JP2015111508A - Sealing film for organic electroluminescence, manufacturing method thereof, and manufacturing method of organic electroluminescent device by use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a sealing film which is arranged so that its production process is not restricted by a pot life, the damage to a sealing base, the delamination thereof and the like are reduced, and its sealability can be kept even under a condition such that the pressure is changed; a method for manufacturing such a sealing film; and a method for manufacturing an organic EL device by which the formation of a part inoperable to emit light can be suppressed.SOLUTION: A sealing film for organic electroluminescence comprises: a first flexible base; a second flexible base; and a seal material located between the first and second flexible bases and having a sealing base and an adhesive layer. The seal material is patterned; and at least one of the first and second flexible bases has a communicating hole corresponding to an opening formed by patterning the seal material.

Description

  The present invention relates to a sealing film for organic electroluminescence (hereinafter also referred to as “organic EL”), a method for producing the same, and a method for producing an organic electroluminescent element using the same.

  In an organic EL element, a light emitting layer of an organic compound (hereinafter also referred to as an organic light emitting layer or simply a light emitting layer) is sandwiched between two electrodes, a first electrode (anode) and a second electrode (cathode), on a substrate such as glass. The organic light emitting layer emits light by arranging the organic EL structure having the structure and supplying a current between the anode and the cathode.

  The organic light-emitting layer constituting the organic EL element is easily affected by moisture and oxygen, and if left in the air and moisture and oxygen enter the organic EL element, quality degradation such as generation of non-light-emitting parts in the organic EL element Occurs. For this reason, the manufacturing process of the organic EL element is performed under vacuum, and a process of forming a sealing layer on the organic EL structure for reducing the influence of the outside world called sealing is provided.

  In recent years, with the expansion of applications of organic EL elements, etc., a thin organic light-emitting layer is formed on a flexible substrate such as a resin film, and a flexible high barrier film or a sealing substrate such as a metal foil is used. Solid-sealed organic EL elements that are sealed by bonding with an adhesive have appeared.

  In addition, as a manufacturing method for efficiently mass-producing organic EL devices at low cost, an organic EL structure including a light emitting layer and an electrode is patterned to form an organic EL structure while continuously running a flexible substrate. A method of forming the body has become possible.

  Pattern formation here means forming an object into a predetermined shape, and when processing the object into a predetermined shape is called pattern processing. The object processed is removed from the region processed to obtain a predetermined shape (patterned region), and an opening is formed.

  By using pattern formation and pattern processing in the manufacturing process, it is possible to continuously manufacture a product having a predetermined shape, which has an advantage of improving productivity.

  Also in the solid sealing type organic EL element, in order to improve the productivity, the sealing base material uniformly formed on the surface of the flexible base material is previously patterned in a shape corresponding to the organic EL structure. Processing and bonding with an organic EL structure has been proposed. For example, in Patent Document 1, in a method for manufacturing a solid-sealing type organic EL element, a pre-patterned sealing base material on a flexible base material and an organic material formed on the flexible base material are disclosed. The manufacturing method of the organic EL element which laminates | stacks an adhesive material layer on an organic EL structure body, and is bonded is described.

JP 2004-303528 A

  However, in the manufacturing method described in Patent Document 1, after patterning the sealing substrate formed on the flexible substrate, the flexible substrate is in a state where the surface of the sealing substrate is exposed. It is wound up. For this reason, the surface of the sealing substrate is damaged or deformed by the contact of the flexible substrate overlapped by winding, or pressed by the sealing substrate overlapped by winding, or peeled off from the flexible substrate. May occur. Damage, peeling, etc. of the sealing substrate cause a decrease in sealing performance.

In addition, since the adhesive has a usable time capable of maintaining a viscosity and a state capable of being bonded, an adhesive layer is formed on the organic EL structure, and the sealing substrate is surface-adhered on the adhesive layer. In the manufacturing method, the process of forming the adhesive layer on the organic EL structure and the process of laminating the sealing substrate are limited to the usable time of the adhesive constituting the adhesive layer, thereby improving productivity. There is a problem that there is a limit.
When the usable time of the adhesive constituting the adhesive layer formed on the organic EL structure is over, it is necessary to give energy to obtain a viscosity and a state that can be adhered again, and the light emitting performance of the organic EL structure It becomes a factor to reduce.

  In order to solve this problem, an adhesive layer is formed on a sealing substrate, flexible substrates are provided on both sides of the adhesive layer and the sealing substrate, and a sealing film is formed. The base material and the adhesive material layer can be wound up without being exposed, and the adhesive material is pressed by the contact of the flexible base material overlapped by winding or the sealing base material and the adhesive material layer overlapped by winding. Since damage or deformation of the layer or the sealing substrate, peeling from the flexible substrate, and the like are suppressed, it is possible to prevent a decrease in sealing performance. Therefore, generation of a non-light emitting portion is suppressed in the organic EL element, and uniform light emission in the surface of the organic EL element can be obtained.

  In addition, since the adhesive layer is provided on the sealing substrate, the manufacturing process is not limited by the usable time of the adhesive, and an improvement in productivity is expected.

  However, when a sealing film is produced under atmospheric pressure, the sealing substrate whose surface is exposed after patterning the sealing substrate and the adhesive layer formed on the flexible substrate in the process. Since a flexible base material needs to be bonded to the material surface or the adhesive material layer surface, gas is confined in the opening formed by patterning the sealing base material and the adhesive material layer. When the sealing film is wound in a state having a gas in the sealing film and put into a vacuum for bonding with the organic EL structure, the gas confined in the opening formed by the pattern processing expands. Deformation of the sealing substrate or adhesive layer or peeling from the flexible substrate occurs, causing defects such as laminating wrinkles and bending when bonded to the organic EL element, resulting in a decrease in sealing performance. It was.

  The present invention has been made in view of the above problems and situations, and the solution is that the production process is not limited to the pot life, and damage or peeling of the sealing substrate is suppressed, It is to provide a sealing film that maintains sealing performance even under pressure fluctuation conditions and a method for manufacturing the same, and a method for manufacturing an organic EL element in which generation of non-light-emitting portions is suppressed.

  The object of the present invention is achieved by the following constitution.

1. A sealing film comprising a sealing material having a sealing substrate and an adhesive layer between a first flexible substrate and a second flexible substrate,
The sealing material is patterned,
At least one of the first flexible substrate and the second flexible substrate is provided with a communication hole corresponding to an opening formed by patterning a sealing material. the film.

2. A method for producing a sealing film comprising a sealing material having a sealing base material and an adhesive layer between at least a first flexible base material and a second flexible base material,
at least,
A step of patterning the sealing material;
Forming a communication hole corresponding to an opening formed by pattern processing of the sealing material in at least one of the first or second flexible substrate;
The manufacturing method of the sealing film characterized by including.

  3. 3. The method for producing a sealing film according to 2, wherein the step of forming the communication hole and the step of patterning the sealing material are performed simultaneously.

4). A sealing film in which a first flexible base material, a sealing material having a sealing base material and an adhesive layer, and a second flexible base material are arranged in this order, at least an anode, an organic light emitting layer, and a cathode In the manufacturing method of an organic electroluminescence element formed by bonding to an organic electroluminescence structure having,
A step of patterning the sealing material;
Forming a communication hole corresponding to an opening formed by pattern processing of the sealing material in at least one of the first or second flexible substrate;
Peeling the first flexible substrate from the sealing film;
The manufacturing method of the organic electroluminescent element characterized by including the process of bonding the said organic electroluminescence with the adhesive material layer surface from which the 1st or 2nd flexible base material was peeled.

5. 5. The organic electroluminescent device according to 4 above, wherein the step of bonding the organic electroluminescent structure to the adhesive layer surface from which the first or second flexible base material has been peeled is performed under vacuum. Manufacturing method.
6). 6. The method for producing an organic electroluminescent element according to 4 or 5, wherein the step of forming the communication hole and the step of patterning the sealing material are performed simultaneously.

According to the present invention, the adhesive layer is formed on the sealing substrate and patterned, the flexible substrate is provided on both surfaces of the adhesive layer and the sealing substrate, and at least one of the flexible substrates By having a communication hole that allows ventilation, the production process is not limited by the usable time of the adhesive, and damage or peeling of the sealing substrate is suppressed and even under conditions where the pressure fluctuates A sealing film that retains sealing performance and a method for producing the same can be provided.
Moreover, the manufacturing method of the organic EL element by which generation | occurrence | production of the non-light-emission part was suppressed can be provided by using the sealing film of this invention.

Schematic sectional view showing an example of the configuration of an organic EL element Outline diagram showing examples of communication holes Schematic diagram showing an example of patterned sealing film Schematic showing an example of the manufacturing method of the sealing film Schematic which showed an example of the manufacturing method of the organic EL element using a sealing film

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Modes for carrying out the present invention will be described below, but the present invention is not limited to the embodiments described below, and the embodiments are arbitrarily changed within the scope of the present invention. Is possible.

<Organic EL device>
Below, the structure of the organic EL element of this invention is demonstrated in detail using FIG.

  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 invention, the organic EL structure 2 is sandwiched by the 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 sealed and sealed.

  Here, the sealing material 3 has the sealing base material 15 with the adhesive layer 14 formed on the surface, and seals the organic EL structure by closely adhering to the organic EL structure. ing.

  The organic EL structure 2 is formed on at least the first electrode 11 formed on the element substrate 16, the organic light emitting layer 12 formed on the first electrode 11 and including the light emitting layer, and the organic light emitting 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.

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

<Sealing film>
Below, the structure of the sealing film of this invention is demonstrated in detail.

  The sealing film of this invention is equipped with the sealing material which has the sealing base material and adhesive layer which were patterned between the 1st flexible base material and the 2nd possibility base material at least, and is 1st. Alternatively, a communication hole is formed in at least one of the second flexible base materials. The sealing material is protected or supported by the first or second flexible substrate.

  FIG. 2 is a schematic diagram showing an example of the communication hole. In the present invention, the communication hole refers to a structure that allows at least one of the first flexible substrate 4 or the second flexible substrate 5 to vent gas. In FIG. 2, the arrows mean gas ventilation.

  The shape of the communication hole 8 is not particularly limited, and any structure may be used as long as the gas in the opening 9 formed in the sealing material 3 can be vented by pattern processing. For example, as shown in FIG. 2 (a), linear elongated holes in contact with the opening 9 of the sealing material by pattern processing or closed pores as shown in FIG. 2 (b) are continuously arranged. A curved communication hole formed by connecting them spatially can be mentioned. Since the gas can be easily ventilated, a linearly formed communicating hole is preferable.

  Any method may be used for forming the communication hole, for example, a method of forming by mechanical or physical processing such as pressing or laser processing of a convex member, or chemical processing such as decomposition or corrosion. Thus, a method of forming a communication hole can be used, and any of these methods can be used in combination.

  Hereinafter, each part which comprises the sealing film which concerns on this invention is demonstrated. However, the structure of the sealing film is not limited to the following contents.

(Encapsulant)
The sealing material of this invention is demonstrated.

  The sealing material includes at least a sealing base material and an adhesive layer, and is used, for example, to block or protect the organic EL structure or the like from the external environment.

  In the present invention, the sealing material is patterned into a shape suitable for forming an organic EL element. The shape for processing the sealing material is preferably a size including the organic EL structure formed on the element substrate, and part of the first electrode and the second electrode part.

  The pattern processing method is not particularly limited. For example, a method of forming by mechanical or physical processing such as pressing processing or laser processing of a convex member, or a method of pattern processing by chemical processing such as decomposition or corrosion can be used, Any one of these methods can be used in combination.

  Specific examples of the pattern processing include mechanical processing using a punching blade, thermal processing using a laser, a photolithography method, an etching method, and the like. The blade shape of the punching blade is not specified, and mechanical processing with other blades can be used. The pattern processing will be described in detail below.

  Pattern processing can be performed including not only the sealing material but also the first and / or second flexible base material bonded to the sealing material.

  In the pattern processing method of the present invention, the method of pattern processing from the sealing material surface including the first or second flexible base material bonded to the sealing material is fully cut and sealed from the sealing material surface. The method of patterning only the material is called half cut.

  By full-cutting, it becomes possible to simultaneously perform the step of patterning the sealing material and the step of forming the communication hole in the first or second flexible substrate. By simultaneously performing the process of patterning the sealing material and the process of forming the communication hole in the first or second flexible substrate, and reducing the number of processes, the manufacturing cost of the sealing film can be suppressed. . Since the communication hole formed by the full cut communicates with the opening formed by patterning, the air permeability is excellent.

  The half-cut may be a process that does not penetrate the first or second flexible substrate, and a method of patterning to the extent that it does not penetrate the first or second flexible substrate is also called a half-cut.

  FIG. 3 is a schematic diagram illustrating an example of a patterned sealing film, and illustrates a surface of the patterned sealing film and a cross section in the thickness direction.

  The sealing material 3 in FIG. 3 is patterned into a predetermined shape (rectangular in FIG. 3) by half cut and full cut.

  The opening 9 formed by the pattern processing of FIG. 3 refers to a region processed to make the sealing material 3 into a predetermined shape. Specifically, the opening 9 is formed by fully cutting the sealing film. Part of the sealing material 3 and the first flexible substrate 4 formed by half-cutting the sealing film 3 and the opening (full cut region 7) of the first flexible substrate 4 and the sealing film. The opening (half-cut region 6).

  The communication hole 8 through which gas can be vented is included in the full cut region 7. Therefore, it is desirable that the full cut area 7 and the half cut area 6 are connected.

  Although the communication hole is not particularly limited, it can be produced by various combinations of intervals, density, surface area and the like in order to obtain desired physical properties.

  FIG. 4 is a schematic view showing an example of a method for producing a sealing film. Although an example of the manufacturing method of the sealing film at the time of performing simultaneously the process of pattern-processing to a sealing material and the process of forming a communicating hole in the 1st flexible substrate below, the present invention is the following contents. It is not limited at all.

  In FIG. 4B, the first flexible base material 4 in which the adhesive layer 14 and the sealing base material 15 are laminated is full cut and half cut using the punching blade 20, thereby patterning the sealing material. The step of processing and the step of forming the communication hole in the first flexible substrate are performed simultaneously.

  FIG. 4C shows a process of bonding the second flexible substrate 5 to the surface of the sealing substrate 15 after full cutting and half cutting using the punching blade 20. The communication hole 8 formed in the first flexible substrate 4 by the full cut enables ventilation of the opening 9 formed by pattern processing.

(Sealing substrate)
The sealing substrate is preferably flexible and has mechanical strength, gas barrier properties against water vapor and oxygen, light transmittance, and the like.

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

  These materials may be used alone or as a multi-layered sheet by mixing, bonding, extruding lamination, co-extrusion, etc. It is possible to use a film formed with a gas barrier film having 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.

  Although the thickness of the sealing substrate is not particularly limited, it is preferably 10 μm or more and 300 μm or less in consideration of molding processability. In addition, the thickness of the sealing base material here can be measured using a micrometer.

When using the above thermoplastic resin or curable resin as the sealing substrate, a gas barrier layer may be formed on the sealing substrate by vapor deposition or coating. 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 , SixOy (x = 1, y = 1.5 to 2.0), Ta ₂ O ₃ , ZrN, SiC, TiC, PSG, Si ₃ N ₄ , SiN, Examples thereof include single crystal Si and amorphous Si. 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 method for laminating the material of the metal foil is not particularly limited, but it is desirable to use a laminating method that provides high productivity.

  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)
In the present invention, the adhesive layer is a layer that protects the organic EL structure by bonding and fixing the element substrate, the organic EL structure formed on the element substrate, and the sealing substrate.

  The adhesive layer is formed on the surface of the sealing substrate. And an organic EL element can be sealed or sealed by bonding in the surface in which the adhesive material layer was formed on the sealing base material, and the surface in which the organic EL element structure of the element substrate was formed.

  In the present invention, the resin constituting the adhesive layer is a curable resin. 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.

  As a method for forming an adhesive layer with a curable resin, depending on the type and viscosity of the curable resin, gravure coating, roll coating, bar coating, die coating, knife coating, hot melt coating, dipping, spin coating, spray coating, etc. The printing method such as coating method or screen printing can be used. The curable resin at the time of forming the adhesive layer may be a low-viscosity liquid or a high-viscosity paste.

  The thickness of the adhesive layer is preferably 1 μm to 100 μm from the viewpoint of sealing performance and panel thinning. In order to remove moisture contained in the adhesive layer, a desiccant such as barium oxide or calcium oxide may be mixed in the adhesive layer.

  It is preferable to add a filler to the curable resin 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 strength, the thickness of the adhesive material 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.

(First and second flexible substrates)
In the present invention, the first or second flexible substrate is not particularly limited as long as it has flexibility, but it is flexible from the viewpoint of supporting or protecting the adhesive layer or the sealing substrate. It is desirable to be a film. 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 same material as the sealing substrate can also be used. By using the same material as the sealing material substrate, the manufacturing cost of the sealing film can be suppressed.

  Production of a sealing film by a roll-to-roll method that uses a long and flexible film as the first and second flexible substrates to produce a flexible film while continuously running Is possible.

  The material used for the first or second flexible substrate may be used alone, or by mixing, bonding, extrusion laminating, co-extrusion, etc., as necessary. It can be used as a combined multilayer long sheet. 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.

  Moreover, you may provide the adhesion layer for bonding with a sealing material on a 1st or 2nd flexible base material. The pressure-sensitive adhesive layer formed on the first or second flexible substrate is not particularly limited, but it is preferable to use an acrylic resin from the viewpoint of production cost and ease of handling.

  When the first or second flexible substrate has a multilayer structure including an adhesive layer, a part of the first or second flexible substrate may be peeled between the adhesive layer or the layer in contact with the adhesive layer. Is possible. When the first or second flexible substrate has a multilayer structure, the roll or the sealing film can be protected when the sealing film is manufactured by a roll-to-roll method.

<Organic EL structure>
(Element board)
Here, the element substrate of 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. Moreover, when transmitting the emitted light from the sealing substrate, materials other than the transparent resin can be selected. For example, copper, copper alloy, aluminum, aluminum alloy, gold, nickel, titanium, stainless steel, tin, etc. A metal 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 μm to 500 μm in consideration 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 material layer of the sealing base 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 more gas barrier layers are formed between the element substrate and the organic 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 layer. The order in which the inorganic layer and the organic layer are stacked is not particularly limited, but it is preferable to stack the layers alternately a plurality of times.

(First electrode)
The first electrode (anode) is an electrode film that supplies (injects) holes to the organic light emitting 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 light emitting layer)
Various organic light-emitting layers constituting the organic light-emitting layer will be described below, and since specific materials of each organic light-emitting layer of these organic light-emitting layers can be applied with known materials, 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 light emitting layer, the description thereof is omitted.

A preferred stacking example of the organic light emitting layer is 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 / hole blocking layer / electron transport layer (4) Hole transport layer / Light emitting layer / hole blocking layer / electron transport layer / electron injection layer (cathode buffer layer) (5) hole injection layer (anode buffer layer) / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / Electron injection layer (6) 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.

<Method for producing organic EL element>
Although the manufacturing method of the organic EL element using a sealing film is demonstrated below, this invention is not limited to the following contents at all.

  FIG. 5 shows an example of a method for producing an organic EL element using a sealing film.

  The sealing film 10 is unwound from the unwinding roll 23, and the first flexible substrate 4 of the sealing film 10 is peeled off, and the sealing material 3 having a predetermined shape is left by pattern processing, and the adhesive layer 14 is left. And the unnecessary part of the sealing base material layer 15 is peeled from the second flexible base material 5. Bonding with the organic EL structure 2 formed so that the adhesive layer surface of the sealing material 3 from which the first flexible base material 4 has been peeled is periodically arranged on the element substrate 16 at intervals. By doing so, an organic EL element is manufactured.

  The manufacturing process 28 of the organic EL structure and the process of bonding the sealing material 3 to the organic EL structure 2 are performed under vacuum 27. Accordingly, when the organic EL element 1 is manufactured by putting the sealing film 10 manufactured under atmospheric pressure into the vacuum 27, the gas confined in the opening 9 formed by patterning is discharged through the communication hole 8. The

In the present invention, although the vacuum pressure is not particularly limited, an organic EL structure formed on the element substrate under a vacuum of 1 × 10 ⁻⁴ Pa or less, and a sealing material for a sealing film manufactured under atmospheric pressure, Are bonded together under a vacuum of 10 Pa or less to produce an organic EL element, whereby the sealing material is prevented from being damaged or peeled off, thereby improving the organic EL element performance and productivity.

  The means for pasting is not particularly limited. Various means such as flat plate bonding with a bonding roll, diaphragm bonding, and the like can be used. In this embodiment, a thermocompression bonding type roll laminate is used as a typical bonding means.

  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.

  The manufacturing process of the sealing film was performed under atmospheric pressure.

<Preparation of sealing film no. 1 (comparative example)>
(Separator film (first flexible substrate) and sealing material creation step)
Polyester adhesive is used as the sealing substrate, a polyethylene terephthalate film (made by Teijin DuPont Films Co., Ltd.) with a thickness of 50 μm, and an aluminum foil of a conductive material with a thickness of 7.0 μm as the sealing substrate. The sealing base material of 2 layer structure was produced by joining by the dry-laminating method. Then, a sheet-like thermosetting adhesive (1600 series manufactured by ThreeBond Co., Ltd.) is bonded to the aluminum foil surface as an adhesive layer by a dry laminating method, and the adhesive layer having a thickness of 20 μm is bonded to the sealing substrate. It was formed on the entire upper surface. Furthermore, as a separator film (corresponding to the first flexible substrate), a polyethylene terephthalate film (manufactured by Teijin DuPont Films Co., Ltd.) having a length of 30 m and a thickness of 100 μm is used, and is pasted on the adhesive layer surface by a dry laminating method. To form a long roll.

(Process for pattern processing)
As a punching blade, a pinnacle blade with a double-edged blade in which a rectangular shape with a blade height of 1.5 mm and a 50 mm × 50 mm rectangular array is arranged at a pitch of 80 mm is set on the sealing substrate side of the film. In the anvil roll disposed on the material separator side, the sealing substrate and the adhesive layer are formed in the rectangular shape while controlling the gap between the punching blade and the anvil roll so that the separator blade pierces the separator film by about 20 μm. The pattern was processed.

(Lamination process of transfer film (second flexible substrate))
As a transfer film (corresponding to the second flexible substrate), a polyethylene terephthalate film (Panac GN series) with a thickness of 38 μm with an acrylic adhesive formed on the entire surface of one side is used to pattern the transfer film. The sealing film no. In which the sealing material is disposed between the separator film and the transfer film by bonding to the sealing substrate side of the sealing material by the dry lamination method. 1 was produced.

<Sealing film no. 2 Production (Invention)>
As a punching blade, a rectangular shape with a blade height of 1.5 mm and a 50 mm × 50 mm array with a rectangular center position of 80 mm pitch, the blade height at the four corners of the rectangle is 1.6 mm over 1 mm from front to back. The pinnacle blade of both blades formed in the above is set on the sealing substrate side of the formed film, and an anvil roll disposed on the substrate separator side has a blade with a blade height of 1.5 mm on the separator film. The sealing substrate and the adhesive layer are patterned into the above rectangular shape while controlling the gap between the punching blade and the anvil roll so that the blade with a blade height of 1.6 mm penetrates the separator film and penetrates about 20 μm. Other than that, the sealing film no. 1 under the same conditions as for the sealing film no. 2 was produced.

<Sealing film no. 3 (Invention)>
Using a YVO ₄ laser with a wavelength of 532 nm and a CO ₂ laser with a wavelength of 9.3 μm, the sealing material is arranged in a rectangular shape of 50 mm × 50 mm and the rectangular center positions are arranged at a pitch of 80 mm. Pattern processed. The rectangular corners are 1 mm in length, and the separator film, the adhesive, and the sealing substrate are penetrated, and the other rectangular parts are sealed so that the laser processing grooves are formed in the separator film at 20 μm. The material and the adhesive material layer are patterned into the rectangular shape, otherwise the sealing film no. 1 under the same conditions as for the sealing film no. 3 was made.

<Evaluation>
Sealing film no. 1 to no. 3 is placed in a vacuum chamber evacuated to 10 Pa each, and the floating of the sealing substrate from the transfer film is generated, and further, the element substrate on which the organic EL structure is formed in vacuum The sealing film was bonded with a lamination roll having a surface temperature of 90 ° C., and the occurrence of bonding wrinkles was evaluated.

Evaluation rank ◎: Defect occurrence rate less than 1%
○: Defect occurrence rate 1% to less than 3% ×: Defect occurrence rate 3% or more

  A sealing film sample having a communication hole formed in the first flexible substrate, no. 2 and no. 3 is stable when the sealing film is put under vacuum and the generation of peeling of the sealing material from the second flexible substrate and the generation of wrinkles when the sealing material is bonded to the element substrate are suppressed. It was confirmed that the obtained bonding performance was obtained.

  Sample of sealing film in which communication holes were not formed in the first flexible substrate no. 1 was confirmed that when the sealing film was put under a vacuum of 10 Pa or less, peeling of the sealing material from the second flexible base material and generation of wrinkles when the sealing material was bonded to the element substrate were confirmed. It was. The effectiveness of the present invention was confirmed.

<Organic EL element no. 4-1 Production>
The manufacturing process of the organic EL element was performed under a high vacuum of 1 × 10 ⁻⁴ Pa or less.

(Formation of organic EL structure)
[Preparation of element substrate]
As an element substrate, a polyethylene terephthalate film (manufactured by Teijin DuPont Films Co., Ltd., hereinafter abbreviated as PET as appropriate) having a length of 30 m, a width of 1000 mm, and a thickness of 100 μm is prepared, and the entire surface of the element substrate on the side where the first electrode is formed. An inorganic gas barrier film made of SiOx was continuously formed on the element substrate so as to have a thickness of 500 nm using an atmospheric pressure plasma discharge treatment apparatus having a configuration described in JP-A-2004-68143. Thus, a gas barrier element 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.

  Next, an organic EL structure was produced on the element substrate by the following procedure.

[Formation of 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 agent and Ir (ppy) ₃ as a dopant agent were laminated by a co-evaporation method so that the doping concentration was 6% and the thickness was 40 nm. In addition, although the material which has green light emission was used in the present Example, it is possible to produce a white organic EL element by laminating | stacking further using blue, red, and a dopant agent.

[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 layer]
Subsequently, on the formed electron injection layer, a mask pattern is formed by using aluminum as a second electrode forming material under a vacuum condition of 5 × 10 ⁻⁴ Pa by a vapor deposition method (vapor phase deposition method) so as to have an extraction electrode. A second electrode layer having a thickness of 100 nm was formed by deposition on the electron injection layer.

  Thus, an organic EL structure was produced.

  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.

(Sealing of sealing material)
Sealing film no. 1. Remove the unnecessary part of the separator film and the sealing material in a vacuum chamber of 10 Pa, expose the adhesive layer, and pattern processing to 50 mm x 50 mm with the organic EL structure formed at 48 mm x 48 mm The adhesive layer of the sealing material was bonded with a lamination roll whose surface was heated to 90 ° C. to form an organic EL element having a sealing width of 2 mm.
The sealing width is the distance from the end of the organic light emitting layer (hole transport layer, light emitting layer, electron injection layer) to the end of the sealing material in the element substrate. Therefore, intrusion is suppressed except for moisture transmitted between the element substrate and the sealing substrate.

  After sealing, after taking out the organic EL sealing structure substrate from the vacuum chamber, it was left in a heating furnace heated to 100 ° C. for 2 hours to thermally cure the adhesive, and the organic EL element no. 4-1.

<Organic EL element no. Preparation of 4-2>
The sealing film is no. 2 as organic EL element no. An organic EL element no. 4-2 was manufactured under the same conditions as in 4-1.

<Organic EL element no. Preparation of 4-3>
The sealing film is no. 3 as organic EL element no. 4-1, the organic EL element no. 4-3 was produced.

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

Evaluation Rank A: Less than 10% probability of occurrence of non-light-emitting portion of 1 mm or more ○ Probability of occurrence of non-light-emitting portion of 1 mm or more 10% or more and less than 20% × Probability of occurrence of non-light-emitting portion of 1 mm or more 20% or more

  Sample of sealing film in which communication hole is formed in first flexible substrate no. 2 and no. Sample of organic EL device using No. 3 4-2 and no. As for 4-3, it was confirmed that favorable sealing performance is obtained.

  Sample of sealing film in which communication holes were not formed in the first flexible substrate no. Sample of organic EL device using No. 1 As for 4-1, the fall of sealing performance was confirmed. 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 light emitting layer 13 2nd electrode 14 Adhesive material layer 15 Sealing base material 16 Element substrate 4 1st flexible base material 5 2nd flexibility Substrate 6 half-cut region 7 full-cut region 8 communication hole 9 opening formed by pattern processing 10 sealing film 20 punching blade 21 ambi roll 22 lami roll 23 unwinding roll 24 winding roll 25 peeling roll 26 bonding roll 26 bonding roll 27 Under vacuum 28 Organic EL structure formation process

Claims (6)

A sealing film comprising a sealing material having a sealing substrate and an adhesive layer between a first flexible substrate and a second flexible substrate,
The sealing material is patterned,
At least one of the first flexible substrate and the second flexible substrate is provided with a communication hole corresponding to an opening formed by patterning a sealing material. the film. A method for producing a sealing film comprising a sealing material having a sealing base material and an adhesive layer between at least a first flexible base material and a second flexible base material,
at least,
A step of patterning the sealing material;
Forming a communication hole corresponding to an opening formed by pattern processing of the sealing material in at least one of the first or second flexible substrate;
The manufacturing method of the sealing film characterized by including.   The method for producing a sealing film according to claim 2, wherein the communication hole is formed simultaneously with patterning of the sealing material. A sealing film in which a first flexible base material, a sealing material having a sealing base material and an adhesive layer, and a second flexible base material are arranged in this order, at least an anode, an organic light emitting layer, and a cathode In the manufacturing method of an organic electroluminescence element formed by bonding to an organic electroluminescence structure having,
A step of patterning the sealing material;
Forming a communication hole corresponding to an opening formed by pattern processing of the sealing material in at least one of the first or second flexible substrate;
Peeling the first flexible substrate from the sealing film;
The manufacturing method of the organic electroluminescent element characterized by having the process of bonding the adhesive material layer surface from which the 1st or 2nd flexible base material was peeled, and the said organic electroluminescent structure.   The organic electroluminescence according to claim 4, wherein the step of bonding the organic electroluminescence structure to the adhesive layer surface from which the first or second flexible base material has been peeled is performed under vacuum. Device manufacturing method.   6. The method of manufacturing an organic electroluminescent element according to claim 4, wherein the communication hole is formed simultaneously with patterning of the sealing material.

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