JP6213254B2 - Method for manufacturing organic electroluminescence device - Google Patents

Description

  The present invention relates to a method for producing an organic electroluminescence element (hereinafter also referred to as “organic EL element”).

  The organic EL element is composed of an organic functional layer including a light emitting layer of an organic compound and an organic EL structure having a structure sandwiched between two electrodes, a first electrode (anode) and a second electrode (cathode), on an element substrate such as glass. Has been placed. The light emitting layer emits light by supplying a current between the anode and the cathode.

  The organic EL structure constituting the organic EL element is easily affected by moisture and oxygen, and if left in the air, the light emission performance is reduced by moisture and oxygen. For this reason, in the manufacturing process of an organic EL element, the process of forming the layer to seal on the organic EL structure for reducing the influence of the external field is performed.

  In recent years, with the expansion of the use of organic EL elements, etc., an organic EL structure is formed on a flexible element substrate such as a resin film, and a flexible sealing member such as a barrier film or a metal foil is provided. A manufacturing method of a solid-sealing type organic EL element that is sealed by adhesive bonding with an adhesive has been developed, and is being put to practical use as a manufacturing method of a thin and lightweight organic EL element having excellent moisture resistance.

  When the organic EL structure is formed by a vacuum process such as vapor deposition, it has been proposed from the viewpoint of productivity that the sealing process is performed under vacuum pressure continuously with the vacuum process. By performing the process continuously under vacuum pressure, it is possible to prevent light emission performance from deteriorating due to moisture and oxygen in the air, and to prevent particles from adhering to the surface of the organic EL structure, thereby improving the performance of the organic EL element. is there.

  In addition, as a manufacturing method for efficiently mass-producing organic EL elements at low cost, an organic functional layer and an electrode are formed on a long flexible substrate, and a long element substrate is formed by a roll-to-roll method. A method is considered that is performed while continuously or intermittently running.

  The roll-to-roll method can be used not only for forming an organic EL structure but also for forming a sealing member on a long flexible substrate as a separator film. The sealing member formed above and the organic EL structure can also be used for the above-described solid sealing method in which surface bonding is performed with an adhesive.

  Furthermore, the roll-to-roll manufacturing method has the advantage that production efficiency and yield can be improved because continuous production is possible.

  In order to prevent the adhesion of particles to the surface of the organic EL structure, the organic EL element is manufactured by the roll-to-roll method, after forming the organic EL structure on the element substrate under vacuum pressure, and continuously through an adhesive. It is preferable that the sealing member and the organic EL structure are bonded and solid-sealed. After solid sealing, it becomes a multilayer substrate in which an element substrate, an organic EL structure, an adhesive layer, a sealing member, and a separator film are laminated in this order. A long multilayer substrate produced by a roll-to-roll is wound up on a roll, stored, or transferred to another process.

  In Patent Document 1, an organic EL structure is formed on a long element substrate, and then a sealing member and an organic EL structure are continuously bonded via an adhesive layer to perform solid sealing. A method for manufacturing an EL element by a roll-to-roll method is described. Patent Document 1 describes that after forming a multilayer substrate by solid-sealing, the adhesive is cured, and the multilayer substrate on which the adhesive forming the adhesive layer is cured is taken up.

  When winding the multilayer substrate, an auxiliary member is applied to the end of the multilayer substrate, or the auxiliary member is superimposed on the multilayer substrate and wound to prevent contact between the element substrate and the surface of the separator film. In addition, a winding method of a multilayer substrate that suppresses damage to the film surface of the organic EL element is described.

JP 2006-294536 A

  However, in the manufacturing method described in Patent Document 1, since the long multilayer substrate is wound after the adhesive is cured under vacuum pressure, tightening due to vacuum pressure or roll-shaped multilayer substrate is not vacuumed. Tightening due to the pressure difference when the pressure is changed from atmospheric pressure to atmospheric pressure causes pressing of the cured adhesive layer, peeling of the sealing material composed of the sealing member and the adhesive layer, and generation of indentations on the surface of the organic EL element It was found that there was a problem that occurred. It has been found that when the peeling of the sealing material and the occurrence of indentation are remarkably generated, the performance of the organic EL element is deteriorated such as the deterioration of the sealing performance and the occurrence of light emitting defects, and the quality of the organic EL element is deteriorated.

  Further, in the method in which the auxiliary member is applied to the multilayer substrate in which the adhesive is cured under a vacuum pressure and wound, the sealing material is peeled off from the element substrate or the surface of the organic EL element due to the deformation of the multilayer substrate generated using the auxiliary member as a fulcrum. As a result, it was found that the indentation was remarkably generated, and the quality of the organic EL element was significantly lowered. In particular, if the sealing material is peeled off, sufficient sealing performance cannot be obtained, which causes deterioration in organic EL element performance such as a light emitting defect.

  Therefore, the object of the present invention is to prevent the peeling of the sealing material and the generation of indentation due to the tightening in the manufacturing method of the organic electroluminescence element using the roll-to-roll method, and the deterioration of the sealing performance and the occurrence of light emitting defects. It is providing the manufacturing method of the organic electroluminescent element which suppressed the fall of organic EL element performances, such as.

  Therefore, the present invention uses the following means in order to solve the above problems.

1. In the manufacturing method of an organic electroluminescence device using the roll-to-roll method, in vacuum Ji Yanba,
At least the sealing member and a sealing material formed in this order adhesive layer, at least an anode, an organic electroluminescent organic functional layer and the cathode are formed in the elongated element on a substrate elongated flexible substrate after pasting the luminescent structure, and Ri taken winding and a pasted the said sealing material said organic electroluminescent structure, then, outside of the vacuum chamber, a curing the adhesive layer A method for producing an organic electroluminescence device characterized in that:

  2. 2. The method of manufacturing an organic electroluminescence element according to 1 above, wherein the winding is performed with a tension of 100 N / m or less.

  According to the present invention, in the method for manufacturing an organic electroluminescence element using a roll-to-roll method, peeling of the sealing material due to tightening and generation of indentation are prevented, deterioration of sealing performance, generation of light emitting defects, etc. The manufacturing method of the organic electroluminescent element which suppressed the fall of organic EL element performance can be provided.

Schematic sectional view showing an example of the configuration of an organic EL element Outline sectional view showing the structure of the multilayer substrate Schematic showing an example of a manufacturing process of an organic electroluminescence element

The present invention provides a method of manufacturing an organic electroluminescence device using the roll-to-roll method, in vacuum Ji Yanba, the sealing member to the elongated separator film on, which is formed in the order of an adhesive layer sealant When, at least an anode, stuck an organic EL structure organic functional layer and the cathode are formed as a multilayer board with the elongated element substrate, Ri taken up the multi-layer substrate prepared, then, the vacuum chamber Outside, by curing the adhesive layer, it is possible to suppress the peeling of the sealing material and the generation of indentation due to the tightening, the deterioration of the organic EL element performance such as the deterioration of the sealing performance and the occurrence of light emitting defects, the organic EL It can suppress that element quality falls.

  It was found that in a form in which a brittle organic EL structure is solid-sealed with a very thin film, it is very important to wind up the adhesive layer before it is cured. In the manufacturing method of the solid sealing type organic EL element, the organic EL structure and the sealing material are closely adhered. In such a form of solid sealing, when the adhesive is cured and wound in a roll shape, the organic EL structure is pressed by the cured adhesive layer by tightening. When a fragile organic EL structure is pressed with a very thin film, the organic EL element performance is deteriorated. Furthermore, when the pressure of the adhesive cured by tightening is increased, it affects not only the organic EL structure but also the element substrate and the sealing material. Peeling occurs. In particular, it was found that the tendency appears remarkably under vacuum pressure.

≪Organic EL element≫
Below, the structure of the organic EL element of this embodiment is demonstrated in detail using FIG. The invention is not limited to the following embodiments within a range including the characteristics, and includes various modifications.

  FIG. 1 is a schematic cross-sectional view showing an example of the configuration of an organic EL element. In the organic EL element 1 of the present embodiment, the organic EL structure 2 is sealed by a sealing material 3 in order to keep the organic EL structure 2 in the organic EL element in a low humidity environment and to shield and protect it from the external environment. It is sandwiched and sealed and sealed.

  Here, the sealing material 3 has a sealing member 15 having an adhesive layer 14 formed on the surface, and the adhesive layer 14 adheres to and adheres to the organic EL structure, whereby the organic EL structure. Is sealed.

  The organic EL structure 2 is formed on at least the first electrode 11 formed on the element substrate 16, the organic functional layer 12 formed on the first electrode 11 and including the light emitting layer, and the organic functional layer 12. The second electrode 13 is provided and is in the form of a thin film. When a voltage is applied between both electrodes of the organic EL element 1, the light emitting layer emits light.

  The organic EL element 1 according to the present invention includes an element substrate 16 having an organic EL structure 2 formed on the surface and a sealing member 15 having an adhesive layer 14 formed on the surface. It has a multilayer structure formed by bonding on the surface where the EL structure 2 is formed and the surface where the adhesive layer 14 of the sealing member 15 is formed.

[Element substrate]
Here, the element substrate according to the present invention will be described.

  The element substrate is a substrate serving as a base when forming an organic EL element. The element substrate is preferably flexible and has mechanical strength, heat resistance when an organic EL element is produced on the element substrate, gas barrier properties against water vapor and oxygen, and the like. The element substrate is preferably made of a transparent resin in order to transmit the emitted light.

  Examples of the material constituting the element substrate include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane (registered trademark), cellulose diacetate, cellulose triacetate (TAC), and cellulose acetate butyrate. Rate, cellulose acetate propionate (CAP), cellulose acetates such as cellulose acetate phthalate, cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, poly Methyl pentene, polyether ketone, polyimide, polyether sulfone (PES), polyphenylene sulfi , Polysulfone, polyetherimide, polyetherketoneimide, polyamide, fluororesin, polymethylmethacrylate, polyacrylic ester, polyarylate, arton (registered trademark, manufactured by JSR) or appel (registered trademark, manufactured by Mitsui Chemicals) And cycloolefin-based resins. In addition, when the emitted light is transmitted from the sealing member, a material other than the transparent resin can be selected. For example, a metal such as copper, copper alloy, aluminum, aluminum alloy, gold, nickel, titanium, stainless steel, and tin. Is mentioned. One of these may be used alone, or two or more of these may be mixed or multilayered.

  Although the thickness of the element substrate is not particularly limited, it is preferably 50 to 500 μm in view of molding processability, handleability, and the like. The thickness of the element substrate can be measured using a micrometer.

  The organic EL element is formed on the surface of the element substrate. The organic EL element only needs to be formed on the surface of at least one side of the element substrate. And an organic EL element can be sealed and sealed by bonding in the surface in which the organic EL element of the element substrate was formed, and the surface in which the adhesive bond layer of the sealing material was formed. In addition, the organic EL element may be formed on both sides of the element substrate, and two sealing materials may be bonded from both sides of the element substrate to seal and seal the organic EL elements on both sides. it can.

(Gas barrier layer)
It is preferable that one or two or more gas barrier layers are formed between the element substrate and the light emitting layer from the viewpoint of moisture resistance.

  The material for forming the gas barrier layer is not particularly limited, and examples thereof include an inorganic film, an organic film, or a hybrid film of both. A material having a function of suppressing entry of an element that causes deterioration of the element such as moisture or oxygen is preferable. For example, a metal oxide such as silicon oxide or silicon dioxide, a metal nitride such as silicon nitride, or the like can be used. Furthermore, in order to further improve the strength of the gas barrier layer, it is preferable to have a layered structure of an inorganic layer and an organic functional layer. The stacking order of the inorganic layer and the organic functional layer is not particularly limited, but it is preferable to stack both layers alternately several times.

[Organic EL structure]
The organic EL structure has a configuration in which an organic functional layer of an organic compound is sandwiched between two electrodes, a first electrode (anode) and a second electrode (cathode). The organic functional layer includes at least one light emitting layer.

(First electrode)
The first electrode (anode) is an electrode film that supplies (injects) holes to the organic functional layer (specifically, the light emitting layer). The material type and physical properties of the first electrode are not particularly limited and can be set arbitrarily. For example, the first electrode can be formed of a material having a high work function (4 eV or more), for example, an electrode material such as a metal, an alloy, an electrically conductive compound, and a mixture thereof. The first electrode may be made of a light-transmitting material (transparent electrode) such as indium tin oxide (ITO) or indium zinc oxide.

  The sheet resistance as the first electrode (anode) is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 to 1000 nm, preferably 10 to 200 nm.

(Organic functional layer)
Each layer constituting the organic functional layer will be described below. However, since a specific material or the like of each layer of the organic functional layer can be a known material, the description thereof is omitted. In addition, since a known method such as a vapor deposition method or a coating method can be applied to the method for forming the organic functional layer, the description thereof is omitted.

Preferred examples of the lamination of the organic functional layer are as follows. In the following (1) to (6), the layer described above is usually provided on the first electrode (anode) side, and is then laminated on the second electrode (cathode) side in the order described below. The
(1) Light emitting layer / electron transport layer (2) Hole transport layer / light emitting layer / electron transport layer (3) Hole transport layer / light emitting layer / electron injection layer (4) Hole transport layer / light emitting layer / hole Blocking layer / electron transport layer (5) hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer (cathode buffer layer)
(6) Hole injection layer (anode buffer layer) / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer (7) Hole injection layer / hole transport layer / light emitting layer / electron Transport layer / electron injection layer (light emitting layer)
The light emitting layer is directly injected from the first electrode or from the first electrode through the hole transport layer and the like, and directly from the second electrode (cathode) or from the second electrode through the electron transport layer or the like. This is a layer that emits light by recombination with the injected electrons. Note that the portion that emits light may be inside the light emitting layer, or may be an interface between the light emitting layer and a layer adjacent thereto.

  The light emitting layer is preferably formed of an organic light emitting material including a host compound (host material) and a light emitting material (light emitting dopant compound). When the light emitting layer is configured in this way, an arbitrary emission color can be obtained by appropriately adjusting the emission wavelength of the light emitting material, the type of the light emitting material to be contained, and the like. In addition, by configuring the light emitting layer in this way, light can be emitted from the light emitting material in the light emitting layer.

  The total thickness of the light emitting layers can be set as appropriate according to desired light emission characteristics and the like. For example, the total thickness of the light emitting layer is 1 nm or more and 200 nm or less from the viewpoints of uniformity of the light emitting layer, prevention of unnecessary application of a high voltage during light emission, and improvement of stability of light emission color with respect to driving current. It is preferable to do. In particular, from the viewpoint of a low driving voltage, the total thickness of the light emitting layers is preferably 30 nm or less.

  The host compound contained in the light emitting layer is preferably a compound having a phosphorescence quantum yield of phosphorescence emission at room temperature (25 ° C.) of 0.1 or less, and more preferably 0.01 or less.

  The volume ratio of the host compound in the light emitting layer is preferably 50% or more of various compounds contained in the light emitting layer.

  As the light-emitting material contained in the light-emitting layer, for example, a phosphorescent light-emitting material (phosphorescent compound or phosphorescent compound), a fluorescent light-emitting material, or the like can be used. Note that one light emitting layer may contain one kind of light emitting material, or may contain a plurality of kinds of light emitting materials having different light emission maximum wavelengths. By using a plurality of types of light emitting materials, a plurality of lights having different emission wavelengths can be mixed to emit light, whereby light of any emission color can be obtained. Specifically, for example, white light can be obtained by including a blue light emitting material, a green light emitting material, and a red light emitting material (three kinds of light emitting materials) in the light emitting layer.

(Injection layer (hole injection layer, electron injection layer))
The injection layer is a layer for reducing the drive voltage and improving the light emission luminance. The injection layer is usually provided between the electrode and the light emitting layer. The injection layer is generally roughly divided into two. That is, the injection layer is roughly classified into a hole injection layer that injects holes (carriers) and an electron injection layer that injects electrons (carriers). The hole injection layer (anode buffer layer) is provided between the first electrode and the light emitting layer or the hole transport layer. The electron injection layer (cathode buffer layer) is provided between the second electrode and the light emitting layer or the electron transport layer.

(Blocking layer (hole blocking layer, electron blocking layer))
The blocking layer is a layer for blocking the transport of carriers (holes, electrons). The blocking layer is generally roughly divided into two. That is, the blocking layer is broadly classified into a hole blocking layer that blocks hole (carrier) transport and an electron blocking layer that blocks electron (carrier) transport.

  The hole blocking layer is a layer having the function of an electron transport layer (electron transport function) described later in a broad sense. The hole blocking layer is formed of a material having an electron transport function and a small hole transport capability. By providing such a hole blocking layer, the injection balance between holes and electrons in the light emitting layer can be made suitable. Thereby, the recombination probability of electrons and holes can be improved.

  In addition, as a hole-blocking layer, the structure of the electron carrying layer mentioned later is applicable similarly as needed. Further, when a hole blocking layer is provided, the hole blocking layer is preferably provided adjacent to the light emitting layer.

  On the other hand, the electron blocking layer is a layer having a function of a hole transport layer (hole transport function) described later in a broad sense. The electron blocking layer is formed of a material having a hole transport function and a small electron transport capability. By providing such an electron blocking layer, the injection balance between holes and electrons in the light emitting layer can be made favorable. Thereby, the recombination probability of electrons and holes can be improved. In addition, as an electron blocking layer, the structure of the positive hole transport layer mentioned later is similarly applicable as needed.

  The thickness of the blocking layer is not particularly limited, but is preferably 3 nm or more, more preferably 5 nm or more, and preferably 100 nm or less, more preferably 30 nm or less.

(Transport layer (hole transport layer, electron transport layer))
The transport layer is a layer that transports carriers (holes and electrons). The transport layer is generally roughly divided into two. That is, the transport layer is roughly classified into a hole transport layer that transports holes (carriers) and an electron transport layer that transports electrons (carriers).

  The hole transport layer is a layer that transports (injects) holes supplied from the first electrode to the light emitting layer. The hole transport layer is provided between the first electrode or the hole injection layer and the light emitting layer. The hole transport layer also acts as a barrier that prevents the inflow of electrons from the second electrode side. Therefore, the term hole transport layer may be used in a broad sense to include a hole injection layer and / or an electron blocking layer. Note that only one hole transport layer may be provided or a plurality of layers may be provided.

  The electron transport layer is a layer that transports (injects) electrons supplied from the second electrode to the light emitting layer. The electron transport layer is provided between the second electrode or electron injection layer and the light emitting layer. The electron transport layer also acts as a barrier that prevents the inflow of holes from the first electrode side. Therefore, the term electron transport layer may be used in a broad sense to include an electron injection layer and / or a hole blocking layer. Note that only one electron transport layer or a plurality of electron transport layers may be provided.

  Electron transport material (hole blocking) used in the electron transport layer (when the electron transport layer has a single layer structure, the electron transport layer, and when multiple electron transport layers are provided, the electron transport layer located closest to the light emitting layer) There are no particular restrictions on the material that may also serve as a material. However, as the electronic material used for the electron transport layer, a material having a function of transmitting (transporting) electrons injected from the second electrode to the light emitting layer is usually applicable.

(Second electrode)
The second electrode (cathode) is an electrode film that supplies (injects) electrons to the light emitting layer. The material constituting the second electrode is not particularly limited, but is usually an electrode such as a material having a small work function (4 eV or less), for example, a metal (electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof. Formed of material.

  In the organic EL element, when light is extracted from the second electrode side, the second electrode can be formed of a light-transmitting electrode material, like the first electrode. In this case, for example, after forming a metal film made of an electrode material for forming a cathode so as to have a film thickness of 1 nm or more and 20 nm or less, a film made of a conductive transparent material described in the first electrode is formed on this metal film. Thus, a transparent or translucent second electrode can be formed.

[Encapsulant]
In the present invention, the sealing material includes at least a sealing member and an adhesive layer, and an adhesive is formed on the flexible sealing member. By sticking the sealing material to the organic EL structure, it can be blocked or protected from the external environment. The sealing material is formed on a long flexible substrate in the order of at least a sealing member and an adhesive layer. As the flexible substrate, the same substrate as the element substrate described above can be used.

  The sealing material can be processed into a shape corresponding to the organic EL structure. The shape is not particularly limited as long as a desired sealing performance can be obtained. Improvement in productivity can be expected by processing the shape of the sealing material and pasting it onto the organic EL structure.

(Sealing member)
Next, the sealing member according to the present invention will be described.

  The sealing member is for blocking and protecting the organic EL element and the like from the external environment. The sealing member is preferably flexible and has mechanical strength, gas barrier properties against water vapor and oxygen, and the like.

  Examples of the material constituting the sealing member include thermoplastics such as ethylene tetrafluoroethylene copolymer, polyethylene, polypropylene, polystyrene, polymethyl methacrylate, nylon, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, and polyethersulfone. Resin, urea resin, melamine resin, phenol resin, resorcinol resin, epoxy resin, unsaturated polyester resin, polyurethane resin, curable resin such as acrylic resin, copper, copper alloy, aluminum, aluminum alloy, gold, nickel, titanium, stainless steel And metals such as tin.

  These materials may be used alone or as a multi-layer sheet in which a plurality of types of materials are mixed or pasted, extruded, co-extruded, etc., if necessary. is there. Furthermore, in order to obtain desired physical properties, it is possible to produce various combinations of the thickness, density, molecular weight, and the like of the sheet to be used.

  The thickness of the sealing member is not particularly limited, but is preferably 10 μm or more and 300 μm or less in consideration of molding processability, handleability, stress cracking resistance of the gas barrier layer, and the like. In addition, the thickness of the sealing member here can be measured using a micrometer.

When using the above thermoplastic resin or curable resin as the sealing member, it is preferable to form a gas barrier layer on the sealing member by a vapor deposition method or a coating method. Examples of the gas barrier layer include a metal vapor deposition film, an inorganic vapor deposition film, and a metal foil. As metal vapor deposition film and inorganic vapor deposition film, thin film handbook p879-p901 (Japan Society for the Promotion of Science), vacuum technology handbook p502-p509, p612, p810 (Nikkan Kogyo Shimbun), vacuum handbook revised edition p132-p134 (ULVAC Japan) Examples thereof include vapor-deposited films as described in Vacuum Technology KK). For example, metals such as In, Sn, Pb, Au, Cu, Ag, Al, Ti, Ni, W, MgO, SiO, SiO ₂ , Al ₂ O ₃ , GeO, NiO, CaO, BaO, Fe ₂ O ₃ , Y ₂ O ₃ , TiO ₂ , Cr ₂ O ₃ , Si _x O _y (x = 1, y = 1.5 to 2.0), Ta ₂ O ₃ , ZrN, SiC, TiC, PSG, Si ₃ N ₄ , SiN, single crystal Si, amorphous Si, and the like. Examples of the metal foil material include metal materials such as aluminum, copper, and nickel, and alloy materials such as stainless steel and aluminum alloy. Aluminum is preferable in terms of workability and cost. One of these may be used alone, or two or more may be used in any combination and ratio.

  The film thickness of the metal vapor-deposited film and the inorganic vapor-deposited film is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 300 nm or less, from the viewpoint of easy formation of the vapor-deposited film. The film thickness of the metal foil is 1 to 100 μm, preferably 10 μm to 50 μm, from the viewpoint of handling at the time of manufacture and thinning of the panel. In order to facilitate handling during production, a resin film such as polyethylene terephthalate or nylon may be laminated in advance. Furthermore, a protective layer made of a thermoplastic resin may be provided on the gas barrier layer.

(Adhesive layer)
The adhesive layer is formed on the surface of the sealing member, and may be formed on the surface of at least one side of the sealing member. And an organic EL element can be sealed and sealed by bonding in the surface in which the adhesive bond layer of the sealing member was formed, and the surface in which the organic EL element of the element substrate was formed. In addition, a long adhesive layer is formed on both sides of the sealing member, and two element substrates are bonded from both sides of the sealing member to seal the organic EL elements on both sides. It can also be sealed.

  As the adhesive constituting the adhesive layer, any of thermosetting resins, photocurable resins, and thermoplastic resins can be used. It is preferable to use a resin that is excellent in moisture resistance and water resistance, has less volatile components, and has less shrinkage during curing.

  As the thermosetting resin, for example, epoxy resin, acrylic resin, silicone resin, urea resin, melamine resin, phenol resin, resorcinol resin, unsaturated polyester resin, polyurethane resin, etc. Resin.

  Examples of the photocurable resin include radical curable resins such as ester acrylates, urethane acrylates, epoxy acrylates, melamine acrylates, acrylic resin acrylates, etc., or radical photocurable resins using resins such as urethane polyesters, epoxies, vinyl ethers, and the like. Examples thereof include a cationic photocurable resin using a resin.

  Examples of the thermoplastic resin include polyethylene, polypropylene, polyamide, polyethylene terephthalate (PET), polyvinyl alcohol (PVA), ethylene-vinyl acetate copolymer (EVA), ethylene-propylene copolymer, ethylene-acrylic acid copolymer. Polymers, ethylene-methacrylic acid copolymers, vinylidene chloride (PVDC), ionomers and the like can be used. Among them, acid modified products of polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer, which have excellent adhesion to the substrate, acid modified products of ethylene / vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene- A methacrylic acid copolymer is preferred. In particular, acid-modified products of polyethylene and polypropylene that have few outgas components that degrade the organic EL element are preferable.

  The outgas refers to the energy applied to cure the adhesive forming the adhesive layer, and the solvent, water, or reaction product gas mixed in the material forming the sealing material is vaporized or becomes a vacuum pressure. This is a gas released by moisture desorption from peripheral devices such as a chamber wall surface and a roll when the temperature of the space (inside the chamber) rises. Moisture and acid contained in the outgas cause a light emission defect due to a reaction between the organic EL structure and water, and causes an increase in driving voltage due to oxidation of the electrode surface, causing deterioration of the organic EL element performance.

  Outgas is measured by using a Pirani vacuum gauge or ionization vacuum gauge before and after the step of curing the adhesive, and comparing the vacuum levels before and after the step of curing the adhesive. Can be confirmed. In addition, a gas analyzer (quadrupole mass spectrometer: Qmass) can ionize outgas components and identify components contained in the outgas.

  The thickness of the adhesive layer is preferably 1 μm to 100 μm from the viewpoint of sealing performance and panel thinning. As a method of forming an adhesive layer on the sealing member, gravure coating, roll coating, bar coating, die coating, knife coating, hot melt coating, dipping, spin depending on the type of adhesive constituting the adhesive layer. Coating methods such as coating and spray coating, and printing methods such as screen printing can be used. Moreover, in order to remove moisture contained in the adhesive layer, a desiccant such as barium oxide or calcium oxide may be mixed.

  It is preferable to add a filler to the adhesive constituting the adhesive layer as necessary. The addition amount of the filler is preferably 5 to 70% by volume in consideration of adhesive strength. Moreover, the magnitude | size of the filler to add considers adhesive force, the thickness of the adhesive bond layer after bonding, etc., and 1 micrometer-100 micrometers are preferable. The kind of filler to be added is not particularly limited, and examples thereof include soda glass, non-alkali glass, or silica, titanium dioxide, antimony oxide, titania, alumina, zirconia, tungsten oxide, and other metal oxides.

≪Method for manufacturing organic EL element≫
The organic EL device manufacturing method of the present invention includes a sealing material formed in the order of a sealing member and an adhesive layer on a long flexible substrate (separator film) in a vacuum chamber, at least an anode to scale an element substrate, the organic functional layer and bonded combined multilayer substrate formed by an organic EL structure cathode is formed, Ri preparative wound, then, outside of the vacuum chamber, the adhesive It is characterized by curing the agent layer .

  Therefore, the manufacturing process of the organic EL device of the present invention includes at least a step of feeding a long separator film on which a sealing material is formed, a step of feeding a long device substrate from a roll, and an organic EL on the device substrate. The step of forming the structure, the organic EL structure formed on the element substrate, and the sealing material formed on the separator film are bonded to the surface on which the adhesive layer of the sealing material is formed. A step of forming the substrate and a step of winding the multilayer substrate into a roll before the adhesive layer is cured.

  A schematic structure of the multilayer substrate according to the present invention is shown in FIG. The multilayer substrate 29 has a structure in which the organic EL structure 2 and the sealing material 3 are laminated between the long and flexible element substrate 16 and the separator film 17 and arranged at a uniform interval.

  In the present invention, the separator film is not particularly limited as long as it has flexibility, but it is preferably a flexible film from the viewpoint of supporting or protecting the organic EL structure or the sealing material. A porous film or a film having a high gas permeability can be used, but a resin film is preferable from the viewpoint of the strength of the film and the protection of the sealing material surface. The separator film can be made of the same material as the sealing member or the element substrate. By using the same material as the sealing member or the element substrate, the manufacturing cost can be suppressed.

  The material used for the separator film may be used alone or as a multi-layered long sheet that is mixed by mixing, pasting, extrusion laminating, coextrusion, etc. Is possible. Furthermore, in order to obtain desired physical properties, it is possible to produce various combinations of the thickness, density, molecular weight, and the like of the long sheet to be used, and it may have a multilayer structure.

  By using a long and flexible film as a separator film, it is possible to produce roll-to-roll sealing films and organic EL devices that produce flexible films while running continuously. It becomes.

  Moreover, you may provide an adhesion layer on a separator film. The pressure-sensitive adhesive layer formed on the separator film is not particularly limited, but it is preferable to use an acrylic resin from the viewpoint of production cost and handling ease. The same material as the adhesive layer can also be used.

  Below, the manufacturing process of the organic EL element in the case where the thermosetting adhesive of the present invention is used for the adhesive layer will be described in more detail with reference to FIG. The present invention is not limited to the following embodiments as long as the characteristics are included, and includes various modifications.

[Feeding process]
The unwinding step is a step of unwinding the element substrate from a roll wound with a long element substrate, or a step of unwinding the separator film from a roll wound with a long separator film on which a sealing material is formed.

  FIG. 3 is a schematic view showing an example of manufacturing an organic EL element by a roll-to-roll method. A first feeding unit 20 including a roll 21 around which a long element substrate is wound and a guide roller 22 for guiding the element substrate 16 fed out from the roll 21 is installed. The element substrate 16 is drawn out from the roll 21 via the guide roller 22.

  Furthermore, the 2nd delivery part 23 provided with the guide roller 25 for guiding the separator film 17 drawn | fed out from the roll 24 with which the long separator film 17 with which the sealing material was formed in the single side | surface is wound, and roll 24 is installed. Has been. Separator film 17 is fed from roll 24 through guide roller 25. At this time, the adhesive layer is formed on the surface of the sealing member on the side not in contact with the separator film 17 of the sealing material 3.

[Formation process of organic EL structure]
The organic EL structure forming unit 26 in FIG. 3 is a step of cleaning and drying the element substrate 16 drawn out from the first drawing-out unit and forming each constituent layer of the organic EL structure. In the step of forming the organic EL structure according to the present invention, the vacuum pressure is not particularly limited, but it is desirable to form the organic EL structure at a vacuum pressure of 10 ⁻⁴ Pa or less.

(Element substrate preparation process)
In the substrate preparation step, for example, the element substrate 16 wound in a roll shape is drawn out to the cleaning unit, immersed in an ultrasonic cleaning tank and subjected to ultrasonic cleaning, and then rinsed with pure water in the rinse tank, Rinse with a shower head and dry in the drying section.

  After that, the transfer speed with the subsequent process is adjusted by the buffer unit, and is transferred to the plasma tank through the preliminary chamber a and the preliminary chamber b (both not shown). Gate valves for allowing the element substrate 16 to pass are provided at the entrances of the respective spare chambers, between the spare chambers, and between the spare chambers and the plasma tank. The gate valve has an orifice (a valve is formed so that the gap can be adjusted) so that the surface of the element substrate 16, particularly the surface on the organic EL structure 2 formation side, can pass through without contact. As a result, the element substrate 16 is carried into the plasma chamber with the degree of decompression adjusted by the differential decompression by the decompression preliminary chamber and the further decompression preliminary chamber.

  Each decompression preparatory chamber and the plasma chamber are differentially evacuated by a vacuum pump (not shown) respectively provided, and from the atmospheric pressure environment to the plasma chamber, the vacuum environment required for the plasma chamber is reached. It is adjusted as follows.

In the plasma tank, the element substrate 16 is cleaned with oxygen plasma under a vacuum pressure of 10 ⁻⁴ Pa, for example.

  After the cleaning, the element substrate 16 is then transferred to the first electrode forming process.

(First electrode forming step)
In the first electrode formation step, for example, the first electrode 11 (anode) having the extraction electrode portion is formed by a sputtering method using a pattern mask. In this method, for example, when a film of ITO is formed on the element substrate 16 by a sputtering method as a material of the first electrode 11 (anode), the film is formed using a mask having a necessary shape in advance.

(Hole transport layer forming process)
Next, in the hole transport layer forming step, for example, a hole transport layer that is an organic compound is laminated on the entire surface of the first electrode 11 (anode) except for a portion that becomes an electrode by a vacuum deposition method using a pattern mask. The

  Then, as described later, the light emitting layer, the electron injection layer, and the second electrode 13 (cathode) are formed on the hole transport layer formed as described above, and the organic EL structure 2 is manufactured.

(Light emitting layer forming step)
In the light emitting layer forming step, the light emitting layer is formed by vacuum deposition on the hole transport layer excluding the extraction electrode portion of the element substrate 16 on which the hole transport layer is formed.

(Electron injection layer forming process)
In the electron injection layer forming step, the electron injection layer is formed by, for example, a vacuum evaporation method on the light emitting layer already formed on the element substrate 16 continuously supplied from the feeding portion. The thickness of the electron injection layer is preferably in the range of 0.1 nm to 5 μm.

(Second electrode forming step)
In the second electrode formation step, for example, the second electrode 13 (cathode) having an extraction electrode on the element substrate 16 continuously supplied from the electron injection layer formation step is masked on the already formed electron injection layer. A pattern is formed. The sheet resistance as the second electrode 13 (cathode) is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. At this stage, the organic EL structure 2 having the configuration of the first electrode (anode) / hole transport layer / light emitting layer / electron injection layer / second electrode (cathode) is fabricated on the element substrate 16.

  In the above description of the second electrode (cathode) forming step and the electron injecting layer (cathode buffer layer) forming step, the case of the vapor deposition apparatus is shown. However, the second electrode 13 (cathode) and the electron injecting layer (cathode buffer layer) are formed. The method is not particularly limited. For example, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma polymerization method, plasma CVD method, laser A CVD method, a thermal CVD method, a coating method, or the like can be used.

  The element substrate 16 having the organic EL structure 2 formed up to the second electrode is transported to the next step.

[Bonding process]
In the bonding step, the adhesive layer is softened using a curing means under vacuum pressure, and the organic EL structure formed on the element substrate and the sealing material formed on the separator film are bonded to each other. In this step, the surface on which the agent layer is formed is bonded to form a multilayer substrate.

  The softening of the adhesive layer means that the viscosity of the adhesive constituting the adhesive layer is set to 10 Pa · s or more and less than 5000 Pa · s using the softening means. When the organic EL structure and the adhesive layer are bonded, the viscosity of the adhesive constituting the adhesive layer is preferably 50 to 200 Pa · s.

  When the adhesive constituting the adhesive layer is a thermosetting resin or a photocurable resin, it is necessary to soften the adhesive before bonding so that the adhesive has tackiness. is there. By softening the adhesive, the element substrate and the sealing member are adhered to each other, and the organic EL structure is hermetically sealed between both substrates.

  When the adhesive constituting the adhesive layer is a thermosetting resin, it is preferable that the softening means of the adhesive in the softening step is heated at a temperature lower than the curing start temperature of the adhesive. When the adhesive constituting the adhesive layer is a photocurable resin, it is preferably a semi-solid having tackiness that has not been crosslinked or cured by light irradiation. A softening means is not required when the adhesive has tackiness that can be pre-adhered at the time of bonding.

  In the bonding step of the organic EL structure and the sealing material according to the present invention, the vacuum pressure is not particularly limited, but the organic EL structure is at a vacuum pressure of 10 Pa or less which is a range in which the sealing material is not damaged or deformed. It is desirable to paste the body and the sealing material. By bonding under vacuum pressure, air or the like is not involved, and the thickness of the sealing material becomes uniform by bonding the organic EL structure and the sealing material within the above-described vacuum pressure range. Therefore, it can bond with adhesiveness. Therefore, uniform sealing performance can be obtained on the bonding surface, and improvement in organic EL element performance can be expected.

  The method of bonding is a thermocompression bonding method using a bonding roll, but the means for bonding is not particularly limited. Various means such as roll lamination, flat plate bonding, and diaphragm bonding can be used. In this embodiment, the bonding roll is used as a typical bonding means.

  In FIG. 3, the element substrate 16 on which the organic EL structure on the substrate is formed in the organic EL structure forming unit 26 and the sealing material 3 on the separator film 17 fed out from the roll 24 are respectively discharged from the feeding unit. Since it is bonded, it is conveyed to the bonding unit 27. The bonding unit 27 includes a bonding roller 28 that bonds the element substrate 16 and the sealing material 3 under vacuum pressure.

  The adhesive layer formed on one surface of the sealing material 3 is bonded by the bonding roller 28 while being softened by the heating of the bonding roller 28. By heating the laminating roller 28, the time during which heat is applied to the multilayer substrate can be limited to the time passing between the laminating rollers 28, and the temperature of the laminating roll 12 is higher than the curing start temperature of the adhesive. Also, it is possible to control the generation of outgas by making the temperature low.

  If the adhesive constituting the adhesive layer has a viscosity of 10 Pa · s or more and less than 5000 Pa · s immediately before the bonding roller 28, special treatment is optional. However, when the adhesive which comprises an adhesive bond layer is a thermosetting resin, attention is paid so that heating temperature may not exceed hardening start temperature.

  The viscosity of the adhesive composing the adhesive layer can be measured with a normal polymer viscometer. For example, it can be measured using a rheometer DAR-100 manufactured by REOLOGICA. Using the same resin sample as the adhesive that makes up the adhesive layer that is the object to be measured, by measuring the viscosity when placed in the same atmosphere (temperature, etc.) temperature as at the time of bonding, Can be certified.

  Moreover, the curing start temperature of the thermosetting resin is the rise of the exothermic peak due to curing when the thermosetting resin is heated at a heating rate of 5 ° C./min in a nitrogen atmosphere using DSC. Defined with temperature.

  The laminating roller 28 is a so-called nip roller composed of a pair of upper and lower rollers. The element substrate 16 and the sealing material 3 are bonded to each other, and a multilayer substrate 29 in which the organic EL element is sealed and sealed with the softened adhesive layer is formed. The number of rollers may be two in a pair, or may be further increased to four in two pairs as necessary. Further, the nip pressure and the rotation speed of the roller are appropriately set to such a condition that the element substrate 16 and the sealing material 3 can be bonded and the organic EL element is not damaged.

In order to prevent the outgas generated in the curing process from affecting the organic EL element before pasting (before solid sealing) and degrading the performance of the organic EL element, a vacuum chamber in which the adhesive curing process is performed. were separated, intends row in different chambers.

In addition, from the viewpoint of maintaining productivity or the environment in the vacuum chamber in which the bonding process is performed and the degree of vacuum, the multilayer substrate manufactured in the bonding process is wound up before the adhesive layer is cured. It intends rows curing the adhesive at a different location from the chamber was carried out the winding of the substrate.

[Winding process]
The winding process is a process in which the multilayer substrate is wound into a roll before the adhesive layer is cured at a vacuum pressure of 10 Pa or less.

  In FIG. 3, the winding unit 30 includes a guide roller 31 and a winding roll 32. The multilayer substrate 29 before the adhesive layer is cured at the winding unit 30 is wound around the winding roll 32 with a winding tension of 100 N / m or less.

  The winding tension is the tension applied to the winding roll 32 when starting to wind the roll. The winding tension is preferably 100 N / m or less, more preferably 10 to 50 N / m, from the viewpoint of winding. The winding tension can be measured using a tension detector (AD-4820-53 manufactured by A & D). Although the winding speed is variable depending on the production speed, it is preferably 1 m / min or less in order to prevent the winding edge of the multilayer substrate from being displaced when the winding tension is 100 N / m or less. More preferably, it is 0.2 m / min or less.

  The term “winding misalignment” as used herein means that the position of the end portion of the multilayer substrate wound around the take-up roll 32 is not fixed and is wound while being shifted. When the deviation width is large, scratches are generated on the element substrate surface, the commercial value of the organic EL element substrate is lost, and the production yield is lowered.

  The winding deviation is preferably less than 3 mm, more preferably less than 0.5 mm.

  Further, the winding tension can be adjusted by controlling the torque of the shaft of the winding roll 32. When the winding tension is 100 N / m or more, winding tightening occurs remarkably, peeling and deformation of the sealing material occur, and the sealing performance is remarkably lowered. In the winding before the adhesive layer is cured, the adhesive layer is likely to be deformed. Therefore, by winding up the multilayer substrate with a tension of 100 N / m or less, peeling and deformation of the sealing material are suppressed, and deterioration of the organic EL element performance such as deterioration of sealing performance and light emitting defects is prevented. Can do.

  When the surface of the element substrate or the separator film is slippery and it is difficult to wind up with the end portions of the multilayer substrate, a flange that regulates the position of the end portions of the multilayer substrate may be installed on the winding roll 32. .

[Curing process]
The curing step is a step of curing the adhesive after the step of winding the multilayer substrate 13 in a state where the adhesive is not cured under vacuum pressure.

  The curing of the adhesive is a process in which the viscosity of the adhesive constituting the adhesive layer is set to 5000 Pa · s or more using a curing means. The viscosity of the cured adhesive layer is preferably 10,000 Pa · s or more.

  When the adhesive that constitutes the adhesive layer is a thermosetting resin or a photocurable resin, the adhesive is cured after the bonding step, so that the form of the organic EL structure is fixed and stable. It is necessary to make it. By curing the adhesive, the element substrate and the sealing member are firmly bonded, and the organic EL structure is hermetically sealed between both the substrates, so that an organic EL element having excellent durability can be obtained.

  When the adhesive composing the adhesive layer is a thermosetting resin, it is preferable that the adhesive curing means in the curing step is heating. When the adhesive constituting the adhesive layer is a photocurable resin, the curing means for the adhesive in the curing step is preferably light irradiation.

  In a hardening process, it is preferable to isolate | separate from the formation process or the bonding process of an organic EL structure from a viewpoint that the organic EL element performance by the outgas which generate | occur | produces by the heat and light irradiation which are used with a hardening means prevents deterioration. A method for separating the curing process and the organic EL structure forming process or the bonding process is not particularly limited. However, when a multi-layer substrate is continuously transferred using a plurality of chambers, the range in which each process can be performed is the length of the chamber. It will be limited. In addition, it is necessary to open and close the chamber at any time, and there is concern about environmental degradation or a decrease in vacuum in the chamber. Therefore, from the viewpoint of improving productivity, the multilayer substrate can be wound in the chamber where the bonding process has been performed. preferable.

  Examples in which the effects of the present invention are confirmed will be described below. In addition, this invention is not limited to this Example.

Example 1
[First feeding process]
At the first feeding portion, a polyethylene terephthalate film (manufactured by Teijin DuPont Films, Ltd., hereinafter abbreviated as PET as appropriate) having a length of 30 m, a width of 1000 mm, and a thickness of 100 μm was fed as an element substrate.

  The element substrate discharged from the first feeding portion was subsequently transferred to the organic EL structure forming portion.

[Organic EL structure forming step]
The manufacturing process of the organic EL element was performed in a chamber having a vacuum pressure of 10 ⁻⁴ Pa or less.

(Element board preparation)
The entire surface of the flexible substrate on the side on which the first electrode is formed is continuously formed on the element substrate from SiOx by using an atmospheric pressure plasma discharge treatment apparatus having the configuration described in Japanese Patent Application Laid-Open No. 2004-68143. An inorganic gas barrier film was formed to a thickness of 500 nm. Thus, a gas barrier flexible substrate having an oxygen permeability of 0.001 ml / m ² / day or less and a water vapor permeability of 0.001 ml / m ² / day or less was produced.

(Formation of the first electrode)
A first electrode made of ITO (indium tin oxide) was formed to a thickness of 120 nm on a gas barrier flexible substrate under a vacuum condition of 5 × 10 ⁻¹ Pa by sputtering.

(Formation of hole transport layer)
N, N′-diphenyl-N, N′-m-tolyl-4,4′-diamino- as a hole transport layer forming material under vacuum conditions of 5 × 10 ⁻⁴ Pa by vapor deposition (vapor phase deposition) 1,1′-biphenyl was deposited on the first electrode to form a 30 nm thick hole transport layer.

  Then, a light emitting layer, an electron injection layer, and a second electrode were laminated on the formed hole transport layer according to the following conditions to produce an organic EL structure, which was wound into a roll.

(Formation of light emitting layer)
CBP as a host compound and Ir (ppy) ₃ as a light emitting material were laminated by a co-evaporation method so that the doping concentration was 6% and the thickness was 40 nm. Note that although a material having green light emission is used in this embodiment, a white organic EL element can be manufactured by further stacking layers using blue, red, and light emitting materials.

(Formation of electron injection layer)
Subsequently, LiF was deposited on the light emitting layer as a material for forming an electron injection layer under a vacuum condition of 5 × 10 ⁻⁴ Pa on the formed light emitting layer by a vapor deposition method (vapor phase deposition method). An electron injection layer (LiF layer) was formed.

(Formation of second electrode)
Subsequently, aluminum is used as the second electrode forming material on the formed electron injection layer by vapor deposition (vapor phase deposition method), and is deposited on the electron injection layer by mask pattern film formation so as to have an extraction electrode. A second electrode layer having a thickness of 100 nm was formed to produce an organic EL structure.

  Mask pattern film formation was performed so that the hole transport layer, the light emitting layer, and the electron injection layer were disposed within a range of 48 mm × 48 mm. The mask pattern was formed such that the first electrode (anode) was 48 mm × 54 mm and the second electrode (cathode) was 50 mm wide × 54 mm long.

  The element board | substrate with which the organic EL structure discharged | emitted from the organic EL structure formation part was formed was continuously conveyed to the bonding part.

[Second feeding process]
At the second feeding portion, a sealing member having a two-layer structure of a polyethylene terephthalate film (made by Teijin DuPont Films Ltd.) having a thickness of 50 μm and an aluminum foil made of a conductive material having a thickness of 7.0 μm, and a thickness of 20 μm A separator film having a length of 30 m, a width of 1000 mm, and a thickness of 100 μm on which a sealing material composed of an adhesive layer using a thermosetting adhesive (1600 series manufactured by Three Bond Co., Ltd.) was formed was drawn out.

[Bonding process]
The bonding of the organic EL structure and the sealing material is a structure in which the organic EL structure and the sealing material are stacked and adhered between a pair of adhesion rolls. The organic EL structure formed into a film of 48 mm × 48 mm and the adhesive layer of the sealing material processed to 50 mm × 50 mm are bonded with a bonding roll in a chamber having a vacuum pressure of 10 Pa or less, and the sealing width An organic EL element having a thickness of 2 mm was formed. The sealing width is the distance from the end of the organic functional layer (hole transport layer, light emitting layer, electron injection layer) to the end of the sealing material in the element substrate, and the organic function directly under the sealing material. Since the layer does not exist, the invasion is suppressed except for moisture transmitted between the element substrate and the sealing member.

  A pasting part has an upper pasting roll and a lower pasting roll. It has a structure in which the bonding rolls rotate while contacting and pressing at a constant pressure so that the element substrate passing between the upper and lower bonding rolls and the sealing material can be uniformly and continuously pressed. The surface of the bonding roll was rubber-lined, the rubber hardness (JIS K 6253) was 70 degrees, and the outer diameter was φ100 mm.

  The bonding part was temperature-controlled so that the bonding roll temperature was 30 ° C. both above and below, and the pressure of the bonding roll was adjusted to 0.3 MPa as the surface pressure applied to the organic EL structure. The conveyance speed of the bonding part was 1 m / min. The surface pressure was measured using a Fuji film prescale (for ultra-low pressure) and a roll at normal temperature and humidity (23 ° C., relative humidity 50%).

  The multilayer substrate on which the organic EL structure in which the sealing material discharged from the bonding part is adhered is formed is continuously conveyed to the winding part.

[Winding process]
The multilayer substrate was wound up by controlling the torque of the winding roll shaft so that the vacuum pressure was 10 Pa or less and the winding tension was 100 N / m.

[Curing process]
The wound multilayer substrate is taken out from the chamber having a vacuum pressure of 10 Pa or less and cured in a thermosetting transport furnace. The inside of the thermosetting furnace whose temperature in the furnace was raised to 100 ° C. was transported at a speed of 1 m / min for 2 hours to perform thermosetting treatment.

  After performing the thermosetting process, the long multilayer substrate was cut to manufacture each organic EL element.

<< Example 2 >>
An organic EL element 2 was produced under the same conditions as in Example 1 except that the winding tension was 50 N / m.

Example 3
An organic EL device 3 was produced under the same conditions as in Example 1 except that the winding tension was 10 N / m.

Example 4
An organic EL element 4 was produced under the same conditions as in Example 1 except that the winding tension was 8 N / m.

Example 5
An organic EL element 5 was produced under the same conditions as in Example 1 except that the winding tension was 200 N / m.

Example 6
An organic EL element 6 was produced under the same conditions as in Example 1 except that the winding tension was 300 N / m.

≪Comparative example 1≫
In the chamber in which the organic EL structure and the sealing material were bonded under the same conditions as in Example 1 to form a multilayer substrate, and after discharging from the bonding part, the winding process was not performed and the bonding process was performed. The curing treatment was performed under the same conditions as in Example 1. After the curing treatment, the multilayer substrate was wound up under the same conditions as in Example 2 in the chamber subjected to the curing treatment. Thereafter, the wound multilayer substrate was taken out of the chamber, and the long multilayer substrate was cut under the same conditions as in Example 1 to manufacture each organic EL element 7.

≪Comparative example 2≫
An organic EL element 8 was produced under the same conditions as in Comparative Example 3, except that the winding tension after the curing treatment was 10 N / m.

[Evaluation]
Each organic EL element is allowed to stand for 500 hours in a thermo-hygrostat (manufactured by ESPEC, PHP-3 type) maintained at an atmospheric temperature of 85 ° C. and an atmospheric humidity of 85%. The light emission defect distance of EL was measured, and the penetration of moisture that penetrates between the element substrate and the sealing member and the sealing performance in the organic EL sealing structure having a sealing width of 2 mm were evaluated.

Evaluation rank ◎: Probability of occurrence of light emission defects of 1 mm or more Less than 10% ○ Probability of occurrence of light emission defects of 1 mm or more 10% or more but less than 20% × Probability of occurrence of light emission defects of 1 mm or more 20% or more [Evaluation]
In each organic EL element after the adhesive curing process, the occurrence of indentation defects caused by the peeling of the sealing material that occurs when the multilayer substrate is wound up in a state where the adhesive is not cured, and the pressure due to the winding up Probability was evaluated.

Evaluation rank A: Defect occurrence rate less than 1%
○: Defect occurrence rate 1% to less than 3% ×: Defect occurrence rate 3% or more [Evaluation]
When taking out the wound multilayer substrate from the chamber having a vacuum pressure of 10 Pa or less, the winding deviation of the multilayer substrate was evaluated. Winding deviation is measured by taking the half of the width of the multilayer substrate perpendicular to the winding direction as the initial winding center, and measuring the distance from the winding center to the end of the multilayer substrate actually wound. The deviation from the ideal value (a value obtained by halving the width of the multilayer substrate perpendicular to the winding direction) was evaluated.

Evaluation rank ◎: Winding deviation less than 0.5 mm ○: Winding deviation 0.5 mm to less than 1 mm △: Winding deviation 1 mm to less than 3 mm ×: Winding deviation 3 mm or more

  When the organic EL elements 1 to 6 wound at 100 N / m or less are wound on the multilayer substrate in a state where the adhesive is not cured under vacuum pressure, the occurrence of light emitting defects and the occurrence of defects such as peeling and indentation and winding It was confirmed that deviation was suppressed and stable organic EL element performance and organic EL element quality were obtained.

  It was confirmed that the organic EL elements 7 and 8 in which the multilayer substrate was wound up in the vacuum chamber after curing the adhesive were caused to emit light defects and defects. The effectiveness of the present invention was confirmed.

DESCRIPTION OF SYMBOLS 1 Organic EL element 2 Organic EL structure 3 Sealing material 11 1st electrode 12 Organic functional layer 13 2nd electrode 14 Adhesive layer 15 Sealing member 16 Element board | substrate 17 Separator film 20 1st delivery part 21 1st delivery roll 22 1st guide roller 23 2nd feeding part 24 2nd feeding roll 25 2nd guide roller 26 Organic EL structure forming part 27 Laminating part 28 Laminating roller 29 Multilayer substrate 30 Winding part 31 Winding guide roller 32 Winding roll

Claims (2)

In the manufacturing method of an organic electroluminescence device using the roll-to-roll method, in vacuum Ji Yanba,
A sealing material formed on a long flexible substrate in the order of at least a sealing member and an adhesive layer;
After laminating at least the anode, the organic functional layer and the organic electroluminescent structure formed on the long element substrate,
Ri preparative winding and pasted the said sealing material and said organic electroluminescent structure,
Then, the said adhesive bond layer is hardened outside the said vacuum chamber, The manufacturing method of the organic electroluminescent element characterized by the above-mentioned .   The method of manufacturing an organic electroluminescence element according to claim 1, wherein the winding is performed with a tension of 100 N / m or less.

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