JPWO2017221662A1 - Method for manufacturing organic electroluminescent element and organic electroluminescent element - Google Patents

Abstract

〔ＸはＯ、Ｓ又はＮＲ_９を表す。Ｒ_１〜Ｒ_９はそれぞれ水素原子、置換基又は一般式（２）で表される置換基を表し、少なくとも一つは一般式（２）で表される置換基を表す。〕
【化２】

〔Ｌは連結基を表す。Ｒは置換基を表す。Ｌ及びＲのうち少なくとも一つはアルキレン基又はアルキル基を表す。〕An object of the present invention is to provide a manufacturing method that can be applied to a flexible substrate and can manufacture an organic EL element having high luminous efficiency and long life at low cost. The method for manufacturing the organic EL element is a method for manufacturing the organic EL element 10 including the light emitting layer 15, the block layer 16, and the electron transport layer 17 between the anode 12 and the cathode 19. It is formed using a coating liquid containing a compound having the structure of (1) and a polar fluorinated solvent.
[Chemical 1]

[X represents O, S or NR ₉ . R _{1 to} R ₉ each represent a hydrogen atom, a substituent, or a substituent represented by the general formula (2), and at least one represents a substituent represented by the general formula (2). ]
[Chemical 2]

[L represents a linking group. R represents a substituent. At least one of L and R represents an alkylene group or an alkyl group. ]

Description

  The present invention relates to a method for manufacturing an organic electroluminescent element and an organic electroluminescent element. In particular, the present invention is applicable to a flexible substrate, and relates to a method for manufacturing an organic electroluminescent element and an organic electroluminescent element capable of manufacturing an organic electroluminescent element with high luminous efficiency and long life at low cost.

  Conventionally, as a light-emitting electronic display device, there is an organic electroluminescence (hereinafter referred to as “organic EL”) element. An organic EL device has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and injects electrons and holes into the light emitting layer to recombine excitons. It is an element that emits light by utilizing light emission (fluorescence / phosphorescence) when the exciton is deactivated. Light emission is possible at a voltage of several volts to several tens of volts, and since it is a self-luminous type, it has a wide viewing angle, high visibility, and since it is a thin-film type solid-state device, it saves space and is portable. It attracts attention from the viewpoint of sex. Furthermore, the organic EL element has a feature that it is a surface light source.

  As the attractiveness of organic EL elements as surface emission and high-efficiency light sources increases, it is necessary to satisfy all of high emission efficiency, high luminance, and long life because of their functions as commercial products. Furthermore, in order to maximize the attractiveness of thin, light, and curved light sources, flexible displays and flexible lighting with organic EL elements formed on a flexible substrate have already been provided. Technology and material technology are needed.

  In response to these requirements, high performance has been achieved by using a vapor deposition method and forming a multi-layer structure by laminating each functional material on a flexible substrate. There is a problem that the manufacturing cost becomes high due to the low manufacturing equipment and material utilization efficiency for realizing a high degree of vacuum.

As a method of reducing the manufacturing cost of the organic EL element, there is a method of laminating each functional material by a wet method (hereinafter also referred to as a coating method) (see, for example, Patent Document 1).
However, many of the functional materials that make up the light-emitting layers and electron transport layers of organic EL devices are mostly composed of chemically similar structural skeletons and are close to solubility in the coating lamination solvent. May end up. Therefore, when stacking is attempted due to a difference in solubility between the solvent and the solute (functional material), about 4 layers including a hole transport layer and a hole injection layer stacked on the side opposite to the electron transport layer of the light emitting layer are stacked. Was the limit.

For such a problem, a lamination method using a curing agent has been proposed. For example, an organic EL device having two light emitting layers made of a crosslinkable polymer is disclosed (for example, see Patent Document 2).
In addition, for example, an electron transport material having a functional group such as a fluoroalkyl group and a light-emitting material are coated to form a mixed layer, and the electron transport material is moved in the mixed layer to transport electrons. A technique has been proposed in which a material and a light-emitting material are separated to form a pseudo laminated structure to enable lamination of four or more layers (for example, see Patent Document 3).

However, the technique described in Patent Document 2 requires post-treatment at a high temperature for a long time after coating film formation, and further layers cannot be stacked on the layer without post-treatment. Further, there is a problem that not only energy and time are required for post-processing, but also the flexible substrate is distorted by the energy, yield decreases, and manufacturing cost cannot be reduced.
Further, in the technique described in Patent Document 3, since mixing due to contact between the light emitting material and the electron transport material is unavoidable even after the material separation in the mixed layer, between the light emitting material and the electron transport material. Ligand exchange and complex formation occur, quenching occurs, and device performance deteriorates. Moreover, since molecular design is required over a plurality of types of materials, there is also a problem that it is difficult to design the entire layer.

Japanese Patent No. 5561272 JP-A-2015-174932 Japanese Patent No. 5656765

  The present invention has been made in view of the above-mentioned problems and situations, and the solution is applicable to a flexible substrate, and it can produce an organic electroluminescence device with high luminous efficiency and long life at low cost. It is providing the manufacturing method of an organic electroluminescent element which can be performed, and an organic electroluminescent element.

As a result of investigating the cause of the above-mentioned problems in order to solve the above-mentioned problems according to the present invention, in a method for producing an organic EL device comprising a light-emitting layer, a block layer, and an electron transport layer between an anode and a cathode. The block layer is formed by using a coating solution containing a compound having a structure represented by the general formula (1) and a polar fluorinated solvent, so that it can be applied to a flexible substrate and has high luminous efficiency. It was also found that a long-life organic electroluminescence device can be produced at low cost.
That is, the subject concerning this invention is solved by the following means.

1. A method for producing an organic electroluminescent device comprising a light emitting layer, a block layer, and an electron transport layer between an anode and a cathode,
The said block layer is formed using the coating liquid containing the compound which has a structure represented by following General formula (1), and a polar fluorinated solvent, The manufacturing method of the organic electroluminescent element characterized by the above-mentioned.

[In General Formula (1), X represents O, S or NR ₉ . R ₉ represents a hydrogen atom, a deuterium atom, an alkyl group, an alkenyl group, an alkynyl group, an arylalkyl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, or a non-aromatic heterocyclic ring. Represents a group or a substituent represented by the following general formula (2). R _{1 to} R ₈ are each a hydrogen atom, deuterium atom, halogen atom, cyano group, alkyl group, alkenyl group, alkynyl group, alkoxy group, acyl group, amino group, silyl group, phosphine oxide group, aromatic carbonization This represents a hydrogen ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, a non-aromatic heterocyclic group or a substituent represented by the following general formula (2). At least one of R _{1 to} R ₉ represents a substituent represented by the following general formula (2). R _{1 to} R ₉ may be the same as or different from each other, and may further have a substituent. ]

[In general formula (2), L represents an alkylene group, an alkenylene group, an o-phenylene group, an m-phenylene group, a p-phenylene group, an amide group or a divalent aromatic heterocyclic group, respectively, and further substituted. It may have a group. n represents an integer of 1 to 8. When n represents an integer of 2 or more, L of 2 or more may be the same as or different from each other. R is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a fluorinated alkyl group having 1 to 20 carbon atoms, an aromatic hydrocarbon ring group, an aromatic heterocyclic group or a non-aromatic group. Represents a hydrocarbon ring group, and may further have a substituent. m represents an integer of 1 to 3. At least one of L and R represents an alkylene group or an alkyl group. When there are a plurality of substituents represented by the general formula (2), L and R may be the same or different from each other, but they are not connected to each other to form a ring. ]

  2. 2. The method for producing an organic electroluminescent element according to item 1, wherein the polar fluorinated solvent is a solvent selected from a fluorinated alcohol, a fluorinated ester, and a fluorinated ether.

  3. The method for producing an organic electroluminescent element according to item 1 or 2, wherein the polar fluorinated solvent contains a fluorinated alcohol having 3 to 5 carbon atoms.

  4). Any one of the substituents represented by the general formula (2), wherein at least one L is an alkylene group having 1 to 6 carbon atoms, The manufacturing method of the organic electroluminescent element of description.

  5. Any one of the substituents represented by the general formula (2), wherein at least one R is an alkyl group having 1 to 6 carbon atoms, The manufacturing method of the organic electroluminescent element of description.

  6). The method for producing an organic electroluminescent element according to any one of claims 1 to 5, wherein the electron transport layer is formed using a coating liquid containing an electron transport material.

  7). 7. The method for producing an organic electroluminescent element according to item 6, wherein the coating liquid containing the electron transport material contains a polar fluorinated solvent.

  8). Any one of Items 1 to 7, wherein the light emitting layer is composed of a compound whose solubility in a polar fluorinated solvent is lower than the compound having the structure represented by the general formula (1). The manufacturing method of the organic electroluminescent element of one term.

  9. The method for producing an organic electroluminescent element according to any one of items 1 to 8, wherein the light emitting layer is composed of a compound having a molecular weight of 3000 or less.

  10. Item 1 to Item 9, wherein the light emitting layer contains a compound having a dibenzofuran ring, a dibenzothiophene ring or a carbazole ring, and having no alkyl group, alkenyl group, alkynyl group or arylalkyl group. The manufacturing method of the organic electroluminescent element as described in any one of the above.

11. An organic electroluminescence device comprising a light emitting layer, a block layer, and an electron transport layer between an anode and a cathode,
The said block layer contains the compound and polar fluorinated solvent which have a structure represented by following General formula (1), The organic electroluminescent element characterized by the above-mentioned.

[In General Formula (1), X represents O, S or NR ₉ . R ₉ represents a hydrogen atom, a deuterium atom, an alkyl group, an alkenyl group, an alkynyl group, an arylalkyl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, or a non-aromatic heterocyclic ring. Represents a group or a substituent represented by the following general formula (2). R _{1 to} R ₈ are each a hydrogen atom, deuterium atom, halogen atom, cyano group, alkyl group, alkenyl group, alkynyl group, alkoxy group, acyl group, amino group, silyl group, phosphine oxide group, aromatic carbonization This represents a hydrogen ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, a non-aromatic heterocyclic group or a substituent represented by the following general formula (2). At least one of R _{1 to} R ₉ represents a substituent represented by the following general formula (2). R _{1 to} R ₉ may be the same as or different from each other, and may further have a substituent. ]

[In general formula (2), L represents an alkylene group, an alkenylene group, an o-phenylene group, an m-phenylene group, a p-phenylene group, an amide group or a divalent aromatic heterocyclic group, respectively, and further substituted. It may have a group. n represents an integer of 1 to 8. When n represents an integer of 2 or more, L of 2 or more may be the same as or different from each other. R is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a fluorinated alkyl group having 1 to 20 carbon atoms, an aromatic hydrocarbon ring group, an aromatic heterocyclic group or a non-aromatic group. Represents a hydrocarbon ring group, and may further have a substituent. m represents an integer of 1 to 3. At least one of L and R represents an alkylene group or an alkyl group. When there are a plurality of substituents represented by the general formula (2), L and R may be the same or different from each other, but they are not connected to each other to form a ring. ]

  12 Item 12. The organic electroluminescent element according to item 11, wherein the polar fluorinated solvent is contained in an amount of 1000 ppm by mass or less as a whole of each constituent layer.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method and organic electroluminescent element of an organic electroluminescent element which can be applied also to a flexible substrate and can manufacture an organic electroluminescent element of high luminous efficiency and long life at low cost are provided. can do.
The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.
The compound having the structure represented by the general formula (1) according to the present invention includes an alkylene group or an alkyl group and has a structure close to a general host material that can be contained in the light emitting layer. The compound having the structure represented by the general formula (1) includes an alkylene group or an alkyl group having a crystallographically large disorder, so that the solubility in a solid state is improved and the light emitting layer is not dissolved. The solubility in (polar fluorinated solvent) is improved. Furthermore, since the reactivity to the light emitting material is reduced due to the effect of steric hindrance, a layer having a blocking function with little influence on the light emitting layer can be formed.
On the other hand, the polar fluorinated solvent used in the production method of the present invention is characterized by low intermolecular force and low surface free energy due to the low polarizability of C—F bond. Thereby, it has excellent water and oil repellency and non-adhesiveness, and when the block layer is formed using the coating liquid containing the polar fluorinated solvent, it is difficult to dissolve the underlying constituent material. In addition, when the block layer is formed using a polar fluorinated solvent, it is possible to suppress deterioration in device performance due to aggregation of the block layer material when the coating film is dried, and penetration of the block layer material into the lower layer Can also be suppressed.
In general, until the coating film (wet film) formed by the coating method is dried, surface tension acts on the surface of the coating film so as to minimize the surface free energy. Provides a hydrophobic group having a low surface energy on the surface of the coating film, and stabilizes the polar group and an aromatic ring having a relatively small hydrophobicity in an oriented state in the coating film. When the block layer is formed using a coating liquid containing a compound having a structure represented by the general formula (1) as in the present invention, the surface free energy is increased as described above until the coating film is dried. In order to minimize it, a portion having a large number of polar groups and aromatic rings and a small amount of hydrophobic groups is oriented to the light emitting layer side, and a portion containing a large amount of hydrophobic groups is oriented to the coating film surface side. As a result, the electron transport layer can be wet-formed with a hydrophilic polar solvent on the block layer formed by drying the coating film.
Therefore, according to the present invention, since the block layer is formed by the compound having the structure represented by the general formula (1) and the polar fluorinated solvent, it is mainly composed of a material that is easily dissolved in a solvent such as a low molecular compound. On the light emitting layer, the block layer can be laminated without dissolving the light emitting layer, and the electron transport layer can be laminated by a coating method without dissolving the block layer.

Schematic sectional view showing an example of an organic EL device according to the present invention

The method for producing an organic EL device of the present invention is a method for producing an organic EL device comprising a light emitting layer, a block layer, and an electron transport layer between an anode and a cathode, wherein the block layer is represented by a general formula. It is formed using a coating solution containing a compound having a structure represented by (1) and a polar fluorinated solvent. This feature is a technical feature common to or corresponding to each claim.
In the present invention, the polar fluorinated solvent is preferably a solvent selected from fluorinated alcohols, fluorinated esters and fluorinated ethers. By using these solvents, it is possible to more reliably achieve both dissolution inhibition of the lower layer and dissolution and orientation control of the compound having the structure represented by the general formula (1). It can be suitably obtained.
In the present invention, the polar fluorinated solvent preferably contains a fluorinated alcohol having 3 to 5 carbon atoms. As a result, the coating film can be leveled before the coating film is dried and volatilization unevenness can be suppressed, while solvent molecules are quickly discharged out of the film, so crystallization of solute molecules and deterioration of performance due to the inclusion of solvent in the layer. Since it can reduce, the effect of this invention can be exhibited to the maximum.
Moreover, in this invention, it is preferable that at least 1 L is a C1-C6 alkylene group among the substituents represented by the said General formula (2). When L is an alkylene group having 1 or more carbon atoms, solubility in a polar fluorinated solvent is improved, and crystallization of a compound having a structure represented by the general formula (1) can be suppressed. On the other hand, when L is an alkylene group having 6 or less carbon atoms, the electron mobility is reduced due to the formation of a rough film due to the disorder of the compound having the structure represented by the general formula (1) more than necessary. Therefore, the effects of the present invention can be maximized.
Moreover, in this invention, it is preferable that at least 1 R is a C1-C6 alkyl group among the substituents represented by the said General formula (2). When R is an alkyl group having 1 or more carbon atoms, the solubility in a polar fluorinated solvent is improved, and not only crystallization of the compound having the structure represented by the general formula (1) can be suppressed, but also to the light emitting layer. Can be prevented. On the other hand, when R is an alkyl group having 6 or less carbon atoms, it is possible to suppress a decrease in electron mobility due to an increase in the intermolecular distance of the compound having the structure represented by the general formula (1) more than necessary. The effects of the present invention can be maximized.
Moreover, in this invention, it is preferable to form the said electron carrying layer using the coating liquid containing an electron carrying material. Thereby, even when the electron transport layer is formed into a wet film, dissolution of the lower layer can be suppressed, and mixing of the electron transport layer component into the light emitting layer can be reduced, so that the effects of the present invention can be exhibited to the maximum.
Moreover, in this invention, it is preferable that the coating liquid containing the said electron transport material contains a polar fluorination solvent. This makes it difficult to apply the coating solution to the block layer, not only can suppress the lower layer penetration of the electron transport material and the block layer material, but can obtain an appropriate mixing of the interface between the block layer and the electron transport layer, A decrease in electron transportability can be suppressed, and the effects of the present invention can be exhibited to the maximum.
Moreover, in this invention, from a viewpoint of expression of the effect of this invention, the said light emitting layer is comprised with the compound whose solubility with respect to a polar fluorination solvent is lower than the compound which has a structure represented by the said General formula (1). It is preferable.
In the present invention, the light emitting layer is preferably composed of a compound having a molecular weight of 3000 or less. Thus, even if the light emitting layer is composed of a low-molecular compound that is easily dissolved in a solvent, other functional layers can be stacked without dissolving the light emitting layer, so that an organic EL element with high luminous efficiency and long life can be obtained. It can be manufactured reliably.
Moreover, in this invention, it is preferable that the said light emitting layer contains the compound which has a dibenzofuran ring, a dibenzothiophene ring, or a carbazole ring and does not have an alkyl group, an alkenyl group, an alkynyl group, or an arylalkyl group. Since the compound contained in the light emitting layer has a skeleton similar to that of the general formula (1), the electron transport property can be increased, and since a film having a high density can be formed by having no alkyl group or the like, a block Intrusion of the layer material into the light emitting layer can be suppressed, and the effects of the present invention can be exhibited to the maximum.

The organic EL device of the present invention is an organic EL device comprising a light emitting layer, a block layer, and an electron transport layer between an anode and a cathode, and the block layer is represented by the following general formula (1). And a polar fluorinated solvent.
In the present invention, the polar fluorinated solvent is preferably contained in an amount of 1000 mass ppm or less as a whole of each constituent layer. Thereby, without impairing charge transfer between the organic EL element materials, the organic EL element material is not reoriented by energy such as heat generated at the time of driving, and does not become crystal grains. There is no decline.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, in this application, "-" is used in the meaning which includes the numerical value described before and behind that as a lower limit and an upper limit.

<< Configuration of organic EL element >>
The configuration of the organic EL element produced by the method for producing an organic EL element of the present invention will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view of an organic EL element 10 which is an example of an organic EL element manufactured by the manufacturing method of the present invention.

  The organic EL element 10 includes a substrate 11, an anode 12, a hole injection layer 13, a hole transport layer 14, a light emitting layer 15, a block layer 16, an electron transport layer 17, an electron injection layer 18, and a cathode 19 in this order. Yes.

The element configuration of the organic EL element is not limited to the configuration example shown in FIG. 1. For example, the following configurations can be given as typical element configurations.
(1) Light emitting layer / block layer / electron transport layer (2) Hole transport layer / light emitting layer / block layer / electron transport layer (3) Hole transport layer / light emitting layer / block layer / electron transport layer / electron injection layer (4) Hole injection layer / hole transport layer / light emitting layer / block layer / electron transport layer (5) Hole injection layer / hole transport layer / light emitting layer / block layer / electron transport layer / electron injection layer (6) ) Hole injection layer / hole transport layer / electron blocking layer / light emitting layer / block layer / electron transport layer / electron injection layer Among the above, the configurations of (5) and (6) are preferably used, but limited thereto. Is not to be done.

  The light emitting layer is composed of a single layer or a plurality of layers. If necessary, a hole blocking layer (hole blocking layer), an electron injection layer (cathode buffer layer) or the like may be provided between the light emitting layer and the cathode, and between the light emitting layer and the anode. An electron blocking layer (electron barrier layer), a hole injection layer (anode buffer layer), and the like are provided. Each of these layers can be formed by a known material and method.

<< Method for Manufacturing Organic EL Element >>
The method for producing an organic EL device of the present invention is a method for producing an organic EL device comprising a light emitting layer, a block layer, and an electron transport layer between an anode and a cathode, wherein the block layer is represented by the general formula ( It is formed using a coating liquid containing a compound having a structure represented by 1) and a polar fluorinated solvent.

Taking the case of manufacturing the organic EL element 10 shown in FIG. 1 as an example, the manufacturing method of the organic EL element of the present invention will be specifically described.
First, the anode 12 is formed on the base material 11. Next, the hole injection layer 13 and the hole transport layer 14 are formed in this order on the anode 12. Next, the light emitting layer 15 is formed. Next, the block layer 16 is formed on the light emitting layer 15 using a block layer forming coating solution containing a compound having a structure represented by the general formula (1) and a polar fluorinated solvent. Next, the electron transport layer 17 is formed on the block layer 16. Next, an electron injection layer 18 and a cathode 19 are formed on the electron transport layer 17.
In addition, as above-mentioned as a formation method of each layer other than the block layer which comprises the organic EL element 10, any methods, such as a wet method, vapor deposition, and a sputtering, may be sufficient.

Finally, the element after forming the cathode 19 is sealed. As a sealing means used for sealing the element, known members and methods can be used.
The organic EL element 10 can be manufactured as described above.

  The materials, conditions, etc. used in the method for producing an organic EL element of the present invention will be described in detail below.

<Light emitting layer>
The light emitting layer is a layer that provides a field in which electrons and holes injected from an electrode or an adjacent layer are recombined to emit light via excitons. The light-emitting layer preferably contains a light-emitting dopant (a light-emitting dopant compound, a dopant compound, also simply referred to as a dopant) and a host compound (a matrix material, a light-emitting host compound, also simply referred to as a host).

  As a light emitting layer material such as a light emitting dopant and a host compound constituting these light emitting layers, a material that is soluble in a polar solvent other than the polar fluorinated solvent and insoluble in the polar fluorinated solvent is preferably used. All the light emitting layer materials described below satisfy this condition. Many of the conventionally known light emitting layer materials are insoluble in polar fluorinated solvents.

  The solvent used for the light emitting layer is preferably a polar solvent other than the polar fluorinated solvent, and the polar solvent other than the polar fluorinated solvent does not contain a fluorine atom in the solvent molecule and has a relative dielectric constant of 3 or more and 25 ° C. A hydrophilic solvent having a solubility in water of 5 g / L or more. Specifically, alcohols that do not contain fluorine such as methanol, ethanol, methoxyethanol, ethoxyethanol, propanol, butanol, pentanol, cyclohexanol, ethylene glycol, phenol, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, etc. Fluorine-free esters, acetonitrile, propionitrile, benzonitrile and other fluorine-free nitriles, acetone, butanone, cyclohexanone and other fluorine-free ketones, dimethyl ether, diethyl ether, methyl ethyl ether, dipropyl ether And ethers that do not contain fluorine, such as

  The light emitting layer material constituting the light emitting layer may be a compound having a molecular weight of 3000 or less. By using a compound having a molecular weight of 3000 or less, the solubility in a solvent is improved. However, according to the present invention, a block layer described later is formed on the light-emitting layer, so that it is composed of a light-emitting layer material having a molecular weight of 3000 or less. Another organic layer can be stacked on the light emitting layer without dissolving the light emitting layer.

  The molecular weight of the light emitting dopant and the host compound used as the light emitting layer material is not particularly limited, but the light emitting layer according to the present invention has a dibenzofuran ring, a dibenzothiophene ring or a carbazole ring, and an alkyl group. It is preferable to contain a compound having no alkenyl group, alkynyl group or arylalkyl group.

  There is no restriction | limiting in particular in the formation method of a light emitting layer, For example, it can form by a conventionally well-known vacuum evaporation method, a wet method, etc. Especially, it is preferable to form by a wet method from a viewpoint of reducing the manufacturing cost of an organic EL element.

  Examples of the wet method include spin coating, casting, ink jet, printing, die coating, blade coating, roll coating, spray coating, curtain coating, LB (Langmuir-Blodgett), and the like. Can be used. Among them, a method applicable to a roll-to-roll method such as a die coating method, a roll coating method, an ink jet method, or a spray coating method is preferable from the viewpoint of obtaining a homogeneous thin film easily and high productivity.

Examples of the liquid medium in which the light emitting layer material is dissolved or dispersed in the wet method include ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, halogenated hydrocarbons such as dichlorobenzene, toluene, xylene, and mesitylene. Aromatic hydrocarbons such as cyclohexylbenzene, aliphatic hydrocarbons such as cyclohexane, decalin, and dodecane, and organic solvents such as dimethylformamide (DMF) and dimethylsulfoxide (DMSO) can be used.
Further, when the light emitting layer material is dispersed in the liquid medium, it can be dispersed by a dispersion method such as ultrasonic wave, high shearing force dispersion or media dispersion.

Moreover, when employ | adopting a vapor deposition method as a formation method of a light emitting layer, although the vapor deposition conditions change with kinds etc. of the compound to be used, generally boat heating temperature 50-450 degreeC, vacuum degree 10 ^{< -6} > -10 ^<-2 > Pa, vapor deposition. It is desirable to appropriately select the speed within a range of 0.01 to 50 nm / second, a substrate temperature of −50 to 300 ° C., and a layer thickness of 0.1 nm to 5 μm, preferably 5 to 200 nm.

[1. Luminescent dopant]
As the luminescent dopant, a fluorescent luminescent dopant (also referred to as a fluorescent dopant or a fluorescent compound) or a phosphorescent dopant (also referred to as a phosphorescent dopant or a phosphorescent compound) is preferably used. The concentration of the light-emitting dopant in the light-emitting layer can be arbitrarily determined based on the specific dopant used and the device requirements. The concentration of the light emitting dopant may be contained at a uniform concentration in the thickness direction of the light emitting layer, or may have an arbitrary concentration distribution.

  The light emitting layer may contain a plurality of types of light emitting dopants. For example, a combination of dopants having different structures or a combination of a fluorescent luminescent dopant and a phosphorescent luminescent dopant may be used. Thereby, arbitrary luminescent colors can be obtained.

In the organic EL element, it is preferable that one or a plurality of light-emitting layers contain a plurality of light-emitting dopants having different emission colors and emit white light as a whole of the organic EL element. There are no particular limitations on the combination of light-emitting dopants that exhibit white, but examples include a combination of blue and orange, a combination of blue, green, and red. As the white color in the organic EL element, the chromaticity in the CIE 1931 color system at 1000 cd / m ² is x = 0.39 ± 0.09 when the 2 ° viewing angle front luminance is measured with a spectral radiance meter. = 0.38 ± 0.08 is preferable.

[1-1. Phosphorescent dopant]
The phosphorescent dopant is a compound in which light emission from an excited triplet is observed. Specifically, the phosphorescent dopant is a compound that emits phosphorescence at room temperature (25 ° C.), and has a phosphorescence quantum yield of 0 at 25 ° C. .01 or more compounds. In the phosphorescent dopant used for a light emitting layer, a preferable phosphorescence quantum yield is 0.1 or more.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. The phosphorescence quantum yield in a solution can be measured using various solvents. The phosphorescent dopant used in the light emitting layer may be any phosphorescent quantum yield (0.01 or more) in any solvent.

  The phosphorescent dopant can be appropriately selected from known materials used for the light emitting layer of the organic EL element.

  Among these, preferable phosphorescent dopants include organometallic complexes having Ir as a central metal. More preferably, a complex containing at least one coordination mode of a metal-carbon bond, a metal-nitrogen bond, a metal-oxygen bond, or a metal-sulfur bond is preferable.

[1-2. Fluorescent luminescent dopant]
The fluorescent light-emitting dopant is a compound that can emit light from an excited singlet, and is not particularly limited as long as light emission from the excited singlet is observed.

  Examples of the fluorescent light-emitting dopant include anthracene derivatives, pyrene derivatives, chrysene derivatives, fluoranthene derivatives, perylene derivatives, fluorene derivatives, arylacetylene derivatives, styrylarylene derivatives, styrylamine derivatives, arylamine derivatives, boron complexes, coumarin derivatives, Examples include pyran derivatives, cyanine derivatives, croconium derivatives, squalium derivatives, oxobenzanthracene derivatives, fluorescein derivatives, rhodamine derivatives, pyrylium derivatives, perylene derivatives, polythiophene derivatives, rare earth complex compounds, and the like.

Alternatively, a light emitting dopant utilizing delayed fluorescence may be used as the fluorescent light emitting dopant.
Specific examples of the luminescent dopant using delayed fluorescence include compounds described in, for example, International Publication No. 2011/156793, Japanese Patent Application Laid-Open No. 2011-213643, Japanese Patent Application Laid-Open No. 2010-93181, and the like.

[2. Host compound]
The host compound is a compound mainly responsible for charge injection and transport in the light emitting layer, and its own light emission is not substantially observed in the organic EL element.
Preferably, it is a compound having a phosphorescence quantum yield of phosphorescence emission of less than 0.1 at room temperature (25 ° C.), more preferably a compound having a phosphorescence quantum yield of less than 0.01. Moreover, it is preferable that the mass ratio in the layer is 20% or more among the compounds contained in a light emitting layer.

Moreover, it is preferable that the excited state energy of a host compound is higher than the excited state energy of the light emission dopant contained in the same layer.
A host compound may be used independently or may be used in combination of multiple types. By using a plurality of types of host compounds, it is possible to adjust the movement of electric charges, and it is possible to increase the efficiency of the organic EL element.

  There is no restriction | limiting in particular as a host compound used for a light emitting layer, The compound conventionally used with an organic EL element can be used. For example, a low molecular compound, a high molecular compound having a repeating unit, or a compound having a reactive group such as a vinyl group or an epoxy group may be used.

As a known host compound, while having a hole transport ability or an electron transport ability, it prevents the light emission from becoming longer wavelength, and further, from the viewpoint of stability against heat generation during driving of the organic EL element at high temperature or during element driving, It is preferable to have a high glass transition temperature (Tg). As a host compound, it is preferable that Tg is 80 degreeC or more, More preferably, it is 100 degreeC or more.
Here, a glass transition point (Tg) is a value calculated | required by the method based on JIS-K-7121 using DSC (Differential Scanning Colorimetry: Differential scanning calorimetry).

  Moreover, as a host compound, it is preferable that it is a compound whose solubility with respect to a polar fluorination solvent is lower than the compound which has a structure represented by General formula (1) from a viewpoint of the effect expression of this invention. Here, the solubility means the limit number of solute grams dissolved per liter of solvent at 25 ° C. and 1 atm.

《Block layer》
In the present invention, the block layer represents a layer inserted between the light-emitting layer and the electron transport layer, and transports electrons injected from the electron transport layer to the light-emitting layer side and is transported from the light-emitting layer side. It is a layer having a function of confining excitons generated by recombination of holes and electrons and holes on the light emitting layer in the light emitting layer. Therefore, the block layer functions as a so-called hole blocking layer.

  The block layer can be formed by applying a coating liquid for forming a block layer containing a compound having a structure represented by the general formula (1) and a polar fluorinated solvent. Thereby, when apply | coating the coating liquid for block layer formation and forming a block layer, it can suppress that a solvent melt | dissolves the light emitting layer which is a lower layer. Further, by forming the block layer, mixing of the light emitting layer and the electron transport layer is suppressed when forming the upper electron transport layer regardless of the vapor deposition method / coating method. Mixing and reaction of the light-emitting layer material and the electron transport layer material due to the energy of can be suppressed. For this reason, the performance fall of an organic EL element can be suppressed.

  Moreover, the electron transport layer application | coating which was difficult until now by making the coating liquid for block layer formation into the liquid composition containing the compound which has the structure represented by General formula (1), and a polar fluorination solvent Both the solubilization of the block layer material that can block the penetration of the electron transport layer forming coating solution into the light emitting layer during formation and the reduction of the influence of the solvent contained in the block layer forming coating solution on the light emitting layer. can do. Thereby, there is no need for a curing process for the lower layer and the block layer by high-temperature annealing or UV irradiation that distorts the substrate made of resin or the like, and an organic EL element can be manufactured inexpensively and stably.

Thereby, in the organic EL element of this invention, a block layer contains the compound and polar fluorinated solvent which have a structure represented by General formula (1).
Whether or not a polar fluorinated solvent is contained in the block layer can be determined as follows. That is, the distribution of the polar fluorinated solvent contained in the block layer of the organic EL device is analyzed by TOF-SIMS (time-of-flight secondary ion mass spectrometry), and the fluorine distribution in the layer thickness direction is measured (measurement). In this case, the ions are emitted from the substrate side, and care is taken so that the direction in which the component is implanted during ion collision does not coincide with the direction of solvent penetration during lamination. Thereby, when a fluorine atom is detected, it can be judged that the polar fluorinated solvent is contained in the block layer.

  Examples of the coating method for forming the block layer according to the present invention include spray coating, electrospray coating, ink jet, mist CVD, gravure coating, bar coating, roll coating, dip coating, screen printing, flexographic printing, and offset printing. Can be mentioned. Further, these coating methods include a case where the solvent is dried before the coating liquid for forming the block layer lands on the lower layer. The formation of the block layer by a coating method may be performed under any condition in the air or in an inert gas atmosphere. The block layer may be formed in a plurality of layers.

  The layer thickness of the block layer is preferably in the range of 1 to 100 nm, and more preferably in the range of 5 to 50 nm. When a plurality of block layers are formed, the total layer thickness is preferably within the above range. When the total thickness of the block layer is 1 nm or more, not only can the charge and exciton blocking functions be exhibited effectively, but also the effect that the penetration of the coating liquid for forming the upper layer (electron transport layer) can be more reliably suppressed can be obtained. It is done. Further, when the total layer thickness of the block layer is 100 nm or less, the effect of molecular orientation by the compound having the structure represented by the general formula (1) and the polar fluorinated solvent is easily obtained, and the upper layer (electron transport layer) material In addition to being able to more reliably suppress the penetration of the light, sufficient charge transportability can be ensured, and absorption and scattering of the emitted light can be suppressed to obtain high luminous efficiency as the entire organic EL element.

  The block layer may contain other materials other than the compound having the structure represented by the general formula (1) within a range not impairing the effects of the present invention. The content of the other material in the block layer is preferably 20% by mass or less with respect to the entire formed block layer, for example, although it depends on the type of material. If it is within this range, it is considered that the effects of the present invention can be prevented from being impaired.

[Compound having the structure represented by the general formula (1)]
The block layer can be formed using a coating solution containing a compound having a structure represented by the following general formula (1).

[In General Formula (1), X represents O, S or NR ₉ . R ₉ represents a hydrogen atom, a deuterium atom, an alkyl group, an alkenyl group, an alkynyl group, an arylalkyl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, or a non-aromatic heterocyclic ring. Represents a group or a substituent represented by the following general formula (2). R _{1 to} R ₈ are each a hydrogen atom, deuterium atom, halogen atom, cyano group, alkyl group, alkenyl group, alkynyl group, alkoxy group, acyl group, amino group, silyl group, phosphine oxide group, aromatic carbonization This represents a hydrogen ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, a non-aromatic heterocyclic group or a substituent represented by the following general formula (2). At least one of R _{1 to} R ₉ represents a substituent represented by the following general formula (2). R _{1 to} R ₉ may be the same as or different from each other, and may further have a substituent. ]

[In general formula (2), L represents an alkylene group, an alkenylene group, an o-phenylene group, an m-phenylene group, a p-phenylene group, an amide group or a divalent aromatic heterocyclic group, respectively, and further substituted. It may have a group. n represents an integer of 1 to 8. When n represents an integer of 2 or more, L of 2 or more may be the same as or different from each other. R is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a fluorinated alkyl group having 1 to 20 carbon atoms, an aromatic hydrocarbon ring group, an aromatic heterocyclic group or a non-aromatic group. Represents a hydrocarbon ring group, and may further have a substituent. m represents an integer of 1 to 3. At least one of L and R represents an alkylene group or an alkyl group. When there are a plurality of substituents represented by the general formula (2), L and R may be the same or different from each other, but they are not connected to each other to form a ring. ]

In the general formula (1), examples of the alkyl group represented by R _{1 to} R ₉ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a (t) butyl group, a pentyl group, a hexyl group, and an octyl group. , Dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, benzyl group and the like.
Examples of the alkenyl group represented by R _{1 to} R ₉ include those having one or more double bonds in the alkyl group, and more specifically, vinyl groups, allyl groups, 1- Examples include a propenyl group, an isopropenyl group, a 2-butenyl group, a 1,3-butadienyl group, a 2-pentenyl group, and a 2-hexenyl group.
Examples of the alkynyl group represented by R _{1 to} R ₉ include ethynyl group, acetylenyl group, 1-propynyl group, 2-propynyl group (propargyl group), 1-butynyl group, 2-butynyl group, 3- Butynyl group, 1-pentynyl group, 2-pentynyl group, 3-pentynyl group, 1-hexynyl group, 2-hexynyl group, 3-hexynyl group, 1-heptynyl group, 2-heptynyl group, 5-heptynyl group, 1- Examples include an octynyl group, a 3-octynyl group, and a 5-octynyl group.

In the general formula (1), examples of the aromatic hydrocarbon ring group (also referred to as an aryl group) represented by R _{1 to} R ₉ include a phenyl group, a p-chlorophenyl group, a mesityl group, a tolyl group, and a xylyl group. Group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group and the like.
Examples of the aromatic heterocyclic group represented by R _{1 to} R ₉ include a pyridyl group, a pyrimidinyl group, a furyl group, a pyrrolyl group, an imidazolyl group, a benzoimidazolyl group, a pyrazolyl group, a pyrazinyl group, and a triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl Group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (one of the carbon atoms constituting the carboline ring of the carbolinyl group is Is replaced by a nitrogen atom.), Quinoxalinyl group, pyri Jiniru group, triazinyl group, quinazolinyl group, and phthalazinyl group.

In the general formula (1), examples of the non-aromatic hydrocarbon ring group represented by R _{1 to} R ₉ include a cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), a cycloalkoxy group (for example, cyclopentyl). An oxy group, a cyclohexyloxy group, etc.), a cycloalkylthio group (eg, a cyclopentylthio group, a cyclohexylthio group, etc.), a tetrahydronaphthalene ring, a 9,10-dihydroanthracene ring, a biphenylene ring, etc. Can be mentioned.
Examples of the non-aromatic hydrocarbon ring group represented by R _{1 to} R ₉ include an epoxy ring, an aziridine ring, a thiirane ring, an oxetane ring, an azetidine ring, a thietane ring, a tetrahydrofuran ring, a dioxolane ring, a pyrrolidine ring, Pyrazolidine ring, imidazolidine ring, oxazolidine ring, tetrahydrothiophene ring, sulfolane ring, thiazolidine ring, ε-caprolactone ring, ε-caprolactam ring, piperidine ring, hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydro Pyran ring, 1,3-dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiopyran ring, thiomorpholine ring, thiomorpholine-1,1-dioxide ring, pyranose ring, diazabicyclo [2,2,2] -Octane ring, pheno And monovalent groups derived from a xazine ring, phenothiazine ring, oxanthrene ring, thioxanthene ring, phenoxathiin ring, and the like.

In the general formula (1), examples of the alkoxy group represented by R _{1 to} R ₈ include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, 2- Ethylhexyloxy, octyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tridecyloxy, tetradecyloxy, pentadecyloxy, hexadecyloxy, heptadecyloxy, octadecyloxy Groups and the like.
Examples of the acyl group represented by R _{1 to} R ₈ include an acetyl group, an ethylcarbonyl group, a propylcarbonyl group, a pentylcarbonyl group, a cyclohexylcarbonyl group, an octylcarbonyl group, a 2-ethylhexylcarbonyl group, and a dodecylcarbonyl group. , Phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group and the like.
Examples of the amino group represented by R _{1 to} R ₈ include an amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, A naphthylamino group, 2-pyridylamino group, etc. are mentioned.
Examples of the silyl group represented by R _{1 to} R ₈ include a trimethylsilyl group, a triisopropylsilyl group, a triphenylsilyl group, and a phenyldiethylsilyl group.
Examples of the phosphine oxide group represented by R _{1 to} R ₈ include a diphenylphosphine oxide group, a ditolylphosphine oxide group, a dimethylphosphine oxide group, a dinaphthylphosphine oxide group, and 9,10-dihydro-9-oxa. A -10-phosphaphenanthrene-10-oxide group can be exemplified.

In the general formula (1), examples of the arylalkyl group represented by R ₉ include a benzyl group, a phenethyl group, a diphenylmethyl group, a 1,1-diphenylethyl group, a 1,2-diphenylethyl group, and a tolyl group. And an ethylphenyl group.

In the general formula (1), examples of the substituent that the groups represented by R _{1 to} R ₉ may further include an alkyl group (for example, a methyl group, an ethyl group, and a propyl group). Isopropyl group, (t) butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, benzyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group etc.), Alkenyl groups (for example, vinyl groups, allyl groups, etc.), alkynyl groups (for example, propargyl groups, etc.), aromatic hydrocarbon groups (also called aryl groups, for example, phenyl groups, p-chlorophenyl groups, mesityl groups, tolyl groups, Xylyl, naphthyl, anthryl, azulenyl, acenaphthenyl, fluorenyl, phenanthryl, in Nyl group, pyrenyl group, biphenylyl group, etc.), heterocyclic group (for example, epoxy ring, aziridine ring, thiirane ring, oxetane ring, azetidine ring, thietane ring, tetrahydrofuran ring, dioxolane ring, pyrrolidine ring, pyrazolidine ring, imidazolidine ring Oxazolidine ring, tetrahydrothiophene ring, sulfolane ring, thiazolidine ring, ε-caprolactone ring, ε-caprolactam ring, piperidine ring, hexahydropyridazine ring, hexahydropyrimidine ring, piperazine ring, morpholine ring, tetrahydropyran ring, 1,3 -Dioxane ring, 1,4-dioxane ring, trioxane ring, tetrahydrothiopyran ring, thiomorpholine ring, thiomorpholine 1,1-dioxide ring, pyranose ring, diazabicyclo [2,2,2] -octane ring), aromatic Family complex Groups (pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3- Triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group , Indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (in which one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group , Quinazolinyl group, phthalazini Group), halogen atom (eg chlorine atom, bromine atom, iodine atom, fluorine atom etc.), alkoxy group (eg methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, Dodecyloxy group etc.), cycloalkoxy group (eg cyclopentyloxy group, cyclohexyloxy group etc.), aryloxy group (eg phenoxy group, naphthyloxy group etc.), alkylthio group (eg methylthio group, ethylthio group, propylthio group) , Pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group etc.), arylthio group (eg, phenylthio group, naphthylthio group etc.), alkoxycarbonyl group (eg, Methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, Aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylurea) Group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, Octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group) Group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group) Propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, amino Carbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, Naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), sulfinyl group (eg, methylsulfinyl group, Tylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group or arylsulfonyl group (for example, methylsulfonyl Group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino) Group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, diarylamino group (for example, Diphenylamino group, dinaphthylamino group, phenylnaphthylamino group, etc.), naphthylamino group, 2-pyridylamino group, etc.), nitro group, cyano group, hydroxy group, mercapto group, alkylsilyl group or arylsilyl group (for example, trimethylsilyl group) Group, triethylsilyl group, (t) butyldimethylsilyl group, triisopropylsilyl group, (t) butyldiphenylsilyl group, triphenylsilyl group, trinaphthylsilyl group, 2-pyridylsilyl group), alkylphosphino group or Arylphosphino group (dimethylphosphino group, diethylphosphino group, dicyclohexylphosphino group, methylphenylphosphino group, diphenylphosphino group, dinaphthylphosphino group, di (2-pyridyl) phosphino group), alkylphosphoryl group Or ants Ruphosphoryl group (dimethylphosphoryl group, diethylphosphoryl group, dicyclohexylphosphoryl group, methylphenylphosphoryl group, diphenylphosphoryl group, dinaphthylphosphoryl group, di (2-pyridyl) phosphoryl group), alkylthiophosphoryl group or arylthiophosphoryl group (dimethylthio) It represents any group selected from a phosphoryl group, a diethylthiophosphoryl group, a dicyclohexylthiophosphoryl group, a methylphenylthiophosphoryl group, a diphenylthiophosphoryl group, a dinaphthylthiophosphoryl group, and a di (2-pyridyl) thiophosphoryl group). In addition, these substituents may be further substituted by the above-mentioned substituents, and they may be condensed with each other to further form a ring.

In the general formula (2), examples of the alkylene group represented by L include a methylene group, an ethylene group, a trimethylene group, a propylene group, a butylene group, a butane-1,2-diyl group, and a hexylene group. .
Examples of the alkenylene group represented by L include a vinylene group, a propenylene group, a butenylene group, a pentenylene group, a 1-methylvinylene group, a 1-methylpropenylene group, a 2-methylpropenylene group, and a 1-methylpentene. Examples include a tenylene group, a 3-methylpentenylene group, a 1-ethylvinylene group, a 1-ethylpropenylene group, a 1-ethylbutenylene group, and a 3-ethylbutenylene group.
Examples of the amide group represented by L include a methylcarbonylamino group, an ethylcarbonylamino group, a dimethylcarbonylamino group, a propylcarbonylamino group, a pentylcarbonylamino group, a cyclohexylcarbonylamino group, and a 2-ethylhexylcarbonylamino group. Octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, and the like.
As the divalent aromatic heterocyclic group represented by L, such as are derived from those cited as the aromatic heterocyclic group represented by R ₁ to R ₉ in the general formula (1) A divalent group is mentioned.

In the general formula (2), examples of the alkyl group having 1 to 20 carbon atoms represented by R include those exemplified as the alkyl group represented by R _{1 to} R ₉ in the general formula (1). Among them, groups having 1 to 20 carbon atoms can be mentioned.
As a C1-C20 fluorinated alkyl group represented by R, the group which the hydrogen atom of the said C1-C20 alkyl group substituted to the fluorine atom is mentioned, for example.
Examples of the alkoxy group having 1 to 20 carbon atoms represented by R include those exemplified as the alkoxy group represented by R _{1 to} R ₈ in the general formula (1) having 1 to 1 carbon atoms. There are 20 groups.
As the aromatic hydrocarbon ring group, aromatic heterocyclic group or non-aromatic hydrocarbon ring group represented by R, for example, the aromatic hydrocarbon represented by R _{1 to} R ₉ in the above general formula (1) The same thing as a cyclic group, an aromatic heterocyclic group, or a non-aromatic hydrocarbon cyclic group is mentioned.

In the general formula (2), examples of the substituent that L and R may further have are the same as the substituents that R _{1 to} R ₉ may have in the general formula (1). Things.

  As the compound having the structure represented by the general formula (1), among the substituents represented by the general formula (2), those in which at least one L is an alkylene group having 1 to 6 carbon atoms are preferable. Of the substituents represented by the general formula (2), at least one R is preferably an alkyl group having 1 to 6 carbon atoms.

  Hereinafter, although the specific example of a compound which has a structure represented by General formula (1) based on this invention is shown, it is not restricted to these.

[Polar fluorinated solvent]
In the method for producing an organic EL element of the present invention, a polar fluorinated solvent is used for forming the block layer. Moreover, it is preferable that a polar fluorinated solvent is used also for formation of an electron carrying layer.
Here, the polar fluorinated solvent refers to a solvent containing a fluorine atom in a solvent molecule and having a relative dielectric constant of 3 or more and a solubility in water at 25 ° C. of 5 g / L or more.

  The boiling point of the polar fluorinated solvent is preferably in the range of 50 to 200 ° C. By setting the temperature to 50 ° C. or higher, the occurrence of unevenness due to the heat of evaporation during drying of the coating film can be more reliably suppressed. By setting the temperature to 200 ° C. or lower, the solvent can be quickly dried, and the solvent content in the formed layer is reduced, so that crystal growth in the layer can be more reliably suppressed, and the solvent escape route is rough. Therefore, the density is improved and the current efficiency can be increased. More preferably, it exists in the range of 70-150 degreeC.

The water content of the polar fluorinated solvent is preferably as low as possible since it becomes a luminescence quencher even if it is a very small amount, and is preferably 100 ppm or less, and more preferably 20 ppm or less.
Similarly, the content of impurities other than moisture in the polar fluorinated solvent is similarly good even if it is a very small amount, because it becomes a quencher for light emission or causes deterioration of film quality after bubbles or drying. Preferably, it is 20 ppm or less. Examples of impurities other than moisture include oxygen, inert gases such as nitrogen, argon and carbon dioxide, catalysts used during preparation and purification, inorganic compounds or metals brought in from adsorbents and instruments, and the like.

As the polar fluorinated solvent, for example, fluorinated alcohol, fluorinated acrylate, fluorinated methacrylate, fluorinated ester, fluorinated ether or fluorinated hydroxyalkylbenzene, and fluorinated amine are preferable, and fluorinated alcohol, fluorinated ester or fluorinated Ether is more preferable, and fluorinated alcohol is more preferable from the viewpoints of solubility and drying properties.
The number of carbon atoms of the fluorinated alcohol is preferably 3 to 5 carbon atoms from the viewpoint of boiling point and material solubility.

  Examples of the fluorine substitution position include the position of hydrogen in the case of alcohol, and the fluorination rate may be any degree that does not impair the solubility of the layer material, and is fluorinated to the extent that the lower layer material is not eluted. It is desirable.

Examples of the fluorinated alcohol include 1H, 1H-pentafluoropropanol, 6- (perfluoroethyl) hexanol, 1H, 1H-heptafluorobutanol, 2- (perfluorobutyl) ethanol (FBEO), 3- (perfluoro Butyl) propanol, 6- (perfluorobutyl) hexanol, 2-perfluoropropoxy-2,3,3,3-tetrafluoropropanol, 2- (perfluorohexyl) ethanol, 3- (perfluorohexyl) propanol, 6 -(Perfluorohexyl) hexanol, 1H, 1H- (perfluorohexyl) hexanol, 6- (perfluoro-1-methylethyl) hexanol, 1H, 1H, 3H-tetrafluoropropanol (TFPO), 1H, 1H, 5H -Octafull Lopentanol (OFAO), 1H, 1H, 7H-dodecafluoroheptanol (DFHO), 2H-hexafluoro-2-propanol, 1H, 1H, 3H-hexafluorobutanol (HFBO), 2,2,3,3,4 , 4,5,5-octafluoro-1,6-hexanediol, 2,2-bis (trifluoromethyl) propanol, 1H, 1H-trifluoroethanol (TFEO) and the like. From the viewpoint of the solubility of the material, TFPO, OFAO and HFBO are preferable.
Examples of the fluorinated ether include hexafluorodimethyl ether, perfluorodimethoxymethane, perfluorooxetane, perfluoro-1,3-dioxolane, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetra. Examples include fluoropropyl ether.
Examples of the fluorinated ester include methyl perfluorobutyrate, ethyl perfluorobutyrate, methyl perfluoropropionate, methyl difluoroacetate, ethyl difluoroacetate, methyl-2-trifluoromethyl-3,3,3- Examples thereof include trifluoropropionate.

In the coating liquid for forming the block layer, the content of the compound having the structure represented by the general formula (1) of the present invention is 0.05 to 10% by mass, and the content of the polar fluorinated solvent is 90 to 99.95%. % Is preferred.
The polar fluorinated solvent may be a mixed solvent of two or more polar fluorinated solvents or a mixture of a polar fluorinated solvent and a solvent other than the polar fluorinated solvent as long as it does not dissolve the light emitting layer material. A solvent may be used. For example, a mixed solvent of fluorinated alcohol and alcohol can be used. When using a mixed solvent, the content of the polar fluorinated solvent is preferably 50% by mass or more.

  In the organic EL device of the present invention, the polar fluorinated solvent is preferably contained in an amount of 1000 ppm by mass or less as the entire constituent layers. By making it within this range, the organic EL element material is reoriented by energy such as heat generated at the time of driving without deteriorating the charge transfer between the organic EL element materials, and the crystal grain boundary charges are not re-oriented. Transportability is not reduced by the trap.

In the organic EL device of the present invention, the content of the polar fluorinated solvent as a whole of each constituent layer can be measured as follows.
First, the sample which formed each layer from a positive hole injection layer to an electron carrying layer on a 30 mm square glass substrate similarly to the organic EL element of a measuring object is produced. Two samples of about 1 cm mouth are cut out from the flat film portion of this sample. One of them is a part of the whole layer from the hole injection layer to the electron transport layer, which is stripped with a clean wiper soaked in toluene, to make a step, and after sputtering an Ag thin film with SC-701 MkII ECO manufactured by Sanyu Electronics, Veeco The step is measured using WYKO manufactured by KK and the film thickness is determined. Further, in the other sample cut out, the entire layer from the hole injection layer to the electron transport layer is removed by immersion in toluene, and the film area is determined from the weight ratio before and after the removal. The sample whose area was determined was measured with a temperature-programmed thermal desorption analyzer manufactured by Denshi Kagaku Co., and the desorbed gas component was quantified from the mass fragment spectrum corresponding to the polar fluorinated solvent used for forming the layer. The mass ratio of the polar fluorinated solvent per volume of the organic layer laminate is determined. As described above, the content of the polar fluorinated solvent can be determined.

"Base material"
There is no limitation in particular in the material of the base material used for an organic EL element, Preferably, glass, quartz, a resin film etc. can be mentioned, for example. Particularly preferred is a resin film capable of giving flexibility to the organic EL element.

  Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate (TAC), cellulose acetate butyrate, cellulose acetate propionate ( CAP), cellulose esters such as cellulose acetate phthalate, cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones, Cycloolefins such as polyether imide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic or polyarylate, arton (trade name, manufactured by JSR) or appel (trade name, manufactured by Mitsui Chemicals) Examples thereof include a resin film.

A gas barrier film may be formed on the surface of the resin film using an inorganic or organic coating or a hybrid coating of both. The gas barrier membrane has a water vapor permeability (25 ± 0.5 ° C., humidity (90 ± 2)% RH) measured by a method according to JIS K 7129-1992 of 0.01 g / (m ² · 24 h) or less. It is preferable that it is a gas barrier film. Furthermore, the oxygen permeability measured by a method according to JIS K 7126-1987 is 1 × 10 ⁻³ mL / (m ² · 24 h · atm) or less, and the water vapor permeability is 1 × 10 ⁻⁵ g / A high gas barrier film of (m ² · 24 h) or less is preferable.

  As a material for forming the gas barrier film, any material having a function of suppressing intrusion of moisture, oxygen, or the like may be used. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Furthermore, in order to improve the brittleness of the gas barrier film, it is more preferable to have a laminated structure of these inorganic layers and layers made of organic materials. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

  The method for forming the gas barrier film is not particularly limited. For example, the vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used. For example, an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is preferable.

《Electron transport layer》
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, the electron injection layer is also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.
Moreover, it is preferable to form an electron carrying layer using the coating liquid containing the electron carrying material demonstrated below. The coating solution preferably contains a polar fluorinated solvent. The solubility in a polar fluorinated solvent is preferably decreased in the order of the electron transport layer material, the block layer material, and the light emitting layer material.

  Conventionally, as an electron transport material used for an electron transport layer (in the case of a plurality of layers, an electron transport layer adjacent to the cathode side), the electron transport material only needs to have a function of transmitting electrons injected from the cathode to the light emitting layer. As the material, any one of conventionally known compounds can be selected and used. Examples thereof include metal complexes such as a fluorene derivative, a carbazole derivative, an azacarbazole derivative, an oxadiazole derivative, a triazole derivative, a silole derivative, a pyridine derivative, a pyrimidine derivative, and an 8-quinolinol derivative.

In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transport material.
Among these, a carbazole derivative, an azacarbazole derivative, a pyridine derivative, and the like are preferable in the present invention, and an azacarbazole derivative is more preferable.

  The electron transport layer can be formed by thinning the electron transport material by a known method such as a spin coating method, a casting method, a printing method including an ink jet method, an LB method, and the like, preferably It can be formed by a wet process using a coating solution containing an electron transport material and a fluorinated alcohol solvent.

  Although there is no restriction | limiting in particular about the layer thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  In addition to the electron transport material, an electron transport layer having high n property in which an impurity is doped as a guest material can also be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

  The electron transport layer in the present invention preferably contains an organic alkali metal salt. There are no particular restrictions on the type of organic substance, but formate, acetate, propionic acid, butyrate, valerate, caproate, enanthate, caprylate, oxalate, malonate, succinate Benzoate, phthalate, isophthalate, terephthalate, salicylate, pyruvate, lactate, malate, adipate, mesylate, tosylate, benzenesulfonate , Preferably formate, acetate, propionate, butyrate, valerate, caprate, enanthate, caprylate, oxalate, malonate, succinate, benzoate, more preferably Is preferably an alkali metal salt of an aliphatic carboxylic acid such as formate, acetate, propionate or butyrate, and the aliphatic carboxylic acid preferably has 4 or less carbon atoms. Most preferred is acetate.

The kind of alkali metal of the organic alkali metal salt is not particularly limited, and examples thereof include Na, K, Cs, and Li, preferably K, Cs, and more preferably Cs. Examples of the alkali metal salt of the organic substance include a combination of the organic substance and the alkali metal, preferably, formic acid Li, formic acid K, formic acid Na, formic acid Cs, acetic acid Li, acetic acid K, Na acetate, acetic acid Cs, propionic acid Li, Propionic acid Na, propionic acid K, propionic acid Cs, oxalic acid Li, oxalic acid Na, oxalic acid K, oxalic acid Cs, malonic acid Li, malonic acid Na, malonic acid K, malonic acid Cs, succinic acid Li, succinic acid Na, succinic acid K, succinic acid Cs, benzoic acid Li, benzoic acid Na, benzoic acid K, benzoic acid Cs, more preferably Li acetate, K acetate, Na acetate, Cs acetate, most preferably Cs acetate.
The content of these dope materials is preferably 1.5 to 35% by mass, more preferably 3 to 25% by mass, and most preferably 5 to 15% by mass with respect to the electron transport layer to be added.

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

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

  As the hole transport material, those described above can be used, but porphyrin compounds, aromatic tertiary amine compounds and styrylamine compounds can be used, and in particular, aromatic tertiary amine compounds can be used. preferable.

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ′, N′-tetraphenyl-4,4′-diaminophenyl, N, N′-diphenyl-N, N′— Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (abbreviation: TPD), 2,2-bis (4-di-p-tolylaminophenyl) propane, 1,1 -Bis (4-di-p-tolylaminophenyl) cyclohexane, N, N, N ', N'-tetra-p-tolyl-4,4'-diaminobiphenyl, 1,1-bis (4-di-p -Tolylaminophenyl) -4-phenylcyclohexane, bis (4-dimethylamino-2-methylphenyl) phenylmethane, bis (4-di-p-tolylaminophenyl) phenylmethane, N, N'-diphenyl-N, '-Di (4-methoxyphenyl) -4,4'-diaminobiphenyl, N, N, N', N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis (diphenylamino) c Audriphenyl, N, N, N-tri (p-tolyl) amine, 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene, 4-N, N- Examples include diphenylamino- (2-diphenylvinyl) benzene, 3-methoxy-4′-N, N-diphenylaminostilbenzene, N-phenylcarbazole and the like. Furthermore, those having two condensed aromatic rings described in US Pat. No. 5,061,569 in the molecule, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] Biphenyl (abbreviation: NPD), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) in which triphenylamine units described in JP-A-4-308688 are linked in a three star burst type ) -N-phenylamino] triphenylamine (abbreviation: MTDATA).

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

  JP-A-11-251067, J. Org. Huang et. al. , Applied Physics Letters, 80 (2002), p. A so-called p-type hole transport material as described in 139 can also be used. In the present invention, these materials are preferably used from the viewpoint of obtaining a light-emitting element with higher efficiency.

  For the hole transport layer, known methods such as vacuum deposition, spin coating, casting, printing including ink jet, and LB (Langmuir Brodget, Langmuir Broadgett) are used as the hole transport material. Thus, it can be formed by thinning. Although there is no restriction | limiting in particular about the layer thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it exists in the range of 5-200 nm. This hole transport layer may have a single layer structure composed of one or more of the above materials.

  Moreover, p property can also be made high by doping the material of a positive hole transport layer with an impurity. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175 and J.P. Appl. Phys. 95, 5773 (2004), and the like.

  Thus, it is preferable to increase the p property of the hole transport layer because an element with lower power consumption can be manufactured.

<Injection layer>
An injection layer (a hole injection layer and an electron injection layer) is a layer provided between an electrode and a light-emitting layer in order to reduce drive voltage or improve light emission luminance. The details are described in Chapter 2, “Electrode Materials” (pp. 123-166) of Volume 2 of “November 30, 1998, issued by NTS Corporation”. There is.

  The injection layer can be provided as necessary. If it is a hole injection layer, it may exist between the anode and the light emitting layer or the hole transport layer, and if it is an electron injection layer, it may exist between the cathode and the light emitting layer or the electron transport layer.

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

  The details of the electron injection layer are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, a metal layer represented by strontium, aluminum, or the like. And an alkali metal halide layer typified by potassium fluoride, an alkaline earth metal compound layer typified by magnesium fluoride, and an oxide layer typified by molybdenum oxide. In the present invention, the electron injection layer is preferably a very thin film, and although depending on the constituent material, the layer thickness is preferably in the range of 1 nm to 10 μm.

《Electron blocking layer》
The electron blocking layer has a function of a hole transport layer in a broad sense. The electron blocking layer is made of a material that has the ability to transport holes and has a very small ability to transport electrons. By blocking holes while transporting holes, the probability of recombination of electrons and holes is improved. Can be made. Moreover, the structure of a positive hole transport layer can be used as an electron blocking layer as needed. The layer thickness of the hole blocking layer applied to the present invention is preferably in the range of 3 to 100 nm, and more preferably in the range of 5 to 30 nm.

"anode"
As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such an electrode substance include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , ZnO, and IZO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) that can form a transparent conductive film may be used. For the anode, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method. When pattern accuracy is not so high (about 100 μm or more) A pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of the electrode material. Moreover, when using the substance which can be apply | coated like an organic electroconductivity compound, wet film forming methods, such as a printing system and a coating system, can also be used. When light emission is extracted from the anode, it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected within the range of 10 to 1000 nm, preferably within the range of 10 to 200 nm.

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

  Moreover, after producing the metal with a film thickness of 1 to 20 nm on the cathode, a transparent or translucent cathode can be produced by producing the conductive transparent material mentioned in the description of the anode on the cathode, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

<Sealing>
Examples of the sealing means used for sealing the organic EL element of the present invention include a method of bonding a sealing member, an electrode, and a support substrate with an adhesive.

  The sealing member may be disposed so as to cover the display area of the organic EL element, and may be concave or flat. Moreover, transparency and electrical insulation are not particularly limited.

  Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.

In the present invention, a polymer film and a metal film can be preferably used because the organic EL element can be thinned. Furthermore, the polymer film preferably has an oxygen permeability of 10 ⁻³ g / (m ² · 24 h) or less and a water vapor permeability of 10 ⁻³ g / (m ² · 24 h) or less. Moreover, it is more preferable that both the water vapor permeability and the oxygen permeability are 10 ⁻⁵ g / (m ² · 24 h) or less.

  For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used. Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to. Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

  A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.

  In addition, it is also preferable to coat the electrode and the organic layer on the outside of the electrode facing the support substrate with the organic layer interposed therebetween, and form an inorganic or organic layer in contact with the support substrate to form a sealing film. it can. In this case, as a material for forming the film, any material may be used as long as it has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like may be used. it can. Furthermore, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials. The method for forming these films is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster-ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

  In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil is injected in the gas phase and the liquid phase. Is preferred. A vacuum can also be used. Moreover, a hygroscopic compound can also be enclosed inside.

  Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg, calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide, etc.), perchloric acids (eg, barium perchlorate) , Magnesium perchlorate, etc.), and anhydrous salts are preferably used in sulfates, metal halides and perchloric acids.

《Protective film, protective plate》
In order to increase the mechanical strength of the element, a protective film or a protective plate may be provided outside the sealing film or sealing film on the side facing the support substrate with the organic layer interposed therebetween. In particular, when sealing is performed with a sealing film, the mechanical strength is not necessarily high, and thus it is preferable to provide such a protective film and a protective plate. As a material that can be used for this, the same glass plate, polymer plate / film, metal plate / film, etc. used for the sealing can be used, but the polymer film is light and thin. Is preferably used.

<Application>
Since the organic EL element of the embodiment described above is a surface light emitter, it can be used as various light emission sources. For example, lighting devices such as home lighting and interior lighting, backlights for clocks and liquid crystals, lighting for billboard advertisements, light sources for traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, Examples include, but are not limited to, a light source of an optical sensor, and can be effectively used as a backlight of a liquid crystal display device combined with a color filter and a light source for illumination.

  Hereinafter, although an example is given and the present invention is explained concretely, the present invention is not limited to these. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "mass part" or "mass%" is represented.

  The solvents used in the following examples are shown in Table 1.

  Moreover, the block layer material of the comparative example used in each following example is shown below.

[Example 1]
<< Production of Organic EL Element 101 >>
As shown below, the anode / hole injection layer / hole transport layer / light emitting layer / blocking layer / electron transport layer / electron injection layer / cathode are laminated and sealed on the base material to form a bottom emission type organic material. An EL element 101 was produced.

(Preparation of base material)
First, an atmospheric pressure plasma discharge treatment apparatus having a configuration described in Japanese Patent Application Laid-Open No. 2004-68143 is used on the entire surface of a polyethylene naphthalate film (manufactured by Teijin DuPont, hereinafter abbreviated as PEN) on the side where the anode is formed. Then, an inorganic gas barrier layer made of SiO _x was formed to a thickness of 500 nm. Thus, a flexible base material having a gas barrier property with an oxygen permeability of 0.001 mL / (m ² · 24 h) or less and a water vapor permeability of 0.001 g / (m ² · 24 h) or less was produced.

(Formation of anode)
An ITO (indium tin oxide) film having a thickness of 120 nm was formed on the substrate by sputtering, and patterned by photolithography to form an anode. The pattern was such that the area of the light emitting region was 5 cm × 5 cm.

(Formation of hole injection layer)
The substrate on which the anode was formed was subjected to ultrasonic cleaning with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed for 5 minutes. Then, a dispersion of poly (3,4-ethylenedioxythiophene) / polystyrene sulfonate (PEDOT / PSS) prepared in the same manner as in Example 16 of Japanese Patent No. 4509787 was formed on the base material on which the anode was formed. The 2% by weight solution diluted in (1) was applied by a die coating method and naturally dried to form a hole injection layer having a layer thickness of 40 nm.

(Formation of hole transport layer)
Next, the base material on which the hole injection layer was formed was transferred to a nitrogen atmosphere using nitrogen gas (grade G1), and a coating liquid for forming a hole transport layer having the following composition was used to form a 5 m / After being applied for min and dried naturally, it was held at 130 ° C. for 30 minutes to form a hole transport layer having a layer thickness of 30 nm.

<Coating liquid for hole transport layer formation>
Hole transport material (the following compound (60)) (weight average molecular weight Mw = 80000)
10 parts by mass Chlorobenzene 3000 parts by mass

(Formation of light emitting layer)
Next, the base material on which the hole transport layer was formed was applied at 5 m / min by a die coating method using a light emitting layer forming coating solution having the following composition, naturally dried, and then held at 120 ° C. for 30 minutes. A light emitting layer having a layer thickness of 50 nm was formed.

<Light emitting layer forming coating solution>
Host compound S-5 9 parts by mass Phosphorescent dopant D-76 1 part by mass Isopropyl acetate 2000 parts by mass

(Formation of block layer)
Next, the base material on which the light-emitting layer was formed was applied at 5 m / min by a die coating method using a coating solution for forming a block layer having the following composition, naturally dried, and then kept at 80 ° C. for 30 minutes to obtain a layer thickness. A 10 nm block layer was formed.

<Block layer forming coating solution>
HS-1 2 parts by mass IPA 1500 parts by mass OFAO 500 parts by mass

(Formation of electron transport layer)
Next, the base material on which the block layer was formed was applied at 5 m / min by a die coating method using a coating liquid for forming an electron transport layer having the following composition, naturally dried, and then held at 80 ° C. for 30 minutes, An electron transport layer having a thickness of 30 nm was formed.

<Coating liquid for electron transport layer formation>
The following compound A 6 mass parts TFPO 2000 mass parts

(Formation of electron injection layer and cathode)
Subsequently, the substrate was attached to a vacuum deposition apparatus without being exposed to the atmosphere. Moreover, what put sodium fluoride and potassium fluoride in the resistance heating boat made from molybdenum was attached to the vacuum evaporation system, and the vacuum tank was pressure-reduced to 4 * 10 < ^-5 > Pa. Thereafter, the boat was energized and heated, and sodium fluoride was deposited on the electron transport layer at 0.02 nm / second to form a thin film having a thickness of 1 nm. Similarly, potassium fluoride was vapor-deposited on the sodium fluoride thin film at 0.02 nm / second to form an electron injection layer having a layer thickness of 1.5 nm.
Subsequently, aluminum was deposited to form a cathode having a thickness of 100 nm.

(Sealing)
The sealing base material was adhere | attached on the laminated body formed by the above process using the commercially available roll laminating apparatus.
Adhesion as a sealing substrate with a thickness of 1.5 μm using a flexible aluminum foil (manufactured by Toyo Aluminum Co., Ltd.) with a thickness of 30 μm using a two-component reaction type urethane adhesive for dry lamination. An agent layer was provided, and a laminate of a polyethylene terephthalate (PET) film having a thickness of 12 μm was prepared.

  A thermosetting adhesive as a sealing adhesive was uniformly applied at a thickness of 20 μm along the adhesive surface (shiny surface) of the aluminum foil of the sealing substrate using a dispenser. This was dried under a vacuum of 100 Pa or less for 12 hours. Furthermore, the sealing substrate is moved to a nitrogen atmosphere having a dew point temperature of −80 ° C. or lower and an oxygen concentration of 0.8 ppm, and is dried for 12 hours or more so that the moisture content of the sealing adhesive is 100 ppm or lower. It was adjusted.

As the thermosetting adhesive, an epoxy adhesive mixed with the following (A) to (C) was used.
(A) Bisphenol A diglycidyl ether (DGEBA)
(B) Dicyandiamide (DICY)
(C) Epoxy adduct curing accelerator

The sealing substrate was closely attached to the laminate, and was tightly sealed using a pressure-bonding roll under pressure-bonding conditions of a pressure-rolling roll temperature of 100 ° C., a pressure of 0.5 MPa, and an apparatus speed of 0.3 m / min. .
As described above, an organic EL element 101 having the same form as the organic EL element having the configuration shown in FIG. 1 was manufactured.

<< Production of Organic EL Elements 102 to 145 >>
In preparation of the said organic EL element 101, except having changed the material and solvent contained in the coating liquid for block layer formation, and the solvent contained in the coating liquid for electron transport layer formation as shown in Table 2 and Table 3. Similarly, organic EL elements 102 to 145 were produced. In addition, when several types of solvent contained in the coating liquid for block layer formation, it adjusted so that total content might be 2000 mass parts.

<< Evaluation of Organic EL Elements 101-145 >>
The following evaluation was performed about the organic EL elements 101-145 produced as mentioned above. The evaluation results are shown in Tables 2 and 3.

(1) Measurement of luminous efficiency Luminous efficiency is measured at room temperature (25 ° C) at a constant current density of ^2.5 mA / cm ² and a spectral radiance meter CS-2000 (manufactured by Konica Minolta). Was used to measure the light emission luminance of each element, and the light emission efficiency (external extraction efficiency) at the current value was determined. It represents with the relative value which sets the luminous efficiency of the organic EL element 145 (comparative example) to 100.

(2) Measurement of luminescence lifetime The luminescence lifetime is measured by continuously driving an organic EL element under conditions of room temperature 25 ° C. and humidity 55% RH, and measuring the luminance using the spectral radiance meter CS-2000. The time (half life) during which the brightness was reduced by half was determined as a measure of life. The driving condition was set to a current value of 10,000 cd / m ² at the start of continuous driving. And it represented with the relative value which sets the light emission lifetime of the organic EL element 145 (comparative example) to 100.

(3) Measurement of polar fluorinated solvent content A sample in which each layer from the hole injection layer to the electron transport layer was formed on a 30 mm square glass substrate in the same manner as the organic EL elements 101 to 145 was prepared. Two samples of about 1 cm mouth were cut out from the flat film portion of this sample. One of them is a part of the whole layer from the hole injection layer to the electron transport layer, which is stripped with a clean wiper soaked in toluene, to make a step, and after sputtering an Ag thin film with SC-701 MkII ECO manufactured by Sanyu Electronics, Veeco The level difference was measured using WYKO manufactured by KK and the film thickness was determined. Further, in the other sample cut out, the entire layer from the hole injection layer to the electron transport layer was removed by immersion in toluene, and the membrane area was determined from the weight ratio before and after the removal. Measure the sample with the area determined above using a temperature-programmed thermal desorption analyzer manufactured by Denshi Kagaku Co., and quantify the desorbed gas component from the mass fragment spectrum corresponding to the polar fluorinated solvent used. The mass ratio of the polar fluorinated solvent per volume of was determined. In addition, the case where a dominant peak is not detected in the mass fragment spectrum corresponding to each polar fluorinated solvent is indicated as “nd” (not detected).

(4) Presence / absence of detection of polar fluorinated solvent in block layer The distribution of polar fluorinated solvent contained in the block layer of each organic EL element was analyzed by TOF-SIMS (time-of-flight secondary ion mass spectrometry), and the layer thickness was analyzed. Fluorine distribution in the direction was measured (measurement was carried out in the form of ions being emitted from the substrate side, and consideration was given so that the component implantation direction at the time of ion collision and the solvent permeation direction at the time of lamination did not coincide). Thereby, when a fluorine atom was detected, it was judged that the polar fluorinated solvent was contained in the block layer.

As shown in Table 2 and Table 3, it can be seen that the organic EL device according to the present invention is superior in luminous efficiency and luminous lifetime as compared with the organic EL device of the comparative example. Moreover, in the manufacturing method of the organic EL element which concerns on this invention, since each component layer is mainly formed using the apply | coating method, it can be applied also to a flexible substrate and it can be said that manufacturing cost can be reduced. .
Therefore, according to the method for manufacturing an organic EL element of the present invention, it can be applied to a flexible substrate, and it can be said that an organic EL element having high light emission efficiency and long life can be manufactured at low cost.

[Example 2]
<< Production of Organic EL Element 201 >>
In the production of the organic EL element 101 of Example 1, the organic EL element 201 was produced in the same manner except that the material contained in the block layer forming coating solution was changed to HS-12.

<< Production of Organic EL Element 202 >>
In the production of the organic EL element 101 of Example 1, the organic EL element 202 was produced in the same manner except that the formation method of the block layer was changed as follows.

(Formation of block layer)
The substrate on which the light emitting layer was formed was attached to a vacuum deposition apparatus without being exposed to the atmosphere. Moreover, what put HS-12 in the molybdenum resistance heating boat was attached to the vacuum evaporation system, and after reducing the vacuum tank to 4 × 10 ⁻⁵ Pa, the boat was energized and heated to heat HS-12 to 0.00. Vapor deposition was performed on the light emitting layer at 1 nm / second to form a block layer having a layer thickness of 10 nm.

<< Evaluation of Organic EL Elements 201 and 202 >>
The organic EL elements 201 and 202 produced as described above were evaluated for light emission efficiency and light emission lifetime in the same manner as in Example 1. The evaluation results are shown in Table 4. In addition, the measurement result of the light emission efficiency and the light emission lifetime in Table 4 was expressed as a relative value where the measurement value of the organic EL element 202 (comparative example) was 100.

As shown in Table 4, it can be seen that the organic EL device according to the present invention is superior in luminous efficiency and luminous lifetime as compared with the organic EL device of the comparative example. This is because the organic EL element 202 of the comparative example has a block layer formed by a vapor deposition method, so that the hydrophobic group of HS-12 does not align with the layer surface (surface on the electron transport layer side), which is an advantageous block. This is probably because the electron transport layer material penetrated into the light emitting layer during the formation of the electron transport layer.
Therefore, according to the method for producing an organic EL element of the present invention, it can be said that it is possible to produce an organic EL element having a higher light emission efficiency and a longer life than when a block layer is formed by vapor deposition.

[Example 3]
<< Production of Organic EL Element 301 >>
In the production of the organic EL element 101 of Example 1, the organic EL element 301 was produced in the same manner except that the material contained in the coating liquid for forming the block layer was changed to HS-2.

<< Preparation of organic EL elements 302 and 303 >>
In the production of the organic EL element 101 of Example 1, the material contained in the block layer forming coating solution was changed as shown in Table 5 and the method for forming the electron transport layer was changed as follows. Similarly, organic EL elements 302 and 303 were produced.

(Formation of electron transport layer)
The substrate on which the block layer was formed was attached to a vacuum deposition apparatus without being exposed to the atmosphere. Moreover, what put compound A in the resistance heating boat made from molybdenum is attached to a vacuum evaporation system, and after reducing the vacuum tank to 4 × 10 ⁻⁵ Pa, the boat is energized and heated to heat compound A to 0.1 nm / The film was deposited on the light emitting layer in seconds to form an electron transport layer having a layer thickness of 30 nm.

<< Evaluation of Organic EL Elements 301-303 >>
The organic EL elements 301 to 303 produced as described above were evaluated for light emission efficiency and light emission lifetime in the same manner as in Example 1. The evaluation results are shown in Table 5. In addition, the measurement result of the luminous efficiency and the light emission lifetime in Table 5 was expressed as a relative value with the measured value of the organic EL element 303 (comparative example) as 100.

  As shown in Table 5, it can be seen that the organic EL device according to the present invention is superior in light emission efficiency and light emission lifetime as compared with the organic EL device of the comparative example. Therefore, according to the method for producing an organic EL device of the present invention, although not as much as when an electron transport layer is formed by a coating method, even when an electron transport layer is formed by a vapor deposition method, high luminous efficiency and long It can be said that a long-life organic EL element can be manufactured.

[Example 4]
<< Production of Organic EL Elements 401 and 402 >>
In the production of the organic EL element 101 of Example 1, the materials contained in the coating liquid for forming the block layer were changed as shown in Table 6 and the method for forming the light emitting layer was changed as follows. Similarly, organic EL elements 401 and 402 were produced.

(Formation of light emitting layer)
The substrate on which the hole transport layer was formed was attached to a vacuum deposition apparatus without being exposed to the atmosphere. Moreover, what put the host compound S-5 in the resistance heating boat made from molybdenum, and what put the phosphorescence dopant D-76 were each attached to the vacuum evaporation system. After depressurizing the vacuum chamber to 4 × 10 ⁻⁵ Pa, the boat was energized and heated to co-deposit the host compound S-5 at 0.01 nm / second and D-76 at 0.09 nm / second, and the layer thickness A 50 nm light emitting layer was formed.

<< Evaluation of Organic EL Elements 401 and 402 >>
The organic EL elements 401 and 402 produced as described above were evaluated for light emission efficiency and light emission lifetime in the same manner as in Example 1. The evaluation results are shown in Table 6. In addition, the measurement result of the luminous efficiency and the light emission lifetime in Table 6 was expressed as a relative value with the measured value of the organic EL element 402 (comparative example) as 100.

  As shown in Table 6, it can be seen that the organic EL device according to the present invention is superior in luminous efficiency and luminous lifetime as compared with the organic EL device of the comparative example. Therefore, according to the method for producing an organic EL element of the present invention, it can be said that an organic EL element having a high luminous efficiency and a long lifetime can be produced even when a light emitting layer is formed by vapor deposition.

  As described above, the present invention can be applied to a flexible substrate, and a method for producing an organic electroluminescence element and an organic electroluminescence capable of producing an organic electroluminescence element with high luminous efficiency and long life at low cost. Suitable for providing an element.

DESCRIPTION OF SYMBOLS 10 Organic EL element 11 Base material 12 Anode 13 Hole injection layer 14 Hole transport layer 15 Light emitting layer 16 Block layer 17 Electron transport layer 18 Electron injection layer 19 Cathode

Claims (12)

A method for producing an organic electroluminescent device comprising a light emitting layer, a block layer, and an electron transport layer between an anode and a cathode,
The said block layer is formed using the coating liquid containing the compound which has a structure represented by following General formula (1), and a polar fluorinated solvent, The manufacturing method of the organic electroluminescent element characterized by the above-mentioned.

[In General Formula (1), X represents O, S or NR ₉ . R ₉ represents a hydrogen atom, a deuterium atom, an alkyl group, an alkenyl group, an alkynyl group, an arylalkyl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, or a non-aromatic heterocyclic ring. Represents a group or a substituent represented by the following general formula (2). R _{1 to} R ₈ are each a hydrogen atom, deuterium atom, halogen atom, cyano group, alkyl group, alkenyl group, alkynyl group, alkoxy group, acyl group, amino group, silyl group, phosphine oxide group, aromatic carbonization This represents a hydrogen ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, a non-aromatic heterocyclic group or a substituent represented by the following general formula (2). At least one of R _{1 to} R ₉ represents a substituent represented by the following general formula (2). R _{1 to} R ₉ may be the same as or different from each other, and may further have a substituent. ]

[In general formula (2), L represents an alkylene group, an alkenylene group, an o-phenylene group, an m-phenylene group, a p-phenylene group, an amide group or a divalent aromatic heterocyclic group, respectively, and further substituted. It may have a group. n represents an integer of 1 to 8. When n represents an integer of 2 or more, L of 2 or more may be the same as or different from each other. R is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a fluorinated alkyl group having 1 to 20 carbon atoms, an aromatic hydrocarbon ring group, an aromatic heterocyclic group or a non-aromatic group. Represents a hydrocarbon ring group, and may further have a substituent. m represents an integer of 1 to 3. At least one of L and R represents an alkylene group or an alkyl group. When there are a plurality of substituents represented by the general formula (2), L and R may be the same or different from each other, but they are not connected to each other to form a ring. ]   The method for producing an organic electroluminescent element according to claim 1, wherein the polar fluorinated solvent is a solvent selected from a fluorinated alcohol, a fluorinated ester, and a fluorinated ether.   The method for producing an organic electroluminescent element according to claim 1, wherein the polar fluorinated solvent contains a fluorinated alcohol having 3 to 5 carbon atoms.   4. The substituent according to claim 1, wherein at least one L of the substituents represented by the general formula (2) is an alkylene group having 1 to 6 carbon atoms. 5. The manufacturing method of the organic electroluminescent element of description.   The substituent represented by the general formula (2) is characterized in that at least one R is an alkyl group having 1 to 6 carbon atoms. The manufacturing method of the organic electroluminescent element of description.   The method for producing an organic electroluminescent element according to claim 1, wherein the electron transport layer is formed using a coating liquid containing an electron transport material.   The method for producing an organic electroluminescence element according to claim 6, wherein the coating liquid containing the electron transport material contains a polar fluorinated solvent.   The said light emitting layer is comprised with the compound whose solubility with respect to a polar fluorinated solvent is lower than the compound which has a structure represented by the said General formula (1), The one of Claim 1-7 The manufacturing method of the organic electroluminescent element of one term.   The method for producing an organic electroluminescent element according to any one of claims 1 to 8, wherein the light emitting layer is composed of a compound having a molecular weight of 3000 or less.   The light-emitting layer contains a compound having a dibenzofuran ring, a dibenzothiophene ring, or a carbazole ring and not having an alkyl group, an alkenyl group, an alkynyl group, or an arylalkyl group. The manufacturing method of the organic electroluminescent element as described in any one of the above. An organic electroluminescence device comprising a light emitting layer, a block layer, and an electron transport layer between an anode and a cathode,
The said block layer contains the compound and polar fluorinated solvent which have a structure represented by following General formula (1), The organic electroluminescent element characterized by the above-mentioned.

[In General Formula (1), X represents O, S or NR ₉ . R ₉ represents a hydrogen atom, a deuterium atom, an alkyl group, an alkenyl group, an alkynyl group, an arylalkyl group, an aromatic hydrocarbon ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, or a non-aromatic heterocyclic ring. Represents a group or a substituent represented by the following general formula (2). R _{1 to} R ₈ are each a hydrogen atom, deuterium atom, halogen atom, cyano group, alkyl group, alkenyl group, alkynyl group, alkoxy group, acyl group, amino group, silyl group, phosphine oxide group, aromatic carbonization This represents a hydrogen ring group, an aromatic heterocyclic group, a non-aromatic hydrocarbon ring group, a non-aromatic heterocyclic group or a substituent represented by the following general formula (2). At least one of R _{1 to} R ₉ represents a substituent represented by the following general formula (2). R _{1 to} R ₉ may be the same as or different from each other, and may further have a substituent. ]

[In general formula (2), L represents an alkylene group, an alkenylene group, an o-phenylene group, an m-phenylene group, a p-phenylene group, an amide group or a divalent aromatic heterocyclic group, respectively, and further substituted. It may have a group. n represents an integer of 1 to 8. When n represents an integer of 2 or more, L of 2 or more may be the same as or different from each other. R is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a fluorinated alkyl group having 1 to 20 carbon atoms, an aromatic hydrocarbon ring group, an aromatic heterocyclic group or a non-aromatic group. Represents a hydrocarbon ring group, and may further have a substituent. m represents an integer of 1 to 3. At least one of L and R represents an alkylene group or an alkyl group. When there are a plurality of substituents represented by the general formula (2), L and R may be the same or different from each other, but they are not connected to each other to form a ring. ]   The organic electroluminescent element according to claim 11, wherein the polar fluorinated solvent is contained in an amount of 1000 ppm by mass or less as a whole of each constituent layer.

Images