JP4797543B2 - Method for manufacturing organic electroluminescent element and organic electroluminescent element - Google Patents

Description

  The present invention relates to a method for producing an organic electroluminescence element (hereinafter, referred to as an organic EL element) that is expected to be widely used as a display such as an information display terminal or a surface emitting light source, and an organic EL element produced by this method. is there.

  In recent years, large and small optical display devices have been used for display applications of information display terminals. Among them, a display device using an organic EL element has been attracting attention as a next-generation display because it is self-luminous and has a high response speed and low power consumption.

  The organic EL element has a simple basic structure in which an organic light emitting medium layer is sandwiched between a first electrode and a second electrode. A voltage is applied between the electrodes, and the light generated when the holes injected from one electrode and the electrons injected from the other electrode recombine in the light emitting layer is used as an image display or light source. is there. The organic light emitting medium layer may be composed of this light emitting layer alone, but may also be composed of a laminated structure in which a light emission auxiliary layer for improving the light emission efficiency is laminated. Examples of the light emission auxiliary layer include a hole transport layer, a hole injection layer, an electron transport layer, and an electron injection layer.

  In order to perform some kind of image display with the organic EL element, it is necessary to adjust on / off of light emission for each pixel. Therefore, it is necessary to provide at least one electrode by patterning. Usually, the first electrode previously formed on the substrate is patterned by, for example, etching. At this time, the step at the end of the first electrode provided in a pattern on the substrate does not cover the light emitting layer or the light emitting auxiliary layer provided on the substrate as it is. Is in contact with the second electrode, causing a short circuit. In order to prevent this short circuit, the end of the first electrode is covered with an insulating material.

  In addition, when the light-emitting layer or light-emitting auxiliary layer formed on the first electrode is formed by using a liquid ink and ejecting ink from a nozzle or by a printing method, the light-emitting layer and the light-emitting auxiliary layer are mixed with each other or conductive. In order to prevent this, a partition wall is formed.

  Therefore, along the respective first electrode shapes, the partition walls are formed in a stripe shape in the case of a passive organic EL element and in a lattice shape in the case of an active organic EL element (see Patent Document 1).

  As described above, the partition wall has a role of preventing the ink held in the partition wall from being mixed with the adjacent pixels, and therefore needs to have a certain height. Usually, it is necessary to be higher than the liquid level of the ink at the time of printing, and in the method of supplying ink from the nozzle, a higher partition wall is required than in the printing method in order to prevent ink splashes from being scattered. Further, in order to prevent the ink from mixing beyond the partition wall, the partition wall is usually provided with lyophobic properties (see, for example, Patent Document 2).

  However, the ink contains a solvent, and when this solvent is removed by drying, the volume of the ink film decreases. For this reason, when the ink is dried to form a light emitting layer, the difference in level between the partition walls and the surface of the organic light emitting medium layer becomes very large. Therefore, when the second electrode is formed on the organic light emitting medium layer, the second electrode may not be formed with a uniform thickness.

  In addition, since the second electrode is generally formed by a vacuum film forming method, it is difficult to form a film on the hydrophobic partition wall, and there is a problem that the second electrode is disconnected on the partition wall. .

In addition, in the top solid sealing required for the so-called top emission structure for extracting light from the top surface of the organic EL element, the step due to the partition prevents uniform sealing, or the adhesive is laminated on the entire surface of the second electrode. Due to the curing shrinkage, stress is applied to the second electrode, the second electrode is likely to be peeled off, and further, the adhesiveness of the adhesive itself is lowered and the sealing substrate is peeled off.
Japanese Patent Laid-Open No. 11-810862 JP-A-11-848339

  It is an object of the present invention to provide an organic EL element that can reliably form an electrode formed on an organic light emitting medium layer and seal the organic EL element, and has no short circuit, and a method for manufacturing the organic EL element.

That is, the invention described in claim 1 includes a substrate, a patterned first electrode provided on the substrate, a lyophilic partition wall covering the end of the first electrode, and the first electrode. Production of an organic electroluminescent device comprising an organic light emitting medium layer provided in a region partitioned by a partition and a second electrode facing the first electrode with the organic light emitting medium layer interposed therebetween In the method
A first electrode forming step of forming a first electrode in a pattern on the substrate;
A partition forming step of forming a lyophilic partition covering the end of the first electrode and a lyophobic partition located on the lyophilic partition;
An organic light emitting medium layer is formed by applying an ink having affinity for the lyophilic partition wall and poor affinity to the lyophilic partition wall in a region defined by the lyophilic partition wall and the lyophobic partition wall. An organic light emitting medium layer forming step;
After the organic light emitting medium layer forming step, a lyophobic partition removing step for removing the lyophobic partition,
A second electrode forming step of forming a second electrode after the lyophobic partition removing step;
It is the manufacturing method of the organic electroluminescent element characterized by comprising.

The invention according to claim 2 is characterized in that the partition forming step includes
Laminating a lyophilic partition wall forming layer on the substrate on which the first electrode is formed;
Laminating a lyophobic partition wall forming layer on the lyophilic partition wall forming layer;
Patterning the lyophobic partition forming layer to form a lyophobic partition; and
2. The method of manufacturing an organic electroluminescence device according to claim 1, wherein the lyophilic partition wall forming layer is patterned by etching using the lyophobic partition wall as an etching mask to form a lyophilic partition wall. .

  The invention according to claim 3 is the method for producing an organic electroluminescence element according to claim 1 or 2, wherein the organic light emitting medium layer forming step is based on a printing method.

  The invention according to claim 4 is the method for producing an organic electroluminescent element according to claim 3, wherein the printing method is a relief printing method or a method of ejecting ink from a nozzle.

The invention described in claim 5 is the method for producing an organic electroluminescent element according to any one of claims 1 to 4, wherein the lyophilic partition is made of an inorganic material.

  The invention described in claim 6 is the method for producing an organic electroluminescent element according to any one of claims 1 to 5, wherein the lyophobic partition is made of an organic material.

The invention according to claim 7 includes a substrate, a patterned first electrode provided on the substrate, a lyophilic partition covering the end of the first electrode, and the first electrode. In an organic electroluminescence device comprising an organic light emitting medium layer provided in a region partitioned by a partition wall and a second electrode facing the first electrode with the organic light emitting medium layer interposed therebetween,
The organic electroluminescence device is characterized in that the upper surface of the lyophilic partition wall and the upper surface of the organic light emitting medium layer have the same height.

  According to the present invention, in the organic luminescent medium layer forming step, the lyophobic barrier ribs stacked on the lyophilic barrier ribs have a sufficient height, so that the applied organic luminescent medium layer mixes across the barrier ribs. There is nothing. In addition, the lyophobic partition is removed after the organic light emitting medium layer forming step, and the partition is low and lyophilic, so there is no disconnection of the electrode, and the organic layer is reliably sealed and highly reliable. An EL element can be obtained.

  The present invention will be described below with reference to the drawings.

(substrate)
As the substrate 1 according to the present invention, any substrate can be used as long as it is an insulating substrate. In the case of a bottom emission element that emits light from the substrate side, it is necessary to use a transparent substrate.

  For example, a glass substrate or a quartz substrate can be used. Further, it may be a plastic film or sheet such as polypropylene, polyethersulfone, polycarbonate, cycloolefin polymer, polyarylate, polyamide, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate. These plastic films and sheets laminated with a metal oxide thin film, a metal fluoride thin film, a metal nitride thin film, a metal oxynitride thin film, or a polymer resin film may be used as a substrate. Examples of the metal oxide thin film include silicon oxide and aluminum oxide. Examples of the metal fluoride thin film include aluminum fluoride and magnesium fluoride. Examples of the metal nitride thin film include silicon nitride and aluminum nitride. Examples of the polymer resin film include acrylic resin, epoxy resin, silicone resin, and polyester resin.

  In the case of a top emission element, an opaque substrate can also be used. For example, a metal foil such as aluminum or stainless steel, a metal sheet, a metal plate, or the like. Moreover, it is also possible to use what laminated | stacked metal thin films, such as aluminum, copper, nickel, stainless steel, on the said plastic film and sheet | seat.

  In addition, it is more preferable to reduce the moisture adsorbed on the inside or the surface of the substrate as much as possible by performing a heat treatment on these substrates in advance. Moreover, it is preferable to use after performing surface treatments, such as an ultrasonic cleaning process, a corona discharge process, a plasma process, and a UV ozone process, in order to improve adhesiveness according to the material laminated | stacked on a board | substrate.

  Further, a thin film transistor (TFT) may be formed on these to form a driving substrate. The TFT material may be an organic TFT such as polythiophene, polyaniline, copper phthalocyanine or perylene derivative, or may be amorphous silicon or polysilicon TFT. A color filter layer, a light scattering layer, a light deflection layer, or the like may be provided as a substrate.

(First electrode formation process)
Next, the first electrode 2 is formed on the substrate 1 (FIG. 1).

  The first electrode 2 applies a voltage to the organic light emitting medium layer 4 together with the second electrode 5. In order to apply a voltage to each pixel, the first electrode 2 needs to be configured in a pattern. For example, when the second electrode 5 is formed uniformly on the entire surface, the first electrode 2 must be formed in a pixel pattern. Moreover, when the 2nd electrode 5 has a stripe pattern, the 1st electrode 2 can be comprised in the stripe pattern which cross | intersects this, and the intersection part can be made into a pixel.

  Either the first electrode 2 or the second electrode 5 may be an anode. When the first electrode 2 is an anode, the second electrode 5 is a cathode. The opposite is also possible. In the case of a bottom emission element, the first electrode 2 needs to be transparent. In the case of a top emission element, the second electrode 5 needs to be transparent.

  The case of the bottom emission element will be described as an example. As the material of the first electrode 2, a metal composite oxide such as ITO (indium tin composite oxide), indium zinc composite oxide, zinc aluminum composite oxide, or the like can be used. . A vacuum film forming method can be used as the film forming method. For example, resistance heating vapor deposition, electron beam vapor deposition, reactive vapor deposition, ion plating, and sputtering. Then, a photoresist can be applied to the vacuum-formed metal oxide film, exposed and developed, and wet etched or dry etched to be processed into a pattern.

  Further, as the material for the first electrode, a fine particle dispersion film in which the metal oxide fine particles are dispersed in an epoxy resin, an acrylic resin or the like can be used. As the film forming method, a wet film forming method such as a gravure printing method or a screen printing method can be used. In this case, a patterned film can be formed.

(Partition forming process)
Next, a partition that covers the end of the first electrode 2 is formed. The partition wall has a two-layer structure of a lyophilic partition wall 31 and a lyophobic partition wall 32, and partitions the pixels. As shown in the figure, the lyophilic partition wall 31 is larger than the lyophobic partition wall 32.

  As the material of the lyophilic partition wall 31, a material excellent in affinity with the ink constituting the organic light emitting medium layer 4 and the second electrode 5 can be preferably used. Generally, it is a hydrophilic inorganic material. For example, inorganic oxides and inorganic nitrides. Examples of the inorganic oxide include silicon oxide and aluminum oxide. Examples of the inorganic nitride include silicon nitride and silicon carbonitride. The thickness needs to be the same as the thickness of the first electrode 2 plus the thickness of the organic light emitting medium layer 4. Generally, it is 100 to 500 nm.

This lyophilic partition wall can be patterned into a partition wall pattern by forming a film (lyophilic partition wall forming layer) 31 on the first electrode and then etching. As a method for forming the lyophilic partition wall forming layer 31, the above-described vacuum film forming method can be used. At the time of etching, it can be processed into a pattern by etching using a lyophobic partition described later as an etching mask. The lyophilicity can be evaluated by a contact angle, preferably a contact angle of 20 degrees or less, more preferably 10 degrees or less.

Next, as a material of the lyophobic partition wall 32, an organic material having poor affinity with the applied ink can be preferably used. Preferably, it is a photosensitive material. Examples of the photosensitive material include a photosensitive material containing a monomer or an oligomer and a photopolymerization initiator that polymerizes the monomer or oligomer in a resin binder. Then, this photosensitive material is applied onto the lyophilic partition wall forming layer 31 to provide a film (lyophobic partition wall forming layer) (FIG. 2), exposed and developed to be processed into a partition wall pattern, and then fluorine. The lyophobic property can be enhanced by treatment with a plasma of a system gas (FIG. 3). As the fluorine-based gas, CF ₄ , SF ₆ , CHF ₃ or the like can be used.

  Further, as the photosensitive material, a photosensitive material containing a monomer or oligomer, a photopolymerization initiator for polymerizing the monomer or oligomer, and a lyophobic agent on the resin binder is formed on the lyophilic partition wall forming layer 31. The coating (liquid-phobic partition wall forming layer) is provided by coating (FIG. 2), and exposed and developed to form partition walls (FIG. 3). In addition, the contact angle of the lyophobic partition is 50 degrees or more, preferably 100 degrees or more.

  As this binder resin, a resin containing an amino group, an amide group, a carboxyl group or a hydroxyl group can be preferably used. Specifically, a cresol-novolak resin, a polyvinylphenol resin, an acrylic resin, a methacrylic resin, and the like can be given.

  As the monomer or oligomer, a monomer or oligomer having a vinyl group or an allyl group, or a molecule having a vinyl group or an allyl group at the terminal or side chain can be used. Specifically, (meth) acrylic acid and salts thereof, (meth) acrylic acid esters, (meth) acrylamides, maleic anhydride, maleic acid esters, itaconic acid esters, styrenes, vinyl ethers, vinyl esters, Mention may be made of N-vinyl heterocycles, allyl ethers, allyl esters, and derivatives thereof. Examples of suitable compounds include relatively low molecular weight polyfunctional acrylates such as pentaerythritol triacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol penta and hexaacrylate. be able to. These monomers may be used alone or in combination of two or more. The amount of the monomer can be in the range of 1 to 200 parts by weight, preferably 50 to 150 parts by weight with respect to 100 parts by weight of the binder resin.

Examples of the photopolymerization initiator include benzophenone compounds such as benzophenone, 4,4′-bis (dimethylamino) benzophenone, and 4,4′-bis (diethylamino) benzophenone. In addition, as photopolymerization initiators, 1-hydroxycyclohexyl acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one An acetophenone derivative such as can also be used. Further, thioxanthone derivatives such as thioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, and 2-chlorothioxanthone may be used. Moreover, anthraquinone derivatives such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, and chloroanthraquinone may be used. In addition, benzoin ether derivatives such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether can also be used. Further, acylphosphine derivatives such as phenylbis- (2,4,6-trimethylbenzoyl) -phosphine oxide, 2- (o-chlorophenyl) -4,5-bis (4′-methylphenyl) imidazolyl dimer Lophine isomers such as N-phenylglycine, organic azides such as 4,4′-diazidochalcone, 3,3 ′, 4,4′-tetra (t
ert-butylperoxycarboxy) benzophenone, quinonediazide group-containing compounds, and the like.

  As the lyophobic agent, a compound having a fluoroalkyl group can be used. For example, polyvinyl fluoride, polyvinylidene fluoride, polytrifluoride ethylene, or a copolymer thereof. The lyophobic agent is preferably 0.01% by weight to 10% by weight with respect to the photosensitive material.

  For example, an ultrahigh pressure mercury lamp can be used for exposure of the film obtained by applying the photosensitive material. As the developer, an aqueous sodium carbonate solution can be used. In addition, by performing baking after exposure / development, the lyophobic agent can be exuded on the surface of the lyophobic partition wall 32 to improve the lyophobic property of the lyophobic partition wall 32.

  Next, patterning is performed by etching the lyophilic partition wall forming layer 31 using the lyophobic partition wall 32 thus formed as an etching mask (FIG. 4). When the lyophilic partition wall forming layer 31 is made of silicon oxide, wet etching can be performed using hydrofluoric acid as an etchant. Moreover, you may process by dry etching. The resulting lyophilic partition wall 31 and lyophobic partition wall 32 have a structure in which both are aligned and stacked.

  The lyophilic partition wall 31 formed by patterning needs to be a pattern that covers the end portion of the first electrode 2 and exposes the first electrode 2 of the pixel portion. The overlapping length of the first electrode 2 and the lyophilic partition wall 31 is arbitrary, but it must be long enough to prevent a short circuit between the second electrode 5 and the first electrode 2. For example, it is 0.1 μm or more. As shown in FIG. 4, since the etching proceeds in a reverse taper shape, the tapered lyophilic partition wall 31 covering the end portion of the first electrode 2 is controlled by controlling the etching speed and time. It is possible to form. In addition, the lyophilicity can be enhanced by performing oxygen plasma treatment on the lyophilic partition after the etching.

(Organic light emitting medium layer 4 formation process)
Next, ink is applied to the area partitioned by the lyophilic partition wall 31 and the lyophobic partition wall 32 to form the organic light emitting medium layer 4 (FIG. 5).

  The organic light emitting medium layer 4 includes a light emitting layer that emits light when a voltage is applied. The light emitting layer may be composed of a single layer, or may be composed of a laminated structure in which a light emitting auxiliary layer for improving light emission efficiency is laminated in addition to the light emitting layer. Examples of the light emission auxiliary layer include a hole transport layer, a hole injection layer, an electron transport layer, and an electron injection layer.

  The light emitting layer and the light emission auxiliary layer are preferably applied by making all the material of these layers into ink, but any one of the layers may be applied as ink.

The main component of the light emitting layer is a light emitting material that emits light when a voltage is applied. Such luminescent materials include 9,10-diarylanthracene derivatives, pyrene, coronene, perylene, rubrene, 1,1,4,4-tetraphenylbutadiene, tris (8-quinolinolato) aluminum complex, tris (4-methyl). -8-quinolinolato) aluminum complex, bis (8-quinolinolato) zinc complex, tris (4-methyl-5-trifluoromethyl-8-quinolinolato) aluminum complex, tris (4-methyl-5-cyano-8-quinolinolato) Aluminum complex, bis (2-methyl-5-trifluoromethyl-8-quinolinolato) [4- (4-cyanophenyl) phenolate] aluminum complex, bis (2-methyl-5-cyano-8-quinolinolato) [4- (4-Cyanophenyl) phenolate] Aluminum , Tris (8-quinolinolato) scandium complex, bis [8- (para-tosyl) aminoquinoline] zinc complex and cadmium complex, 1,2,3,4-tetraphenylcyclopentadiene, pentaphenylcyclopentadiene, poly-2 , 5-diheptyloxy-para-phenylene vinylene, coumarin phosphor, perylene phosphor, pyran phosphor, anthrone phosphor, porphyrin phosphor, quinacridone phosphor, N, N′-dialkyl-substituted quinacridone Low molecular light emitting materials such as phosphorescent light emitters such as Ir complexes, such as phosphors based on phosphors, naphthalimide phosphors, N, N′-diaryl-substituted pyrrolopyrrole phosphors can be used. Further, it may be a polymer light emitting material such as polyfluorene, polyparaphenylene vinylene, polythiophene, or polyspiro. In addition, a material obtained by dispersing or copolymerizing the low molecular weight material in these high molecular materials or other existing light emitting materials can be used.

  In addition, as a material for the hole transport layer, metal phthalocyanines such as copper phthalocyanine and tetra (t-butyl) copper phthalocyanine and metal-free phthalocyanines, quinacridone compounds, 1,1-bis (4-di-p-tolylamino) Phenyl) cyclohexane, N, N′-diphenyl-N, N′-bis (3-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N′-di (1-naphthyl)- Examples thereof include aromatic amine-based low-molecular hole injection transport materials such as N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine. Further, a polymer hole transport material such as polyaniline, polythiophene, polyvinyl carbazole, a mixture of poly (3,4-ethylenedioxythiophene) and polystyrenesulfonic acid may be used. A polythiophene oligomer material can also be used.

  As the electron transport layer, 2- (4-bifinylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1, 3,4-oxadiazole, oxadiazole derivatives, bis (10-hydroxybenzo [h] quinolinolato) beryllium complexes, triazole compounds, and the like can be used.

  An ink can be formed by adding a solvent and necessary additives to the materials of these layers. As the solvent, it is necessary to use a solvent having affinity for the lyophilic partition wall 31 and poor affinity for the lyophobic partition wall 32. When the lyophilic partition wall 31 is composed of an inorganic material and the lyophobic partition wall 32 is composed of an organic material containing a lyophobic agent, examples of the solvent include dichloromethane, dichloroethane, chloroform, acetone, cyclohexanone, ethyl acetate, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-ethylethoxyacetate, 2-butoxyethyl acetate, 2-methoxyethyl ether, 2-ethoxyethyl ether, 2- (2-ethoxyethoxy) ethanol, 2 -(2-butoxyethoxy) ethanol, 2- (2'ethoxyethoxy) ethyl acetate, 2- (2-butoxyethoxy) ethyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethyl Glycol dimethyl ether, tetrahydrofuran and the like can be used. Since the ink constituted using these solvents has affinity for the lyophilic partition wall 31, it spreads uniformly in the region to form a film having a uniform film thickness. Further, since this ink has poor affinity for the lyophobic partition wall 32, it is blocked by the lyophobic partition wall 32 and does not protrude beyond the lyophobic partition wall 32 into an adjacent region.

  This ink can be selectively applied to the area by a printing method. For this reason, it is possible to produce an organic EL element capable of color display by printing a light emitting layer that emits light in different colors on each pixel. As a printing method, for example, a relief printing method can be used. This is a relief printing method using a flexographic plate. Further, it is also possible to use a method in which the ink is changed to particles and the particle ink is ejected from a nozzle and adhered to the region. As an ink discharge device used in this method, a piezo conversion method and a heat conversion method are known, but a piezo conversion ink discharge device can be preferably applied. The ink particleization frequency may be 5 to 100 KHz, and the nozzle diameter may be 5 to 80 μm.

  In the ink film printed in this way, the solvent is removed by the drying process, and the film thickness is reduced by the solvent removal. The film thickness after drying is the same as that of the upper surface of the lyophilic partition wall 31, that is, flush with the upper surface of the lyophilic partition wall 31, whether the light emitting layer is composed of a single layer or a multilayer structure. It is necessary to be a thickness. 1000 nm or less, preferably 50 to 300 nm.

  Since the first electrode 2 is completely covered by the organic light emitting medium layer 4 and the lyophilic partition wall 31 formed with a uniform thickness in this region, the second electrode 5 provided thereon is provided. And the first electrode 2 can be prevented from being short-circuited.

(Liquid barrier 32 removal step)
Next, the lyophobic partition wall 32 is removed (FIG. 6). For example, lift-off method
Can be removed. Alternatively, the lyophobic partition wall 32 may be dissolved and removed by applying a solvent that does not dissolve the organic light emitting medium layer 4. An example of such a solvent is acetone.

(Second electrode 5 forming step)
As described above, the second electrode 5 applies a voltage to the organic light emitting medium layer 4 together with the first electrode 2. In the case of a bottom emission element, an opaque element can be used as the second electrode 5. As a material for the second electrode 5, a substance having a high electron injection efficiency into the organic light emitting medium layer 4 is used. Specifically, a single metal such as Mg, Al, or Yb is used, or a compound such as Li, oxidized Li, or LiF is sandwiched by about 1 nm at the interface in contact with the light-emitting medium to improve stability and conductivity. May be used in a stacked manner. Alternatively, in order to achieve both electron injection efficiency and stability, an alloy of a metal having a low work function and a stable metal may be used. Examples of the metal having a low work function include Li, Mg, Ca, Sr, La, Ce, Er, Eu, Sc, Y, and Yb. Examples of the stable metal include Ag, Al, and Cu. Specifically, it is an alloy such as MgAg, AlLi, or CuLi.

  The second electrode 5 can be formed on the surface of the organic light emitting medium layer 4 and the lyophilic partition wall 31 using a vacuum film forming method. Examples of the vacuum film forming method include a resistance heating vapor deposition method, an electron beam vapor deposition method, a reactive vapor deposition method, an ion plating method, and a sputtering method. At this time, since the organic light emitting medium layer and the lyophilic partition are formed flush with each other, the formed second electrode does not break.

  If patterning of the second electrode 5 is necessary, a photoresist is applied on the second electrode 5 and exposed / developed, and processed into a pattern by wet etching or dry etching. (FIG. 7).

(Sealing process)
Next, an organic EL element can be sealed by adhering a sealing substrate 7 on the second electrode 5 via an adhesive 6 (FIG. 8). As the sealing substrate 7, ceramics, glass, quartz, metal foil, moisture resistant film, or the like can be used. Examples of ceramics include alumina, silicon nitride, and boron nitride. Examples of the glass include alkali-free glass and alkali glass. Examples of the metal foil include an aluminum moisture resistant film. As the moisture resistant film, a film obtained by forming a thin film of silicon oxide on both sides of a plastic substrate can be used.

As the adhesive 6, a thermoplastic resin, a photocurable adhesive resin, a thermosetting adhesive resin, a two-component curable adhesive resin, or the like can be used. Examples of the thermoplastic resin include vinyl resin, polyamide, and synthetic rubber. Among these, examples of the vinyl resin include acrylic resins such as ethylene ethyl acrylate, ethylene vinyl acetate, and the like. Examples of the photocurable adhesive resin include an epoxy resin, an acrylic resin, and a silicone resin.

<Example 1>
First, the partition layer 3 is formed so as to cover the end of the ITO film 2 formed on the glass substrate 1. As the partition, a two-layer structure having a lyophilic partition 31 made of a silicon carbonitride film and a lyophobic partition 32 made of polyimide resin is used.

First, a 500 nm-thick silicon carbonitride film was formed on the ITO film 2 by the CVD method to form a lyophilic partition wall forming layer 31. Thereafter, a liquid-repellent polyimide resist material was applied to a thickness of 1 μm using a slit coating method to form a lyophobic partition wall forming layer 32. Then, the lyophobic barrier rib formation layer 32 was patterned using a photolithography method. Thereafter, the lyophilic partition wall formation layer 31 is etched by an etching method using the lyophobic partition wall 32 as a mask, and then the silicon carbonitride film is treated with oxygen plasma to improve the lyophilic property, followed by CF ₄ plasma. The lyophobic partition wall 32 was treated to increase the lyophobic property. The lyophilic partition wall 31 was a pattern that exposed the ITO film 2 in the pixel portion and covered the end portion thereof.

  Next, a polymer hole transport layer 41 (film thickness after drying 50 nm) and a polymer light emitting layer 42 (film thickness after drying 80 nm) as the organic light emitting medium layer 4 are formed in the openings of the partition walls 31 and 32. It was formed using a relief printing method.

  Here, as a material for the polymer hole transport layer, an ink in which a polythiophene derivative (PEDOT) is dispersed in water, and as a material for the polymer light emitting layer, a polyfluorene material is dissolved in an aromatic solvent such as toluene / xylene. Ink was used.

  Next, the lyophilic partition wall 31 was exposed by peeling off the lyophobic partition wall 32.

  Next, Ba (film thickness 5 nm) and Al (film thickness 100 nm) were formed in this order as the cathode 5 by vapor deposition.

  Finally, a thermosetting epoxy adhesive was bonded as the adhesive layer 6, and glass was bonded as the sealing substrate 7.

  The produced organic EL device showed good light emission without disconnection or the like.

<Example 2>
In Example 1, as a result of producing the hole transport layer and the light emitting layer by the ink jet method, good light emission was obtained without disconnection or the like.

<Comparative Example 1>
In Example 1, the cathode layer 5, the adhesive layer 6, and the sealing substrate 7 were formed without peeling off the lyophobic partition wall 32.

  In the produced organic EL device, disconnection of the cathode and peeling of the adhesive layer occurred on the lyophobic partition wall 32, and light emission failure occurred.

Sectional drawing which shows the 1st electrode formation process of this invention. Sectional drawing which shows the partition formation process of this invention. Sectional drawing which shows the partition formation process of this invention. Sectional drawing which shows the partition formation process of this invention. Sectional drawing which shows the organic luminescent medium layer formation process of this invention. Sectional drawing which shows the lyophobic partition removal process of this invention. Sectional drawing which shows the 2nd electrode formation process of this invention. Sectional drawing which shows the sealing process of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 First electrode 3 Partition 31 Hydrophilic partition layer 32 Hydrophobic partition layer 4 Organic luminescent medium layer 5 Second electrode 6 Adhesive layer 7 Sealing substrate

Claims (6)

A substrate, a patterned first electrode provided on the substrate, a lyophilic partition that covers the end of the first electrode, and a region on the first electrode that is partitioned by the partition In the method for manufacturing an organic electroluminescent element, comprising: an organic light emitting medium layer provided on the substrate; and a second electrode facing the first electrode across the organic light emitting medium layer. The first electrode forming step for forming the electrode, the lyophilic partition that covers the end of the first electrode, and the partition forming step for forming the lyophobic partition located on the lyophilic partition And applying an ink having affinity for the lyophilic partition wall and poor affinity to the lyophobic partition wall in a region defined by the lyophilic partition wall and the lyophobic partition wall. After the organic light emitting medium layer forming step to be formed and the organic light emitting medium layer forming step A lyophobic partition wall removing step of removing the lyophobic partition wall, after the lyophobic partition wall removing step, and a second electrode forming step of forming a second electrode, comprising,
The partition formation step includes a step of laminating a lyophilic partition wall formation layer on a substrate on which a first electrode is formed, a step of laminating a lyophobic partition wall formation layer on the lyophilic partition wall formation layer, A step of patterning the lyophobic partition wall forming layer to form a lyophobic partition wall, and a step of patterning the lyophilic partition wall forming layer by etching using the lyophobic partition wall as an etching mask to form a lyophilic partition wall. method of manufacturing an organic electroluminescent device, characterized in that. The organic light emitting medium layer forming step, the method of manufacturing the organic electroluminescent device according to claim 1, wherein the by the printing method. 3. The method of manufacturing an organic electroluminescence element according to claim 2, wherein the printing method is a relief printing method or a method of discharging ink from a nozzle. The method for producing an organic electroluminescent element according to any one of claims 1 to 3 , wherein the lyophilic partition is made of an inorganic material. Method of manufacturing an organic electroluminescent device according to any one of claims 1 to 4, wherein the lyophobic partition wall is characterized by being composed of an organic material.   A substrate, a patterned first electrode provided on the substrate, a lyophilic partition that covers the end of the first electrode, and a region on the first electrode that is partitioned by the partition An organic electroluminescent device comprising: an organic light emitting medium layer provided on the second electrode; and a second electrode facing the first electrode with the organic light emitting medium layer interposed therebetween, wherein the upper surface of the lyophilic partition and the organic light emitting medium An organic electroluminescence device characterized in that the upper surface of the layer has the same height.

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