JP2010067355A - Organic el element panel and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL element panel which is formed by pasting together a support substrate and a sealing substrate without bubbles when an organic EL element is sealed, is made thin and lightweight, and has high adhesive property and long life. <P>SOLUTION: The organic EL element panel has: a support substrate; an organic EL element composed of an anode formed on the support substrate, an organic light-emitting medium layer and a cathode; a first sheet-like adhesive formed on the organic EL element; the sealing substrate to seal the organic EL element; and a second sheet-like adhesive which is pinched between the first sheet-like adhesive and the sealing substrate, and formed separately from the first sheet-like adhesive. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an organic EL element panel and a manufacturing method thereof, and in particular, an organic EL element panel in which a support substrate on which an organic EL element is formed and a sealing substrate for sealing the organic EL element are bonded together with an adhesive, and the same It relates to a manufacturing method.

  As a light-emitting electronic display device, there is an electroluminescence display (ELD). Examples of the constituent elements of ELD include inorganic EL elements and organic EL elements. Inorganic EL elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements. An organic EL device has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and injects electrons and holes into the light emitting layer to recombine excitons. It is an element that emits light by utilizing the emission of light (fluorescence / phosphorescence) when this exciton is deactivated, and can emit light at a voltage of several volts to several tens of volts. Therefore, it has a wide viewing angle, high visibility, and since it is a thin-film type completely solid element, it has attracted attention from the viewpoints of space saving and portability.

  However, in organic EL elements for practical use, one of the major problems is the problem of performance degradation when in contact with humidity or air, achieving high durability and long life of the organic EL elements. Technology is highly desired.

  On the other hand, Patent Document 1 discloses an organic EL panel using a sealing film having a barrier property capable of forming a thin organic EL element (see Patent Document 1). In Patent Document 1, the film is bonded to a moisture-proof film through an adhesive provided in a frame shape on the outer periphery of the organic EL element region. Patent Document 2 discloses a technique in which a sealing substrate including a plastic substrate is bonded to each other via a sheet-like adhesive provided so as to cover the entire surface of the organic EL element region (Patent Document 2). 2). However, when different materials are used for the element substrate on which the organic EL element is formed and the moisture-proof film as in Patent Documents 1 and 2, an organic EL element substrate is used with one type of adhesive due to the difference in thermal shrinkage. It is a problem that either the adhesive interface or the moisture-proof film and the adhesive interface is easily peeled off, and moisture and oxygen from the outside are permeated to cause deterioration of the organic EL element.

  Therefore, in order to improve the deterioration of the organic EL element due to the intrusion of moisture, oxygen, etc. from the outside, Patent Document 3 describes organic EL element / resin layer / liquid adhesive layer / sealing substrate (plastic substrate). (See Patent Document 3). Patent Document 3 is a method in which a liquid adhesive is applied on a substrate of an organic EL element on which a resin layer is formed with a dropping device, and a sealing substrate is bonded by its own weight. However, with this method, it is difficult to form a liquid adhesive with a thin film and uniform film thickness. Therefore, since it is a thick film, it is difficult to realize low moisture permeability, and the organic EL element is deteriorated at an early stage. In addition, when a spacer is provided in the liquid adhesive for the purpose of controlling the film thickness, there is a problem that the spacer sinks at the time of bonding, and the organic EL element is damaged and cannot be used for top emission due to light scattering by the spacer.

On the other hand, Patent Document 4 discloses a technique composed of an organic EL element / sheet adhesive / liquid adhesive / sealing substrate (including a plastic substrate). Patent Document 4 is a method in which an organic EL element substrate on which a sheet-like adhesive is attached and a sealing substrate on which a liquid adhesive is formed are attached. When a flexible film such as a plastic substrate is used for the sealing substrate, the flexible film is bonded while being bent so that bubbles do not enter. . As a result, the adhesive spreads even outside the region determined at the time of bonding, and the thickness of the adhesive differs between the front and rear of the bonding region.
JP 2007-59311 A JP 2006-179352 A JP 2007-5107 A JP 2007-80711 A

  The present invention provides an organic EL element panel that can be bonded without bubbles when the organic EL element is sealed, has high adhesion, is thin and light, and has a long life, and a method for manufacturing the same. It is.

  The invention according to claim 1 of the present invention includes a support substrate, an organic EL element comprising an anode formed on the support substrate, an organic light emitting medium layer and a cathode, and a first sheet formed on the organic EL element. An adhesive, a sealing substrate for sealing the organic EL element, and a second sheet formed separately from the first sheet-shaped adhesive sandwiched between the first sheet-shaped adhesive and the sealing substrate. It is set as the organic EL element panel characterized by having this sheet-like adhesive.

  The invention according to claim 2 of the present invention is the organic EL element panel according to claim 1, wherein the organic EL element is further covered with a protective film having a visible transmittance of 75% or more. Is.

In the invention according to claim 3 of the present invention, the support substrate is different from the sealing substrate and the base material, the water vapor permeability is 0.01 g / m ² · day or less, and the oxygen permeability is 10 ⁻³ ml / m ² · 3. The organic EL element panel according to claim 1, which has a day barrier property and is colorless and transparent.

In the invention according to claim 4 of the present invention, the sealing substrate is a flexible material having a barrier property such that a water vapor permeability is 0.01 g / m ² · day or less and an oxygen permeability is 10 ⁻³ ml / m ² · day. The organic EL element panel according to any one of claims 1 to 3, wherein the organic EL element panel has a visible transmittance of 75% or more.

  The invention according to claim 5 of the present invention is the organic EL element panel according to any one of claims 1 to 4, wherein the light extraction direction is top emission or bottom emission. It is a panel.

  In the invention according to claim 6 of the present invention, an anode, an organic issue medium layer, and a cathode are sequentially laminated on a support substrate to form an organic EL element, and a first sheet-like adhesive is formed on the support substrate side, An organic EL element panel, wherein a second sheet-like adhesive is formed on a sealing substrate, and the first sheet-like adhesive and the second sheet-like adhesive are bonded and cured so as to face each other. This is a manufacturing method.

  The invention according to claim 7 of the present invention is the organic EL element panel according to claim 6, wherein the organic EL element further has a protective film, and the visible transmittance of the protective film is 75% or more. This is a manufacturing method.

In the invention according to claim 8 of the present invention, the support substrate is different from the sealing substrate and the base material, the water vapor transmission rate is 0.01 g / m ² · day or less, and the oxygen transmission rate is 10 ⁻³ ml / m ² · 8. The method for producing an organic EL element panel according to claim 6, which has a day barrier property and is colorless and transparent.

In the invention according to claim 9 of the present invention, the sealing substrate is a flexible material having a barrier property such that a water vapor permeability is 0.01 g / m ² · day or less and an oxygen permeability is 10 ⁻³ ml / m ² · day. The organic EL element panel manufacturing method according to any one of claims 6 to 8, wherein the organic EL element panel has a visible transmittance of 75% or more.

  ADVANTAGE OF THE INVENTION According to this invention, when sealing to an organic EL element, an organic EL element panel which can be bonded without bubbles, has high adhesiveness, is thin and lightweight, and has a long life is provided. can do.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. Note that the drawings referred to in the following description of the embodiments are for explaining the configuration of the present invention, and the size, thickness, dimensions, and the like of each part shown in the drawings are different from the actual ones. The present invention is not limited to these.

  FIG. 1 is a schematic cross-sectional view showing an organic EL panel 100 according to an embodiment of the present invention. As shown in FIG. 1, an organic EL panel 100 according to an embodiment of the present invention includes a support substrate 10, an organic EL element 20 including a protective film 14 formed on the support substrate 10, and the entire surface of the organic EL element 20. The sheet-like adhesive 41 formed so as to cover and the sheet-like adhesive 42 formed on the sealing substrate 50 are bonded together. Hereinafter, the structure of the organic EL element 20 shown in FIG. 1 will be described with reference to FIG.

[Organic EL element 20]
FIG. 2 is a schematic cross-sectional view showing the organic EL element 20 according to the embodiment of the present invention. As shown in FIG. 2, the organic EL element 20 according to the embodiment of the present invention includes a support substrate 10, an anode 11, an organic light emitting medium layer 12, a cathode 13, and a protective film 14. Here, FIG. 2 shows only one light emitting portion (corresponding to a pixel in the case of monochromatic display and a subpixel in the case of multicolor display), but it may have a plurality of light emitting portions.

  As shown in FIG. 1, the support substrate 10 according to the present embodiment is made of a transparent material having transparency, and glass, quartz, or the like can be suitably used. Also, a resin film having a rigidity of 0.3 mm or more can be suitably used. Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and 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 Polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylates, trade name “Arton (registered trademark)” (manufactured by JSR) or trade name “Apel (registered trademark)” ”(Made by Mitsui Chemicals) can be used. Furthermore, a thin film transistor (TFT) may be formed on the support base material 10 as necessary, and used as a driving substrate. As the TFT material, organic TFTs such as polythiophene, polyaniline, copper phthalocyanine, and perylene derivatives may be used, and amorphous silicon TFTs and polysilicon TFTs may be used.

When a glass substrate is used as the support substrate 10, a film thickness of 0.3 mm to 1.8 mm, preferably 0.5 mm to 0.7 mm can be used. Moreover, when using a resin film as the support substrate 10, it has an inorganic and organic barrier film on the surface of the resin film, and the water vapor permeability measured by a method according to JIS K 7129-1992 is 0.01 g. / M ² · day · atm or less of the barrier film is preferable. Further, the oxygen permeability is 10 ⁻³ ml / m ² / day or less, and the water vapor permeability is 10 ⁻⁵ g / m ² / day or less. It is preferable that The organic EL panel 100 having a long life can be obtained by using the support substrate 10 having a barrier property with an oxygen permeability of 10 ⁻³ ml / m ² / day or less and a water vapor permeability of 10 ⁻⁵ g / m ² / day or less. Can be produced. Moreover, since the support substrate 10 is colorless and transparent, light emitted from the support substrate 10 side can be extracted (bottom emission). Although there is no restriction | limiting in particular in the film thickness in the case of using a resin film as the support substrate 10, It should just be 10 micrometers or more, and it is desirable that it is 30 micrometers-1.1 mm desirably.

Next, the anode 11 is formed on the support substrate 10. As shown in FIG. 1, as the anode 11 according to the present embodiment, a metal, an alloy, an electrically conductive compound, and a mixture thereof having a high work function (4 eV or more) can be preferably used. Examples of the material of the anode 11 include conductive transparent materials such as metals such as Au, CuI, indium tin oxide (ITO), SnO ₂ , and ZnO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. The anode 11 may be formed by forming a thin film from these materials by a vacuum deposition method or a sputtering method, and forming a desired pattern by a photolithography method. Alternatively, when pattern accuracy is not required so much (in the case of about 100 μm or more), the pattern of the anode 11 may be formed through a mask having a desired shape when performing vacuum deposition or sputtering. Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used. When light is extracted from the anode 11 (bottom emission), it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode 11 is preferably several hundred Ω / □ or less. The film thickness of the anode 11 depends on the material used, but is usually selected in the range of 10 nm to 1000 nm, preferably 10 nm to 200 nm.

  Next, the organic light emitting medium layer 12 is formed on the anode 11. The organic light emitting medium layer 12 in the present embodiment can be formed of a single layer film including a light emitting layer or a multilayer film. Examples of the configuration in the case of forming a multilayer film include a hole transport layer, an electron transporting light emitting layer or a hole transporting light emitting layer, a two-layer structure comprising an electron transport layer, a hole transport layer, a light emitting layer, and an electron transport layer. There is a three-layer structure consisting of Furthermore, if necessary, the hole or electron injection function and the hole or electron transport function can be separated, or a layer that blocks the transport of holes or electrons can be inserted to form a multilayer. More preferred. In the present embodiment, a three-layer structure including a hole transport layer, a light emitting layer, and an electron transport layer is used as the organic light emitting medium layer 12.

  Examples of the material for the hole transport layer include metal phthalocyanines and metal-free phthalocyanines such as copper phthalocyanine and tetra (t-butyl) copper phthalocyanine, 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)- Aromatic amine-based low molecular hole injection and transport materials such as N, N′-diphenyl-1,1′-biphenyl-4,4′-diamine, polyaniline, polythiophene, polyvinylcarbazole, poly (3,4-ethylenediene) Oxythiophene) and polystyrene sulfonic acid mixtures such as polymer hole transport layer materials, polythiophene oligomer materials, etc. can be used There is not limited thereto in the present invention.

  As the material for the light emitting layer, 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 complex, Lis (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 fluorescence , Naphthalimide-based phosphors, N, N′-diaryl-substituted pyrrolopyrrole-based phosphors, phosphorescent phosphors such as Ir complexes, and other low-molecular light-emitting materials, polyfluorene, polyparaphenylene vinylene, polythiophene, polyspiro High molecular materials such as Or it can be used copolymerized materials but are not limited to these.

  As a material for the electron transport layer, 2- (4-bifinylyl) -5- (4-t-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, but the present invention is not limited thereto.

  The thickness of the organic light emitting medium layer 12 is 1000 nm or less, preferably 50 nm to 150 nm, even when formed by a single layer film or a multilayer film. In particular, the material of the hole transport layer of the polymer organic EL element has a large effect of covering the surface protrusions of the support base 10 and the anode 11, and it is more preferable to form a thick film of about 50 nm to 100 nm.

  As a method for forming the organic light emitting medium layer 12, a vacuum deposition method, a spin coating method, a spray coating method, a flexo method, a gravure method, a micro gravure method, an intaglio offset coating method, a printing method, an ink jet method, or the like is used depending on the material. be able to. When the organic light emitting medium layer 12 is made into a solution using a polymer, it is preferable to control the vapor pressure, solid content ratio, viscosity, etc. of the solvent according to the forming method. Solvents include water, xylene, anisole, cyclohexanone, mesitylene, tetralin, cyclohexylbenzene, methyl benzoate, ethyl benzoate, toluene, ethanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, methanol, isopropyl alcohol, ethyl acetate, butyl acetate, etc. These may be a single solvent or a mixed solvent. In order to improve coatability, it is more preferable to mix an appropriate amount of additives such as surfactants, antioxidants, viscosity modifiers and ultraviolet absorbers as necessary. As a method for drying the coating solution, it is sufficient to remove the solvent to such an extent that the characteristics of the organic EL element are not hindered, and the coating solution may be heated, decompressed, or heated and decompressed.

Next, the cathode 13 is formed on the organic light emitting medium layer 12. As the cathode 13 according to the present embodiment, a metal having a small work function (4 eV or less) (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof can be used. Examples of the material of the cathode 13 include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ). Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like can be mentioned. Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Particularly suitable are magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like. The cathode 13 can be formed by forming a thin film by a method such as a vacuum evaporation method or a sputtering method. Further, the sheet resistance as the cathode 13 is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 nm to 200 nm. In addition, since the emitted light is transmitted, if either one of the anode 11 or the cathode 13 of the organic EL element 20 is transparent or translucent, the emission luminance can be improved.

  Moreover, after forming the cathode 13 with a film thickness of 1 nm to 20 nm, the transparent transparent or translucent cathode 13 can be manufactured by forming the conductive transparent material of the anode 11 on the cathode 13. A top emission type organic EL element taken out from the cathode 13 side, or an organic EL element 20 in which both the anode 11 and the cathode 13 are transmissive can be manufactured.

  Next, the protective film 14 is formed on the entire surface of the organic EL element 20. The protective film 14 according to the present embodiment provides a long-life organic EL panel 100 by providing the protective film 14 having a gas barrier property so as to cover the organic EL element 20 in order to further improve the sealing performance. be able to. As the material of the protective film 14 according to the present embodiment, for example, an insulating material and a material that can be formed by a dry method are preferable. Metal oxides such as silicon oxide, aluminum oxide, chromium oxide, and magnesium oxide, and fluoride are used. Metal fluorides such as aluminum, magnesium fluoride and calcium fluoride, metal nitrides such as silicon nitride, aluminum nitride and chromium nitride, metal oxynitrides such as silicon oxynitride, DLC (diamond-like carbon), amorphous silicon film, etc. Inorganic materials can be used. The protective film 14 is particularly preferably a material having gas barrier properties. As a method for forming the protective film 14, a film forming method such as a resistance heating vapor deposition method, an electron beam vapor deposition method, a reactive vapor deposition method, an ion plating method, a sputtering method, or a CVD method can be used depending on the material. Although there is no restriction | limiting in particular as a film thickness of the protective film 14, About 10 nm-5000 nm are desirable, Furthermore, in order to protect the level | step difference of the anode 11, the organic light emitting medium layer 12, and the cathode 13, forming a thick film 100 nm or more is preferable. desirable.

  Furthermore, the protective film 14 may be a single layer or may have a multilayer structure using a plurality of separate materials. In the case where the protective film 14 has a multilayer structure, a plurality of inorganic oxides or inorganic nitrides may be stacked. Alternatively, for the purpose of further improving the flatness of the surface of the protective film 14, an inorganic oxide or inorganic nitride layer and an organic material layer may be stacked.

In the case of the top emission type, it is desirable to use a material having a transmittance of 75% or more in the visible region (400 nm to 700 nm) for the protective film 14. For example, inorganic oxides or nitrides such as SiO _x , SiN _x , SiN _x O _y , AlO _x , TiO _x , TaO _x , and ZnO _x can be used.

  Next, as shown in FIG. 1, a method for sealing the organic EL element 20 using the sealing substrate 50, the sheet-like adhesive 41, and the sheet-like adhesive 42 will be described.

[Sealing substrate 50]
The sealing substrate 50 is a flexible film, and examples of materials include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, and cellulose acetate. Cellulose esters such as butyrate, cellulose acetate propionate (CAP), cellulose acetate phthalate (TAC), cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, Norbornene resin, polymethylpentene, polyetherketone, polyimide, polyethersulfone (PES), polypheny Sulfide, polysulfones, polyether imide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic or polyarylate, trade name “Arton (registered trademark)” (manufactured by JSR) or trade name “ Use of cycloolefin resin such as “Apel (registered trademark)” (manufactured by Mitsui Chemicals), films made of metal foil such as aluminum and stainless steel and resin films laminated with metal films such as aluminum, copper, nickel and stainless steel it can. When the organic EL element 20 is used as a top emission type, the sealing substrate 50 is desirably made of a material having a transmittance of 75% or more in the visible region (400 nm to 700 nm). Although the film thickness of the sealing substrate 50 should just have about 10 nm-500 micrometers, it is more desirable that it is 30 nm-200 micrometers.

  By using a flexible film for the sealing substrate 50, the thickness and weight can be reduced. Further, unlike bonding with a rigid sealing substrate 50 such as glass, the organic EL panel 100 without bubbles can be manufactured because it can be bonded while being bent.

The flexible film used for the sealing substrate 50 has a water vapor transmission rate of 0.01 g / m ² · day or less and an oxygen transmission rate of 10 ⁻³ ml / m in order to extend the life of the organic EL element 20. A high barrier property of ² · day is required, and a barrier film (not shown) is formed on the surface of the flexible film as an inorganic film, an organic film, or a hybrid film of both. As a material for forming the barrier film, any material may be used as long as it has a function of suppressing intrusion of substances that cause deterioration of the organic EL element 20 such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like is used. it can. Further, in order to improve the brittleness of the barrier film, a composite film having a laminated structure of layers composed of these inorganic layers and organic materials is more preferable. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

  The method for forming the barrier film is not particularly limited, and for example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma polymerization Plasma CVD method, laser CVD method, thermal CVD method, coating method and the like can be used.

[Sheet adhesive 41 and sheet adhesive 42]
A sheet-like adhesive 42 is obtained by spreading an adhesive resin on the sealing substrate 50 and molding it into a sheet (film). Before the sheet-like adhesive 42 formed on the sealing substrate 50 is bonded to the support substrate 10 on which the organic EL element 20 is formed, the first protective film is put on the adhesive surface side of the sheet-like adhesive 42. Is suitable for storage stability and processability. The first protective film is desirably superior in peelability than the sealing substrate 50, and examples thereof include PET and polyester release films. By forming the sheet-like adhesive 52 on the sealing substrate 50, unlike the liquid adhesive, the shape stability is excellent, so there is no problem of dripping or liquid drift. Furthermore, it can also be stored in rolls or single sheets.

  Examples of the adhesive resin for forming the sheet-like adhesive 42 include photo radical polymerizable resins mainly composed of various acrylates such as polyester acrylate, polyether acrylate, epoxy acrylate, and polyurethane acrylate, and resins such as epoxy and vinyl ether. Examples thereof include a photo-cationic polymerizable resin as a main component, a photo-curing resin such as a thiol / ene-added resin, and a thermosetting adhesive resin made of an epoxy or acrylic resin. In addition, the sheet-like adhesive 42 is desirably low in moisture permeability, and does not generate a gas that causes deterioration during the production of the organic EL panel 100 or has a small amount generated, and may be deformed / Those with little change such as shrinkage and expansion are desirable. The film thickness of the sheet adhesive 42 is preferably 5 μm to 200 μm, and more preferably set so that the residual stress is as small as possible. Examples of the method for forming the sheet-like adhesive 42 on the sealing substrate 50 include a coating method such as a roll coating method, a spin coating method, a screen printing method, and a spray coating method, and a printing method, depending on the material.

  The sheet-shaped adhesive 41 is obtained by spreading an adhesive resin on the first protective film on the bonding surface side of the sheet-shaped adhesive 42 and molding it into a sheet shape (film shape). Similar to the sheet-like adhesive 42, it is preferable for storage stability and processability to cover the second protective film on the adhesive surface side of the sheet-like adhesive 41 until just before use. The second protective film is peeled off from the sheet-like adhesive 41 (first protective film / sheet-like adhesive 41 / second protective film), and the support substrate 10 on which the organic EL element 20 is formed (the protective film 14). Is transferred to an organic EL device 20) containing Thereafter, the first protective film is peeled off.

  The material of the sheet-like adhesive 41 can be the same as that of the sheet-like adhesive 42, but the sheet-like adhesive 41 is adhesive and close to the support substrate 10, and the sheet-like adhesive 42 is adhesive to the sealing substrate 50. It is preferable that the material is set to be a suitable material. As a material for the first protective film and the second protective film, for example, a release film such as PET or polyester is used, and the first protective film and the second protective film have different peelability. It is desirable to keep it.

  Similar to the sheet-like adhesive 41 and the sheet-like adhesive 42, it is desirable to have low moisture permeability, and it does not generate a gas that causes deterioration during the production of the organic EL element panel 100, or the generation amount is small, It is desirable that there is almost no change such as deformation, shrinkage, and expansion over time. The thickness of the sheet-like adhesive 41 is preferably 5 μm to 100 μm, and more preferably set so that the residual stress becomes as small as possible. Further, it is desirable that the sheet-like adhesive 41 and the sheet-like adhesive 42 have the same size as the sheet-like adhesive 41 and the sheet-like adhesive 42.

[Bonding method]
The sealing substrate 50 on which the sheet-like adhesive 42 is formed uses a sticking device, peels off the first protective film that has covered the sheet-like adhesive 42, and flexes the sheet so that bubbles do not enter. It is affixed on the support substrate 10 on which the adhesive 41 is laminated. Further, the adhesion may be improved by thermocompression bonding with an autoclave device or a diaphragm type vacuum laminator. Finally, curing is performed under the recommended curing conditions for the sheet adhesives 41 and 42.

  When the material of the support substrate 10 on which the organic EL element 20 is formed and the sealing substrate 50 are different in one type of adhesive, the interface between the support substrate 10 or the sealing substrate 50 and the adhesive is caused by the difference in thermal expansion coefficient. May cause peeling. However, the organic EL panel 100 according to the embodiment of the present invention can exhibit high adhesion by selecting a sheet-like adhesive suitable for the material of the support substrate 10 or the sealing substrate 50. In addition, the use of the sheet-like adhesive has good thin film and uniform film thickness, and since the liquid adhesive is not used, the sheet-like adhesive has an edge when the support substrate 10 and the sealing substrate 50 are bonded together. It does not protrude from the department. Since it is easy to control the thin film adhesive and the adhesive region, it is possible to manufacture the organic EL panel 100 having a long lifetime and a narrow frame.

  Examples 1 and 2 and a comparative example according to the embodiment of the present invention will be described below, but the present invention is not limited to the following examples.

  First, the organic EL element 20 shown in FIG. 2 was produced. Non-alkali glass was used as the support substrate 10. An ITO film having a thickness of 150 nm was formed as the anode 11 on the support substrate 10 by sputtering. After the anode 11 was formed, the ITO film was patterned by photolithography and wet etching.

Next, the support substrate 10 on which the ITO film was formed was cleaned, put into an oxygen plasma chamber, and washed with power of 100 W in an atmosphere of Ar / O ₂ = 1: 1 for 5 minutes.

  Next, the organic light emitting medium layer 12 includes a hole transport layer having a thickness of 50 nm made of a mixture of poly (3,4-ethylenedioxythiophene) and polystyrenesulfonic acid (PEDOT-PSS), poly [2- A light emitting layer having a thickness of 80 nm made of methoxy-5- (2′-ethylhexyloxy) -1,4-phenylenevinylene] (MEHPPV) was formed by a printing method. Hereinafter, the anode 11 and the organic light emitting medium layer 12 formed on the support substrate 10 are referred to as “substrate”.

  Next, the substrate was moved to a vapor deposition apparatus in which a metal vapor deposition chamber, a sputtering chamber, and a CVD chamber were connected. First, the substrate was moved to the vapor deposition chamber to form the cathode 13. The cathode 13 was formed by stacking Ca (calcium) with a thickness of 10 nm and Al (aluminum) with a thickness of 150 nm. Next, the substrate was moved to the CVD chamber, and a silicon nitride film as a protective film 14 was formed to a thickness of 1000 nm by the CVD method so as to cover the anode 11, the organic light emitting medium layer 12, and the cathode 13. Through the above steps, the organic EL element 20 shown in FIG. 2 was produced.

  Next, as shown in FIG. 1, the produced organic EL element 20 was sealed with a sheet-like adhesive 41. As the sheet-like adhesive 41, a single-wafer sheet made of release PET / epoxy thermosetting resin (20 μm) / polyster was used. An epoxy-based thermosetting resin was transferred to the single sheet so as to cover the protective film 14 using an automatic sticking apparatus.

  On the other hand, an acrylic thermosetting resin as a sheet-like adhesive 42 was spread on a sealing substrate 50 made of PET / aluminum foil (50 μm) to a film thickness of 20 μm by a coater method, and then covered with a polyester protective film. The sheet-like adhesive 52 is made into a single sheet, the first protective film is peeled off by an automatic sticking device, and the acrylic thermosetting resin is transferred to the glass substrate (supporting substrate 10) side formed up to the epoxy thermosetting resin. .

Next, the sheet-like adhesive 41 and the sheet-like adhesive 42 are bonded together, and heated and pressed for 15 minutes at 80 ° C. and 3 kg / cm ² with an autoclave device, and 6000 mJ / cm ² ultraviolet irradiation is performed, and bottom emission is performed. A mold type organic EL panel 100 was produced.

  In Example 2, the sealing substrate 50 is a polyethersulfone (PES) / acrylic UV curable resin / SiOx film barrier film, the sheet adhesive 42 is an epoxy UV curable resin, and the sheet adhesive 41 is an acrylic resin. A top emission type organic EL element panel 100 was manufactured by repeating the same procedure as in Example 1 except that UV curable resin and 20 nm thick Ca and 200 nm thick ITO were used for the cathode 13.

(Comparative Example 1)
A bottom emission type organic EL element panel was produced by repeating the same procedure as in Example 1 except that the epoxy ultraviolet curable resin as the sheet-like adhesive 41 was not provided on the support substrate 10 side.

  Table 1 shows the sheet-like adhesive 41, the sheet-like adhesive 42, the material of the sealing substrate 50, and the light of the organic EL element 20 of the organic EL panel 100 obtained in Example 1, Example 2, and Comparative Example 1. Indicates the direction to take out.

[Evaluation]
Each of the organic EL panels 100 obtained in Example 1, Example 2, and Comparative Example 1 was left in a constant temperature and humidity layer at 60 ° C. and 90% RH, and the light emitting surface was observed with an optical microscope. Table 2 shows the results of the dark spot (non-light emitting portion) area ratio at the initial stage and after leaving for 1500 hours.

  As can be seen from Table 2, the organic EL element panel 100 of Example 1 and Example 2 has a significantly lower dark spot area ratio and a longer life as compared with the organic EL element panel of Comparative Example 1, and the organic EL element It can be seen that 20 degradation does not occur.

It is a schematic sectional drawing which shows the organic electroluminescent panel which concerns on embodiment of this invention. It is a schematic sectional drawing which shows the organic EL element which concerns on embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Support substrate, 11 ... Anode, 12 ... Organic luminescent medium layer, 13 ... Cathode, 14 ... Protective film, 20 ... Organic EL element, 41 ... Sheet adhesive (support substrate side), 42 ... Sheet adhesive ( Sealing substrate side), 50 ... sealing substrate, 100 ... organic EL panel

Claims (9)

A support substrate;
An organic EL device comprising an anode, an organic light emitting medium layer and a cathode formed on the support substrate;
A first sheet-like adhesive formed on the organic EL element;
A sealing substrate for sealing the organic EL element;
And a second sheet-like adhesive formed separately from the first sheet-like adhesive and sandwiched between the first sheet-like adhesive and the sealing substrate. Organic EL element panel.   The organic EL element panel according to claim 1, wherein the organic EL element is further covered with a protective film having a visible transmittance of 75% or more. The support substrate is different in base material from the sealing substrate, has a water vapor permeability of 0.01 g / m ² · day or less and an oxygen permeability of 10 ⁻³ ml / m ² · day, and The organic EL element panel according to claim 1, wherein the organic EL element panel is colorless and transparent. The sealing substrate is a flexible film having a barrier property of a water vapor permeability of 0.01 g / m ² · day or less and an oxygen permeability of 10 ⁻³ ml / m ² · day, and a visible transmittance of 75. The organic EL element panel according to claim 1, wherein the organic EL element panel is at least%. In the organic EL element panel according to any one of claims 1 to 4,
An organic EL element panel characterized in that the light extraction direction is top emission or bottom emission. An organic EL element is formed by sequentially laminating an anode, an organic issuance medium layer, and a cathode on a support substrate,
Forming a first sheet-like adhesive on the support substrate side;
Forming a second sheet-like adhesive on the sealing substrate;
A method of manufacturing an organic EL element panel, wherein the first sheet-like adhesive and the second sheet-like adhesive are bonded and cured so as to face each other.   The method of manufacturing an organic EL element panel according to claim 6, wherein the organic EL element further has a protective film, and the visible transmittance of the protective film is 75% or more. The support substrate is different in base material from the sealing substrate, has a water vapor permeability of 0.01 g / m ² · day or less and an oxygen permeability of 10 ⁻³ ml / m ² · day, and The method for producing an organic EL element panel according to claim 6, wherein the organic EL element panel is colorless and transparent. The sealing substrate is a flexible film having a barrier property of a water vapor permeability of 0.01 g / m ² · day or less and an oxygen permeability of 10 ⁻³ ml / m ² · day, and a visible transmittance of 75. % Or more, The manufacturing method of the organic EL element panel in any one of Claims 6 thru | or 8 characterized by the above-mentioned.

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