JP5447244B2 - Method for manufacturing organic electroluminescence panel - Google Patents

Description

The present invention relates to the production how the organic electroluminescence panel using a novel sealing method.

  In recent years, organic electroluminescence (hereinafter also referred to as organic EL) elements have attracted attention as self-luminous elements. An organic EL element has an organic EL structure in which a light emitting layer of an organic compound (hereinafter also referred to as an organic light emitting layer or simply an organic layer) is sandwiched between two electrodes, a negative electrode and a positive electrode, on a substrate such as glass. The device emits light from the organic light emitting layer by supplying a current between the negative electrode and the positive electrode.

  Recently, with the expansion of applications of organic EL elements, organic EL elements using flexible substrates such as resin films have also appeared, and such flexible substrates are used as substrates for organic EL elements. By using it, it has become possible to manufacture an organic EL element by a roll-to-roll method (for example, see Patent Document 1). The roll-to-roll manufacturing method here refers to a substrate wound in a roll shape, which forms an organic EL structure on the substrate, and again winds the substrate on which the organic EL structure is formed on a roll. The manufacturing method of a form is called. The roll-to-roll manufacturing method has the advantage that production efficiency can be improved because continuous production is possible.

  On the other hand, the organic light emitting layer constituting the organic EL element is easily affected by moisture and oxygen, and when left in the air, the quality is deteriorated by moisture and oxygen. Therefore, it is called sealing in the manufacturing process of the organic EL element. A step of forming a protective film for reducing the influence of outside air is added. As a sealing technique of the organic EL element, for example, a thin film such as nitride or nitride oxide is coated on the organic EL structure by an electron beam method, a sputtering method, a plasma CVD method, an ion plating method, or the like. A method for blocking oxygen, specifically, a sealing technique using a facing target type sputtering apparatus (see, for example, Patent Document 2) or a sheet-like sealing substrate is bonded to an organic EL structure and sealed. And a technique for stopping (for example, refer to Patent Document 3).

  A sealing technique for bonding a sealing substrate in a roll-to-roll method is performed by continuously bonding a long sealing substrate to a long substrate on which an organic EL structure is formed. Since the sealing substrate covers the entire organic EL structure, an insulating material is selected for the sealing substrate so as not to cause a short circuit when the organic EL structure is energized.

  By the way, an organic EL element emits light when current is supplied between a positive electrode and a negative electrode sandwiching an organic light emitting layer, and current supply to the positive electrode and the negative electrode is usually an anode and a cathode. Made from each drawer. As described above, in the roll-to-roll production method, alignment is facilitated when the sealing substrate and the substrate have substantially the same width dimension. The organic EL structure formed in the above is continuously covered with a long sealing substrate. That is, the lead portions of the anode and the cathode are also covered with the sealing substrate made of an insulating material. Therefore, in order to supply current to the positive electrode and the negative electrode, it is necessary to remove the sealing substrate which is an insulator covering each lead portion. In response to this problem, an organic EL element of the sealing substrate is bonded to the surface of the long substrate, on which the organic EL structure of the long substrate is formed, with an adhesive layer interposed between the surfaces. A method of manufacturing an organic EL element is disclosed in which an electrode lead portion is cut and removed at a location corresponding to the external lead electrode to form an electrode opening (see, for example, Patent Document 4). However, after the organic EL structure and the sealing substrate are bonded and bonded, the method of forming the opening in the sealing substrate by cutting can certainly set the electrode lead-out part arbitrarily, When cutting and removing the electrode lead-out portion of the sealing substrate, careful attention must be paid so as not to damage the organic light emitting layer, the substrate or the electrode of the organic EL structure substrate.

  In addition, an opening is provided in advance in a position corresponding to the external extraction electrode of the organic EL element on the single-sheet sealing substrate, and then the single-sheet sealing substrate and the organic EL element are bonded together to form an organic material. A method for manufacturing an EL element is disclosed (for example, see Patent Document 5).

  However, the method described in Patent Document 5 is a method in which a single-wafer sheet-shaped sealing substrate and an organic EL element are bonded together in a batch method, and there is a problem that production efficiency is low. Although it is an important condition that the opening is accurately formed at a position corresponding to the electrode position of the organic EL element, no mention or suggestion is made regarding this. In particular, in a method for manufacturing an organic EL element using a roll-to-roll method, the sealing substrate on which an opening is formed in advance as described above is positioned as the electrode portion and the position of the organic EL element corresponding to the opening. It is a very important requirement to manufacture with the same. However, in the roll-to-roll manufacturing process, the organic EL element substrate or the sealing substrate expands and contracts due to changes in environmental conditions and the like, resulting in misalignment in the transport direction or the width direction. There arises a problem that a desired sealing process cannot be performed due to a difference between the electrode positions of the portion and the organic EL element.

International Publication No. 01/005194 Pamphlet JP 2002-332567 A JP 2005-4063 A JP 2007-179783 A JP 2007-194021 A

The present invention has been made in view of the above problems, and its purpose is to form an electrode extraction portion of an organic electroluminescence element substrate with high accuracy and easily at an arbitrary position of a sealing substrate by a roll-to-roll method. it is to provide a manufacturing how the organic electroluminescence panel can be.

  The above object of the present invention is achieved by the following configurations.

1. An organic electroluminescent element substrate in which an organic electroluminescent element having at least a first electrode, an organic functional layer including a light emitting layer, and a second electrode is formed on a long flexible substrate by a roll-to-roll method; In the manufacturing method of an organic electroluminescence panel in which a sealing structure is formed by pasting together a sealing substrate of
After forming the opening for electrode extraction on the flexible sealing substrate according to the electrode position information provided on the organic electroluminescence element substrate, the organic electroluminescence element substrate and the opening for electrode extraction were formed. A manufacturing method of an organic electroluminescence panel, wherein a sealing structure is formed by laminating a sealing substrate.

  2. The organic electroluminescence element substrate has an alignment mark as position information. By detecting the alignment mark, the electrode position of the organic electroluminescence element substrate is specified, and the sealing substrate is attached to the sealing substrate according to the electrode position information. 2. The method for producing an organic electroluminescence panel according to 1 above, wherein an opening for electrode extraction is formed.

  3. 3. The method for producing an organic electroluminescence panel as described in 2 above, wherein the method for detecting the alignment mark is an image recognition method using a CCD camera.

  4). 4. The method for producing an organic electroluminescence panel according to any one of 1 to 3, wherein the method of forming the electrode extraction opening in the sealing substrate is a cutting method using a cutting blade.

  5. 5. The method for producing an organic electroluminescence panel as described in 4 above, wherein the cutting blade is a punch die type in which an upper blade and a lower blade are arranged vertically.

  6). The manufacturing method of the organic electroluminescence panel according to 4 or 5, wherein a transporting speed of the sealing substrate in the cutting step for forming the electrode extraction opening is synchronized with a transporting speed of the organic electroluminescence element substrate. Method.

Provided by the present invention, by a roll-to-roll method, the electrode lead-out portion of the organic electroluminescent device substrate, producing how the organic electroluminescent panel capable of high accuracy and easily formed at an arbitrary position of the sealing substrate We were able to.

It is a process line figure showing an example of a pasting process of an organic EL element substrate and a sealing substrate in a manufacturing method of an organic electroluminescence panel. 2 is a top plan view showing an example of the configuration of an organic electroluminescence element substrate 1 and a sealing substrate 2 used in a method for manufacturing an organic electroluminescence panel. FIG. It is the schematic sectional drawing and schematic top view which show an example of a structure of an organic electroluminescent panel. FIG. 4 is a schematic flow chart until a hole transport layer is formed as a first electrode (anode) constituting the organic EL panel shown in FIG. 3 and an organic functional layer.

  Hereinafter, embodiments for carrying out the present invention will be described in detail.

  As a result of intensive studies in view of the above problems, the inventor has at least a first electrode, an organic functional layer including a light emitting layer, and a second electrode on a long flexible substrate by a roll-to-roll method. In a method for manufacturing an organic electroluminescence panel in which an organic electroluminescence element substrate on which an organic electroluminescence element is formed and a long sealing substrate are bonded to form a sealing structure, the organic electroluminescence panel is formed on the sealing substrate. After forming the electrode extraction opening according to the electrode position information provided on the luminescence element substrate, the organic electroluminescence element substrate and the sealing substrate on which the electrode extraction opening is formed are bonded together to form a sealing structure By a method of manufacturing an organic electroluminescence panel characterized by forming a roll-to-roll system As a result of finding the organic electroluminescence panel manufacturing method capable of easily and accurately forming the electrode extraction portion of the organic electroluminescence element substrate at an arbitrary position of the sealing substrate. is there.

  That is, when forming a sealing structure by associating and bonding a long organic EL element substrate and a sealing substrate that are continuously conveyed by a roll-to-roll method, positional information of electrodes on the organic EL element substrate is obtained. The information is transmitted to the processing part on the sealing substrate side that is to be detected and bonded on time, and an electrode extraction opening is formed in advance at the position where the electrode of the sealing substrate is covered according to the position information of the electrode Then, the organic EL device substrate and the sealing substrate are bonded together, and the method for manufacturing the organic electroluminescence panel in which the electrode extraction portion is formed as an opening portion. According to this method, since the sealing substrate is processed by detecting the electrode position of the organic EL element substrate immediately before bonding, the position of the long organic EL element substrate or the sealing substrate due to expansion / contraction or the like in the transport direction An organic electroluminescence panel in which the electrode extraction opening is formed with extremely high accuracy can be obtained without being affected by the shift. Further, in the method of the present invention, since the electrode position of the organic EL element substrate is detected immediately before processing, the pre-processing of the sealing substrate is not necessary, and even if the electrodes are arranged at various positions, By detecting and feeding back the electrode position information, an electrode extraction opening can be formed at an arbitrary position. Moreover, after forming a sealing structure, it can manufacture without damaging an organic EL element board | substrate compared with the method of removing the sealing substrate located in the electrode part.

  Hereinafter, the detail of the manufacturing method of the organic electroluminescent panel of this invention is demonstrated.

  First, the outline of the manufacturing method of the organic electroluminescence panel of the present invention will be described with reference to the drawings.

  FIG. 1 is a process line diagram illustrating an example of a bonding process between an organic EL element substrate and a sealing substrate in a method for manufacturing an organic electroluminescence panel.

  In FIG. 1, an organic EL element substrate feed roll (unwinder roll) 3 in which an organic EL element substrate 1 is laminated in a roll shape, an organic functional layer including at least a first electrode and a light emitting layer, and a second layer on a flexible substrate. An organic EL element substrate 1 having an organic EL element 2 composed of electrodes and an alignment mark 4 that provides positional information of the electrodes is fed out in the direction of the arrow continuously and at a constant speed. On the other hand, the sealing substrate 5 is transported in the same transport direction as the organic EL element substrate 1 from the sealing substrate feed roll (unwinder roll) 6 in which the sealing substrate 5 is laminated in a roll shape. Feed out in sync with speed.

  The organic EL element substrate 1 fed out from the organic EL element substrate feed roll (unwinder roll) 3 detects the alignment mark 4 given to the organic EL element substrate 1 at the position A by the alignment mark detector 7. Then, the electrode position information of the organic EL element substrate 1 is read. The read electrode position information of the organic EL element substrate 1 is mounted on the transport line of the sealing substrate 5 that is transported in synchronization with the transport speed of the organic EL element substrate 1 via the feedback line 8. Based on the electrode position information sent to the cutting control unit 9, an electrode extraction opening (not shown) is accurately formed at a specified position by using both blades composed of the upper blade 10A and the lower blade 10B. To do.

  Next, an adhesive layer coating liquid composed of, for example, a thermosetting resin or a photocurable resin is applied from the adhesive layer forming unit 12 onto the sealing substrate 5 on which the electrode extraction opening is formed. The adhesive layer 13 is formed by applying to the region excluding the opening for use.

  Next, the organic EL element substrate 1 and the sealing substrate 5 on which the electrode extraction opening is formed and the adhesive layer coating solution is applied are bonded at the bonding portion 14 to a pair of bonding rolls (laminate rolls) 15. At the nip portion formed between them, they are bonded together to form a sealing structure, and then in the curing step 16 of the adhesive layer 13 disposed downstream, heat is applied by the curing means 17 or active energy rays are irradiated. Then, the adhesive layer 13 is cured and finally wound up in a roll shape by the winding roll 18.

  FIG. 2 is a top plan view showing an example of the configuration of the organic electroluminescence element substrate 1 and the sealing substrate 5 used in the method of manufacturing the organic electroluminescence panel shown in FIG.

  2 reads the alignment mark 4 provided on the organic EL element substrate 1 at the position A in FIG. 1, and based on the position information, the electrode is placed at a predetermined position on the sealing substrate 5. The flow for forming the extraction openings 20A and 20B is shown.

  In FIG. 2 a, the arrangement of each component on the organic EL element substrate 1 is shown. On the substrate, an organic EL element 2 composed of an electrode and an organic functional layer is disposed, and the electrodes 19A and 19B are drawn therefrom. Further, alignment marks 4 are provided as corner registration marks at four locations around the organic EL element 2.

The position of the alignment mark 4 is read by an alignment mark detector 7 equipped with a CCD camera or the like as shown in FIG. 1 (process A). From the read information, the positions of the electrodes 19A and 19B arranged on the organic EL element substrate 1 are determined. The read position information of the electrodes 19A, 19B of the organic EL element substrate ₁ is synchronized with the transport speed V1 of the organic EL element substrate 1 via the feedback line 8 shown in FIG. as shown in), the cutting control portion of the sealing substrate 5 is transported at the transportation speed V _2, the electrodes 19A, based on the position information of 19B, respectively corresponding electrode lead-out opening 20A in position, 20B Is formed by cutting with precision using a double-edged blade (process B). In this case, the conveying speed V ₂ of the conveyance speed V ₁ and the sealing substrate 5 of the organic EL device substrate 1, to accurately control the transport speed so that the equivalent. In addition, you may provide the alignment mark 4 also on the sealing substrate 5 as needed.

  FIG. 3 is a schematic cross-sectional view and a schematic top view illustrating an example of the configuration of the organic electroluminescence panel manufactured as described above.

  3A is formed by sealing the organic EL element substrate 1 using the sealing substrate 5 having the electrode extraction openings 20A and 20B (only the electrode extraction opening 20B is shown in the figure). 2 is a schematic cross-sectional view of an organic EL panel 21. FIG.

  An organic EL element substrate in which a first electrode 23, an organic functional layer 24, and a second electrode 25 are formed on a flexible substrate 22 is shown, and a sealing substrate is formed so as to form a sealing structure thereon. 5 is covered, and an electrode extraction opening 20 </ b> B is formed above the first electrode 23 of the sealing substrate 5.

  FIG. 3B is a schematic top view of the organic EL panel 21 having the structure shown in FIG.

  Next, details of each component of the organic EL panel of the present invention will be described.

  The organic EL panel of the present invention includes an organic EL element having at least a first electrode, an organic functional layer including a light emitting layer, and a second electrode on a long flexible substrate. On the flexible substrate, a first electrode (anode), a functional layer composed of a hole transport layer, a light emitting layer and a cathode buffer layer (electron injection layer), and a second electrode (cathode) are sequentially stacked. The organic EL element having the above structure is sealed with a sealing substrate via an adhesive layer.

  Furthermore, the typical layer structure example of the organic electroluminescent panel of this invention is shown below.

(1) Substrate / first electrode (anode) / organic layer (light emitting layer) / second electrode (cathode) / adhesive / sealing substrate (2) substrate / first electrode (anode) / organic layer (light emitting layer) / Electron transport layer / second electrode (cathode) / adhesive / sealing substrate (3) substrate / first electrode (anode) / hole transport layer / organic layer (light emitting layer) / hole blocking layer / electron transport layer / Second electrode (cathode) / adhesive / sealing substrate (4) substrate / first electrode (anode) / hole transport layer (hole injection layer) / organic layer (light emitting layer) / hole blocking layer / electron Transport layer / cathode buffer layer (electron injection layer) / second electrode (cathode) / adhesive / sealing substrate (5) substrate / first electrode (anode) / anode buffer layer (hole injection layer) / hole transport Layer / organic layer (light emitting layer) / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / second electrode (cathode) / adhesive / sealing substrate [organic EL element]
Next, from the flexible substrate constituting the organic EL device according to the present invention and the gas barrier layer formed on the surface thereof, the first electrode, the hole transport layer, the light emitting layer, the cathode buffer layer (electron injection layer) and the like The organic functional layer, the 2nd electrode, etc. which are comprised are demonstrated.

(Flexible substrate)
Examples of the flexible substrate according to the present invention include a strip-shaped flexible substrate. Examples of the flexible substrate include transparent resin films, such as polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, Cellulose acetates such as cellulose acetate propionate (CAP), cellulose acetate phthalate (TAC), cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, Polymethylpentene, polyetherketone, polyimide, polyethersulfone (PES), polyphenylenesulfone , Polysulfones, polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) And the like.

(Gas barrier layer)
A gas barrier layer may be formed on the flexible substrate according to the present invention as necessary. Examples of the gas barrier layer applicable to the present invention include inorganic and organic gas barrier layers or a hybrid gas barrier layer of both. As a material for forming the gas barrier layer, any material may be used as long as it has a function of suppressing intrusion of an element such as moisture or oxygen that causes deterioration of the element. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and layers made of organic materials. Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times. The method for forming the barrier film is not particularly limited, and for example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma polymerization A plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

As a characteristic of the gas barrier layer, the water vapor permeability is preferably 0.01 g / m ² / day or less. Furthermore, a high barrier film having an oxygen permeability of 10 ⁻³ ml / m ² / day / MPa or less and a water vapor permeability of 10 ⁻⁵ g / m ² / day or less is preferable.

(First electrode (anode))
As the first electrode (anode), an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used. Specific examples of such electrode substances include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO. Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ .ZnO) that can form a transparent conductive film may be used. Alternatively, a coatable substance such as an organic conductive compound can be used. In the case where light emission is extracted from the first electrode (anode), it is desirable that the transmittance be greater than 10%, and 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.

(Hole injection layer (anode buffer layer))
A hole injection layer (anode buffer layer) may be present between the first electrode (anode) and the light emitting layer or the hole transport layer. The hole injection layer is a layer provided between the electrode and the organic layer in order to lower the driving voltage and improve the luminance of light emission. “The organic EL element and the forefront of industrialization (November 30, 1998, NTS) The details are described in the second volume, Chapter 2, “Electrode Materials” (pages 123 to 166) of “The Company”. The details of the anode buffer layer (hole injection layer) are described in JP-A Nos. 9-45479, 9-260062, and 8-288069. Specific examples thereof include copper phthalocyanine. Examples thereof include a phthalocyanine buffer layer, an oxide buffer layer typified by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

(Hole transport layer)
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers. The hole transport material has any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

  The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound. Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'- Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and also two of those described in US Pat. No. 5,061,569. Having a condensed aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 are linked in a starburst type ( MTDATA) and the like.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material described in a book (Applied Physics Letters 80 (2002), p. 139) can also be used. In the present invention, it is preferable to use these materials because a light-emitting element with higher efficiency can be obtained.

(Light emitting layer)
The light emitting layer refers to a blue light emitting layer, a green light emitting layer, and a red light emitting layer. There is no restriction | limiting in particular as a lamination order in the case of laminating | stacking a light emitting layer, You may have a nonluminous intermediate | middle layer between each light emitting layer. In the present invention, it is preferable that at least one blue light emitting layer is provided at a position closest to the anode among all the light emitting layers. Also, when four or more light emitting layers are provided, for example, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting from the order close to the anode. Layered / green light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer / green light emitting layer / red light emitting layer, etc. It is preferable for improving luminance stability. A white element can be manufactured by forming a light emitting layer in multiple layers.

  The total thickness of the light emitting layer is not particularly limited, but is usually selected in the range of 2 nm to 5 μm, preferably 2 to 200 nm in consideration of the uniformity of the film and the voltage required for light emission. Furthermore, it is preferable that it exists in the range of 10-20 nm. A film thickness of 20 nm or less is preferable because it has the effect of improving the stability of the emission color with respect to the driving current as well as the voltage surface. The film thickness of each light emitting layer is preferably selected in the range of 2 to 100 nm, and more preferably in the range of 2 to 20 nm. Although there is no restriction | limiting in particular about the film thickness relationship of each light emitting layer of blue, green, and red, It is preferable that the blue light emitting layer (the sum total when there are two or more layers) is the thickest among three light emitting layers.

  The light emitting layer includes at least three layers having different emission spectra, each having an emission maximum wavelength in the range of 430 to 480 nm, 510 to 550 nm, and 600 to 640 nm. If it is three or more layers, there will be no restriction | limiting in particular. When there are more than four layers, there may be a plurality of layers having the same emission spectrum. A layer having an emission maximum wavelength in the range of 430 to 480 nm is referred to as a blue light emitting layer, a layer in the range of 510 to 550 nm is referred to as a green light emitting layer, and a layer in the range of 600 to 640 nm is referred to as a red light emitting layer. Moreover, in the range which maintains the said maximum wavelength, you may mix a several luminescent compound in each light emitting layer. For example, the blue light emitting layer may be used by mixing a blue light emitting compound having a maximum wavelength of 430 to 480 nm and a green light emitting compound having the same wavelength of 510 to 550 nm.

  The organic light emitting material used as the material of the light emitting layer is (a) charge injection function, that is, holes can be injected from the anode or hole injection layer when an electric field is applied, and electrons are injected from the cathode or electron injection layer. (B) a transport function, that is, a function that moves injected holes and electrons by the force of an electric field, and (c) a light emission function, that is, a recombination field of electrons and holes. However, there is no particular limitation as long as it has the three functions of connecting these to light emission. For example, fluorescent whitening agents such as benzothiazole, benzimidazole, and benzoxazole, and styrylbenzene compounds can be used. Specific examples of the above-mentioned optical brightener include 2,5-bis (5,7-di-t-pentyl-2-benzoxazolyl) -1,3,4-thiadiazole in the benzoxazole series, 4 , 4'-bis (5,7-t-pentyl-2-benzoxazolyl) stilbene, 4,4'-bis [5,7-di- (2-methyl-2-butyl) -2-benzoxa Zoolyl] stilbene, 2,5-bis (5,7-di-t-pentyl-2-benzoxazolyl) thiophene, 2,5-bis [5-α, α-dimethylbenzyl-2-benzoxazoli Ru] thiophene, 2,5-bis [5,7-di- (2-methyl-2-butyl) -2-benzoxazolyl] -3,4-diphenylthiophene, 2,5-bis (5-methyl) -2-benzoxazolyl) thiophene, 4,4'-bis (2 -Benzoxazolyl) biphenyl, 5-methyl-2- [2- [4- (5-methyl-2-benzoxazolyl) phenyl] vinyl] benzoxazole, 2- [2- (4-chlorophenyl) vinyl Naphtho [1,2-d] oxazole and the like. Examples of the benzothiazole type include 2,2 '-(p-phenylenedivinylene) -bisbenzothiazole, and examples of the benzimidazole type include 2- [2- [4- (2-benzimidazolyl) phenyl] vinyl] benzimidazole. 2- [2- (4-carboxyphenyl) vinyl] benzimidazole and the like. In addition, other useful compounds are listed in Chemistry of Synthetic Soybean (1971), pages 628-637 and 640. Specific examples of the styrylbenzene compound include 1,4-bis (2-methylstyryl) benzene, 1,4-bis (3-methylstyryl) benzene, 1,4-bis (4-methylstyryl). ) Benzene, distyrylbenzene, 1,4-bis (2-ethylstyryl) benzene, 1,4-bis (3-methylstyryl) benzene, 1,4-bis (2-methylstyryl) -2-methylbenzene, 1,4-bis (2-methylstyryl) -2-ethylbenzene and the like can be mentioned.

  Further, in addition to the above-described optical brightener and styrylbenzene compound, for example, 12-phthaloperinone, 1,4-diphenyl-1,3-butadiene, 1,1,4,4-tetraphenyl-1,3- Butadiene, naphthalimide derivatives, perylene derivatives, oxadiazole derivatives, aldazine derivatives, pyrazirine derivatives, cyclopentadiene derivatives, pyrrolopyrrole derivatives, styrylamine derivatives, coumarin compounds, international publications WO 90/13148 and Appl. Phys. Lett. , Vol 58, 18, P1982 (1991), and aromatic dimethylidin compounds. Specific examples of the aromatic dimethylidin compounds include 1,4-phenylene dimethylidin, 4,4'-phenylene dimethylidin, 2,5-xylylene dimethylidin, 2,6-naphthylene dimethylidin, 1,4-biphenylenedimethylidin, 1,4-p-terephenylenedimethylidin, 4,4'-bis (2,2-di-t-butylphenylvinyl) biphenyl, 4,4'-bis (2 , 2-diphenylvinyl) biphenyl and the like, and derivatives thereof. Specific examples of the compound represented by the general formula (I) include bis (2-methyl-8-quinolinolato) (p-phenylphenolate) aluminum (III), bis (2-methyl-8-quinolinolato). ) (1-naphtholate) aluminum (III) and the like.

  In addition, a compound in which the above-described organic light-emitting material is used as a host and the host is doped with a strong fluorescent dye from blue to green, for example, coumarin-based or the same fluorescent dye as the host, is also suitable as the organic light-emitting material. When the above-described compound is used as the organic light-emitting material, blue to green light emission (the emission color varies depending on the type of dopant) can be obtained with high efficiency. Specific examples of the host that is the material of the compound include organic light-emitting materials having a distyrylarylene skeleton (particularly preferably, for example, 4,4′-bis (2,2-diphenylvinyl) biphenyl). Specific examples of the dopant which is a material of diphenylaminovinylarylene (particularly preferably, for example, N, N-diphenylaminobiphenylbenzene and 4,4′-bis [2- [4- (N, N-di- -P-tolyl) phenyl] vinyl] biphenyl).

  The light emitting layer preferably contains a known host compound and a known phosphorescent compound (also referred to as a phosphorescent compound) in order to increase the light emission efficiency of the light emitting layer.

  The host compound is a compound contained in the light-emitting layer, the mass ratio in the layer is 20% or more, and the phosphorescence quantum yield of phosphorescence emission is 0.1 at room temperature (25 ° C.). Is defined as less than a compound. The phosphorescence quantum yield is preferably less than 0.01. A plurality of host compounds may be used in combination. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. In addition, by using a plurality of phosphorescent compounds, it is possible to mix different light emission, thereby obtaining an arbitrary emission color. White light emission is possible by adjusting the kind of phosphorescent compound and the amount of doping, and can also be applied to illumination and backlight.

  As these host compounds, compounds having a hole transporting ability and an electron transporting ability, preventing emission light from being increased in wavelength, and having a high Tg (glass transition temperature) are preferable. Known host compounds include, for example, JP-A Nos. 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, and 2002-334786. Gazette, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645 2002-338579, 2002-105445, 2002-343568, 2002-141173, 2002-352957, 2002-203683, 2002-363227 2002-231453, 2003-3165, 2002-234888, 2003-27048, 2002-255934, 2002-260861, 2002-280183, Examples thereof include compounds described in 2002-299060, 2002-302516, 2002-305083, 2002-305084, 2002-308837 and the like.

  In the case of having a plurality of light emitting layers, it is preferable that 50% by mass or more of the host compound in each layer is the same compound because it is easy to obtain a uniform film property over the entire organic layer. It is more preferable that the light emission energy is 2.9 eV or more because it is advantageous in efficiently suppressing energy transfer from the dopant and obtaining high luminance. Phosphorescence emission energy means the peak energy of the 0-0 band of phosphorescence emission when the photoluminescence of a deposited film of 100 nm is measured on a substrate with a host compound.

  The host compound has a phosphorescence emission energy of 2.9 eV or more and a Tg of 90 ° C. or more in consideration of deterioration of the organic EL device over time (decrease in luminance and film properties), market needs as a light source, and the like. Preferably there is. That is, in order to satisfy both luminance and durability, it is preferable that phosphorescence emission energy is 2.9 eV or more and Tg is 90 ° C. or more. Tg is more preferably 100 ° C. or higher.

  A phosphorescent compound (phosphorescent compound) is a compound in which light emission from an excited triplet is observed, is a compound that emits phosphorescence at room temperature (25 ° C.), and has a phosphorescence quantum yield of 25. The compound is 0.01 or more at ° C. When used in combination with the host compound described above, an organic EL device with higher luminous efficiency can be obtained.

  The phosphorescent compound according to the present invention preferably has a phosphorescence quantum yield of 0.1 or more. The phosphorescent quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 version, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence quantum yield used in the present invention only needs to achieve the phosphorescence quantum yield in any solvent.

  There are two types of light emission of the phosphorescent compound in principle. One is the recombination of the carrier on the host compound to which the carrier is transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent compound. The energy transfer type is to obtain light emission from the phosphorescent compound by moving to the other, and the other is that the phosphorescent compound becomes a carrier trap, and carrier recombination occurs on the phosphorescent compound, and the phosphorescent compound emits light. Although it is a carrier trap type in which light emission can be obtained, in any case, it is a condition that the excited state energy of the phosphorescent compound is lower than the excited state energy of the host compound.

  The phosphorescent compound can be appropriately selected from known compounds used for the light emitting layer of the organic EL device. The phosphorescent compound is preferably a complex compound containing a group 8-10 metal in the periodic table of elements, more preferably an iridium compound, an osmium compound, or a platinum compound (platinum complex compound), rare earth Of these, iridium compounds are the most preferred.

  In the present invention, the phosphorescence emission maximum wavelength of the phosphorescent compound is not particularly limited, and can be obtained in principle by selecting a central metal, a ligand, a ligand substituent, and the like. The emission wavelength can be changed.

  The light emission color of the organic EL device of the present invention and the compound according to the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). It is determined by the color when the result measured with the total CS-1000 (manufactured by Konica Minolta Sensing) is applied to the CIE chromaticity coordinates.

The white element referred to in the present invention means that the chromaticity in the CIE1931 color system at 1000 cd / m ² is X = 0.33 ± 0.07 when the front luminance at 2 ° viewing angle is measured by the above method. It is in the region of Y = 0.33 ± 0.07.

(Electron injection layer)
The electron injection layer is made of a material having a function of transporting electrons and is included in the electron transport layer in a broad sense. The electron injection layer is a layer provided between the electrode and the organic layer for lowering the driving voltage and improving the luminance of the light emission. “Organic EL element and its forefront of industrialization (NST 30, November 30, 1998) Issue) ”, Chapter 2, Chapter 2,“ Electrode Materials ”(pages 123-166). Details of the electron injection layer (cathode buffer layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. A metal buffer layer typified by lithium fluoride, an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, an oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and the film thickness is preferably in the range of 0.1 nm to 5 μm although it depends on the material.

  In addition, as an electron transport material (also serving as a hole blocking material) used for the electron transport layer adjacent to the light emitting layer side, it is sufficient if it has a function of transmitting electrons injected from the cathode to the light emitting layer. As a material, any one of conventionally known compounds can be selected and used. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodisides. Examples include methane and anthrone derivatives, oxadiazole derivatives and the like. Furthermore, in the above oxadiazole derivatives, thiadiazole derivatives in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and quinoxaline derivatives having a quinoxaline ring known as an electron-withdrawing group can also be used as the electron transport material. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  Also, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum. Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), and the like, and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga or Pb can also be used as the electron transport material. In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. Distyrylpyrazine derivatives can also be used as electron transport materials, and inorganic semiconductors such as n-type-Si and n-type-SiC are also used as electron transport materials in the same manner as the hole injection layer and hole transport layer. I can do it. Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  An electron transport layer having a high n property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, JP-A-2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like. It is preferable to use such an electron transport layer having a high n property because an element with lower power consumption can be manufactured.

  The external extraction efficiency at room temperature of light emission of the organic EL device according to the present invention is preferably 1% or more, more preferably 5% or more. Here, the external extraction quantum efficiency (%) = the number of photons emitted to the outside of the organic EL element / the number of electrons sent to the organic EL element × 100.

  In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor may be used in combination. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

(Electron injection layer (cathode buffer layer))
The electron injection layer (cathode buffer layer) formed in the electron injection layer forming step is made of a material having a function of transporting electrons and is included in the electron transport layer in a broad sense. The electron injection layer is a layer provided between the electrode and the organic layer for lowering the driving voltage and improving the luminance of the light emission. “Organic EL element and its forefront of industrialization (NST 30, November 30, 1998) Issue) ”, Chapter 2, Chapter 2,“ Electrode Materials ”(pages 123-166). Details of the electron injection layer (cathode buffer layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. A metal buffer layer typified by lithium fluoride, an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, an oxide buffer layer typified by aluminum oxide, etc. .

(Second electrode (cathode))
As the second electrode (cathode), a material having a small work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like. Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering.

  In order to transmit the emitted light, if either one of the first electrode (anode) or the second electrode (cathode) of the organic EL element is transparent or translucent, the emission luminance is advantageously improved.

  Moreover, after producing the metal with a thickness of 1 to 20 nm on the second electrode, the conductive transparent material mentioned in the description of the first electrode is produced thereon, so that a transparent or translucent second electrode ( A cathode) can be manufactured, and by applying this, an element in which both the first electrode (anode) and the second electrode (cathode) are transmissive can be manufactured.

[Sealing substrate]
Next, the configuration of the sealing substrate will be described.

  The substrate applied to the sealing substrate according to the present invention is a flexible substrate, for example, ethylene tetrafluoroethyl copolymer (ETFE), high density polyethylene (HDPE), expanded polypropylene (OPP), polystyrene (PS). Thermoplastic resin film materials used for general packaging films such as polymethyl methacrylate (PMMA), stretched nylon (ONy), polyethylene terephthalate (PET), polycarbonate (PC), polyimide, polyether styrene (PES) Can be mentioned. As these thermoplastic resin films, a multilayer film made by coextrusion with a different film, a multilayer film made by laminating at different stretching angles, and the like can be used as needed. Further, it is naturally possible to combine the density and molecular weight distribution of the film used to obtain the required physical properties.

  In the case of a thermoplastic resin film, it is necessary to form a gas barrier layer by vapor deposition or coating. Examples of the gas barrier layer include a metal vapor deposition film and a metal foil. As inorganic vapor deposition films, thin film handbooks p879-p901 (Japan Society for the Promotion of Science), vacuum technology handbooks p502-p509, p612, p810 (Nikkan Kogyo Shimbun), vacuum handbook revised editions p132-p134 (ULVAC Japan Vacuum Technology KK) The metal vapor deposition film as described in the above. For example, metals such as In, Sn, Pb, Au, Cu, Ag, Al, Ti, and Ni are used. As the material of the metal foil, for example, a metal material such as aluminum, copper, or nickel, or an alloy material such as stainless steel or an aluminum alloy can be used. Aluminum is preferable in terms of workability and cost. The film thickness is about 1 to 100 μm, preferably about 10 to 50 μm. In order to facilitate handling during production, a film such as polyethylene terephthalate or nylon may be laminated in advance. When using a resin film for a flexible sealing substrate, it is preferable to have a thermoplastic adhesive resin layer on the side in contact with the liquid sealing agent.

  Furthermore, a protective layer may be provided on the gas barrier layer. The thickness of the protective layer is preferably 100 nm to 200 μm in consideration of stress cracking resistance, electrical insulation resistance of the gas barrier layer, adhesiveness (adhesive force, step following ability) and the like when used as a sealant layer. As the protective layer, a thermoplastic resin film having a JIS K 7210 standard melt flow rate of 5 to 20 g / 10 min is preferable, and a thermoplastic resin film of 6 to 15 g / 10 min or less is more preferably used. This is because if a resin having a melt flow rate of 5 g / 10 min or less is used, the gap caused by the step of the extraction electrode of each electrode cannot be completely filled, and if a resin having a melt flow rate of 20 g / 10 min or more is used, the tensile strength and This is because stress cracking properties, workability, and the like are reduced.

The water vapor permeability of the flexible sealing substrate according to the present invention is preferably 0.01 g / m ² · day or less in consideration of a gas barrier property required for commercialization as an organic EL panel. The oxygen permeability is preferably 0.1 ml / m ² · day · MPa or less. The moisture permeability is a value measured mainly by the MOCON method by a method based on the JIS K7129B method (1992), and the oxygen permeability is a value measured mainly by the MOCON method by a method based on the JIS K7126B method (1987). is there. The Young's modulus of the flexible sealing substrate is 1 × 10 ⁻³ GPa to 80 GPa and the thickness is 10 μm to 500 μm in consideration of adhesion to the organic EL element, prevention of spreading of the liquid adhesive, and the like. preferable.

〔adhesive〕
In the method for producing an organic electroluminescence panel of the present invention, an organic electroluminescence panel is produced by laminating an organic EL element substrate and a sealing substrate with an adhesive.

  Examples of the adhesive used in the production of the organic electroluminescence panel of the present invention include a photocurable or thermosetting liquid adhesive, a thermoplastic resin, a photocurable resin, and the like. Examples of the liquid adhesive include photo-curing and thermosetting sealing agents having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, moisture-curing adhesives such as 2-cyanoacrylate, epoxy-based adhesives, etc. And heat curing and chemical curing type (two-component mixing) adhesives, cationic curing type ultraviolet curing epoxy resin adhesives, and the like. It is preferable to add a filler to the liquid adhesive as necessary. The addition amount of the filler is preferably 5 to 70% by volume in consideration of adhesive strength. In addition, the size of the filler to be added is preferably 1 μm to 100 μm in consideration of the adhesive strength, the adhesive thickness after pasting and pressure bonding, and the like. 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.

When the sealing substrate and the organic EL element are bonded using a liquid adhesive, the bonding part has bonding stability, prevention of air bubbles mixing into the bonding part, flatness of the flexible sealing substrate, etc. Is preferably performed under reduced pressure conditions of 10 to 1 × 10 ⁻⁵ Pa.

  As the thermoplastic resin, a thermoplastic resin having a melt flow rate of JIS K 7210 specified in a range of 5 to 20 g / 10 min is preferable, and a thermoplastic resin of 6 to 15 g / 10 min or less is more preferably used. This is because if a resin with a melt flow rate of 5 (g / 10 min) or less is used, the gap formed by the steps of the extraction electrode of each electrode cannot be completely filled, and a resin of 20 (g / 10 min) or more cannot be filled. This is because if used, the tensile strength, stress cracking resistance, workability and the like are lowered. The laminating method can be made by using various generally known methods such as a wet laminating method, a dry laminating method, a hot melt laminating method, an extrusion laminating method, and a thermal laminating method.

  The thermoplastic resin is not particularly limited as long as it satisfies the above numerical values. For example, low density polyethylene (LDPE) which is a polymer film described in the new development of functional packaging materials (Toray Research Center, Inc.). ), HDPE, linear low density polyethylene (LLDPE), medium density polyethylene, unstretched polypropylene (CPP), OPP, ONy, PET, cellophane, polyvinyl alcohol (PVA), stretched vinylon (OV), ethylene-vinyl acetate copolymer A combination (EVOH), ethylene-propylene copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, vinylidene chloride (PVDC), or the like can be used. Among these thermoplastic resins, LDPE, LLDPE produced using LDPE, LLDPE and a metallocene catalyst, or a thermoplastic resin using a mixture of LDPE, LLDPE and HDPE films is preferably used.

[Other components]
The organic EL device according to the present invention is preferably used in combination with the following method in order to efficiently extract light generated in the light emitting layer. The organic EL element emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1), and only about 15% to 20% of the light generated in the light emitting layer can be extracted. It is generally said that there is no. This is because the light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the element, or the transparent electrode or light emitting layer and the transparent substrate This is because the light undergoes total reflection between them, the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the side surface of the device.

  As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the interface between the transparent substrate and the air (US Pat. No. 4,774,435). A method for improving efficiency by providing a substrate with a light condensing property (JP-A-63-314795). A method of forming a reflective surface on the side surface of an element (Japanese Patent Laid-Open No. 1-220394). A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between a substrate and a light emitter (Japanese Patent Laid-Open No. 62-172691). A method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter (Japanese Patent Laid-Open No. 2001-202827). There is a method of forming a diffraction grating between any one of the substrate, the transparent electrode layer, and the light emitting layer (including between the substrate and the outside) (Japanese Patent Laid-Open No. 11-283951).

  In the present invention, these methods can be used in combination with an organic EL element. However, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or a substrate, a transparent electrode layer, A method of forming a diffraction grating between any layers of the light emitting layer (including between the substrate and the outside) can be suitably used. In the present invention, by combining these means, it is possible to obtain an element having higher luminance or durability.

  When a low refractive index medium is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower. . Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less. Further, it is preferably 1.35 or less. The thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate. The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency. This method is generated from the light emitting layer by utilizing the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction such as first-order diffraction and second-order diffraction. Of the light, the light that cannot go out due to total reflection between layers, etc. is diffracted by introducing a diffraction grating into any layer or medium (inside a transparent substrate or transparent electrode) , Trying to extract light out. It is desirable that the diffraction grating to be introduced has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. The light extraction efficiency does not increase so much. However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and the light extraction efficiency is increased.

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated. At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium. The arrangement of the diffraction grating is preferably two-dimensionally repeated, such as a square lattice, a triangular lattice, or a honeycomb lattice.

  Furthermore, the organic EL element according to the present invention is processed so as to provide, for example, a structure on a microlens array on the light extraction side of the substrate in order to efficiently extract light generated in the light emitting layer, or a so-called condensing sheet. By combining with, the luminance in the specific direction can be increased by condensing light in a specific direction, for example, the front direction with respect to the element light emitting surface. As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 μm to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  As the condensing sheet, for example, a sheet that is put into practical use in an LED backlight of a liquid crystal display device can be used. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, the substrate may be formed with a triangle stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded, and the pitch is randomly changed. The shape may be other shapes. Moreover, in order to control the light emission angle from a light emitting element, you may use a light-diffusion plate and a film together with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

<< Method for Manufacturing Organic Electroluminescence Panel >>
In the method for producing an organic electroluminescence panel of the present invention, an opening for electrode extraction is formed on a flexible sealing substrate according to electrode position information provided on the organic electroluminescence element substrate, and then the organic electroluminescence element is formed. A sealing structure is formed by bonding a substrate and a sealing substrate on which the electrode extraction opening is formed.

[Manufacture of organic electroluminescence element substrate]
In FIG. 4, an example of the manufacturing method of the organic electroluminescent element substrate which concerns on this invention is shown.

  FIG. 4 is a schematic flow chart until the hole transport layer is formed as the first electrode (anode) constituting the organic EL panel shown in FIG. 3 and the organic functional layer.

  Hereinafter, according to the flow of Step 1 to Step 3, the steps from application of alignment marks to formation of the first electrode (anode) and the hole transport layer on the strip-shaped flexible substrate will be described.

  In Step 1, a strip-shaped flexible substrate 22 is prepared. Reference numeral 4 denotes an alignment mark for determining a position where the first electrode (anode) 23 is formed.

  The alignment mark 4 determines the installation position of the first electrode (anode) or the second electrode (cathode) to be formed thereafter (particularly, the positions of the extraction electrode portions 23a and 25a of the respective electrodes). In the same manner as the first electrode forming method, the alignment mark 4 is applied by forming a film on a predetermined position of the substrate 22 by sputtering using the material of the first electrode (anode), for example, ITO. Can do.

  In Step 2, the position at which the first electrode (anode) 23 is formed is determined according to the alignment mark 4 applied to the flexible substrate 22, and the first electrode (anode) having the extraction electrode portion 23a is determined by a mask pattern film forming method. 23 is formed. The mask pattern film forming method is, for example, using a mask having a required shape when ITO is formed on the flexible substrate 22 by sputtering as a material for the first electrode (anode) 23. Say how to do.

  In Step 3, a hole transport layer 27, which is an organic compound, is laminated on the entire surface of the first electrode (anode) 22 except for a portion that becomes the extraction electrode 22 a according to the alignment mark 4 attached to the flexible substrate 22.

  Step 1 to Step 3 are preferably performed continuously in a vacuum environment. “Consecutively performing” means that each step of Step 1 to Step 3 is placed in a vacuum environment when moving to the next Step. After Step 3, the step of forming the light emitting layer may not be in a vacuum environment. By performing Step 1 to Step 3 continuously in a vacuum environment, it is possible to prevent foreign matter from adhering to the first electrode (anode) 102.

  Next, on the hole transport layer 27 formed above, an organic functional layer 24 composed of a light emitting layer, an electron transport layer, and an electron injection layer, and a second electrode (cathode) 25 are formed to produce an organic EL device. The

  In the light emitting layer forming step, the light emitting layer forming coating solution is applied on the hole transport layer excluding the extraction electrode portion of the flexible substrate 22 on which the hole transport layer 27 is formed, and the light emitting layer is formed through the drying section. It is formed.

  The coating solution for forming the light emitting layer used for forming the light emitting layer is already formed except that the alignment mark attached to the flexible substrate 22 is detected by the alignment mark detector and the first electrode (anode) is removed. Applied to the hole transport layer.

  Usable wet coaters include, for example, die coating method, screen printing method, flexographic printing method, ink jet method, wire bar method, cap coating method, spray coating method, casting method, roll coating method, bar coating method, gravure coating. It is possible to use a coating machine such as a method. The use of these wet coating machines can be appropriately selected according to the material of the light emitting layer. When the organic EL panel is a full color system, the light emitting layer is pattern-coated on the first electrode (anode) in accordance with the pattern of the first electrode (anode) formed by patterning. Various coating apparatuses used for a flexographic printing method, an offset printing method, a gravure printing method, a screen printing method, a spray coating method using a mask, and the like can be used.

  In addition, when the light emitting layer is a multilayer, it is necessary to dispose units for the coating / drying unit in accordance with the number of layers to be stacked. For example, a white element can be manufactured by forming a light emitting layer in multiple layers. The light emitting layer refers to a blue light emitting layer, a green light emitting layer, and a red light emitting layer. There is no restriction | limiting in particular as a lamination order in the case of laminating | stacking a light emitting layer, You may have a nonluminous intermediate | middle layer between each light emitting layer. In the present invention, it is preferable that at least one blue light emitting layer is provided at a position closest to the anode among all the light emitting layers. Also, when four or more light emitting layers are provided, for example, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting from the order close to the anode. Layered / green light emitting layer, blue light emitting layer / green light emitting layer / red light emitting layer / blue light emitting layer / green light emitting layer / red light emitting layer, etc. It is preferable for improving luminance stability.

  The total thickness of the light emitting layer is not particularly limited, but is usually selected in the range of 2 nm to 5 μm, preferably 2 nm to 200 nm in consideration of the film homogeneity, the voltage required for light emission, and the like. Further, it is preferably in the range of 10 nm to 20 nm. A film thickness of 20 nm or less is preferable because it has the effect of improving the stability of the emission color with respect to the driving current as well as the voltage surface. The film thickness of each light emitting layer is preferably selected in the range of 2 nm to 100 nm, and more preferably in the range of 2 nm to 20 nm. Although there is no restriction | limiting in particular about the film thickness relationship of each light emitting layer of blue, green, and red, It is preferable that the blue light emitting layer (the sum total when there are two or more layers) is the thickest among three light emitting layers.

  In the winding unit, the flexible substrate 22 having the light emitting layer formed by the winding device is wound into a roll and stored. Thereafter, it is sent to the electron injection layer forming step.

  In the electron injection layer forming step, the alignment mark attached to the flexible substrate 22 continuously supplied from the feeding portion is read by the detection device and taken out to the position determined by the vapor deposition device 205b according to the information of the detection device. Except for the electrodes, an electron injection layer is formed as a mask pattern on the already formed light emitting layer. The thickness of the electron injection layer is preferably in the range of 0.1 nm to 5 μm.

  In the second electrode formation step 206, the alignment mark attached to the flexible substrate 22 continuously supplied from the electron injection layer formation step is read by the detection device, and determined by the vapor deposition device according to the information of the detection device. A second electrode (cathode) having an extraction electrode is formed in a mask pattern on the already formed electron injection layer. The sheet resistance as the second electrode (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, an organic EL device having a configuration of substrate / first electrode (anode) / hole transport layer / light emitting layer / electron injection layer / second electrode (cathode) is produced.

  In the above description of the second electrode (cathode) forming step and the cathode buffer layer (electron injection layer) forming step, the case of the vapor deposition apparatus has been shown. However, the method for forming the second electrode (cathode) and the cathode buffer layer (electron injection layer) 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 CVD method Further, a thermal CVD method, a coating method, or the like can be used.

[Detection of alignment mark on organic electroluminescence element substrate]
The alignment mark 4 applied to the organic electroluminescence element substrate 1 according to the above method is the electrode in the organic EL element 2 from the position where the alignment mark 4 is applied by the alignment mark detection unit 7 at the position A shown in FIG. Identify the location.

  As a method for reading the alignment mark 4, the reading is performed by a CCD camera installed in the alignment mark detection unit 7, and the read information is processed.

[Formation of electrode extraction opening on sealing substrate]
After the alignment mark detection unit 7 specifies the position of the alignment mark 4 on the organic electroluminescence element substrate 1 and the position of the extraction electrode obtained thereby, the electrode position information is transmitted via the information position feedback line 8. The electrode extraction opening is cut to a predetermined position of the sealing substrate 4 using a cutting blade based on the information transmitted to the cutting control unit 9 provided in the conveyance line of the sealing substrate 5. Form. There is no limitation in particular as a cutting blade, For example, a hollow blade system, a punch die system, etc. can be used. The hollow blade method is a blade that is punched with a blade from above, and has a blade edge angle of about 30 ° when punched. The punch die method uses a die having a pair of upper and lower blades, and the angle of the upper and lower blades is around 90 °. The punch die method is preferable because of the durability of the blade.

  At this time, it is possible to use the method of performing the oscillating cut by synchronizing the transport speed V <b> 2 of the sealing substrate 4 that forms the electrode extraction opening and the transport speed V <b> 1 of the organic electroluminescence element substrate 1. On the other hand, the electrode extraction opening can be formed at a position corresponding to the extraction electrode of the organic electroluminescence element substrate 1 with high accuracy.

  Examples of the cutting method for forming the electrode extraction opening using the cutting blade are described in, for example, Japanese Patent Application Laid-Open Nos. 2003-251587, 2004-58180, and 2006-181669. The method that can be applied.

(Formation of adhesive layer)
The forming step of the adhesive layer is a step of forming the adhesive layer by applying the adhesive by a screen printing method to a region other than the area where the opening for extracting the electrode of the sealing substrate is formed.

  The screen printing method is a method in which an adhesive layer coating solution is spread on a plate (stencil) with a squeegee (scalar) and rubbed, and the adhesive is applied to the sealing substrate through the screen mesh stretched on the opening of the sealing substrate. This is a printing method in which an adhesive layer is formed by adhering a layer coating liquid, and the adhesive layer coating liquid is applied only to a position range facing a plate opening (a region other than where the electrode extraction opening is formed). Can be selectively deposited.

  Examples of the adhesive that can be used for forming the adhesive layer in the present invention include the above-mentioned photo-curing or thermosetting liquid adhesives, thermoplastic resins, and photo-curing resins.

  In the adhesive layer forming step, a squeegee is provided, and the squeegee spreads and rubs the adhesive on the stencil at the tip. The stencil has an opening with a screen that allows the adhesive to pass through the opening, and a mask that cannot pass through the adhesive, and the adhesive spread and rubbed on the stencil by the squeegee It is applied to a region that passes through the screen of the opening and faces the opening of the sealing substrate. On the other hand, since the adhesive cannot pass through the mask portion, the adhesive is not applied to the region facing the mask portion.

[Bonding process]
The bonding step 14 shown in FIG. 1 is performed by pressure bonding the organic EL element substrate 1 being conveyed at the same speed and the sealing substrate 5 provided with the adhesive layer 13 with a bonding roll 15. In this step, the sealing substrate 5 is attached to the substrate 1 via the adhesive layer 13. That is, the bonding process 14 has the bonding roll 15 up and down, and the sealing substrate 5 is laminated to the organic EL element substrate 1 through the adhesive layer 13 by pressurization of the upper and lower bonding roll 15.

[Curing process of adhesive layer]
After bonding the sealing substrate 5 and the organic EL element substrate 1 in the bonding step 14, the adhesive layer 13 is cured in the curing step 16.

  When the material constituting the adhesive layer is a photocurable resin, examples of the curing means 17 include an active energy ray light source that is an ultraviolet ray or an electron beam, such as an ultraviolet ray or an electron beam. Examples include ultraviolet LEDs, ultraviolet rays, lasers, mercury arc lamps, xenon arc lamps, low pressure mercury lamps, fluorescent lamps, carbon arc lamps, tungsten-halogen copying lamps, and sunlight.

  Moreover, when the material which comprises the adhesive bond layer is a thermosetting resin, as the hardening means 17, it can be hardened by heating to desired temperature using a heat provision means, A heating means Examples thereof include a heating fan, a surface heater, a heating roller, a heating belt, radiant heat heating such as a halogen heater and a far infrared heater.

  Hereinafter, although an example is given and the concrete effect of the present invention is shown, the mode of the present invention is not limited to this.

Example 1
<< Preparation of organic EL panel 1 >>
Using the manufacturing process shown in FIG. 1, an organic EL in which a first electrode, a hole transport layer, a light-emitting layer, an electron transport layer, and a second electrode are formed in this order on a flexible substrate by the following method. An organic EL panel 1 in which the element substrate was sealed with a sealing substrate was produced.

[Preparation of organic EL element substrate 1]
(Preparation of flexible substrate)
As a flexible substrate, a polyethylene terephthalate film having a thickness of 100 μm (a film made by Teijin and DuPont, hereinafter abbreviated as PET) is prepared. Using an atmospheric pressure plasma discharge treatment apparatus having a structure described in Kai 2004-68143, an inorganic gas barrier film made of SiO _x is continuously formed on a flexible film so as to have a thickness of 500 nm. 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 g / m ² / day or less was produced.

(Applying alignment marks)
On the flexible substrate, an alignment mark for indicating the formation position of the first electrode was applied as a corner registration mark as described in Step 1 of FIG.

The alignment marks were formed by forming sputtering marks with a 120 nm thick ITO (indium tin oxide) film at the four corners of the flexible substrate under a vacuum environment condition of 5 × 10 ⁻¹ Pa by a sputtering method.

(Formation of first electrode and hole transport layer)
Next, according to Steps 1 to 3 in FIG. 4, a first electrode (anode) and a hole transport layer were continuously formed on a long flexible substrate provided with an alignment mark according to the following.

<Formation of the first electrode>
A mask pattern is formed as shown in Step 2 of FIG. 4 by sputtering ITO (indium tin oxide) having a thickness of 120 nm on a flexible substrate under a vacuum environment condition of 5 × 10 ⁻¹ Pa to obtain an effective pixel region. A first electrode having a size having extraction electrodes of 80 mm × 50 mm and 40 mm × 20 mm was continuously formed at regular intervals.

<Formation of hole transport layer>
Except for the portion that becomes the extraction electrode 23a on the first electrode 23 formed as shown in Step 3 of FIG. 4, N, N′-diphenyl is used as a hole transport layer forming material under a vacuum environment condition of 5 × 10 ⁻⁴ Pa. -N, N'-m-tolyl 4,4'-diamino-1,1'-biphenyl was laminated by vapor deposition (vapor phase deposition) to form a 30 nm thick hole transport layer.

  Next, 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 element substrate 1 and wound into a roll.

(Formation of light emitting layer)
The following light emitting layer forming coating solution was applied by a wet coating method using an extrusion coating machine so that the thickness after drying was 100 nm. After forming the light emitting layer, antistatic treatment was performed, and the mixture was cooled to the same temperature as room temperature, and then wound around the winding core. The conveyance speed was 2 m / min.

<Preparation of light emitting layer forming coating solution>
5% by mass of the dopant material Ir (ppy) ₃ was dissolved in 1,2-dichloroethane in polyvinylcarbazole (PVK) as a host material to prepare a 10% solution as a light emitting layer forming coating solution. The surface tension of the coating solution for forming the light emitting layer was 32 × 10 ⁻³ N / m (manufactured by Kyowa Interface Chemical Co., Ltd .: surface tension meter CBVP-A3). The glass transition temperature of the light emitting layer was 225 degreeC. In addition, although the material which has green light emission was used for this example, it is possible to produce a white organic EL element by laminating | stacking further using blue, red, and a dopant material.

(Formation of electron injection layer)
Subsequently, on the formed light emitting layer, LiF was used as an electron injection layer forming material under a vacuum environment condition of 5 × 10 ⁻⁴ Pa, except for a portion to become the extraction electrode 23a of the first electrode, by a vapor deposition method. A LiF layer (electron injection layer) having a thickness of 0.5 nm was stacked.

(Formation of second electrode)
Subsequently, on the formed electron injection layer, aluminum was used as a second electrode forming material under a vacuum of 5 × 10 ⁻⁴ Pa, and a mask pattern was formed by vapor deposition so as to have a takeout electrode. A second electrode having a thickness of 100 nm was laminated to produce an organic EL element substrate 1.

[Preparation of sealing substrate 1]
As the sealing substrate 1, a sheet-shaped sealing substrate having a two-layer structure using a polyethylene terephthalate film (manufactured by Teijin DuPont) as a substrate and an aluminum foil of a conductive material as a barrier layer was prepared. A polyethylene terephthalate film having a thickness of 100 μm and a barrier layer having a thickness of 7.0 μm were laminated in a long roll shape. The bonding between the substrate and the barrier layer was performed by a dry laminating method using a polyester adhesive, and the thickness of the sealed substrate after bonding was set to 110 μm. The water vapor permeability measured by the MOCON method mainly by the method based on JIS K-7129B method (1992) was 0.01 g / m ² · day. The oxygen permeability measured mainly by the MOCON method by a method based on JIS K7126B method (1987) was 0.1 ml / m ² · day · MPa.

[Transportation of organic EL element substrate 1 and sealing substrate 1 and processing of sealing substrate 1]
Using the production line for the sealing structure shown in FIG. 1, the organic EL element substrate 1 produced as described above and laminated in a roll shape is set as the organic EL element substrate feeding roll 3, and the sealing substrate is also laminated in a roll shape. 1 was set as a sealing substrate feed roll described in FIG.

Then, 2.0 m / min as the conveying speed _{V 1} of the organic EL device substrate 1, similarly transported while controlling so that 2.0 m / min as the conveying speed _{V 2} of the sealing substrate 1, according to FIG. 1 At position A, the position of the alignment mark is read by the CCD camera, and the position information is fed back to the cutting control unit provided on the transfer line of the sealing substrate, and the first electrode on the sealing substrate 1 according to the information. Then, the position of the extraction electrode of the second electrode is determined, and the upper / lower blade (90 ° blade) die set (for oscillating cut) described in FIG. 1 of JP-A-2004-58180 is used at that position. Electrode extraction openings 20A and 20B were formed at three locations with the arrangement shown in FIG.

(Formation of adhesive layer)
Next, from the adhesive layer forming portion 12 shown in FIG. 1, an ultraviolet curing liquid adhesive (epoxy resin system) is used as the adhesive layer coating solution, and the thickness is 30 μm in the region excluding the electrode extraction opening. An adhesive layer 13 was formed.

[Bonding of organic EL element substrate and sealing substrate]
Next, in the bonding unit 14, the organic EL element substrate 1 transported at the same speed between the pair of bonding rolls and the sealing substrate on which the adhesive layer 13 is formed are roll-bonded with a pressure of 0.1 MPa. And pasted together.

[Curing the adhesive layer]
Next, in the curing step 16, the adhesive layer is cured by irradiating a high-pressure mercury lamp having a wavelength of 365 nm as the curing means 17 with an irradiation intensity of 5 to 20 mW / cm ² and a distance of 10 mm for 1 minute, and the organic EL panel 1 is thus obtained. Produced.

<< Evaluation of organic EL panel 1 >>
The following evaluation was performed about the produced said organic EL panel 1. FIG.

[Evaluation of luminance unevenness resistance]
100 organic EL panels 1 were produced according to the above method, and the luminance unevenness (dark spot) resistance was evaluated according to the following method.

  Using a KEITHLEY source measure unit type 2400, a DC voltage was applied to each organic EL element to emit light. About 100 light emitting elements of the organic EL panel 1 that emitted light at 200 cd, the presence or absence of dark spots (brightness unevenness) was confirmed with a 50 × microscope, and the uneven brightness resistance was evaluated according to the following criteria.

◎: The number of organic EL panels in which dark spots are observed is 5 or less. ○: The number of organic EL panels in which dark spots are observed is 6 or more. △: The occurrence of dark spots is recognized. The number of organic EL panels to be produced is 11 or more and 20 or less. X: The number of organic EL panels in which dark spots are observed is 21 or more. As a result of evaluation by the above method, the luminance unevenness resistance of the organic EL panel 1 is , “◎”.

[Evaluation of electrode disconnection resistance]
100 organic EL panels 1 were produced according to the above method, and the electrode disconnection resistance was evaluated according to the following method.

  Using a source measure unit 2400 made by KEITHLEY, a direct current voltage is applied to each organic EL element to emit light, and the presence or absence of light emission is confirmed. At the same time, the presence or absence of disconnection of the extraction electrode portion is confirmed using a loupe. The electrode disconnection resistance was evaluated according to the standard.

  A: All organic EL panels emit light, and no disconnection of electrodes is confirmed.

○: Light emission was confirmed in all organic EL panels, but damage of the electrode part was confirmed in some organic EL panels by loupe observation. Δ: No light emission and electrode part in 1 to 3 organic EL panels ×: 4 or more organic EL panels were confirmed to have no light emission and damage to the electrode part. As a result of evaluation by the above method, the electrode disconnection resistance of the organic EL panel 1 was “「 ”. It was.

[Evaluation of machining accuracy of openings]
In the production of the organic EL panel 1, the processing of the opening for electrode extraction on the sealing substrate and the bonding process are performed by 1) 20 ° C., 20% RH, 2) 23 ° C., 55% RH, 3) 30 ° C., The measurement was performed under three environmental conditions of 80% RH, and the displacement of the formed electrode extraction opening relative to the position (reference position) of the extraction electrode was measured, and the processing accuracy of the opening was evaluated according to the following criteria.

◎: The deviation width of the electrode extraction opening position with respect to the reference position under the three environmental conditions is less than 2%. ○: The deviation width of the electrode extraction opening position with respect to the reference position under the three environmental conditions is , Both are 2% or more and less than 5%. Δ: In 3 environmental conditions, a condition that the deviation width of the position of the electrode extraction opening with respect to the reference position is 5% or more and less than 10%. : Among the three environmental conditions, the deviation width of the position of the electrode extraction opening with respect to the reference position is 10% or more. As a result of the evaluation by the above method, the processing accuracy of the opening of the organic EL panel 1 is , “◎”.

[Productivity of organic EL panels]
It was confirmed that the organic EL panel 1 of the present invention produced by the roll-to-roll method has high productivity (number of produced organic EL panels / unit time).

Comparative Example 1
<< Preparation of organic EL panel 2 >>
In the production of the organic EL panel 1 described in Example 1, the electrode extraction opening is not processed into the sealing substrate before the bonding step, as described in the example of Japanese Patent Application Laid-Open No. 2007-179783. Then, after bonding the organic EL element substrate and the sealing substrate, the organic EL panel 2 was produced in the same manner except that the lead portions of the first electrode and the second electrode were exposed using an ultrasonic cutter.

<< Evaluation of organic EL panel 2 >>
About the produced organic electroluminescent panel 2, it carried out similarly to the method of Example 1, and as a result of evaluating brightness nonuniformity tolerance, electrode disconnection tolerance, the processing precision of an opening part, and productivity, brightness nonuniformity tolerance was "(circle)". The processing accuracy of the opening was “◯” and the productivity was “「 ”, but the evaluation of the electrode disconnection resistance was“ Δ ”.

Comparative Example 2
<< Preparation of organic EL panel 3 >>
In the production of the organic EL panel 1 described in Example 1, as described in Japanese Patent Application Laid-Open No. 2007-194021, a single-wafer sealing substrate in which an electrode extraction opening has been processed in advance is used. The organic EL panel 3 was produced in the same manner except that the bonding with the organic EL element substrate was performed by the method.

<< Evaluation of organic EL panel 3 >>
About the produced organic electroluminescent panel 3, it carried out similarly to the method of Example 1, and as a result of evaluating brightness nonuniformity tolerance, electrode disconnection resistance, the process precision of an opening part, and productivity, brightness nonuniformity tolerance was "(circle)". The electrode disconnection resistance is “耐性”, the opening processing accuracy is “Δ”, and the productivity is “x”, which is inferior in terms of productivity.

Comparative Example 3
<< Preparation of organic EL panel 4 >>
In the production of the organic EL panel 1 described in Example 1, according to the information on the electrode arrangement of the organic EL element substrate, the position of the electrode by the alignment mark is obtained using a sealing substrate in which the electrode extraction opening is processed in the same condition in advance. The organic EL panel 4 was produced in the same manner except that the above information was not fed back.

<< Evaluation of organic EL panel 4 >>
About the produced organic electroluminescent panel 4, it carried out similarly to the method of Example 1, and as a result of evaluating brightness nonuniformity tolerance, electrode disconnection tolerance, the processing precision of an opening part, and productivity, brightness nonuniformity tolerance was "(circle)". The electrode disconnection resistance is “◎”, the opening processing accuracy is “×”, and the productivity is “◎”, resulting in lack of processing accuracy of the electrode extraction opening.

DESCRIPTION OF SYMBOLS 1 Organic EL element board | substrate 2 Organic EL element 3 Organic EL element board | substrate delivery roll 4 Alignment mark 5 Sealing board 6 Sealing board delivery roll 7 Alignment mark detection part 8 Feedback line 9 Cutting control part 10A Upper blade 10B Lower blade 11 Support roll DESCRIPTION OF SYMBOLS 12 Adhesive layer formation part 13 Adhesive layer 14 Bonding part 15 Bonding roll 16 Curing process 17 Curing means 18 Winding roll 19A, 19B Electrode 20A, 20B Electrode extraction opening 21 Organic EL panel 22 Flexible substrate 23 First electrode 23a Extraction electrode portion of first electrode 24 Organic functional layer 25 Second electrode 26 Light emitting region 27 Hole transport layer

Claims (6)

An organic electroluminescent element substrate in which an organic electroluminescent element having at least a first electrode, an organic functional layer including a light emitting layer, and a second electrode is formed on a long flexible substrate by a roll-to-roll method; In the manufacturing method of an organic electroluminescence panel in which a sealing structure is formed by pasting together a sealing substrate of
After forming the opening for electrode extraction on the flexible sealing substrate according to the electrode position information provided on the organic electroluminescence element substrate, the organic electroluminescence element substrate and the opening for electrode extraction were formed. A manufacturing method of an organic electroluminescence panel, wherein a sealing structure is formed by laminating a sealing substrate.   The organic electroluminescence element substrate has an alignment mark as position information. By detecting the alignment mark, the electrode position of the organic electroluminescence element substrate is specified, and the sealing substrate is attached to the sealing substrate according to the electrode position information. 2. The method for manufacturing an organic electroluminescence panel according to claim 1, wherein an opening for electrode extraction is formed.   3. The method of manufacturing an organic electroluminescence panel according to claim 2, wherein the method of detecting the alignment mark is an image recognition method using a CCD camera.   4. The method of manufacturing an organic electroluminescence panel according to claim 1, wherein a method of forming the electrode extraction opening in the sealing substrate is a cutting method using a cutting blade. 5. .   The said cutting blade is a punch die system which has arrange | positioned the upper blade and the lower blade up and down, The manufacturing method of the organic electroluminescent panel of Claim 4 characterized by the above-mentioned.   6. The organic electroluminescence panel according to claim 4, wherein the conveyance speed of the sealing substrate in the cutting step of forming the electrode extraction opening is synchronized with the conveyance speed of the organic electroluminescence element substrate. Production method.

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