JP6549434B2 - Method of manufacturing organic electroluminescent device - Google Patents

Description

The present invention relates to a process for the production of organic electroluminescent devices. In particular, even when the intermediate layer is formed by a wet method, a method of manufacturing a organic electroluminescent device comprising an organic thin film laminate capable of suppressing the lowering function.

  2. Description of the Related Art Conventionally, as a light emitting type electronic display device, an organic electroluminescence (hereinafter, also referred to as “organic EL”) element is mentioned. An organic EL element has a configuration in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and electrons and holes are injected into the light emitting layer to recombine excitons (excitons) by recombination. It is an element that generates light and emits light using emission of light (fluorescence and phosphorescence) when this exciton is inactivated. It can emit light at a voltage of several volts to several tens of volts. Furthermore, it is self-emitting and has a wide viewing angle, high visibility, and is a thin-film type completely solid element, so it is space-saving and portable. It attracts attention from the viewpoint of sex. Furthermore, the organic EL element is also characterized in that it is a surface light source.

  As the attractiveness of organic EL devices as surface light emission and high efficiency light sources increases, the necessity of satisfying all of high efficiency, high luminance and long life is increasing because of their function as commercial products. In response to these requirements, an organic EL device having a multi-unit structure has been reported by a multi-photon emission (MPE) technology in which light emitting units are connected in series by a charge generation layer and stacked in multiple stages (for example, patent Reference 1.).

  The organic EL device using the above-mentioned MPE technology is provided with a plurality of light emitting layers for the purpose of prolonging the life of the device and increasing the luminance, and an intermediate layer is provided between the light emitting layers. As the intermediate layer, for example, a charge generation layer may be provided in which an electron generation layer made of an inorganic semiconductor material having electron injection characteristics and a hole generation layer having hole injection characteristics are stacked. The electron generating layer or the hole generating layer can be formed by co-evaporation or single evaporation.

  Further, in recent years, a technique of forming an intermediate layer by a wet method has been proposed for the purpose of reducing the manufacturing cost of an organic EL element using the MPE technique, and for example, a curable material or an ionic property cured by heat or light A method of forming an intermediate layer by a wet method using a polymer or the like has been proposed (see, for example, Patent Documents 2 and 3).

From paragraph 0290 of Patent Document 2 onward, the necessity of the insolubilization treatment and the method thereof are described. Further, it is disclosed in paragraph 0425 of Patent Document 3 that a material that is difficult to dissolve in the solvent of the upper layer adjacent to the lower layer material is used.
However, the present inventors have found that when the upper layer is formed further than the adjacent layer, the damage due to the penetration of the solvent into the lower layer is a problem. In order to solve the problem, the adjustment of insolubility between two layers disclosed in Patent Document 3 is not sufficient. In addition, in the case of curing treatment of a layer as disclosed in Patent Document 2, the influence of the solvent above the adjacent layer may be reduced, but the heat and light energy used for curing may be reduced. There is a concern that the organic thin film laminate or the base material may be damaged, and the processing apparatus becomes large.

Patent 3933591 gazette Patent No. 5568943 gazette Patent No. 565 3122

  The present invention has been made in view of the above problems and circumstances, and the problem to be solved is an organic thin film laminate capable of suppressing the deterioration of function even when the intermediate layer is formed by a wet method. It is providing a manufacturing method and a manufacturing method of an organic electroluminescent element.

In order to solve the above-mentioned subject concerning the present invention, as a result of examining the cause of the above-mentioned problem etc., it is made to dissolve in polar solvents other than fluorination solvent, and forming organic functional layer using solution of organic functional layer material, Forming at least one intermediate layer of non-hardenable material on the organic functional layer, and forming at least one intermediate layer of the at least one intermediate layer By using a solution in which a conductive polymer having at least a polymerizable group is dissolved in a fluorinated solvent to form any of the intermediate layers, an organic thin film can be obtained even when the intermediate layer is formed by a wet method. It has been found that the functional deterioration of the laminate can be suppressed.
That is, the subject concerning the present invention is solved by the following means.

1 . A method of manufacturing an organic electroluminescent device comprising an organic thin film laminate in which a plurality of organic functional layers made of a non-hardenable material are laminated between an anode and a cathode,
Forming an organic functional layer by dissolving in a polar solvent other than a fluorinated solvent and using a solution of the organic functional layer material;
Forming at least one intermediate layer of non-hardenable material;
Have
In the step of forming the at least one intermediate layer, in forming the intermediate layer of any of the at least one intermediate layer, a solution obtained by dissolving a conductive polymer having at least a polymerizable group in a fluorinated solvent is used. The manufacturing method of the organic electroluminescent element characterized by using.

According to the present invention, it is possible to provide a method of manufacturing an organic thin film laminate and a method of manufacturing an organic electroluminescent device capable of suppressing the functional deterioration even when the intermediate layer is formed by a wet method. it can.
The mechanism for expressing the effects of the present invention or the mechanism of action is not clear but is presumed as follows.
In the fluorinated solvent included in the present invention, the F atom has the highest electronegativity among all the elements and the smallest atomic radius among the halogen elements, so that the polarity of the C—F bond is large. And has a feature that the coupling distance is short and the polarizability is low. The low polarizability of the C—F bond means that the intermolecular force is weak, and the surface free energy is small. As a result, excellent water- and oil-repellency and non-stickiness are generated, and not only the dissolution of the lower layer material is suppressed, but also the deterioration of performance due to aggregation of the dissolved transportable material molecules is suppressed and the permeation to the lower layer is also suppressed. it can. According to the present invention, since the intermediate layer is formed by the coating liquid for forming an intermediate layer containing the conductive polymer not having the above-mentioned polymerizable group and the fluorinated solvent, the conductivity which does not have the polar solvent soluble polymerizable group is obtained. The seemingly incompatible effects of dissolution application of the polymer and suppression of the elution of the lower layer material can be compatible.

Schematic sectional drawing which shows an example of the organic thin film laminated body which concerns on this invention Schematic sectional drawing which shows an example of the organic EL element concerning this invention

The method for manufacturing an organic thin film laminate of the present onset Ming is a manufacturing method of an organic thin film stack in which a plurality of organic functional layer composed of a non-curable materials are laminated, it is dissolved in a polar solvent other than fluoride solvent Forming an organic functional layer using a solution of an organic functional layer material, and forming at least one intermediate layer of a non-hardenable material on the organic functional layer, In the step of forming at least one intermediate layer, a solution in which a conductive polymer having at least a polymerizable group is dissolved in a fluorinated solvent is used to form an intermediate layer of any of the at least one intermediate layers. It is characterized by This feature is or corresponding technical features are common to the following embodiments.
In the present invention, in the step of forming the at least one intermediate layer, the fluorinated solvent used to form any one of the at least one intermediate layers is a C 3-5 fluorinated one. It is preferably an alcohol. By setting the carbon number within the range, it is possible not only to suppress volatilization unevenness and aggregation of solute molecules at the time of drying the coating film, but also to reduce the solvent content in the film so that the effects of the present invention can be maximally exhibited. .
In the present invention, the conductive polymer having no polymerizable group is preferably a polyethyleneimine derivative. By using the material, the charge injection / transport characteristics and the suppression of permeation of the upper layer solvent can be compatible with each other, so that the effects of the present invention can be maximally exhibited.
Further, in the present invention, in the step of forming the at least one intermediate layer, it is preferable to use a metal compound for forming any one of the at least one intermediate layers.
Furthermore, in the present invention, the metal compound is preferably a metal compound containing at least one of an n-type metal oxide and a polyacid. By containing the compound in the intermediate layer, high charge injection and transport characteristics can be obtained, and the effects of the present invention can be exhibited to the maximum.
Moreover, in the present invention, the metal compound is preferably contained as fine particles containing a metal compound. By using the fine particles, it is possible to form a metal compound layer by a wet method, and since a process such as annealing is not necessary, the manufacturing cost can be reduced.
In the present invention, the metal compound is preferably selected from fine particles containing ZnO, TiO ₂ , ZrO or aluminum-doped zinc oxide (AZO). By using the fine particles, high charge injection transport characteristics and visible light transmittance can be obtained, so that the effects of the present invention can be maximized.
The method for producing an organic electroluminescent device according to the present invention is a method for producing an organic electroluminescent device comprising an organic thin film laminate in which a plurality of organic functional layers made of a non-hardenable material are laminated between an anode and a cathode. Forming an organic functional layer using a solution of an organic functional layer material by dissolving it in a polar solvent other than a fluorinated solvent, and forming an intermediate layer of at least one layer made of a non-hardenable material; In the step of forming the at least one intermediate layer, a conductive polymer having at least a polymerizable group is dissolved in a fluorinated solvent in forming the intermediate layer of any of the at least one intermediate layers. It is characterized in that the solution is used.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In the present application, “to” is used in the meaning including the numerical values described before and after that as the lower limit value and the upper limit value.

<< Overview of Organic Thin Film Laminates >>
Hereinafter, specific embodiments of the organic thin film laminate according to the present invention will be described.
The organic thin film laminate according to the present invention is configured by laminating a plurality of organic functional layers made of a non-hardenable material, and is an organic functional that is soluble in polar solvents other than fluorinated solvents and insoluble in fluorinated solvents. An organic functional layer containing a layer material, and at least one intermediate layer provided on the organic functional layer and made of a non-hardenable material, and the like, and among the at least one intermediate layer For forming any of the intermediate layers, a solution in which a conductive polymer having at least a polymerizable group is dissolved in a fluorinated solvent is used.

Here, in the present invention, the non-hardenable material refers to a material composed of a compound which does not contain a polymerizable group in its molecular or crystal structure. Therefore, the organic functional layer according to the present invention does not contain a compound containing a polymerizable group, such as a photocurable compound or a thermosetting compound.
In addition, as the polymerizable group, for example, cyclic ethers having a carbon-carbon unsaturated group such as a vinyl group, an acryl group, a methacryl group, an acrylamido group or an allyl group, an epoxy group, an oxetane group, etc., tetrahydrothiophene And cyclic sulfides and isocyanate groups.

<Organic functional layer>
Examples of the organic functional layer of the present invention include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a light emitting layer, a hole blocking layer and the like used in an organic electroluminescent device.
Hereinafter, an organic thin film laminate in which an intermediate layer is formed on the first light emitting layer as the organic functional layer will be described as an example. Such an organic thin film laminate is suitably used for a multiphoton type organic EL element or the like.

The structure of the organic thin film laminated body 10 of this embodiment is shown in FIG.
An organic thin film laminate 10 shown in FIG. 1 includes a base 11, a first light emitting layer (organic functional layer) 12, an intermediate layer 13, and a second light emitting layer (organic functional layer) 14. Specifically, the first light emitting layer 12 is formed on the base material 11, and the intermediate layer 13 is provided on the first light emitting layer 12. Furthermore, a second light emitting layer 14 is provided on the intermediate layer 13. The first light emitting layer 12 and the second light emitting layer 14 are configured of at least one layer or more.
Hereinafter, each configuration of the organic thin film laminate 10 will be described.

"Base material"
There is no limitation in particular in the material of the base material 11 used for the organic thin film laminated body 10, 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 thin film laminate 10.

  Examples of resin films include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate (TAC), cellulose acetate butyrate, and cellulose acetate propionate (for example, CAP), cellulose acetate phthalate, cellulose esters such as 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 polyetherimide, polyetherketoneimide, polyamide, fluorocarbon resin, nylon, polymethyl methacrylate, acrylic or polyarylates, Artone (trade name, manufactured by JSR Corporation) or Appel (trade name, manufactured by Mitsui Chemicals, Inc.) Films such as resins can be mentioned.

On the surface of the resin film, a gas barrier film may be formed by a coating of an inorganic substance or an organic substance or a hybrid coating of both of them. The gas barrier film has a water vapor transmission rate (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) of 0.01 g / (m ² · 24 h) measured by the method according to JIS K 7129-1992. The following gas barrier films are preferred. Furthermore, the oxygen permeability measured by the 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 / It is preferable that it is a high gas barrier film (m ² · 24 h) or less.

  As a material for forming the gas barrier film, any material having a function of suppressing the entry of moisture, oxygen and 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 the inorganic layer and the layer made of an organic material. Although there is no restriction | limiting in particular about the order of lamination | stacking of an inorganic layer and an organic layer, It is preferable to laminate | stack both in multiple times alternately.

  There is no particular limitation on the method of forming the gas barrier film, and, for example, vacuum evaporation, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma treatment A legal method, plasma CVD method, laser CVD method, thermal CVD method, coating method, etc. can be used. For example, what is based on the atmospheric pressure plasma polymerization method which is described in Unexamined-Japanese-Patent No. 2004-68143 is preferable.

<< organic functional layer = first light emitting layer >>
The first light emitting layer 12 according to the present invention contains a first light emitting layer material which is soluble in polar solvents other than fluorinated solvents and insoluble in fluorinated solvents.

  The first light emitting layer 12 is a layer that provides recombination of electrons and holes injected from an electrode or an adjacent layer, and provides a field of light emission via an exciton. The first light emitting layer 12 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 materials for the first light emitting layer such as the light emitting dopant and the host compound constituting the first light emitting layer, materials which are soluble in polar solvents other than the fluorinated solvent and insoluble in the fluorinated solvent are used. All the materials described in this condition satisfy this condition. Many of the conventionally known light emitting layer materials are insoluble in fluorinated solvents.
Here, the solvent solubility which is the judgment of the solubility and insolubility of the first light emitting layer material can be determined from the rinse-out amount test at 30 ° C. of the thin film of the material.
Specifically, after forming a coating composition containing the material on a 30 mm square quartz substrate and drying it, 0.2 mL of only the solvent whose solubility is to be confirmed is dropped on the dried film, and 500 rpm for 30 seconds. The soluble component can be rinsed out by spin coating under the conditions. In the present invention, the UV-visible spectral intensity ratio (post-rinsing intensity / pre-rinse intensity) before and after rinsing is measured, and the intensity ratio (%) at the maximum absorption peak or shoulder in the wavelength range of 200 nm to 600 nm is subtracted from 100%. When the amount of rinse-out is 5% or less, it is insoluble, and when it is 5% or more, it is soluble.

<Polar solvents other than fluorinated solvents>
The polar solvent other than the fluorinated solvent as referred to in the present invention means a hydrophilic solvent having a relative dielectric constant of 3 or more and a water solubility of 5 g / L or more at 25 ° C. Specifically, non-fluorinated alcohols such as methanol, ethanol, methoxyethanol, ethoxyethanol, propanol, butanol, pentanol, cyclohexanol, ethylene glycol, phenol etc., methyl acetate, ethyl acetate, propyl acetate, acetic acid Fluorine-free esters such as butyl, fluorine-free nitriles such as acetonitrile, propionitrile and benzonitrile, fluorine-free ketones such as acetone, butanone and cyclohexanone, dimethyl ether, diethyl ether, methyl ethyl ether, Dipropyl ether etc. Ethers containing no fluorine and the like.

  The method for forming the first light emitting layer 12 is not particularly limited, and can be formed by, for example, a conventionally known vacuum evaporation method or wet method. Among them, in terms of reducing the manufacturing cost of the organic thin film laminate 10, it is preferable to form by a wet method.

  As a wet method, for example, a spin coat method, a cast method, an ink jet method, a printing method, a die coat method, a blade coat method, a roll coat method, a spray coat method, a curtain coat method, an LB method (Langmuir-Blodgett method) etc. It can be used. Among them, a method applicable to a roll-to-roll system such as a die coating method, a roll coating method, an inkjet method, a spray coating method is preferable from the viewpoint of obtaining a homogeneous thin film easily and high productivity.

As a liquid medium for dissolving or dispersing the first light emitting layer material in the wet method, for example, ketones such as methyl ethyl ketone and cyclohexanone, fatty acid esters such as ethyl acetate, halogenated hydrocarbons such as dichlorobenzene, toluene and xylene Aromatic hydrocarbons such as mesitylene and cyclohexylbenzene, aliphatic hydrocarbons such as cyclohexane, decalin and dodecane, and organic solvents such as dimethylformamide (DMF) and dimethylsulfoxide (DMSO) can be used.
When the first light emitting layer material is dispersed in the liquid medium, it can be dispersed by, for example, a dispersion method such as ultrasonic wave, high shear force dispersion, or media dispersion.

When a vapor deposition method is employed as a method of forming the first light emitting layer 12, the vapor deposition conditions vary depending on the type of compound used, etc., but generally the boat heating temperature is 50 to 450 ° C. and the vacuum degree is 10 ^-6 to 10 ^-2 It is desirable to appropriately select Pa, a deposition rate of 0.01 to 50 nm / sec, 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 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 particular dopant used and the requirements of the device. The concentration of the light emitting dopant may be contained in a uniform concentration in the layer thickness direction of the light emitting layer, or may have an arbitrary concentration distribution.

  In addition, the first light emitting layer 12 may contain a plurality of light emitting dopants. For example, a combination of dopants having different structures, or a combination of a fluorescent dopant and a phosphorescent dopant may be used. Thereby, arbitrary luminescent color can be obtained.

In the organic thin film laminate 10, it is preferable that one or more light emitting layers contain a plurality of light emitting dopants having different luminescent colors, and the whole organic thin film laminate 10 exhibits white light emission. There are no particular limitations on the combination of light emitting dopants that exhibit white, but examples include combinations of blue and orange, combinations of blue, green, and red, and the like. As white color in the organic thin film laminate 10, 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 by the above-mentioned method. It is preferable to be in the range of y = 0.38 ± 0.08.

[1-1. Phosphorescent Luminescent Dopant]
The phosphorescent dopant is a compound in which light emission from an excitation triplet is observed, and specifically, a compound which phosphoresces at room temperature (25 ° C.), and the phosphorescence quantum yield is 0 at 25 ° C. .01 or more compounds. Among the phosphorescent dopants used in the light emitting layer, a preferable phosphorescent quantum yield is 0.1 or more.

  The above-mentioned phosphorescence quantum yield can be measured by the method described on page 398 (1992 edition, Maruzen) of Spectrum II of Fourth Experimental Chemistry Course 7. The phosphorescence quantum yield in solution can be measured using various solvents. The phosphorescence emitting dopant used in the light emitting layer may achieve the phosphorescence quantum yield (0.01 or more) in any of the solvents.

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

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

[1-2. Fluorescent dopant]
The fluorescent dopant is a compound capable of emitting light from an excitation singlet, and is not particularly limited as long as emission from the excitation singlet is observed.

  The fluorescent dopant is, for example, anthracene derivative, pyrene derivative, chrysene derivative, fluoranthene derivative, perylene derivative, fluorene derivative, arylacetylene derivative, styrylarylene derivative, styrylamine derivative, arylamine derivative, boron complex, coumarin derivative, Pyrane derivatives, cyanine derivatives, croconium derivatives, squalium derivatives, oxobenzanthracene derivatives, fluorescein derivatives, rhodamine derivatives, pyrilium derivatives, perylene derivatives, polythiophene derivatives, rare earth complex compounds, and the like.

Further, as a fluorescent dopant, a luminescent dopant using delayed fluorescence may be used.
As a specific example of the light emission dopant using delayed fluorescence, the compound as described in international publication 2011/156793, Unexamined-Japanese-Patent No. 2011-213643, Unexamined-Japanese-Patent No. 2010-93181 etc. is mentioned, for example.

[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 device.
Preferably, the phosphorescence quantum yield of phosphorescence emission at room temperature (25 ° C.) is a compound of less than 0.1, and more preferably, the compound of which phosphorescence quantum yield is 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.

The excited state energy of the host compound is preferably higher than the excited state energy of the light emitting dopant contained in the same layer.
The host compounds may be used alone or in combination of two or more. By using a plurality of host compounds, charge transfer can be adjusted, and the efficiency of the organic EL element can be improved.

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

  The molecular weight of the light emitting dopant and host compound used in the first light emitting layer is not particularly limited. Here, according to the present invention, since the intermediate layer can suppress the permeation of the solvent, the solvent of the layer (such as the second light emitting layer) formed by coating on one side of both surfaces of the intermediate layer is the intermediate layer It is effectively suppressed that the layer (the first light emitting layer or the like) formed on the other side of the two surfaces is reached and dissolved. For this reason, the light-emitting dopant and host compound contained in the first light-emitting layer is, for example, a low molecular weight material having a molecular weight of 3,000 or less, and thus the organic substance according to the present invention is soluble in polar solvents other than fluorinated solvents. It can be applied to thin film laminates.

As a known host compound, while having a hole transporting ability or an electron transporting ability, long wavelength emission can be prevented, and further, from the viewpoint of stability against heat generation when the organic EL device is driven at high temperature or during device actuation, It is preferred to have a high glass transition temperature (Tg). As a host compound, it is preferable that Tg is 90 degreeC or more, More preferably, it is 120 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).

<< 2nd organic functional layer = 2nd light emitting layer >>
The second light emitting layer 14 is a layer stacked on the first light emitting layer 12 with the intermediate layer 13 interposed therebetween.
As described above, according to the present invention, since the intermediate layer made of the non-curable material contains a conductive polymer having no polymerizable group, the coating liquid for forming the second light emitting layer is formed on the intermediate layer by a wet method. Even when the second light emitting layer 14 is formed by coating, the penetration of the solvent contained in the coating liquid for forming the second light emitting layer into the first light emitting layer 12 can be effectively suppressed.

The second light emitting layer 14 contains a second light emitting layer material, and the same material as the first light emitting layer material can be used as the second light emitting layer material.
Further, as a method of forming the second light emitting layer, the same method as the method of forming the first light emitting layer can be used.

Middle layer
The middle layer 13 is a layer made of a non-curable material, and contains a conductive polymer having no polymerizable group.

  The intermediate layer 13 can be formed by applying a coating liquid for forming an intermediate layer containing a conductive polymer having no polymerizable group and a fluorinated solvent. Thus, when the second light emitting layer 14 is formed by applying the second light emitting layer forming coating solution containing the second light emitting layer material, the solvent contained in the second light emitting layer forming coating solution is Permeation to the first light emitting layer 12 which is a lower layer of the intermediate layer 13 can be suppressed. Therefore, the solvent used for the formation of the second light emitting layer 14 can suppress the dissolution of the first light emitting layer 12, the roughening of the surface, the crystallization of the material of the first light emitting layer, and the like. Performance reduction can be suppressed. In addition, since the first light emitting layer material constituting the first light emitting layer 12 is insoluble in the fluorinated solvent, even if the fluorinated solvent contained in the coating solution for forming the intermediate layer contacts the first light emitting layer 12, Dissolution of the first light emitting layer 12 can be suppressed.

  Here, in the present invention, the underlying layer of the intermediate layer, which is already formed before the intermediate layer is formed, is referred to as the lower layer, and the layer formed on the intermediate layer after the intermediate layer is formed is It is called the upper layer.

  In addition, by using the coating solution for forming an intermediate layer as a liquid composition containing the above-described fluorinated solvent, a conductive polymer having no polymerizable group capable of blocking solvent permeation as described above, which was difficult until now. And the reduction of the influence on the lower layer of the fluorinated solvent contained in itself. As a result, there is no need to add an intermediate layer curing treatment step such as high temperature annealing or UV irradiation which distorts a resin substrate or the like, and the organic thin film laminate can be manufactured inexpensively and stably.

  The wet method for forming the intermediate layer 13 according to the present invention includes, for example, spray coating, electro spray coating, inkjet, mist CVD, gravure coating, bar coating, bar coating, roll coating, dip coating, screen printing, flexographic printing, offset printing, etc. Can be mentioned. In addition, these wet methods also include the case where the liquid composition in which the intermediate layer material is dissolved or dispersed in the liquid medium is such that the solvent is dried before reaching the lower layer. In addition, when forming the intermediate | middle layer 13 which concerns on this invention by a wet method, you may carry out on any conditions under air | atmosphere or inert gas atmosphere.

  The intermediate layer 13 may be provided in a plurality of layers. Further, the intermediate layer 13 can be a layer having a function of supplying electrons to the adjacent layer on the anode side and holes to the adjacent layer on the cathode side. For example, a charge generation layer can be formed by combining a hole generation layer that generates holes and an electron generation layer that generates electrons. Furthermore, the intermediate layer 13 can be formed of, for example, an intermediate electrode, an intermediate conductive layer, a charge generation layer, an electron extraction layer, a connection layer, an intermediate insulating layer, or the like.

  Thus, when the intermediate layer 13 is provided in a plurality of layers, at least one of them is formed by a wet method using a conductive polymer having no polymerizable group and a fluorinated solvent, and another intermediate layer There is no limitation on the method of production. Further, the order of lamination of the intermediate layer formed by the wet method and the intermediate layer formed by the other manufacturing method is not particularly limited. The lamination order of the intermediate layer formed by the wet method and the intermediate layer formed by the other manufacturing method is not particularly limited, but the intermediate layer laminated adjacent to the first light emitting layer is a layer formed by the wet method Is preferred.

  As the above-mentioned other production method, any method may be used, for example, the above-mentioned wet method, vapor deposition method, atomic layer deposition (ALD), sputtering method etc. may be mentioned, but the wet method or ALD method Is preferred. According to the wet method, the manufacturing cost can be reduced, and in particular, according to the wet method using a fluorinated solvent, the functional deterioration of the organic thin film laminate can be more reliably suppressed. In addition, since the ALD method can form a thin layer without defects, even when the second light emitting layer is stacked on the intermediate layer using the wet method, the intermediate layer formed by the ALD method is used. Thus, damage to the first light emitting layer by the solvent of the second light emitting layer can be suppressed.

  The thickness of the intermediate layer 13 is preferably in the range of 1 to 100 nm, and more preferably in the range of 5 to 50 nm. When middle class 13 is constituted by two or more layers, it is preferred that the total layer thickness is within the limits concerned. When the layer thickness of the intermediate layer 13 is 1 nm or more, not only the function as the charge generation layer can be effectively exhibited, but also the penetration of the solvent contained in the coating liquid forming the upper layer can be suppressed more reliably. can get. In addition, when the layer thickness of the intermediate layer 13 is 50 nm or less, sufficient charge transportability of the intermediate layer 13 can be ensured, and absorption and scattering of emitted light are suppressed to obtain high emission efficiency as the whole organic thin film laminate. Can.

[Conductive polymer having no polymerizable group]
The intermediate layer according to the present invention contains a conductive polymer having no polymerizable group. The conductivity refers to one having a volume resistivity of 10 ⁸ Ω · cm or less (23 ° C., 50% RH).
The conductive polymer having no polymerizable group contained in the intermediate layer according to the present invention is not particularly limited as long as it is a material having a weight average molecular weight of 2000 or more, but the weight average molecular weight is 10000 or more and 1,000,000 or less from the viewpoint of suppressing solvent permeation. Is preferred. Moreover, it is preferable that it is a conductive polymer containing a polar group and an ionic group from a viewpoint of charge injection transport. For example, polyethyleneimine, polyethyleneimine alkoxide, polyethyleneimine isocyanate, polyethyleneimine derivative such as polyethyleneimine alkylene oxide, polycarbazole derivative, polyvinylpyridine derivative, polyethylene oxide derivative, poly (n-vinylcarbazole) derivative, polyfluorene derivative, polyphenylene and the like Derivatives thereof, poly (p-phenylene vinylene) and derivatives thereof, polythiophene and derivatives thereof, poly (pyridine vinylene) and derivatives thereof, polyquinoxaline and derivatives thereof, polyquinoline and derivatives thereof, polyoxadiazole derivatives, polybathophenanthroline derivatives, Polytriazole derivatives as well as polysilane derivatives are mentioned, as appropriate, and amine groups, hydroxy groups, nitrile groups, cal Polar group such as sulfonyl group, and, carbocation, an ammonium cation, phosphonyl cation, sulfonyl cation, iodonium cation or metal cation and ^{F -, Cl -, Br -} , I -, OH -, RbSO 3 -, RbCOO - , ClO ⁻ , ClO ₂ ⁻ , ClO ₃ ⁻ , ClO ₄ ⁻ , SCN ⁻ , CN ⁻ , CN ₃ ⁻ , NO ₄ ⁻ , SO ₄ ²⁻ , HSO ₄ ⁻ , PO ₄ ³⁻ , HPO ₄ ²⁻ , H ₂ PO ₄ ⁻ And BF ₄ ⁻ or PF ₆ ⁻ or the like.
The weight average molecular weight was measured by gel permeation chromatography (GPC: Gel Permeation Chromatography) using polystyrene as a standard.

[Fluorinated solvent]
The fluorinated solvent is contained in an amount of 1 mass ppm or more in the organic thin film laminate according to the present invention.
In fluorinated solvents, since the F atom has the highest electronegativity of all elements and the smallest atomic radius of halogen elements, the bond distance is short although the polarity of the C—F bond is large. Therefore, the polarizability is low. In addition to dissolving materials soluble in some polar solvents and enabling wet film formation, it is also possible to use solvents that are not fluorinated with the same molecular skeleton, even if the lower layer is a layer soluble in polar solvents. In contrast, elution of the lower layer material can be suppressed by using a solvent containing a fluorinated solvent having a low polarizability. In addition, the fact that the polarizability of the C—F bond is low means that the intermolecular force is weak, resulting in the feature that the surface free energy is small. As a result, excellent water- and oil-repellency and non-stickiness are generated, and not only the dissolution of the lower layer material is suppressed, but also the deterioration of performance due to aggregation of the dissolved transportable material molecules is suppressed and the permeation to the lower layer is also suppressed. it can.
The content of the fluorinated solvent in the organic thin film laminate is preferably 1000 mass ppm or less. By setting it in this range, the molecules in the organic thin film laminate are not reoriented to be crystal grains but the charges in the crystal grain boundaries without energy loss such as heat generated at the time of driving without impairing charge exchange between transport material molecules. There is no reduction in transportability due to the trap.

  The boiling point of the fluorinated solvent is preferably in the range of 50 to 200 ° C., below which the unevenness due to heat of vaporization at the time of volatilization tends to occur, and above this drying of the solvent is delayed and the solvent content in the film increases. Therefore, there are problems such as promoting the crystal growth in the film and the roughening path of the solvent, so that the density is lowered and the current efficiency is lowered. More preferably, it is in the range of 70 to 150 ° C.

  The water content of the fluorinated solvent is preferably as small as possible because it becomes a quencher of light emission even if it is a very small amount, preferably 100 ppm or less, and more preferably 20 ppm or less.

As the fluorinated solvent, polar solvents are preferable, and fluorinated alcohol, fluorinated acrylate, fluorinated methacrylate, fluorinated ester, fluorinated ether, fluorinated hydroxyalkylbenzene are preferable, and from the viewpoint of solubility and drying property, fluorinated alcohol is preferable. More preferable.
The carbon number of the fluorinated alcohol is not particularly limited, but is preferably 3 to 5 carbon atoms from the viewpoint of the solvent boiling point and the solubility.

  As the fluorine substitution position, for example, in the case of alcohol, the position of hydrogen may be mentioned, and as the fluorination ratio, it may be fluorinated so as not to lose the solubility of the material, and fluorinated to such an extent that the lower layer material is not eluted. It is desirable that it is done.

  Specific examples of fluorinated alcohol include, for example, 1H, 1H-pentafluoropropanol, 6- (perfluoroethyl) hexanol, 1H, 1H-heptafluorobutanol, 2- (perfluorobutyl) ethanol, 3- (3 Perfluorobutyl) 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-octaful Ropentanol (OFAO), 1H, 1H, 7H-dodecafluoropentanol, 2H-hexafluoro-2-propanol, 1H, 1H, 3H-hexafluorobutanol (HFBO), 2,2,3,3,4,4, Examples include 5,5-octafluoro-1,6-hexanediol, 2,2-bis (trifluoromethyl) propanol and the like, but TFPO, OFAO and HFBO are preferable from the viewpoint of the above-mentioned boiling point and solubility.

The fluorinated solvent may be contained in the organic thin film laminate in an amount of 1 mass ppm or more, and the fluorinated solvent does not have to be 100% by mass as a solvent composition contained in the coating solution for forming an intermediate layer.
The solvent contained in the coating solution for forming an intermediate layer may be a mixed solvent of two or more fluorinated solvents, as long as it does not dissolve the first light emitting layer material, or a fluorinated solvent and a fluorinated solvent. A mixed solvent of other solvents may be used, and, for example, a mixed solvent of alcohol and fluorinated alcohol can be used. In the case of the mixed solvent, the content of the fluorinated solvent is preferably 50% by mass or more and 100% by mass.

  The content of the fluorinated solvent in the organic thin film laminate can be measured by temperature-programmed desorption mass spectrometry described in Example 1 described later.

[Other interlayer materials]
(Metal compounds)
As other intermediate layer materials contained in the intermediate layer, for example, metal compounds such as metals, metal oxides, metal nitrides, metal sulfides, polyacids or inorganic salts are preferable, and metal compounds are more preferable. More preferably, the metal compound contains either or both of an n-type metal oxide and a polyacid.

(N-type metal oxide)
The n-type metal compound is not particularly limited, and examples thereof include oxides such as zinc, aluminum, zirconium, yttrium, hafnium, titanium, copper, tungsten, vanadium and molybdenum, and complex oxides such as ITO, AZO and YSZ. Be From the viewpoint of physical properties such as work function and ionization potential, the metal compound is at least selected from ZnO, ZrO, Y ₂ O ₃ , AZO, YSZ, WO ₃ , TiO ₂ , CuO, MoO ₃ , V ₂ O ₅ It is preferable to include one.

(Poly acid)
Examples of polyacids (also referred to as heteropolyanions or polyoxymetallates) include polyacids containing transition metals such as zinc, aluminum, zirconium, yttrium, hafnium, titanium, copper, tungsten, vanadium, molybdenum, etc. Either an isopolyacid consisting of a single transition metal or a heteropolyacid consisting of a plurality of oxo acids can be used, and is preferably a heteropolyacid. The heteropoly acids include phosphomolybdic acid _{(H 3 [PMo 12 O 40} ]), silicomolybdic acid _{(H 4 [SiMo 12 O 40} ]), phosphotungstic acid _{(H 3 [PW 12 O 40} ] And silicotungstic acid (H ₃ [SiW ₁₂ O ₄₀ ]) and lintungstomolybdic acid (H ₃ [PW ₆ Mo ₆ O ₄₀ ]).

  These materials may be contained in the same layer together with the conductive polymer not having the above-mentioned polymerizable group, and the intermediate layer is composed of a plurality of layers, and a layer containing the above-mentioned conductive polymer among those layers. And may be contained in another layer.

  Further, as the other intermediate layer material contained in the intermediate layer, a material which can form a film by a wet method or an ALD method containing a fluorinated solvent among the above materials is preferable, for example, J. Appl. Phys. 97, 121301 Any material may be used without particular limitation as long as it is a material described in (2005) [Surface chemistry of atomic layer deposition: A case study for the trimethylaluminum / water process].

When the intermediate layer is composed of a plurality of layers, examples of the plurality of layers other than the layer containing the conductive polymer having no polymerizable group include, for example, ITO (indium tin oxide), IZO Indium zinc oxide), ZnO, ZrO, Y ₂ O ₃ , ZrN, HfN, TiO _x , VO _x , WO x, MoO x, NiO x, AZO (aluminum-doped zinc oxide), YSZ (yttria stabilized zirconia), CuI, Conductive inorganic compound layers such as InN, GaN, CuAlO ₂ , CuGaO ₂ , SrCu ₂ O ₂ , LaB ₆ , RuO ₂ , Al, Ag, etc., bilayer films such as Au / Bi ₂ O ₃ , SnO ₂ / Ag _{/ SnO 2, ZnO / Ag /} ZnO, Bi 2 O 3 / Au / Bi 2 O 3, TiO 2 / TiN / TiO 2, TiO 2 / ZrN / T O ₂ or the like multilayer film, The conductive organic material layer such as fullerenes or oligothiophene of C60 and the like, metal phthalocyanines, metal free phthalocyanines, metal porphyrins or metal-free porphyrins conductive organic compound layer such as the like Examples include, but are not limited to.

[Preferred Example of Intermediate Layer]
As a structure of the intermediate | middle layer which concerns on this invention, it is preferable to be comprised by multiple layers as mentioned above. In particular, a first intermediate layer is laminated on the first light emitting layer, a second intermediate layer containing the conductive polymer laminated on the first intermediate layer and having no polymerizable group, It is preferable to be comprised by the 3rd intermediate | middle layer laminated | stacked on the said 2nd intermediate | middle layer.
The first intermediate layer, the second intermediate layer, and the third intermediate layer are preferably laminated in this order from the first light emitting layer side, but the order of lamination may be any. In addition, as long as the second intermediate layer containing the conductive polymer having no polymerizable group is provided, one of the first intermediate layer and the third intermediate layer may not be provided. Both the intermediate layer and the third intermediate layer may not be provided.

The first intermediate layer is a layer laminated adjacent to the first light emitting layer and containing a metal compound.
The metal compound contained in the first intermediate layer is not particularly limited, but is preferably an n-type metal oxide, for example, oxides such as zinc, aluminum, zirconium, yttrium, hafnium, titanium, copper, tungsten, vanadium, molybdenum and the like And complex oxides such as ITO, AZO and YSZ. From the viewpoint of physical properties such as work function and ionization potential, the metal compound is at least selected from ZnO, ZrO, Y ₂ O ₃ , AZO, YSZ, WO ₃ , TiO ₂ , CuO, MoO ₃ , V ₂ O ₅ It is preferable to include one.

  As the metal compound, it is preferable to use nanoparticles or metal alkoxides from the viewpoint of enabling application by a wet method, and it is more preferable to use nanoparticles because a process such as annealing is not necessary. When nanoparticles of metal compounds are used, the particle size and shape are not particularly limited, and for example, particles of various shapes such as spheres, rods, flats, wires and the like can be used. Moreover, as these nanoparticles, it is also possible to use surface-modified ones, and it is possible to use, for example, core-shell type particles coated with organic ligands or different metal compounds.

  The layer thickness of the first intermediate layer is not particularly limited and is appropriately set depending on the material constituting the first intermediate layer, but can be, for example, in the range of 10 to 15 nm.

  The second intermediate layer is a layer laminated adjacently to the first intermediate layer and containing a conductive polymer having no polymerizable group.

  The layer thickness of the second intermediate layer is not particularly limited and is appropriately set depending on the material constituting the second intermediate layer, but can be, for example, in the range of 15 to 20 nm.

The third intermediate layer is a layer laminated adjacent to the second intermediate layer and containing a metal compound.
The metal compound contained in the third intermediate layer is not particularly limited, but is preferably a polyacid (also referred to as heteropolyanion or polyoxymetallate), and examples thereof include zinc, aluminum, zirconium, yttrium, hafnium, titanium, copper, Examples include polyacids containing transition metals such as tungsten, vanadium and molybdenum. Either an isopolyacid consisting of a single transition metal or a heteropolyacid consisting of a plurality of oxo acids can be used, and is preferably a heteropolyacid. The heteropoly acids include phosphomolybdic acid _{(H 3 [PMo 12 O 40} ]), silicomolybdic acid _{(H 4 [SiMo 12 O 40} ]), phosphotungstic acid _{(H 3 [PW 12 O 40} ] Preferably, any one of silicotungstic acid (H ₃ [SiW ₁₂ O ₄₀ ]) and lintungstomolybdic acid (H ₃ [PW ₆ Mo ₆ O ₄₀ ]) is contained.

  The layer thickness of the third intermediate layer is not particularly limited and may be appropriately set depending on the material constituting the third intermediate layer, but may be, for example, about 10 nm.

The second intermediate layer preferably further contains the following organic polymer binder as a polymer binder, and the first intermediate layer and the third intermediate layer do not have the above-described polymerizable group as a polymer binder and / or a conductive polymer It is preferable to contain the following organic polymer binder.
In the case where the first to third intermediate layers are formed by a wet method, a stable layer in which the above metal compound is uniformly dispersed by adding a polymer binder to the first to third intermediate layer forming coating solutions. Can be formed with an appropriate layer thickness. Thereby, high efficiency of the organic thin film stack can be achieved.

The organic polymer binder is preferably soluble in the solvent contained in each intermediate layer forming coating solution, and specifically, for example, polystyrene, polyvinyl alcohol, polyvinyl pyridine, polyvinyl phenol and the like can be used. . Among these, poly (4-vinylpyridine) generally used as a surfactant, an adhesive or the like is preferable.
When poly (4-vinylpyridine) is used, the weight average molecular weight is 10,000 to 100,000 in terms of the solubility in the solvent contained in the coating solution for forming each intermediate layer, the dispersibility of the metal compound, and the film forming property. It is preferable to be of the order.
In addition, for example, poly (2-vinylpyridine) or polyethylene oxide can also be suitably used in terms of the effect of improving the electron injection property.

The addition amount of the organic polymer binder, when contained in the first or third intermediate layer, is sufficient within the range capable of improving the dispersibility of the above-mentioned metal compound and the film forming property, and It is preferable to set it in the range of -30 mass%.
When the second intermediate layer is a mixed layer of a conductive polymer and an organic polymer binder, the amount of the organic polymer binder added is sufficient as long as the film formability and the fastness can be improved. It is preferable to make it in the range of 2.5-25 mass% with respect to it.

<< The effect of the organic thin film layered product concerning the present invention >>
In the organic thin film laminate according to the present invention, the upper layer is formed by using the conductive polymer having no polymerizable group and the fluorinated solvent to form an intermediate layer capable of blocking permeation of the upper layer solvent into the lower layer. When (the second light emitting layer side) is formed by a wet method, damage to the lower layer (the first light emitting layer side) due to the solvent can be reduced. In addition, since the intermediate layer material is a non-hardenable material, it does not require a curing process such as a high temperature process for curing the curable material, and the organic thin film laminate is formed on a resin base using a wet method. It can be made.

  The organic thin film laminate may have another layer between the first light emitting layer and the intermediate layer, or may have another layer between the intermediate layer and the second light emitting layer. .

  Although the organic thin film layered product concerning the present invention can be used preferably as composition of an organic EL element mentioned below, it is applicable also to organic devices other than an organic EL element. As such an organic device, an organic light emitting diode, an organic thin-film transistor, an organic solar cell etc. are mentioned, for example.

<< Method of manufacturing organic thin film laminate >>
The method for producing an organic thin film laminate according to the present invention is a method for producing an organic thin film laminate in which a plurality of organic functional layers made of a non-curable material are laminated, and is dissolved in a polar solvent other than a fluorinated solvent Forming an organic functional layer using a solution of functional layer material, and forming an intermediate layer of at least one layer of non-hardenable material on the organic functional layer; In the step of forming the intermediate layer of the layers, a solution obtained by dissolving a conductive polymer having at least a polymerizable group in a fluorinated solvent is used to form an intermediate layer of any of the at least one intermediate layer. It features.

  Since the organic thin film laminate to be produced is the same as the configuration shown in FIG. 1, in the following description, the reference numerals used in FIG. 1 are used and the detailed description of each configuration is omitted.

  First, the first light emitting layer 12 is formed on the substrate 11. As described above, the first light emitting layer 12 may be formed by a wet method (wet process) or a vapor deposition method (dry process), but from the viewpoint of reducing the manufacturing cost of the organic thin film laminate 10, the wet method is used. It is preferable to form.

Next, an intermediate layer 13 is formed on the first light emitting layer 12 using a non-curable material and a fluorinated solvent. The non-curable material used herein contains a conductive polymer having no polymerizable group.
When the intermediate layer 13 has a single-layer structure, it is preferable to form the intermediate layer 13 by a wet method using a coating solution for forming an intermediate layer containing a non-curable material and a fluorinated solvent. Moreover, when the intermediate layer 13 is comprised by multiple layers, the coating liquid for 1st intermediate layer formation containing a metal compound is apply | coated on a 1st light emitting layer, a 1st intermediate layer is formed, and polymerization property is carried out. A coating solution for forming a second intermediate layer containing a conductive polymer having no group and a fluorinated solvent is applied on the first intermediate layer to form a second intermediate layer, and a third intermediate layer containing a metal compound is formed. It is preferable to apply a coating solution on the second intermediate layer to form a third intermediate layer.

Next, the second light emitting layer 14 is formed on the intermediate layer 13. The method of forming the second light emitting layer 14 may be a wet method or an evaporation method, but it is preferable to form the second light emitting layer 14 by a wet method from the viewpoint of reducing the manufacturing cost of the organic thin film laminate 10.
As described above, the organic thin film laminate according to the present invention can be manufactured.

  When the first light emitting layer 12, the intermediate layer and the second light emitting layer 14 are all formed by a wet method, all the layers constituting the organic thin film laminate 10 can be formed by a wet method, thereby further reducing the manufacturing cost. can do.

  Although the intermediate layer is formed on the first light emitting layer as the organic functional layer in the method of manufacturing the organic thin film laminate, the intermediate layer is formed on the second light emitting layer as the organic functional layer. Alternatively, an intermediate layer may be formed on each of the first light emitting layer and the second light emitting layer.

<< Overview of Organic Electroluminescent Device >>
An organic EL device according to the present invention is characterized by including the above-described organic thin film laminate.

FIG. 2 shows a schematic cross-sectional view of the organic EL element of the present embodiment.
As shown in FIG. 2, the organic EL element 20 includes a base 21, an anode 22, a first light emitting unit 23, an intermediate layer 24, a second light emitting unit 25, and a cathode 26. Specifically, the anode 22 is formed on the substrate 21. Further, the first light emitting unit 23 and the second light emitting unit 25 are stacked on the anode 22 with the intermediate layer 24 interposed therebetween. Furthermore, a cathode 26 is provided on the second light emitting unit 25. Thus, the first light emitting unit 23, the intermediate layer 24, and the second light emitting unit 25 are sandwiched between the anode 22 and the cathode 26.

  In addition, in the organic EL element 20, the configuration in which the first light emitting unit 23 and the second light emitting unit 25 are stacked via the intermediate layer 24 has the same configuration as that of the embodiment of the organic thin film stack described above. Can. For this reason, the organic EL element 20 is a structure provided with the above-mentioned organic thin film laminated body as a light emitting element.

Hereinafter, each configuration of the organic EL element 20 will be described.
The base 21 and the intermediate layer 24 can have the same configuration as the base 11 and the intermediate layer 13 of the organic thin film laminate described above.
Each of the first light emitting unit 23 and the second light emitting unit 25 has at least one or more first and second light emitting layers. The first light emitting layer included in the first light emitting unit 23 can have the same configuration as the first light emitting layer of the embodiment of the organic thin film stack described above. The second light emitting layer included in the second light emitting unit 25 can have the same configuration as the second light emitting layer of the embodiment of the organic thin film laminate described above.

Although the following structures can be mentioned as a typical element structure of an organic EL element, It is not limited to these.
(1) Light emitting layer (2) Light emitting layer / electron transport layer (3) Hole transport layer / light emitting layer (4) Hole transport layer / light emitting layer / electron transport layer (5) Hole transport layer / light emitting layer / electron Transport layer / electron injection layer (6) Hole injection layer / hole transport layer / light emitting layer / electron transport layer (7) hole injection layer / hole transport layer / (electron blocking layer /) light emitting layer / (hole) Blocking Layer /) Electron Transporting Layer / Electron Injection Layer Among the above, the configuration of (7) is preferably used, but is not limited thereto.

  In the above configuration, the first light emitting layer is formed of a single layer or a plurality of layers. In addition, if necessary, a hole blocking layer (hole barrier layer), an electron injection layer (cathode buffer layer) or the like may be provided between the first light emitting layer and the cathode, and the first light emitting layer An electron blocking layer (electron barrier layer), a hole injection layer (anode buffer layer) or the like may be provided between it and the anode. A well-known material and manufacturing method can be employ | adopted for these.

<< Method of manufacturing organic electroluminescent device >>
Next, the manufacturing method of the organic EL element of this invention is demonstrated.
The method for producing an organic EL device according to the present invention is a method for producing an organic electroluminescent device comprising an organic thin film laminate in which a plurality of organic functional layers made of a non-hardenable material are laminated between an anode and a cathode. And forming an organic functional layer using a solution of an organic functional layer material by dissolving it in a polar solvent other than a fluorinated solvent, and forming an intermediate layer of at least one layer made of a non-hardenable material And forming the at least one intermediate layer, the conductive polymer not having at least a polymerizable group is dissolved in a fluorinated solvent in forming the intermediate layer of any of the at least one intermediate layers. It is characterized by using a solution.

  Since the organic EL element to manufacture is the same as the structure shown in FIG. 2, in the following description, the code | symbol used by FIG. 2 is used and detailed description of each structure is abbreviate | omitted.

First, the anode 22 is formed on the substrate 21.
Next, the first light emitting unit 23 (a hole injection layer, a hole transport layer, a first light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc.) is formed on the anode 22. The first light emitting layer of the first light emitting unit 23 is formed using the first light emitting layer material soluble in polar solvents other than fluorinated solvents.
Next, an intermediate layer 24 is formed on the first light emitting unit 23 using a non-curable material and a fluorinated solvent. When the intermediate layer 13 has a single-layer structure, it is preferable to form the intermediate layer 13 by a wet method using a coating solution for forming an intermediate layer containing a non-curable material and a fluorinated solvent. Moreover, when the intermediate layer 13 is comprised by multiple layers, the coating liquid for 1st intermediate layer formation containing a metal compound is apply | coated on a 1st light emitting layer, a 1st intermediate layer is formed, and polymerization property is carried out. A coating solution for forming a second intermediate layer containing a conductive polymer having no group and a fluorinated solvent is applied on the first intermediate layer to form a second intermediate layer, and a third intermediate layer containing a metal compound is formed. It is preferable to apply a coating solution on the second intermediate layer to form a third intermediate layer.
Next, a second light emitting unit 25 (a hole injection layer, a hole transport layer, a second light emission layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc.) is formed on the intermediate layer 24. It is preferable to form each layer constituting the second light emitting unit 25 by a wet method.
Next, the cathode 26 is formed on the second light emitting unit 25.

  As a formation method of each layer which constitutes organic EL element 20, it may be any method, such as a wet method, vapor deposition, and sputtering, as mentioned above.

Finally, the laminate formed up to the cathode 26 is sealed. A well-known member and method can be used as a sealing means used for sealing of the said laminated body.
The organic EL element 20 can be manufactured as described above.

In addition, in the manufacturing method of the said organic EL element, although it laminated | stacked and manufactured in order from the anode side, it may be an inverse product system (inverted system) laminated | stacked and manufactured in order from a cathode side.
In the method of manufacturing the organic EL element, although the intermediate layer is formed on the first light emitting unit including the first light emitting layer as the organic functional layer, the second light emitting layer as the organic functional layer is included. An intermediate layer may be formed on the two light emitting units, or an intermediate layer may be formed on each of the first light emitting unit and the second light emitting unit.

<< Application >>
The organic EL element of the embodiment described above is a surface light emitter, and thus can be used as various light emission sources. For example, lighting devices such as home lighting and car lighting, backlights for watches and liquid crystals, lights for advertising billboards, light sources for traffic lights, light sources for optical storage media, light sources for electrophotographic copiers, light sources for optical communication processors, Although the light source of a light sensor etc. are mentioned, it is not limited to this, It can use effectively as a back light of a liquid crystal display combined with a color filter, and an application as a light source for lighting.

  Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, it represents "mass part" or "mass%."

Example 1
<< Preparation of Organic Thin Film Laminate 101>
As described below, the first light emitting layer, the intermediate layer and the second light emitting layer were formed on the substrate and sealed, to obtain an organic thin film laminate 101 having a light emitting area of 5 cm × 5 cm.

(Preparation of base material)
First, atmospheric pressure plasma discharge treatment described in Japanese Patent Application Laid-Open No. 2004-68143 on the entire surface of the polyethylene naphthalate film (manufactured by Teijin DuPont, hereinafter abbreviated as PEN) on which the first electrode layer is formed. Using an apparatus, an inorganic gas barrier layer made of SiOx was formed to have a layer thickness of 500 nm. As a result, a flexible substrate having gas barrier properties having an oxygen permeability of 0.001 mL / m ² / day or less and a water vapor permeability of 0.001 g / m ² / day or less was produced.

(Formation of first electrode layer)
A film of ITO (indium-tin oxide) having a thickness of 120 nm was formed on the substrate by sputtering, and patterning was performed by photolithography to form a first electrode layer. The pattern was such that the area of the light emitting region was 5 cm × 5 cm.

(Formation of the first light emitting layer)
After preparing the following first light emitting layer material, the first light emitting layer material is coated at 5 m / min by a die coating method on the substrate on which the first electrode layer is formed, and after natural drying, it is at 120 ° C. It hold | maintained for 30 minutes, and formed the 1st light emitting layer of layer thickness 40 nm.

<First light emitting layer material>
Host compound S-1: 9.5 parts by mass Phosphorescent light emitting dopant D-75: 0.04 parts by mass Isopropyl acetate: 2000 parts by mass

(Formation of middle layer)
2,2,3,3-Tetrafluoro-1-propanol (1H, 1H, 3H-tetrafluoropropanol, TFPO) containing 1% by mass of ZnO fine particles (ZnONPs, average particle diameter 10 nm) on the first light emitting layer The solution was applied at 5 m / min by die coating to form a first intermediate layer having a dry layer thickness of 10 nm.
Subsequently, a 2,2,3,3-tetrafluoro-1-propanol (TFPO) solution containing 0.5% by mass of polyethyleneimine (PEI: manufactured by Sigma Aldrich Japan, weight average molecular weight 25000) is die-coated. After applying at 5 m / min, it was dried at 120 ° C. for 10 minutes to form a second intermediate layer having a dry layer thickness of 20 nm.
The TFPO used for forming the first and second intermediate layers had a water content of 13 ppm as measured by the Karl Fischer method.
Subsequently, an acetonitrile (AN) solution containing 0.1% by mass of phosphomolybdic acid n hydrate (PMA: manufactured by Kanto Chemical Co., Ltd.) is applied at a rate of 5 m / min by a die coating method, and then 10 at 100 ° C. It was dried for a minute to form a third intermediate layer having a dry layer thickness of 10 nm.

(Formation of hole transport layer)
Furthermore, using a hole transport layer composition of the following composition, it is applied at 5 m / min by a die coating method, naturally dried, and then held at 130 ° C. for 30 minutes to form a hole transport layer with a layer thickness of 20 nm. did.

Hole transport material (the following compound (60)) (weight average molecular weight Mw = 80000)
10 parts by mass Chlorobenzene (CB): 3000 parts by mass

(Formation of second light emitting layer)
Next, on the intermediate layer, the second light emitting layer material was applied by die coating at 5 m / min, naturally dried, and then held at 120 ° C. for 30 minutes to form a second light emitting layer with a layer thickness of 40 nm. .

<Second light emitting layer material>
Host compound S-1: 9.5 parts by mass Phosphorescent light emitting dopant D-75: 0.04 parts by mass 2,2,3,3-tetrafluoro-1-propanol (TFPO): 2000 parts by mass

(Sealing)
The sealing base material was adhered to the organic thin film laminate formed by the above steps using a commercially available roll laminating apparatus.
Bonding with a layer thickness of 1.5 μm using a two-component reactive urethane adhesive for dry lamination on a flexible 30 μm thick aluminum foil (made by Toyo Aluminum Co., Ltd.) as a sealing base material Agent layer, and laminated with a 12 μm thick polyethylene terephthalate (PET) film.

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

As a 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 type curing accelerator

The sealing base material was closely attached and disposed, and pressure sealing was performed using a pressure bonding roll at a pressure bonding roll temperature of 120 ° C., a pressure of 0.5 MPa, and an apparatus speed of 0.3 m / min.
As described above, an organic thin film stack 101 having a total thickness of 130 nm and having the same form as the organic thin film stack having the configuration shown in FIG. 1 was produced. In the present embodiment, the total layer thickness refers to the sum of the layer thicknesses of the first light emitting layer, the first to third intermediate layers, the hole transporting layer, and the second light emitting layer.

<< Preparation of Organic Thin Film Laminate 102>
An organic thin film stack is prepared in the same manner as the organic thin film stack 101 except that TFPO used for forming the first and second intermediate layers is changed to 1H, 1H, 5H-octafluoropentanol (OFAO). 102 was produced.

<< Preparation of Organic Thin Film Laminate 103>
An organic thin film stack 103 was manufactured in the same manner as the organic thin film stack 101 except that the first light emitting layer was formed under the following conditions.
After preparing the following first light emitting layer material, the first light emitting layer material is coated at 5 m / min by a die coating method on the substrate on which the first electrode layer is formed, and after natural drying, it is at 130 ° C. It hold | maintained for 30 minutes and formed. Thus, a first light emitting layer having a layer thickness of 40 nm was formed.

<First light emitting layer material>
Host compound (the above compound (60)) (weight-average molecular weight Mw = 80000)
7 parts by mass Phosphorescent light emitting dopant D-75: 0.05 parts by mass chlorobenzene: 1000 parts by mass

<< Preparation of Organic Thin Film Laminate 104>
In the preparation of the organic thin film laminate 101, the first to third intermediate layers, the hole transport layer, and the second light emitting layer are not formed, and only TFPO is directly on the first light emitting layer in the same manner as the second light emitting layer. An organic thin film laminate 104 was produced in the same manner as described above except that the coating (rinsing) was performed under the film forming conditions of (1).

<< Preparation of Organic Thin Film Laminate 105>
An organic thin film laminate 105 was produced in the same manner as in the production of the organic thin film laminate 101 except that the TFPO used for forming the first and second intermediate layers was changed to isopropanol (IPA).
By using isopropanol to form the first and second intermediate layers, the first light emitting layer having a layer thickness of 40 nm was partially melted, and as shown in Table 1, the total layer thickness of the organic thin film laminate 105 was reduced to 105 nm. .

<< Preparation of Organic Thin Film Laminate 106>
An organic thin film stack 106 was produced in the same manner as the production of the organic thin film stack 103 except that the TFPO used for forming the first and second intermediate layers was changed to isopropanol (IPA).
By using isopropanol to form the first and second intermediate layers, the first light emitting layer having a layer thickness of 40 nm was partially melted out, and the total layer thickness of the organic thin film laminate 106 was reduced to 115 nm as shown in Table 1. .

<< Preparation of Organic Thin Film Laminate 107>
An organic thin film laminate 107 was produced in the same manner as in the production of the organic thin film laminate 104 except that TFPO to be rinsed on the first light emitting layer was changed to isopropanol (IPA).
By rinsing with isopropanol, the first light emitting layer having a layer thickness of 40 nm was partially dissolved, and as shown in Table 1, the total layer thickness of the organic thin film laminate 107 was reduced to 15 nm.

<< Preparation of Organic Thin Film Laminate 108>
An organic thin film stack 108 was produced in the same manner as the production of the organic thin film stack 101 except that the first to third intermediate layers, the hole transport layer and the second light emitting layer were not formed.

<< Evaluation of Organic Thin Film Laminates 101 to 108 >>
The following evaluation was performed about the organic thin-film laminated body 101-108 produced as mentioned above. The evaluation results are shown in Table 1.

(1) Rinse-out amount test of first light emitting layer The first light emitting layer of each organic thin film laminate was formed on a quartz substrate under the same conditions as in the preparation of the organic thin film laminate, dried, and cut into 30 mm squares. Next, using UV-3310 (manufactured by Hitachi, Ltd.), the ultraviolet-visible spectral absorption spectrum of the cut-out quartz substrate was measured to obtain an absorption spectrum before rinsing. Subsequently, 0.2 mL of the solvent used for the first intermediate layer of each organic thin film laminate is dropped on the dried film of the cut-out substrate, spin-coated at 500 rpm for 30 seconds, and again UV-visible spectral absorption The spectrum was measured and taken as a spectrum after rinsing. Calculate the value (100-(strength after rinse / strength before rinse)) obtained by subtracting 100% from the intensity ratio (%) at the peak in the wavelength range of 200 nm to 600 nm of the UV-visible spectrum before and after rinse It was the rinse-out amount (%) of the thin film laminate.

(2) Measurement of luminescence amount The luminescence intensity of the maximum wavelength of the luminescence spectrum when exciting each produced organic thin film laminate at an excitation wavelength of 320 nm was measured using a fluorometer F-4500 (manufactured by Hitachi, Ltd.), The light emission amount was taken. Then, the light emission amount of each organic thin film stack was determined as a relative value based on the light emission amount of the organic thin film stack 104 as 100.

(3) Measurement of fluorinated solvent content A thin film laminate is formed on a 30 mm square glass substrate in the same manner as each of the above organic thin film laminates 101 to 105, and then a part of the thin film laminate is cleaned with a clean wiper soaked with toluene. After peeling off and sputtering an Ag thin film using SC-701 MkII ECO manufactured by Sanyu Electronics Co., Ltd., a step difference at the boundary where the thin film laminated body was peeled off was measured using WYKO manufactured by Veeco, and the film thickness was determined. Furthermore, after forming each thin film laminate on a 30 mm square glass substrate in the same manner as above, the wafer was cut to about 10 mm square, and the film area was determined from the weight ratio before and after. The silicon wafer whose area is determined is measured by a temperature rising thermal desorption analyzer manufactured by Electronic Science Co., Ltd., and the desorbed gas component is quantified from the mass fragment spectrum corresponding to the used fluorinated solvent to obtain each organic layer laminate The mass ratio of fluorinated solvent per volume was determined. In Table 1, the case where no dominant peak is detected in the mass fragment spectrum corresponding to each fluorinated solvent is indicated as "nd" (not detected).

  As shown in Table 1, the organic thin film laminates 101 to 103 in which the intermediate layer is formed using the conductive polymer having no polymerizable group and the fluorinated solvent have an emission amount compared to the organic thin film laminates 104 to 108. Indicates a light emission amount of about 1.5 times or more. Therefore, according to the method for producing an organic thin film laminate of the present invention, even if the intermediate layer is formed by a wet method, it can be said that it is possible to produce an organic thin film laminate in which the functional deterioration is suppressed.

  As described above, in the method for producing an organic thin film laminate, the solvent contained in the coating solution for forming an intermediate layer by forming the intermediate layer using the conductive polymer having no polymerizable group and the fluorinated solvent. Damage to the lower layer (the first light emitting layer side) due to In addition, since the intermediate layer thus formed can block the solvent contained in the upper layer forming coating solution, when the upper layer (the second light emitting layer side) is formed by the wet method, the lower layer (the first layer) can be formed. It is possible to reduce the damage caused by the solvent to the light emitting layer side). In addition, since the intermediate layer is made of a non-hardening material, high temperature curing treatment such as heating can be omitted, and an organic thin film laminate can be produced on a resin base using a wet method. For this reason, without reducing the performance of the lower first light emitting layer, it is possible to stably obtain the effect of increasing the light emission amount by the laminated structure.

Example 2
<< Preparation of Organic EL Element 201 >>
As described below, the anode / first light emitting unit (hole injection layer / hole transport layer / first light emission layer / electron transport layer / electron injection layer) / intermediate layer (first intermediate layer / first layer) on the substrate Form a bottom emission type organic EL device consisting of 2 intermediate layer / third intermediate layer) / second light emitting unit (hole transport layer / second light emitting layer / electron transport layer / electron injection layer) / cathode Were sealed to obtain an organic EL element 201.

(Preparation of base material)
First, an atmospheric pressure plasma discharge treatment apparatus described in JP-A-2004-68143 is used on the entire surface of the polyethylene naphthalate film (manufactured by Teijin DuPont, hereinafter abbreviated as PEN) on which the anode is formed. Then, an inorganic gas barrier layer made of SiOx was formed to have a layer thickness of 500 nm. As a result, a flexible substrate having gas barrier properties having an oxygen permeability of 0.001 mL / m ² / day or less and a water vapor permeability of 0.001 g / m ² / day or less was produced.

(Formation of anode)
A 120 nm-thick ITO (indium-tin oxide) film was formed on the above-mentioned base material by a sputtering method, and patterning was performed by a photolithography method to form an anode. The pattern was such that the area of the light emitting region was 5 cm × 5 cm.

(Formation of first light emitting unit-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 is isopropyl alcohol on a substrate on which an anode is formed. The 2% by mass solution diluted by the above was coated by a die coating method and naturally dried to form a hole injection layer having a layer thickness of 40 nm.

(Formation of first light emitting unit-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 hole transport layer composition of the following composition was used at a dye coating method at 5 m / min. After coating and natural drying, the film was held at 130 ° C. for 30 minutes to form a hole transport layer having a layer thickness of 30 nm.

<Hole transport layer composition>
Hole transport material (the above compound (60)) (weight average molecular weight Mw = 80000)
10 parts by mass chlorobenzene: 3000 parts by mass

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

<First light emitting layer material>
Host compound S-3: 9.5 parts by mass Phosphorescent light emitting dopant D-71: 0.04 parts by mass Isopropyl acetate: 2000 parts by mass

(Formation of the first intermediate layer)
A 2,2,3,3-tetrafluoro-1-propanol (TFPO) solution containing 1% by mass of ZnO fine particles (ZnONPs, average particle diameter: 10 nm) on the first light emitting layer at a distance of 5 m / min by a die coating method The coating was applied to form a first intermediate layer having a dry layer thickness of 10 nm.

(Formation of the second intermediate layer)
Subsequently, 2,2,3,3-tetrafluoro-1-propanol (TFPO) containing 0.5% by mass of polyethyleneimine (PEI: manufactured by Sigma Aldrich Japan, weight average molecular weight 25000) on the first intermediate layer The solution was applied at 5 m / min by a die coating method, and then dried at 120 ° C. for 10 minutes to form a second intermediate layer having a dry layer thickness of 20 nm.
The TFPO used for the formation of the first and second intermediate layers had a water content of 13 ppm according to the Karl Fischer method.

(Formation of the third intermediate layer)
Subsequently, a 0.1 mass% acetonitrile (AN) solution of phosphomolybdic acid n hydrate (PMA: made by Kanto Chemical Co., Ltd.) is applied on the second intermediate layer by the die coating method at 5 m / min. It was dried at 100 ° C. for 10 minutes to form a third intermediate layer having a dry layer thickness of 10 nm.

(Formation of second light emitting unit-hole transport layer / second light emitting layer / electron transport layer / electron injection layer)
After the hole transport layer of the first light emitting unit and the hole transport layer and the second light emitting layer having the same configuration as the first light emitting layer are formed on the third intermediate layer, the electron transport layer and the electrons are as follows. An injection layer was formed.

(Formation of second light emitting unit-electron transport layer)
On the second light emitting layer, a solution of 2,2,3,3-tetrafluoro-1-propanol (TFPO, 3 carbon atoms) containing 1% by mass of ZnO fine particles (ZnONPs, average particle diameter 10 nm) is die-coated. It coated by 5 m / min and formed the electron carrying layer of layer thickness 10 nm.

(Formation of second light emitting unit-electron injection layer)
Subsequently, 2,2,3,3-tetrafluoro-1-propanol (TFPO) containing 0.5% by mass of polyethyleneimine (PEI: manufactured by Sigma Aldrich Japan, weight average molecular weight 25000) on the first intermediate layer The solution was applied at 5 m / min by a die coating method, and then dried at 120 ° C. for 10 minutes to form an electron injection layer having a layer thickness of 10 nm.
The TFPO used had a water content of 13 ppm according to the Karl-Fisher method.

(Formation of cathode)
Next, aluminum was vapor-deposited on the electron injection layer of the second light emitting unit to form a cathode with a thickness of 100 nm.

(Sealing)
It sealed by the same process as Example 1, and produced organic EL element 201.

<< Preparation of Organic EL Element 202 >>
The 2,2,3,3-tetrafluoro-1-propanol (TFPO) used in the formation of the first and second intermediate layers in the preparation of the organic EL element 201 is 1H, 1H, 5H-octafluoropentanol ( An organic EL element 202 was produced in the same manner except that it was changed to OFAO).

<< Preparation of Organic EL Element 203 >>
An organic EL element 203 was produced in the same manner as the production of the organic EL element 201 except that the first light emitting layer was formed under the following conditions.
The substrate on which the hole transport layer is formed is fixed to a substrate holder of a commercially available vacuum deposition apparatus, 200 mg of host compound S-3 is put in a molybdenum resistance heating boat, and a phosphorescent light emitting dopant D is put in another molybdenum resistance heating boat. 100 mg of -71 was loaded and attached to a vacuum evaporation apparatus.

Next, the vacuum chamber is depressurized to 4 × 10 ⁻⁴ Pa, and then the heating boat containing the host and the dopant is heated while being energized, and the hole transport layer is deposited at a deposition rate of 1 nm / sec and 0.004 nm / sec, respectively. It co-evaporated on it and formed the 1st light emitting layer with a layer thickness of 40 nm. In addition, the substrate temperature at the time of vapor deposition was room temperature.

<< Preparation of Organic EL Element 204 >>
An organic EL element 204 was produced in the same manner as the production of the organic EL element 201 except that the first intermediate layer was not formed.

<< Production of Organic EL Element 205 >>
An organic EL element 205 was produced in the same manner as the production of the organic EL element 201 except that the second intermediate layer was not formed.

<< Preparation of Organic EL Element 206 >>
0.1 mass% acetonitrile (AN) solution of phosphomolybdic acid n-hydrate (PMA: manufactured by Kanto Chemical Co., Ltd.) used for forming the third intermediate layer in the preparation of the organic EL element 201 as WO ₃ nanoparticles An organic EL element 206 was produced in the same manner as in the above, except that the dispersion was changed to a 0.1 mass% isopropanol (IPA) dispersion liquid (WO ₃ NPs, average particle diameter 10 nm).

<< Production of Organic EL Element 207 >>
An organic EL element 207 was produced in the same manner as the production of the organic EL element 201 except that the third intermediate layer and the second light emitting unit were not formed.

<< Preparation of organic EL element 208 >>
An organic EL element 208 was produced in the same manner as the production of the organic EL element 207 except that the hole injection layer of the first light emitting unit was formed as follows.
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 0.1 mass% acetonitrile (AN) solution of phosphomolybdic acid n hydrate (PMA: made by Kanto Chemical Co., Ltd.) was applied at a rate of 5 m / min by a die coating method on the substrate on which the anode was formed. Thereafter, it was dried at 100 ° C. for 10 minutes to form a hole injection layer having a layer thickness of 40 nm.

<< Fabrication of Organic EL Element 209>
An organic EL element 209 was produced in the same manner as the production of the organic EL element 207 except that the first light emitting layer was formed under the following conditions.
The substrate on which the hole transport layer is formed is fixed to a substrate holder of a commercially available vacuum deposition apparatus, 200 mg of host compound S-3 is put in a molybdenum resistance heating boat, and a phosphorescent light emitting dopant D is put in another molybdenum resistance heating boat. 100 mg of -71 was loaded and attached to a vacuum evaporation apparatus.

Next, the vacuum chamber is depressurized to 4 × 10 ⁻⁴ Pa, and then the heating boat containing the host and the dopant is heated while being energized, and the hole transport layer is deposited at a deposition rate of 1 nm / sec and 0.004 nm / sec, respectively. It co-evaporated on it and formed the 1st light emitting layer with a layer thickness of 40 nm. In addition, the substrate temperature at the time of vapor deposition was room temperature.

<< Preparation of Organic EL Element 210 >>
An organic EL element 210 was produced in the same manner as the production of the organic EL element 207 except that the first intermediate layer was not formed.

<< Preparation of Organic EL Element 211>
An organic EL element 211 was produced in the same manner as the production of the organic EL element 207 except that the second intermediate layer was not formed.

<< Production of Organic EL Element 212 >>
In the preparation of the organic EL element 207, an organic compound is prepared in the same manner except that 2,2,3,3-tetrafluoro-1-propanol (TFPO) used for forming the second intermediate layer is changed to isopropanol (IPA). An EL element 212 was produced.

<< Preparation of Organic EL Element 213 >>
In the preparation of the organic EL element 207, except that 2,2,3,3-tetrafluoro-1-propanol (TFPO) used for forming the first intermediate layer and the second intermediate layer is changed to isopropanol (IPA) Similarly, an organic EL element 213 was produced.

<< Preparation of Organic EL Element 214 >>
An organic EL element 214 was produced in the same manner as the production of the organic EL element 201 except that the method of forming the second intermediate layer was changed to the following method.
On the first intermediate layer, a 0.5% by mass TFPO solution of DBp-6 and AIp-4 (each ratio is 50.0% by mass: 50.0% by mass) represented by the following structural formula is formed by a die coating method. After film formation and film formation, UV irradiation is performed at 130 ° C. for 30 seconds using a low pressure mercury lamp (15 mW / cm ² ) to photocure the DBp-6 and AIp-4 polymerizable groups and have a polymerizable group An insolubilized n-type second intermediate layer having a dry layer thickness of 10 nm containing a conductive polymer was provided.

<< Preparation of Organic EL Element 215 >>
An organic EL element 215 was produced in the same manner as in the production of the organic EL element 201 except that the compound ET-11 represented by the following structural formula was used instead of the polyethyleneimine used to form the second intermediate layer. did.

<< Preparation of Organic EL Element 216 >>
In the preparation of the organic EL element 201, polyethyleneimine ethoxide (PEIE: manufactured by Sigma Aldrich Japan Co., Ltd., 80%) instead of the polyethyleneimine used for forming the second intermediate layer without forming the first and third intermediate layers An organic EL device 216 was produced in the same manner as in Example 1 except that an ethoxylated product having a weight average molecular weight of 70000 was used.

<< Preparation of Organic EL Element 217 >>
In the preparation of the organic EL element 201, polyethyleneimine ethoxide (PEIE: manufactured by Sigma-Aldrich Japan Co., Ltd., 80% ethoxylated product instead of polyethyleneimine used for forming the second intermediate layer without forming the third intermediate layer) An organic EL device 217 was produced in the same manner as described above except that a weight average molecular weight of 70000 was used.

<< Production of Organic EL Element 218 >>
An organic EL element 218 was produced in the same manner as in the production of the organic EL element 201 except that the compound ET-101 represented by the following structural formula was used instead of the polyethyleneimine used to form the second intermediate layer. did.

<< Fabrication of Organic EL Element 219>
An organic EL element 219 was produced in the same manner as the production of the organic EL element 201 except that the method of forming the first intermediate layer and the second intermediate layer was changed to the following method.
2,2,3,3-tetrafluoro- containing 0.5% by mass of polyethyleneimine ethoxide (PEIE: 80% ethoxylated product manufactured by Sigma Aldrich Japan, weight average molecular weight 70000) on the first light emitting layer After 1-propanol (TFPO) solution was applied at 5 m / min by a die coating method, it was dried at 120 ° C. for 10 minutes to form a first intermediate layer having a dry layer thickness of 10 nm.
Next, on the first intermediate layer, polyethylene imine ethoxide (PEIE: manufactured by Sigma Aldrich Japan, 80% ethoxylated product, weight average molecular weight 70000) and phosphomolybdic acid n-hydrate (PMA: manufactured by Kanto Chemical Co., Ltd.) 2.) a mixed solution of 2,2,3,3-tetrafluoro-1-propanol (TFPO): acetonitrile (AN) containing 0.5% by mass of a 9: 1 (volume ratio) mixture) (TFPO: AN = 9: 1) After applying (volume ratio) at 5 m / min by a die coating method, it was dried at 120 ° C. for 10 minutes to form a second intermediate layer having a dry layer thickness of 10 nm.
The TFPO used for the formation of the first and second intermediate layers had a water content of 13 ppm according to the Karl Fischer method.

<< Preparation of Organic EL Element 220 >>
An organic EL element 220 was produced in the same manner as the production of the organic EL element 201 except that the method of forming the third intermediate layer was changed to the following method.
A 0.5% by mass solution obtained by diluting 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 is diluted with isopropyl alcohol. It applied by a method and air-dried, and formed the 3rd intermediate layer of dry layer thickness 10 nm.

<< Preparation of Organic EL Element 221 >>
In the preparation of the organic EL element 201, polyethylene imine ethoxide (PEIE: manufactured by Sigma Aldrich Japan, 80% ethoxylated product, weight average molecular weight 70000) is used instead of polyethylene imine used for forming the second intermediate layer An organic EL element 221 was produced in the same manner as described above.

<< Production of Organic EL Element 222 >>
In the preparation of the organic EL element 201, in place of phosphomolybdic acid n hydrate (PMA: manufactured by Kanto Chemical Co., Ltd.) used for forming the third intermediate layer, tungst (VI) phosphoric acid n hydrate ( PWA: An organic EL device 222 was produced in the same manner as in Kanto Chemical Co., Ltd.).

<< Preparation of Organic EL Element 223 >>
Sodium phosphotungstate (PMANa: manufactured by Kanto Chemical Co., Ltd.) in place of phosphomolybdic acid n hydrate (PMA: manufactured by Kanto Chemical Co., Ltd.) used to form the third intermediate layer in the preparation of the organic EL element 201 The organic EL element 223 was produced similarly except using.

<< Preparation of Organic EL Element 224 >>
An organic EL element 224 was produced in the same manner as the production of the organic EL element 201 except that the method of forming the third intermediate layer was changed to the following method.
After applying a 0.1 mass% isopropanol (IPA) solution of NiO fine particles (NiONPs, average particle diameter 10 nm) at 5 m / min by a die coating method on the second intermediate layer, it is dried at 100 ° C. for 10 minutes, A third intermediate layer having a thickness of 10 nm was formed.

<< Preparation of Organic EL Element 225 >>
In the preparation of the organic EL element 201, the solvent used in the formation of the first and second intermediate layers is changed to 1H, 1H-trifluoroethanol (TFEO, fluoroalcohol having 2 carbon atoms) in the same manner, The organic EL element 225 was produced.

<< Preparation of Organic EL Element 226 >>
In the preparation of the organic EL element 201, the same procedure is followed except that the solvent used to form the first and second intermediate layers is changed to 2- (perfluorobutyl) ethanol (FBEO, fluoroalcohol having 6 carbon atoms). The organic EL element 226 was produced.

<< Preparation of Organic EL Element 227 >>
An organic EL element 227 was produced in the same manner as in the production of the organic EL element 201 except that the solvent used for forming the first and second intermediate layers was changed to methyl perfluorobutyrate (MFBA).

<< Preparation of Organic EL Element 228 >>
In the preparation of the organic EL element 201, the solvent used to form the first and second intermediate layers is 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (FEFPE) The organic EL element 228 was similarly produced except having changed into.

<< Preparation of Organic EL Element 229>
In the preparation of the organic EL element 201, the same procedure is performed except that AZO fine particles (AZONPs, average particle diameter 10 nm) are used instead of ZnO fine particles (ZnONPs, average particle diameter 10 nm) used for forming the first intermediate layer. The organic EL element 229 was produced.

<< Production of Organic EL Element 230 >>
In the preparation of the organic EL element 201, TiO ₂ fine particles (TiO ₂ NPs, average particle diameter 10 nm) were used instead of ZnO fine particles (ZnONPs, average particle diameter 10 nm) used for forming the first intermediate layer Similarly, an organic EL element 230 was produced.

<< Preparation of Organic EL Element 231 >>
In the preparation of the organic EL element 201, the same procedure is carried out except using ZrO 2 particles (ZrONPs, average particle diameter 10 nm) in place of ZnO particles (ZnONPs, 10 nm average particle diameter) used to form the first intermediate layer. The organic EL element 231 was produced.

<< Preparation of Organic EL Element 232 >>
In the preparation of the organic EL element 201, Y ₂ O ₃ fine particles (Y ₂ O ₃ NPs, average particle diameter 10 nm) are used instead of ZnO fine particles (ZnONPs, average particle diameter 10 nm) used for forming the first intermediate layer An organic EL element 232 was produced in the same manner except that it was used.

<< Fabrication of Organic EL Element 233>
In the preparation of the organic EL element 201, the same procedure is carried out except that YSZ fine particles (YSZNPs, average particle diameter 10 nm) are used instead of ZnO fine particles (ZnONPs, average particle diameter 10 nm) used for forming the first intermediate layer. The organic EL element 233 was produced.

<< Preparation of Organic EL Element 234 >>
In the preparation of the organic EL element 201, the same procedure is performed except that ITO fine particles (ITONPs, average particle size 10 nm) are used instead of ZnO fine particles (ZnONPs, average particle size 10 nm) used for forming the first intermediate layer. The organic EL element 234 was produced.

<< Preparation of Organic EL Element 235>
In the preparation of the organic EL element 201, the same procedure is performed except that GZO fine particles (GZONPs, average particle diameter 10 nm) are used instead of ZnO fine particles (ZnONPs, average particle diameter 10 nm) used for forming the first intermediate layer. The organic EL element 235 was produced.

<< Evaluation of Organic EL Elements 201-235 >>
The following evaluation was performed about the organic EL elements 201-235 produced as mentioned above. The evaluation results are shown in Tables 2 and 3.

(1) Rinse-out amount test of first light-emitting layer In the same manner as the rinse-out amount test of the first light-emitting layer in Example 1, organic light-emitting elements 201-235 for the first light-emitting layers of organic EL elements 201-235. The amount of rinse-out by the solvent used for the first intermediate layer and the second intermediate layer was determined.

(2) Measurement of fluorinated solvent content In the same manner as in the measurement of fluorinated solvent content in the evaluation of the organic thin film laminate of Example 1 above, the fluorine relative to the total mass of the respective intermediate layers of the organic EL elements 201 to 235 The mass ratio of the organic solvent was determined. In Table 2, the case where no dominant peak is detected in the mass fragment spectrum corresponding to each fluorinated solvent is indicated as "nd" (not detected).

(3) Measurement of luminous efficiency Measurement of luminous efficiency is performed under constant current density conditions of ^2.5 mA / cm ² at room temperature (25 ° C.), and a spectroradiometer CS-2000 (manufactured by Konica Minolta Co., Ltd.) The light emission luminance of each element was measured using to determine the light emission efficiency (external extraction efficiency) at the current value. Then, the light emission efficiency of each element was determined as a relative value with the light emission efficiency of the organic EL element 207 as 100.

(4) Measurement of luminescence lifetime The luminescence lifetime is measured by continuously driving the organic EL device under conditions of room temperature 25 ° C. and humidity 55% RH, and measuring the luminance using the above-mentioned spectroradiometer CS-2000. The time required for the luminance to decrease by half (half life) was determined as a measure of the life. The driving condition was set to a current value of 10000 cd / m ² at the start of continuous driving. Then, the light emission lifetime of each element was determined as a relative value with the light emission lifetime of the organic EL element 207 as 100.

  As shown in Tables 2 and 3, the organic EL elements 201 to 204, 206 to 210, and 216 to 235 in which the intermediate layer is formed using the conductive polymer having no polymerizable group and the fluorinated solvent are organic EL elements. The light emission efficiency and the light emission lifetime show high values as compared with 205 and 211 to 215, and the light emission efficiency is twice or more and the light emission lifetime is four or more times. Therefore, according to the manufacturing method of the organic EL element of the present invention, even if the intermediate layer is formed by the wet method, it can be said that the organic EL element in which the functional deterioration is suppressed can be manufactured.

  Therefore, similarly to the method for producing the organic thin film laminate of Example 1, also in the method for producing an organic EL element, an intermediate layer is formed by using a conductive polymer having no polymerizable group and a fluorinated solvent, Damage to the lower layer (the first light emitting layer side) by the solvent contained in the intermediate layer forming coating solution can be reduced. In addition, since the intermediate layer thus formed can block the solvent contained in the upper layer forming coating solution, when the upper layer (the second light emitting layer side) is formed by the wet method, the lower layer (the first layer) can be formed. It is possible to reduce the damage caused by the solvent to the light emitting layer side). In addition, since each organic functional layer of the organic thin film laminate constituting the organic EL element is made of a non-hardening material, high temperature curing treatment such as heating can be omitted, and a wet method can be applied to a resin base. An organic EL element can be manufactured using it. For this reason, without reducing the performance of the lower first light emitting layer, it is possible to stably obtain the effect of increasing the light emission amount by the laminated structure.

[Example 3]
<< Preparation of Organic EL Element 301 >>
In the preparation of the organic EL element 201 of Example 2 described above, white organic light emission is produced similarly except that the method of forming the second light emitting layer, the electron transporting layer and the electron injecting layer of the second light emitting unit is changed as follows. An EL element 301 was produced.

(Formation of second light emitting unit-second light emitting layer)
A hole transport layer for the second light emitting unit having the same configuration as the first light emitting layer is provided on the third intermediate layer in the same manner as the preparation of the organic EL element 201, and the second light emitting layer material of the following composition is die-coated The coating solution was applied at 5 m / min and naturally dried, and then held at 120.degree. C. for 30 minutes to form a second light emitting layer having a layer thickness of 50 nm.

<Second light emitting layer material>
Host compound S-26: 9.5 parts by mass Phosphorescent emission dopant DP-1 (emission maximum wavelength 473 nm): 3 parts by mass Phosphorescent emission dopant D-68: 0.02 parts by mass Isopropyl acetate: 2000 parts by mass

(Formation of second light emitting unit-electron transport layer)
Subsequently, a 2,2,3,3-tetrafluoro-1-propanol (TFPO) solution containing 0.5% by mass of the above-mentioned compound ET-11 is applied at a speed of 5 m / min by a die coating method to give a natural appearance. After drying, it was kept at 120 ° C. for 30 minutes to form an electron transport layer with a layer thickness of 30 nm.

(Formation of second light emitting unit-electron injection layer)
Subsequently, the substrate was attached to a vacuum deposition apparatus without being exposed to the atmosphere. In addition, after adding potassium fluoride to a resistance heating boat made of molybdenum and attaching it to a vacuum deposition apparatus, the vacuum tank is depressurized to 4 × 10 ⁻⁵ Pa, and then the boat is energized to be heated and potassium fluoride is reduced to 0 It vapor-deposited on the electron carrying layer by .02 nm / sec, and formed the electron injection layer with a layer thickness of 2 nm.

(Formation of cathode)
Next, aluminum was vapor-deposited on the electron injection layer of the second light emitting unit to form a cathode with a thickness of 100 nm.

(Sealing)
It sealed by the process similar to Example 1, 2, and produced the organic EL element 301.

<< Production of Organic EL Element 302 >>
The 2,2,3,3-tetrafluoro-1-propanol (TFPO) used in the formation of the first and second intermediate layers in the preparation of the organic EL element 301 is 1H, 1H, 5H-octafluoropentanol ( An organic EL element 302 was produced in the same manner except that it was changed to OFAO).

<< Preparation of organic EL element 303 >>
The same as the preparation of the organic EL element 301 except that 2,2,3,3-tetrafluoro-1-propanol (TFPO) used to form the first and second intermediate layers is changed to isopropanol (IPA) The organic EL element 303 was manufactured.

<< Production of Organic EL Element 304 >>
In the preparation of the organic EL element 301, the hole injection layer of the first light emitting unit is formed as follows, and the first light emitting layer of the first light emitting unit to the hole transport layer of the second light emitting unit are not formed. An organic EL element 304 was produced in the same manner as described above.
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 0.1 mass% acetonitrile (AN) solution of phosphomolybdic acid n hydrate (PMA: made by Kanto Chemical Co., Ltd.) was applied at a rate of 5 m / min by a die coating method on the substrate on which the anode was formed. Thereafter, it was dried at 100 ° C. for 10 minutes to form a hole injection layer having a layer thickness of 10 nm.

<< Preparation of Organic EL Element 305>
An organic EL element 305 was produced in the same manner as the production of the organic EL element 304 except that the material of the second light emitting layer of the second light emitting unit was changed to the following composition.

<Second light emitting layer material>
Host compound S-26: 9.5 parts by mass Phosphorescent emitting dopant DP-1: 3 parts by mass Phosphorescent emitting dopant D-68: 0.02 parts by mass Phosphorescent emitting dopant D-76: 0.04 parts by mass Isopropyl acetate : 2000 parts by mass

<< Evaluation of Organic EL Elements 301-305 >>
With respect to the organic EL elements 301 to 305 manufactured as described above, the fluorinated solvent content, the luminous efficiency and the luminous life were measured in the same manner as in Example 2 above. The evaluation results are shown in Table 4.
The light emission efficiency and the light emission life of each element were determined as relative values based on the light emission efficiency and the light emission life of the organic EL element 305 as 100.

  As shown in Table 4, the organic EL elements 301 and 302 in which the intermediate layer is formed using the conductive polymer having no polymerizable group and the fluorinated solvent have luminous efficiency and light emission compared with the organic EL elements 303 to 305. Life is high. Therefore, according to the manufacturing method of the organic EL element of the present invention, even if the intermediate layer is formed by the wet method, it can be said that the organic EL element in which the functional deterioration is suppressed can be manufactured.

  Therefore, it is understood that the same effect as that of Example 2 can be obtained also in the white light emitting organic EL element.

Example 4
<< Fabrication of photoelectric conversion element 401 >>
As described below, on the substrate, cathode / electron injection layer / electron transport layer / first photoelectric conversion unit (first photoelectric conversion layer / first hole injection layer) / first intermediate layer / second intermediate layer / An inverted tandem-type photoelectric conversion element formed of the second photoelectric conversion unit (second photoelectric conversion layer / second hole injection layer) / anode was formed, and this was sealed to obtain a photoelectric conversion element 401.

(Preparation of base material)
First, an atmospheric pressure plasma discharge treatment apparatus described in JP-A-2004-68143 is used on the entire surface of a polyethylene naphthalate film (made by Teijin DuPont, hereinafter abbreviated as PEN) on the side where the cathode is formed. Then, an inorganic gas barrier layer made of SiOx was formed to have a layer thickness of 500 nm. As a result, a flexible substrate having gas barrier properties having an oxygen permeability of 0.001 mL / m ² / day or less and a water vapor permeability of 0.001 g / m ² / day or less was produced.

(Formation of cathode)
A 120 nm-thick ITO (indium-tin oxide) film was formed on the above-mentioned base material by a sputtering method, and patterning was performed by a photolithography method to form an anode. The pattern was such that the area of the light emitting region was 5 cm × 5 cm.

(Formation of electron injection layer-electron transport layer)
A 2,2,3,3-tetrafluoro-1-propanol (TFPO) solution containing 1% by mass of ZnO fine particles (ZnONPs, average particle diameter 10 nm) is applied at a speed of 5 m / min by a die coating method, and the layer thickness is 10 nm The electron injection layer of

  Subsequently, 2,2,3,3-tetrafluoro-1-propanol (TFPO) containing 0.5% by mass of polyethyleneimine (PEI: manufactured by Sigma Aldrich Japan, weight average molecular weight 25000) on the electron injection layer The solution was applied at 5 m / min by a die coating method, and then dried at 120 ° C. for 10 minutes to form an electron transport layer having a layer thickness of 20 nm.

(Formation of first photoelectric conversion unit (first photoelectric conversion layer-first hole injection layer))
A toluene solution in which 1.25 mass% of P3HT (manufactured by Sigma-Aldrich Japan) as a p-type semiconductor material and 1.0 mass% of Bis60PCBM (manufactured by Sigma-Aldrich Japan) as an n-type semiconductor material are dissolved on the electron transport layer And dried at 120 ° C. for 30 minutes to form a first photoelectric conversion layer with a layer thickness of 100 nm.

  A 2 mass% solution of a dispersion of poly (3,4-ethylenedioxythiophene) / polystyrene sulfonate (PEDOT / PSS) prepared in the same manner as in Examples 2 and 3 diluted with isopropyl alcohol is applied by a die coating method, It was naturally dried to form a first hole injection layer having a layer thickness of 40 nm.

(Formation of the first intermediate layer)
On the first photoelectric conversion unit, a 2,2,3,3-tetrafluoro-1-propanol (TFPO) solution containing 1% by mass of ZnO fine particles (ZnONPs, average particle diameter 10 nm) is die-coated at 5 m / min. To form a first intermediate layer having a dry layer thickness of 10 nm.

(Formation of the second intermediate layer)
Subsequently, 2,2,3,3-tetrafluoro-1-propanol (TFPO) containing 0.5% by mass of polyethyleneimine (PEI: manufactured by Sigma Aldrich Japan, weight average molecular weight 25000) on the first intermediate layer The solution was applied at 5 m / min by a die coating method, and then dried at 120 ° C. for 10 minutes to form a second intermediate layer having a dry layer thickness of 20 nm.
The TFPO used for the formation of the first and second intermediate layers had a water content of 13 ppm according to the Karl Fischer method.

(Formation of Second Photoelectric Conversion Unit (Second Photoelectric Conversion Layer-Second Hole Injection Layer))
Similarly to the first photoelectric conversion unit, the second photoelectric conversion layer and the second hole injection layer were formed.

(Formation of anode)
Next, gold was vapor-deposited on the second hole injection layer of the second photoelectric conversion unit to form an anode having a thickness of 100 nm.

(Sealing)
It sealed by the process similar to Examples 1-3, and the photoelectric conversion element 401 was produced.

<< Fabrication of photoelectric conversion element 402 >>
The same as in the preparation of the photoelectric conversion element 401, except that 2,2,3,3-tetrafluoro-1-propanol (TFPO) used for forming the first and second intermediate layers was changed to isopropanol (IPA). The photoelectric conversion element 402 was manufactured.

<< Evaluation of photoelectric conversion elements 401 and 402 >>
The following evaluation was performed about the photoelectric conversion elements 401 and 402 produced as mentioned above. The evaluation results are shown in Table 5.

(1) Rinse-out amount test of first hole injection layer In the same manner as the rinse-out amount test of the first light emitting layer in Example 1 described above, photoelectric conversion of the first hole injection layer of photoelectric conversion elements 401 and 402 is performed. The amount of rinse out with the solvent used for the first intermediate layer of the elements 401 and 402 was determined.

(2) Evaluation of photoelectric conversion efficiency and relative holding rate A mask with an effective area of 4.0 mm ² is superimposed on the light receiving part of the manufactured photoelectric conversion element, and 100 mW / cm ² of 100 mW / cm ² is obtained by a solar simulator (AM 1.5 G filter). It was irradiated with intense light. The short circuit current density Jsc (mA / cm ² ), the open circuit voltage Voc (V) and the curve factor (fill factor) FF are measured for each of the four light receiving portions formed on the photoelectric conversion element, The average value was calculated. Moreover, photoelectric conversion efficiency eta (%) was calculated | required according to following formula 1 using the calculated | required average value.

Formula 1: Jsc (mA / cm ² ) × Voc (V) × FF = η (%)
In Table 5, the photoelectric conversion efficiency is indicated by a relative value with the photoelectric conversion efficiency of the organic photoelectric conversion element 402 as 100.

Further, assuming that the initial photoelectric conversion efficiency at this time is 100, the photoelectric conversion efficiency after continuous irradiation for 100 hours at an irradiation intensity of 100 mW / cm ² with the resistance connected between the anode and the cathode is determined. The relative retention was calculated.

Formula 2: Relative holding ratio (%) = (1-photoelectric conversion efficiency in the initial stage / 100 photoelectric conversion efficiency after light irradiation) × 100
In Table 5, the relative holding ratio is indicated by a relative value where the relative holding ratio of the photoelectric conversion element 402 is 100.

  As shown in Table 5, the photoelectric conversion element 401 which is made of a non-curable material and has an intermediate layer containing a conductive polymer having no polymerizable group and a trace amount of fluorinated solvent is photoelectrically compared to the photoelectric conversion element 402. High conversion efficiency and relative retention. Therefore, according to the photoelectric conversion element 401, it can be said that the first and second intermediate layers are formed by a wet method, and the functional deterioration of the photoelectric conversion element is suppressed.

  Therefore, it is understood that the same effect as the organic EL elements of Examples 2 and 3 can be obtained also in the tandem-type photoelectric conversion element.

[Example 5]
<< Preparation of Organic EL Element 501 >>
In the preparation of the organic EL element 201 of Example 2 above, white is similarly produced except that the method of forming the first light emitting layer of the first light emitting unit and the second light emitting layer of the second light emitting unit is changed as follows. A light emitting organic EL element 501 was produced.

(Formation of first light emitting unit-first light emitting layer)
The substrate on which the hole transport layer is formed is fixed to a substrate holder of a commercially available vacuum deposition apparatus, 200 mg of the fluorescent host compound 2 is put in a molybdenum resistance heating boat, and a blue fluorescence emitting dopant compound 3 is put in another molybdenum resistance heating boat. Was placed in a vacuum deposition apparatus. Chemical formulas of the fluorescent host compound 2 and the fluorescent light emitting dopant compound 3 are shown below.

Next, the vacuum chamber is depressurized to 4 × 10 ⁻⁴ Pa, and the heating boat containing the host and the dopant is heated while being energized, and the holes are respectively deposited at a deposition rate of 0.95 nm / sec and 0.05 nm / sec. It co-evaporated on the transport layer and formed the 1st light emitting layer with a layer thickness of 40 nm. In addition, the substrate temperature at the time of vapor deposition was room temperature. In the subsequent formation of the intermediate layer, the substrate on which the first light emitting layer was formed was transferred again to the nitrogen atmosphere without exposure to the air.

(Formation of second light emitting unit-second light emitting layer)
The second light emitting layer material was coated at 5 m / min by die coating on the intermediate layer, naturally dried, and then held at 120 ° C. for 30 minutes to form a second light emitting layer with a layer thickness of 40 nm.

<Second light emitting layer material>
Host compound S-57: 9.26 parts by mass Phosphorescent light emitting dopant D-67: 0.70 parts by mass Phosphorescent light emitting dopant D-74: 0.04 parts by mass Isopropyl acetate: 2000 parts by mass

<< Preparation of organic EL element 502 >>
The same as the preparation of the organic EL element 501 except that 2,2,3,3-tetrafluoro-1-propanol (TFPO) used for forming the first and second intermediate layers was changed to isopropanol (IPA). The organic EL element 502 was fabricated.

<< Evaluation of Organic EL Elements 501 and 502 >>
About the organic EL elements 501 and 502 produced as described above, the rinse-out amount test of the first light emitting layer, the fluorinated solvent content, the light emission efficiency and the light emission lifetime were measured in the same manner as Example 2. The evaluation results are shown in Table 6.
In Table 6, the case where no dominant peak is detected in the mass fragment spectrum corresponding to each fluorinated solvent is indicated as "nd" (not detected). In addition, the light emission efficiency and the light emission life of the organic EL element 501 were determined as relative values based on the light emission efficiency and the light emission life of the organic EL element 502 as 100.

  As shown in Table 6, the organic EL element 501, which is made of a non-curable material and has an intermediate layer containing a conductive polymer having no polymerizable group and a slight amount of fluorinated solvent, emits light in comparison with the organic EL element 502. High efficiency and luminous life. Therefore, according to the organic EL element 501, it can be said that the first to third intermediate layers are formed by a wet method, and the functional deterioration of the organic EL element is suppressed.

  Therefore, it is understood that the same effect as that of Example 2 can be obtained also in the white light emitting type organic EL element using the fluorescent material and the phosphorescent material.

10 Organic thin film laminate 11, 21 Base material 12 First light emitting layer (organic functional layer)
13, 24 Intermediate layer 14 Second light emitting layer (organic functional layer)
20 organic EL element 22 anode 23 first light emitting unit 25 second light emitting unit 26 cathode

Claims (1)

A method of manufacturing an organic electroluminescent device comprising an organic thin film laminate in which a plurality of organic functional layers made of a non-hardenable material are laminated between an anode and a cathode,
Forming an organic functional layer by dissolving in a polar solvent other than a fluorinated solvent and using a solution of the organic functional layer material;
Forming at least one intermediate layer of non-hardenable material;
Have
In the step of forming the at least one intermediate layer, in forming the intermediate layer of any of the at least one intermediate layer, a solution obtained by dissolving a conductive polymer having at least a polymerizable group in a fluorinated solvent is used. The manufacturing method of the organic electroluminescent element characterized by using.

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