl group such as a trifluoromethyl group; a cyano group;

  When the said substituent is an alkyl group, the carbon number is 1 or more and 6 or less normally. Furthermore, when the substituent is an alkenyl group, the carbon number is usually 2 or more and 6 or less. When the substituent is an alkoxycarbonyl group, the carbon number is usually 2 or more and 6 or less. Further, when the substituent is an alkoxy group, the carbon number is usually 1 or more and 6 or less. Moreover, when a substituent is an aryloxy group, the carbon number is 6 or more and 14 or less normally. Furthermore, when the substituent is a dialkylamino group, the carbon number is usually 2 or more and 24 or less. Further, when the substituent is a diarylamino group, the carbon number is usually 12 or more and 28 or less. Furthermore, when the substituent is an acyl group, the carbon number is usually 1 or more and 14 or less. Moreover, when a substituent is a haloalkyl group, the carbon number is 1 or more and 12 or less normally.

  These substituents may be connected to each other to form a ring. As a specific example, a substituent of the ring A1 and a substituent of the ring A2 are bonded, or a substituent of the ring A1 ′ and a substituent of the ring A2 ′ are bonded. Two fused rings may be formed. Examples of such a condensed ring group include a 7,8-benzoquinoline group.

  Among them, as a substituent of ring A1, ring A1 ′, ring A2 and ring A2 ′, more preferably an alkyl group, an alkoxy group, an aromatic hydrocarbon group, a cyano group, a halogen atom, a haloalkyl group, a diarylamino group, a carbazolyl group Is mentioned.

  Further, Ma, Mb, and Mc in the general formulas (Va), (Vb), and (Vc) are preferably ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, or gold.

  Specific examples of the organometallic complex represented by the general formula (V), (Va), (Vb) or (Vc) are shown below, but are not limited to the following compounds (in the following, Ph is phenyl Represents a group).

  Among the organometallic complexes represented by the general formulas (V), (Va), (Vb), and (Vc), in particular, as the ligand L and / or L ′, a 2-arylpyridine-based ligand, , 2-arylpyridine, a compound having an arbitrary substituent bonded thereto, and a compound having an arbitrary group condensed thereto are preferable.

Next, the compound represented by the general formula (VI) will be described.
In the general formula (VI), M ^d represents a metal, and specific examples thereof include the metals described above as the metal selected from Groups 7 to 11 of the periodic table. Among these, ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum or gold is preferable, and divalent metals such as platinum and palladium are particularly preferable.

In the general formula (VI), R ⁹² and R ⁹³ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, or a carboxyl group. Represents an alkoxy group, an alkylamino group, an aralkylamino group, a haloalkyl group, a hydroxyl group, an aryloxy group, an aromatic hydrocarbon group or an aromatic heterocyclic group.

Further, when T is carbon, R ⁹⁴ and R ⁹⁵ each independently represent a substituent represented by the same examples as R ⁹² and R ⁹³ . Further, as described above, when T is nitrogen, there is no R ⁹⁴ or R ⁹⁵ .

R ^{92 to} R ⁹⁵ may further have a substituent. In this case, the substituent which may further be present is not particularly limited, and any group can be used as the substituent.
Furthermore, R ^{92 to} R ⁹⁵ may be connected to each other to form a ring, and this ring may further have an arbitrary substituent.

  Specific examples (T-1, T-10 to T-15) of the organometallic complex represented by the general formula (VI) are shown below, but are not limited to the following exemplified compounds. In the following, Me represents a methyl group, and Et represents an ethyl group.

  Moreover, as an organometallic complex, the compounds described in WO2005 / 019373 can also be used.

  Furthermore, the light emitting layer 5 may contain other components as long as the effects of the present invention are not significantly impaired. In addition, when forming the light emitting layer 5 with a wet film-forming method, it is preferable to use a low molecular weight material (molecular weight is usually 10,000 or less, preferably 5000 or less).

<Formation of light emitting layer>
As for the organic electroluminescent element of this invention, it is preferable that the light emitting layer is formed by the wet film-forming method.
In the case of forming the light emitting layer 5 by a wet film forming method, the light emitting layer forming composition is prepared by dissolving the material used for the light emitting layer in an appropriate solvent, and the film is formed using the composition.

  The solvent for the light-emitting layer contained in the composition for forming a light-emitting layer for forming the light-emitting layer 5 by the wet film-forming method according to the present invention is described as the solvent contained in the composition for forming a hole injection layer described above. It is the same as what I did.

  The solid content concentration of the light emitting material, charge transporting compound, etc. in the composition for forming a light emitting layer is usually 0.01% by weight or more and usually 70% by weight or less. If this concentration is too large, film thickness unevenness may occur, and if it is too small, defects may occur in the film.

  After wet-deposition of the composition for forming a light emitting layer, the resulting coating film is dried and the solvent is removed to form a light emitting layer. Specifically, it is the same as the method described in the formation of the hole injection layer. The method of the wet film forming method is not limited as long as the effect of the present invention is not significantly impaired, and any of the methods described above can be used.

  The thickness of the light emitting layer 5 is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 3 nm or more, preferably 5 nm or more, and usually 200 nm or less, preferably 100 nm or less. If the thickness of the light emitting layer 5 is too thin, defects may occur in the film, and if it is too thick, the driving voltage may increase.

{Hole blocking layer}
A hole blocking layer 6 may be provided between the light emitting layer 5 and an electron injection layer 8 described later. The hole blocking layer 6 is a layer laminated on the light emitting layer 5 so as to be in contact with the interface of the light emitting layer 5 on the cathode 9 side.

  The hole blocking layer 6 has a role of blocking holes moving from the anode 2 from reaching the cathode 9 and a role of efficiently transporting electrons injected from the cathode 9 toward the light emitting layer 5. Have

  The physical properties required for the material constituting the hole blocking layer 6 include high electron mobility, low hole mobility, a large energy gap (difference between HOMO and LUMO), and excited triplet level (T1). Is high. Examples of the material for the hole blocking layer satisfying such conditions include bis (2-methyl-8-quinolinolato) (phenolato) aluminum, bis (2-methyl-8-quinolinolato) (triphenylsilanolato) aluminum, and the like. Mixed metal complexes such as bis (2-methyl-8-quinolato) aluminum-μ-oxo-bis- (2-methyl-8-quinolinato) aluminum binuclear metal complexes, distyrylbiphenyl derivatives, etc. Triazole derivatives such as styryl compounds (JP-A-11-242996), 3- (4-biphenylyl) -4-phenyl-5 (4-tert-butylphenyl) -1,2,4-triazole (JP-A-7 -41759), phenanthroline derivatives such as bathocuproine (JP-A-10-79297), and the like. That. Further, a compound having at least one pyridine ring substituted at positions 2, 4, and 6 described in International Publication No. 2005-022962 is also preferable as a material for the hole blocking layer 6.

  In addition, the material of the hole-blocking layer 6 may use only 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

  There is no restriction | limiting in the formation method of the hole-blocking layer 6. FIG. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

  The thickness of the hole blocking layer 6 is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 0.3 nm or more, preferably 0.5 nm or more, and usually 100 nm or less, preferably 50 nm or less.

  A hole relaxation layer may be provided in place of the hole blocking layer.

{Electron transport layer}
An electron transport layer 7 may be provided between the light emitting layer 5 and an electron injection layer 8 described later.

  The electron transport layer 7 is provided for the purpose of further improving the light emission efficiency of the device, and efficiently transports electrons injected from the cathode 9 between the electrodes to which an electric field is applied in the direction of the light emitting layer 5. Formed from a compound capable of

  As an electron transport compound used for the electron transport layer 7, usually, the electron injection efficiency from the cathode 9 or the electron injection layer 8 is high, and the injected electrons are transported efficiently with high electron mobility. The compound which can be used is used. Examples of the compound satisfying such conditions include metal complexes such as aluminum complexes of 8-hydroxyquinoline (Japanese Patent Laid-Open No. 59-194393), metal complexes of 10-hydroxybenzo [h] quinoline, oxadiazole derivatives , Distyrylbiphenyl derivatives, silole derivatives, 3-hydroxyflavone metal complexes, 5-hydroxyflavone metal complexes, benzoxazole metal complexes, benzothiazole metal complexes, trisbenzimidazolylbenzene (US Pat. No. 5,645,948), quinoxaline compounds ( JP-A-6-207169), phenanthroline derivative (JP-A-5-331459), 2-t-butyl-9,10-N, N'-dicyanoanthraquinonediimine, n-type hydrogenated amorphous silicon carbide , N-type zinc sulfide, n-type zinc Such as emissions of zinc, and the like.

  In addition, the material of the electron carrying layer 7 may use only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  There is no restriction | limiting in the formation method of the electron carrying layer 7. FIG. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

  The thickness of the electron transport layer 7 is arbitrary as long as the effect of the present invention is not significantly impaired, but is usually 1 nm or more, preferably 5 nm or more, and usually 300 nm or less, preferably 100 nm or less.

{Electron injection layer}
The electron injection layer 8 plays a role of efficiently injecting electrons injected from the cathode 9 into the light emitting layer 5. In order to perform electron injection efficiently, the material for forming the electron injection layer 8 is preferably a metal having a low work function. Examples include alkali metals such as sodium and cesium, and alkaline earth metals such as barium and calcium. Examples include lithium fluoride (LiF), magnesium fluoride (MgF ₂ ), lithium oxide (Li ₂ O), cesium carbonate (II) (CsCO ₃ ), and the like (Applied Physics Letters, 1997, Vol. 70, pp. 152; Japanese Patent Laid-Open No. 10-74586; see I Organic EL Display and Organic EL Lighting Transactions on Electron Devices, 1997, Vol. 44, pp. 1245; SID 04 Digest, pp. 154, etc.). The film thickness is usually preferably from 0.1 nm to 5 nm.

  Furthermore, an organic electron transport compound represented by a metal complex such as a nitrogen-containing heterocyclic compound such as bathophenanthroline or an aluminum complex of 8-hydroxyquinoline is doped with an alkali metal such as sodium, potassium, cesium, lithium, or rubidium ( (As described in JP-A-10-270171, JP-A-2002-1000047, JP-A-2002-1000048, etc.), it is possible to improve the electron injection / transport properties and achieve excellent film quality. preferable. In this case, the film thickness is usually 5 nm or more, preferably 10 nm or more, and is usually 200 nm or less, preferably 100 nm or less.

  In addition, the material of the electron injection layer 8 may use only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  There is no restriction | limiting in the formation method of the electron injection layer 8. FIG. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

{cathode}
The cathode 9 plays a role of injecting electrons into a layer (such as the electron injection layer 8 or the light emitting layer 5) on the light emitting layer 5 side.

  As the material of the cathode 9, the material used for the anode 2 can be used. However, in order to perform electron injection efficiently, a metal having a low work function is preferable. For example, tin, magnesium, indium, A suitable metal such as calcium, aluminum, silver, or an alloy thereof is used. Specific examples include low work function alloy electrodes such as magnesium-silver alloy, magnesium-indium alloy, and aluminum-lithium alloy.

  In addition, the material of the cathode 9 may use only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  The film thickness of the cathode 9 is usually the same as that of the anode 2.

  Further, for the purpose of protecting the cathode 9 made of a low work function metal, it is preferable to further stack a metal layer having a high work function and stable to the atmosphere because the stability of the device is increased. For this purpose, for example, metals such as aluminum, silver, copper, nickel, chromium, gold and platinum are used. In addition, these materials may be used only by 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

{Other layers}
The organic electroluminescent element of the present invention may have another configuration without departing from the gist thereof. For example, as long as the performance is not impaired, an arbitrary layer may be provided between the anode 2 and the cathode 9 in addition to the layers described above, and an arbitrary layer may be omitted. .

Examples of the layer that may be included include an electron blocking layer.
The electron blocking layer is provided between the hole injection layer 3 or the hole transport layer 4 and the light emitting layer 5 and prevents electrons moving from the light emitting layer 5 from reaching the hole injection layer 3. Thus, the probability of recombination of holes and electrons in the light emitting layer 5 is increased, the excitons generated are confined in the light emitting layer 5, and the holes injected from the hole injection layer 3 are efficiently collected. There is a role to transport in the direction of. In particular, when a phosphorescent material or a blue light emitting material is used as the light emitting material, it is effective to provide an electron blocking layer.

  The characteristics required for the electron blocking layer include high hole transportability, a large energy gap (difference between HOMO and LUMO), and a high excited triplet level (T1). Furthermore, in the present invention, when the light emitting layer 5 is formed as an organic layer according to the present invention by a wet film formation method, the electron blocking layer is also required to be compatible with the wet film formation. Examples of the material used for such an electron blocking layer include a copolymer of dioctylfluorene and triphenylamine typified by F8-TFB (International Publication No. 2004/084260).

  In addition, the material of an electron blocking layer may use only 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  There is no restriction | limiting in the formation method of an electron blocking layer. Therefore, it can be formed by a wet film forming method, a vapor deposition method, or other methods.

  Moreover, in the layer structure demonstrated above, it is also possible to laminate | stack components other than a board | substrate in reverse order. For example, in the case of the layer configuration of FIG. 1, the other components on the substrate 1 are the cathode 9, the electron injection layer 8, the electron transport layer 7, the hole blocking layer 6, the light emitting layer 5, the hole transport layer 4, the positive layer. The hole injection layer 3 and the anode 2 may be provided in this order.

  Furthermore, it is also possible to constitute the organic electroluminescent element according to the present invention by laminating components other than the substrate between two substrates, at least one of which is transparent.

In addition, a structure in which a plurality of components (light emitting units) other than the substrate are stacked in a plurality of layers (a structure in which a plurality of light emitting units are stacked) may be employed. In that case, instead of the interface layer between the steps (between the light emitting units) (in the case where the anode is ITO and the cathode is Al, these two layers), for example, a charge made of vanadium pentoxide (V ₂ O ₅ ) or the like. When a generation layer (Carrier Generation Layer: CGL) is provided, a barrier between steps is reduced, which is more preferable from the viewpoint of light emission efficiency and driving voltage.

  Furthermore, the organic electroluminescent device according to the present invention may be configured as a single organic electroluminescent device, or may be applied to a configuration in which a plurality of organic electroluminescent devices are arranged in an array. You may apply to the structure by which the cathode is arrange | positioned at XY matrix form.

  Each layer described above may contain components other than those described as materials unless the effects of the present invention are significantly impaired.

[Organic EL display and organic EL lighting]
The organic electroluminescent element of the present invention is used for organic EL displays and organic EL lighting. The organic electroluminescent device obtained by the present invention is described in, for example, “Organic EL Display” (Ohm, August 20, 2004, written by Shizushi Tokito, Chiba Adachi, and Hideyuki Murata). An organic EL display and organic EL illumination can be formed by the method.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to description of a following example, unless the summary is exceeded.

[Synthesis Example 1: Synthesis of Polymer According to Example (Crosslinkable Polymer H3-A)]

  In a reaction vessel, 9,9-dihexylfluorene-2,7-diboronic acid (3.0 g, 7.1 mmol), 4-bromoiodobenzene (4.42 g, 15.6 mmol), toluene (45 ml), and ethanol ( 45 ml), and nitrogen substitution was repeated under reduced pressure to create a nitrogen atmosphere in the system. Further, the system was sufficiently purged with nitrogen, tetrakis (triphenylphosphine) palladium (0.54 g, 0.5 mmol) was added, and degassed sodium carbonate (4.52 g, 43 mmol) in aqueous solution (22 ml) Was added and allowed to react for 6 hours. After completion of the reaction, water was added to the reaction solution and extracted with toluene. The obtained organic layer was washed twice with water, added with sodium sulfate, dehydrated and dried, and concentrated. The crude product was washed with n-hexane, purified by silica gel column chromatography (hexane / methylene chloride), and further washed with methylene chloride / methanol to obtain the desired product 1 (3.15 g).

  Aniline (0.951 g, 10.2 mmol), Compound a (0.125 g, 0.642 mmol), the target product 1 (3.50 g, 5.43 mmol), tert-butoxy sodium (3.34 g, 34.8 mmol) And toluene (25 ml) were charged, the inside of the system was sufficiently purged with nitrogen, and the mixture was heated to 50 ° C. (solution A). Tri-t-butylphosphine (0.18 g, 0.87 mmol) was added to a 5 ml toluene solution of tris (dibenzylideneacetone) dipalladium chloroform complex (0.11 g, 0.11 mmol) and heated to 50 ° C. ( Solution B). In a nitrogen stream, solution B was added to solution A and heated to reflux for 1.5 hours. After confirming disappearance of the raw material, the target product 1 (3.22 g, 5.00 mmol) was further added. After heating under reflux for 2 hours and confirming that the polymerization had started, the target product 1 (0.07 g, 0.11 mmol) was further added. The mixture was further heated under reflux for 2 hours, the reaction solution was allowed to cool, and the reaction solution was dropped into ethanol (250 ml) to crystallize the crude polymer.

  The obtained crude polymer was dissolved in 200 ml of toluene, bromobenzene (0.34 g, 2.1 mmol) and tert-butoxy sodium (3.34 g, 34.8 mmol) were charged, and the system was sufficiently purged with nitrogen. And heated to 50 ° C. (solution C). Tri-t-butylphosphine (0.09 g, 0.48 mmol) was added to a 5 ml toluene solution of tris (dibenzylideneacetone) dipalladium chloroform complex (0.06 g, 0.06 mmol) and heated to 50 ° C. ( Solution D). In a nitrogen stream, solution D was added to solution C, and heated to reflux for 2.5 hours. To this reaction solution, a toluene (2 ml) solution of N, N-diphenylamine (1.84 g, 10.9 mmol) and a solution D prepared again were added, and the mixture was further heated and refluxed for 6 hours. The reaction solution was allowed to cool and toluene was distilled off, followed by dropwise addition to ethanol (300 ml) to obtain a crude polymer.

  This crude polymer was dissolved in toluene, reprecipitated in acetone, and the precipitated polymer was separated by filtration. The obtained polymer was dissolved in toluene, washed with dilute hydrochloric acid, and reprecipitated with ammonia-containing ethanol. The polymer collected by filtration was purified three times by column chromatography to obtain the crosslinkable polymer H3-A, which was the target product 2, (3.59 g). This polymer had a weight average molecular weight (Mw) of 67850, a number average molecular weight (Mn) of 35400, and a degree of dispersion (Mw / Mn) = 1.92.

  When this crosslinkable polymer H3-A was subjected to ICP / MS measurement (manufactured by Agilent Technologies, ICP mass spectrometer HP4500 type) using a microwave wet decomposition method, the content of Pd as a transition metal was 400 ppm. .

[Synthesis Example 2: Synthesis of Polymer According to Comparative Example (Crosslinkable Polymer H3-B)]
The crosslinkable polymer H3-A synthesized in Synthesis Example 1 was dissolved in 300 ml of toluene, and washed 5 times with demineralized water. When the crosslinkable polymer H3-B that had been washed was subjected to ICP / MS measurement using a microwave wet decomposition method in the same manner as in Synthesis Example 1, the content of Pd as a transition metal was 45 ppm.

[Example 1: Production of organic electroluminescent device]
The organic electroluminescent element shown in FIG. 1 was produced.

  An indium tin oxide (ITO) transparent conductive film deposited on a glass substrate 1 with a thickness of 120 nm (manufactured by Sanyo Vacuum Co., Ltd., sputtered film product) using ordinary photolithography technology and hydrochloric acid etching Then, the anode 2 was formed by patterning into stripes having a width of 2 mm. The patterned ITO substrate is cleaned in the order of ultrasonic cleaning with an aqueous surfactant solution, water cleaning with ultrapure water, ultrasonic cleaning with ultrapure water, and water cleaning with ultrapure water, followed by drying with compressed air, and finally UV irradiation. Ozone cleaning was performed.

  First, a hole transporting polymer compound having a repeating structure represented by the following structural formula (P1) (weight average molecular weight: 26500, number average molecular weight: 12000), 4-isopropyl-4′- represented by the structural formula (A1) A composition for forming a hole injection layer containing methyldiphenyliodonium tetrakis (pentafluorophenyl) borate and ethyl benzoate as a solvent was prepared. This composition was formed into a film on the anode 2 by spin coating under the following conditions to obtain a hole injection layer 3 having a thickness of 30 nm.

<Composition for hole injection layer>
Solvent Ethyl benzoate Composition concentration (P1): 2.0% by weight
(A1): 0.8% by weight

<Film formation conditions for hole injection layer>
Spinner speed 1500rpm
Spinner rotation time 30 seconds Spin coat atmosphere In air Heating conditions In air, 230 ° C, 3 hours

  Subsequently, a composition for forming a hole transport layer containing a crosslinkable polymer (H3-A) having a Pd content of 400 ppm synthesized in Synthesis Example 1 represented by the following structural formula as a hole transporting polymer, and toluene as a solvent. The product (composition for organic electroluminescence device) was prepared, formed into a film by spin coating under the following conditions, and then crosslinked by heating to form a crosslinked film having a thickness of 20 nm (corresponding to the hole transport layer 4). .

<Composition for forming hole transport layer>
Solvent Toluene Solid concentration 0.4% by weight

<Hole transport layer deposition conditions>
Spinner speed 1500rpm
Spinner rotation time 30 seconds Spin coating atmosphere In nitrogen Heating conditions In nitrogen, 230 ° C, 1 hour

  Next, in forming the light emitting layer 5, the organic compound (C6) shown below as a host material, the following compound (D3) as a dopant material, and toluene as a solvent, the following light emitting layer forming composition Was prepared and spin-coated on the hole transport layer 4 under the following conditions to obtain a light-emitting layer 5 having a thickness of 40 nm.

<Composition for light emitting layer formation>
Solvent Toluene Composition concentration C6: 0.80% by weight
D3: 0.08% by weight

<Deposition conditions for light emitting layer>
Spinner speed 1500rpm
Spinner rotation time 30 seconds Spin coat atmosphere In nitrogen Heating condition Under reduced pressure (0.1 MPa), 130 ° C., 1 hour

Here, after the substrate on which the hole injection layer 3, the hole transport layer 4 and the light emitting layer 5 are formed is transferred into a vacuum vapor deposition apparatus and the apparatus is roughly evacuated by an oil rotary pump, the degree of vacuum in the apparatus is increased. After evacuating using a cryopump until the pressure became 5.1 × 10 ⁻⁴ Pa or less, a compound represented by the following structural formula (C-4) was stacked by a vacuum deposition method to obtain a hole blocking layer 6. At this time, the vapor deposition rate was controlled in the range of 0.7 to 1.0 kg / second, and the hole blocking layer 6 having a film thickness of 5 nm was formed by being laminated on the light emitting layer 5. The degree of vacuum during deposition was 1.9 to 2.0 × 10 ⁻⁴ Pa.

Subsequently, tris (8-hydroxyquinolinate) aluminum was heated and evaporated to form an electron transport layer 7. The degree of vacuum during vapor deposition is 1.3 × 10 ⁻⁴ Pa, the vapor deposition rate is controlled in the range of 0.6 to 1.0 kg / sec, and a 30 nm thick film is laminated on the hole blocking layer 6. An electron transport layer 7 was formed.

Here, the element that has been deposited up to the electron transport layer 7 is once taken out from the vacuum deposition apparatus into the atmosphere, and a 2 mm wide striped shadow mask is used as a cathode deposition mask. The device was placed in close contact with each other so as to be orthogonal to each other, placed in another vacuum vapor deposition apparatus, and evacuated until the degree of vacuum in the apparatus was 2.1 × 10 ⁻⁴ Pa or less in the same manner as the organic layer.

First, lithium fluoride (LiF) was controlled as the electron injection layer 8 at a deposition rate of 0.07 to 0.17 liters / second and a degree of vacuum of 2.3 to 2.4 × 10 ⁻⁴ Pa using a molybdenum boat. A film having a thickness of 0.5 nm was formed on the electron transport layer 7. Next, aluminum is similarly heated by a molybdenum boat as the cathode 9 and controlled at a deposition rate of 0.7 to 6.1 liters / second and a degree of vacuum of 2.3 to 2.7 × 10 ⁻⁴ Pa to a film thickness of 80 nm. An aluminum layer was formed. The substrate temperature during the above two-layer deposition was kept at room temperature.

Subsequently, in order to prevent the element from being deteriorated by moisture in the atmosphere during storage, a sealing process was performed by the method described below.
In a nitrogen glove box connected to a vacuum vapor deposition device, a photocurable resin (30Y-437 manufactured by ThreeBond Co., Ltd.) with a width of about 1 mm is applied to the outer peripheral portion of a 23 mm × 23 mm size glass plate, and the central portion is applied. A moisture getter sheet (manufactured by Dynic Co., Ltd.) was installed. On this, the board | substrate which complete | finished cathode formation was bonded together so that the vapor-deposited surface might oppose a desiccant sheet. Then, only the area | region where the photocurable resin was apply | coated was irradiated with ultraviolet light, and resin was hardened.

As described above, an organic electroluminescent element having a light emitting area portion having a size of 2 mm × 2 mm was obtained. The light emission characteristics of this element are as follows.
Luminance / current: 4.7 [cd / A] @ 100 cd / m ²
Voltage: 4.9 [V] @ 100 cd / m ²
Luminous efficiency: 2.9 [lm / W] @ 100 cd / m ²

  The maximum wavelength of the emission spectrum of the device was 465 nm, and it was identified as that from the compound (D3). The chromaticity was CIE (x, y) = (0.14, 0.17).

When the initial luminance of the obtained organic electroluminescent element was set to 1000 cd / m ² , the normalized 70% driving life in which the luminance decay time up to 80% of the initial luminance was normalized with the value of Comparative Example 1 described later. Is shown in Table 1. As shown in Table 1, by using the composition for organic electroluminescent elements of the present invention, an element having a long lifetime was obtained.

[Comparative Example 1]
In forming the hole transport layer 4 , the same as Example 1 except that the crosslinkable polymer (H3-B) of Comparative Example having a Pd content of 45 ppm obtained in Synthesis Example 2 was used as the hole transport polymer. Thus, an organic electroluminescent element was produced, and the driving life was measured in the same manner.

  As a result, the drive life was significantly shorter than that of Example 1 as shown in Table 1.

DESCRIPTION OF SYMBOLS 1 Substrate 2 Anode 3 Hole injection layer 4 Hole transport layer 5 Light emitting layer 6 Hole blocking layer 7 Electron transport layer 8 Electron injection layer 9 Cathode 10 Organic electroluminescent device

Claims (10)

  A composition for an organic electroluminescent device, comprising a polyarylamine derivative-based polymer and 200 to 1000 ppm of a transition metal based on the polymer.   The composition for organic electroluminescent elements according to claim 1, wherein the polyarylamine derivative polymer is a charge transporting polymer. Polya Li Ruamin derivative-based polymer, characterized in that it is a hole transporting compound comprising a polymer containing a repeating unit having a crosslinking group, the composition for organic electroluminescence element according to claim 2.   Furthermore, a solvent is contained, The composition for organic electroluminescent elements of any one of Claim 1 thru | or 3 characterized by the above-mentioned.   The composition for organic electroluminescent elements according to any one of claims 1 to 4, wherein the transition metal is copper or palladium.   An organic electroluminescence device having an anode, a cathode, and an organic layer provided between the two electrodes, wherein the organic layer uses the composition for an organic electroluminescence device according to any one of claims 1 to 5. An organic electroluminescent element, characterized in that the organic electroluminescent element is a layer formed. An anode, a cathode, and an organic electroluminescent device having an organic layer disposed between two electrodes, as organic layers, containing a transition metal of 200~1000ppm against Poria Li Ruamin derivative polymer and the polymer An organic electroluminescent device comprising a layer for forming an organic electroluminescent device.   The organic electroluminescent element according to claim 6 or 7, further comprising a light emitting layer as the organic layer, wherein the light emitting layer is a layer formed by a wet film forming method.   An organic EL display comprising the organic electroluminescent element according to claim 6.   An organic EL illumination comprising the organic electroluminescent element according to claim 6.

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