JP2007200692A - Organic electro-luminescence panel and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an organic EL (electro-luminescence) panel in which performance of an organic EL element is not deteriorated when a sealing member is adhered through adhesives for manufacturing the organic EL panel to be sealed by adhesion-sealing, and to provide the organic EL panel. <P>SOLUTION: The organic EL panel has an adhesion-sealing structure formed by adhesion-sealing, with the sealing member through an adhesives layer, a top and a perimeter surface of a second electrode of the organic EL element. Further, the panel has a first electrode, an organic EL layer formed on the first electrode including at least one organic compound layer containing a light emitting layer, and the second electrode on a substrate in this order. A stress relaxation layer has an interface whose adhesive force with an adjacent layer is weak in comparison with an adhesive force between the second electrode and the organic EL layer, and is formed between the second electrode layer and the adhesives layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing an organic electroluminescence panel (hereinafter also referred to as an organic EL panel) and an organic EL panel produced by this production method.

  In recent years, organic EL elements using organic substances have been promising for use as solid light-emitting inexpensive, large-area full-color display elements and writing light source arrays, and active research and development have been promoted. The organic EL element includes a first electrode (anode or cathode) formed on a substrate, an organic compound layer (single layer portion or multilayer portion) containing an organic light emitting material laminated thereon, that is, a light emitting layer, It is a thin film type element having a second electrode (cathode or anode) laminated on the light emitting layer. When a voltage is applied to such an organic EL element, electrons are injected from the cathode and holes are injected from the anode into the organic compound layer. It is known that light is obtained by releasing energy as light when the electrons and holes recombine in the light emitting layer and the energy level returns from the conduction band to the valence band.

  As described above, since the organic EL element is a thin film type element, when an organic EL panel in which one or a plurality of organic EL elements are formed on a substrate is used as a surface light source such as a backlight, a surface light source. It is possible to easily make a device equipped with In addition, when a display device is configured using an organic EL panel in which a predetermined number of organic EL elements as pixels are formed on a substrate as a display panel, the liquid crystal display device has high visibility and no viewing angle dependency. There are benefits that cannot be obtained.

  By the way, organic substances such as organic light-emitting materials used in organic EL elements are weak against moisture and oxygen, and their performance deteriorates. Also, the characteristics of electrodes deteriorate rapidly in the atmosphere due to oxidation, so that these deteriorations can be prevented. In general, a sealing layer is provided as the uppermost layer.

  Many studies have been made on the organic EL element sealing method so far, and it is roughly classified into two methods, a casing type sealing method and a close contact type sealing method.

  The casing type sealing method is to seal an organic EL element by placing it in a case and blocking the outside, and filling the case with a predetermined gas or fluid for sealing together with the organic EL element. Is the method. The close-contact type sealing method is to seal by sealing the surface of an organic EL element formed on the substrate (behind the element when viewed from the substrate side) with an adhesive such as a glass plate. Is the method.

  In the case of the casing type sealing method, there is a problem that it cannot be made thin, requires a process for filling the case with a sealing gas or fluid, and is unsuitable for mass production. Therefore, a close-contact type sealing method has become the mainstream because it can be made thin, mass production is relatively easy, and a high sealing effect can be easily obtained.

As a sealing method of the adhesion type adhesive, for example, Japanese Unexamined 4-212284 discloses, GeO as described in JP-A-5-182759 Patent Publication, on the protective film made of an inorganic compound such as SiO _2, Light A method of fixing a glass substrate via a curable resin or the like is known. In JP 2001-307871 A, a barrier layer and a sealing film including a sealant layer made of a thermoplastic adhesive resin having a melt flow rate of 5 g / 10 min or more and 20 g / 10 min or less as defined in JIS K 7210 are tightly sealed. Organic EL elements are known.

However, in these methods, when the adhesive and the photo-curing resin are cured, the volume shrinks and thus a residual stress is generated. This residual stress is caused by the organic EL element to be sealed and the adhesive or photo-curing resin. Even if there is a film of GeO, SiO ₂ or the like between them, if the film thickness is as small as μm, it is transmitted to the organic EL. Since the residual stress is particularly strong at a portion having a small radius of curvature, the residual stress propagated to the organic EL element is concentrated on the end portion of the organic EL element. As a result, it is known that the electrode end of the element is crushed, and the anode and cathode come into contact with each other, causing a short circuit. This is a close-contact type sealing method using an adhesive and a photocurable resin. Measures for mitigating residual stress when an adhesive or a photocurable resin is cured have been studied. For example, a method is known in which a fluid stress relaxation layer is provided between an organic EL element and an adhesive, and a sealing material is fixed with the adhesive (see, for example, Patent Document 1). As an adhesive layer on the organic EL element, the adhesive shrinkage of the adhesive on the organic EL element side is set to two layers by using an adhesive smaller than the shrinkage ratio of the adhesive on the sealing material side to cure the adhesive. A method is known in which a sealing material is fixed with an adhesive so that the light emitting element is not affected by stress due to shrinkage (see, for example, Patent Document 2).

  However, although the method described in Patent Document 1 shows excellent performance in terms of the stress relaxation effect, it is difficult to increase the production efficiency because a complicated process is required to dispose the fluid stress relaxation layer. It is one.

  The close-contact type sealing method described in Patent Document 2 is relatively easy to mass-produce and can be applied to a thin organic EL element having a high sealing effect. Damage to the light-emitting element due to surface adhesion) is one of the factors that do not increase the production efficiency, and the response to the effect on the light-emitting element due to shrinkage during curing of the adhesive is insufficient It has become.

From such a situation, when manufacturing an organic EL element sealed with a close-contact type sealing method in which a sealing material is fixed via an adhesive, a method for manufacturing an organic EL element that does not cause performance deterioration of the organic EL element And development of organic EL elements is desired.
Japanese Patent Laid-Open No. 8-124777 JP 2003-109750 A

  The present invention has been made in view of the above circumstances, and its purpose is to produce an organic EL element when manufacturing an organic EL panel sealed by an adhesion type sealing method in which a sealing material is fixed through an adhesive. It is providing the manufacturing method of an organic electroluminescent panel and an organic electroluminescent panel which do not produce the performance degradation of this.

  The above object of the present invention has been achieved by the following constitution.

  1. An organic electroluminescent element having a first electrode on the substrate, an organic electroluminescent layer having at least one organic compound layer including a light emitting layer, and a second electrode in this order, on the second electrode and In the method of manufacturing an organic electroluminescence panel having a close sealing structure in which a peripheral surface is tightly sealed with a sealing member through an adhesive layer, adhesion between adjacent layers between the second electrode and the adhesive layer A method of manufacturing an organic electroluminescence panel, comprising forming a stress relaxation layer having an adhesion interface whose force is lower than an adhesion force between the second electrode and the organic electroluminescence layer.

  2. 2. The method for producing an organic electroluminescence panel according to 1 above, wherein the stress relaxation layer is composed of at least two layers.

  3. 3. The method for producing an organic electroluminescence panel according to item 1 or 2, wherein an adhesion interface of at least one layer of the stress relaxation layer has an adhesion interface lower than an adhesion force between the second electrode and the organic electroluminescence layer. .

  4). 4. The method of manufacturing an organic electroluminescence panel according to any one of 1 to 3, wherein the stress relaxation layer has a thickness of 1 nm to 10 μm.

  5. 5. The method for producing an organic electroluminescence panel according to any one of 1 to 4, wherein at least one layer of the stress relaxation layer is any one of organic compounds constituting the organic electroluminescence layer.

  6). The gas permeation preventive layer having a gas permeation preventive property is provided on the second electrode, between the stress relieving layer and on the stress relieving layer, 6. Manufacturing method of organic electroluminescence panel.

  7). 7. The organic electroluminescence panel as described in 6 above, wherein the gas permeation preventive layer has an adhesion interface whose adhesion force at the adhesion interface with the stress relaxation layer is lower than the adhesion force between the second electrode and the organic electroluminescence layer. Manufacturing method.

  8). 8. The substrate according to any one of 1 to 7, wherein the substrate and / or the sealing member is a flexible sealing member having a resin base material and a gas barrier layer. Manufacturing method of organic electroluminescence panel.

  9. 8. The method for producing an organic electroluminescence panel according to any one of 1 to 7, wherein the substrate and / or the sealing member is a glass plate.

  10. 8. The method for manufacturing an organic electroluminescence panel according to any one of 1 to 7, wherein the substrate and / or the sealing member is a metal sheet.

  11. An organic electroluminescent element having a first electrode on the substrate, an organic electroluminescent layer having at least one organic compound layer including a light emitting layer, and a second electrode in this order, on the second electrode and In the organic electroluminescence panel having an adhesion sealing structure in which a peripheral surface is closely sealed with a sealing member via an adhesive layer, the stress relaxation layer is provided between the second electrode and the adhesive layer, and the stress relaxation 2. The organic electroluminescence panel according to claim 1, wherein the layer has an adhesion interface in which an adhesion force between adjacent layers is lower than an adhesion force between the second electrode and the organic electroluminescence layer.

  12 12. The organic electroluminescence panel as described in 11 above, wherein the stress relaxation layer comprises at least two layers.

  13. 13. The organic electroluminescence panel according to 11 or 12, wherein an adhesion interface of at least one layer of the stress relaxation layer has an adhesion interface lower than an adhesion force between the second electrode and the organic electroluminescence layer.

  14 14. The organic electroluminescence panel according to any one of 11 to 13, wherein the stress relaxation layer has a thickness of 1 nm or more and 10 μm or less.

  15. 15. The organic electroluminescence panel according to any one of 11 to 14, wherein at least one layer of the stress relaxation layer is an organic compound constituting an organic compound layer of the organic electroluminescence layer.

  16. The gas permeation preventive layer having a gas permeation preventive property is provided on the second electrode, between the stress relieving layer and on the stress relieving layer. Organic electroluminescence panel.

  17. 17. The organic electroluminescence panel as set forth in 16, wherein the gas permeation preventive layer has an adhesive interface whose adhesive force at the adhesive interface with the stress relaxation layer is lower than the adhesive force between the second electrode and the organic electroluminescent layer. .

  18. 18. The organic material according to any one of 11 to 17, wherein the substrate and / or the sealing member is a flexible sealing member having a resin base material and a gas barrier layer. Electroluminescence panel.

  19. 18. The organic electroluminescence panel according to any one of 11 to 17, wherein the substrate and / or the sealing member is a glass plate.

  20. 18. The organic electroluminescence panel according to any one of 11 to 17, wherein the substrate and / or the sealing member is a metal sheet.

  Provided are an organic EL panel manufacturing method and an organic EL panel that do not cause deterioration in performance of an organic EL element when an encapsulant is fixed with an adhesive in order to manufacture an organic EL panel sealed by a close-contact type sealing method It was possible to produce high-quality thin and light organic EL panels.

  The embodiment of the present invention will be described with reference to FIGS. 1 to 8, but the present invention is not limited to this.

  FIG. 1 is a schematic cross-sectional view showing an example of a layer structure of an organic EL panel. FIG. 1A is a schematic cross-sectional view showing an example of a layer structure of an organic EL panel that does not have a gas permeation preventive layer between an organic electroluminescence layer and an adhesive layer. FIG.1 (b) is a schematic sectional drawing which shows an example of the laminated constitution of the organic electroluminescent panel which has a gas permeation prevention layer between an organic electroluminescent layer and an adhesive bond layer.

  A description will be given with reference to FIG. In the figure, 1 indicates an organic EL panel. The organic EL panel 1 includes a first electrode 102a, a hole transport layer (hole injection layer) 102b, a light emitting layer 102c, an electron injection layer 102d, an organic electroluminescence layer 102 on a substrate 101, a first electrode 102a, The two electrodes 103, the stress relaxation layer 104, the adhesive layer 105, and the sealing member 106 are provided in this order. The sealing member 106 is bonded onto the second electrode 103 and the peripheral surface of the second electrode 103 via the adhesive layer 105. The organic EL panel 1 shown in this figure is in close contact with the sealing member 106 through the adhesive layer 105 except for the external extraction electrode 102a1 of the first electrode 102a and the tip of the external extraction electrode 103a of the second electrode 103. It has a sealed structure.

  A description will be given with reference to FIG. The difference from FIG. 1A is that the gas permeation preventive layer 107 is provided between the second electrode 103 and the stress relaxation layer 104, and all other layer configurations are the same. The gas permeation preventive layer 107 can be provided as necessary, and the gas permeation preventive layer 107 may be provided on the second electrode 103, on the stress relaxation layer 104, or on the stress relaxation layer 104. This figure shows the case where it is provided on the second electrode 103.

  In the organic EL panel 1 shown in this figure, a hole injection layer (not shown) may be provided between the first electrode 102a and the hole transport layer 102b. Further, an electron transport layer (not shown) may be provided between the second electrode 103, the organic compound layer (light emitting layer) 104, and the electron injection layer 102d.

  The substrate 101 and / or the sealing member 106 is preferably a flexible sealing member, a glass plate, or a metal sheet having a resin base material and a gas barrier layer.

  The layer configuration of the organic EL panel shown in this figure shows an example, but the following configurations can be cited as the layer configuration of other typical organic EL elements.

(1) Substrate / first electrode (anode) / light emitting layer / electron transport layer / second electrode (cathode) / sealing member (2) substrate / first electrode (anode) / hole transport layer / light emitting layer / positive Hole blocking layer / electron transport layer / second electrode (cathode) / sealing member (3) substrate / first electrode (anode) / hole transport layer (hole injection layer) / light emitting layer / hole blocking layer / electron Transport layer / cathode buffer layer (electron injection layer) / second electrode (cathode) / sealing member (4) substrate / first electrode (anode) / anode buffer layer (hole injection layer) / hole transport layer / light emission Layer / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / second electrode (cathode) / sealing member In the case of an organic EL device, the first electrode (anode) 102a side is usually the observation side The first electrode (anode) 102a includes ITO (mixture of tin oxide and indium oxide), IZO (mixture of zinc oxide and indium oxide). ), ZnO, SnO ₂ , In ₂ O _{3 and the} like are known. Among them, the ITO electrode has a high light transmittance of 90% or more and a low sheet resistance value of 10Ω / □ or less, and is also used as a transparent electrode for liquid crystal displays and solar cells. Further, the IZO electrode has an advantage that a predetermined low resistance value can be obtained without heating the substrate at the time of formation, and the film surface is smoother than the ITO electrode.

  As shown in FIG. 1, the present invention cures an adhesive when manufacturing an organic EL element in which at least one organic EL element formed on a substrate is closely sealed with an adhesive using a sealing member. The present invention relates to an organic EL element manufacturing method and an organic EL element that are manufactured by providing a stress relaxation layer on a second electrode so that the light emitting element is not affected by the stress due to shrinkage.

  FIG. 2 is a partially enlarged schematic cross-sectional view of FIG. FIG. 2A is an enlarged schematic cross-sectional view of a portion indicated by T in FIG. FIG. 2B is an enlarged schematic cross-sectional view of a portion indicated by T ′ in FIG.

  This will be described with reference to FIG. The sealing member 106 is a flexible sealing member having a resin base 106a and a gas barrier layer 106b. A protective layer (not shown) may be provided on the gas barrier layer 106b (between the gas barrier layer 106b and the adhesive layer in this drawing). The resin substrate 106a may be a single body or a laminate, and can be appropriately selected as necessary. The gas barrier layer 106b may be a single body or a laminate, and can be appropriately selected as necessary.

  In this figure, the case where a flexible sealing member having a resin base material 106a and a gas barrier layer 106b is used as the sealing member 106 is shown. It is also possible to use a sheet.

  Reference numeral 104 a denotes an adhesive interface between the stress relaxation layer 104 and the adhesive layer 105, and 104 b denotes an adhesive interface with the second electrode 103. One of the adhesive force between the adhesive interface 104a and the adhesive layer 105 and the adhesive force between the adhesive interface 104b and the gas permeation preventive layer 107 is the second electrode 103 and the organic electroluminescence layer 102 (see FIG. 1). It is lower than the adhesive strength.

  This will be described with reference to FIG. Reference numeral 104 c denotes an adhesive interface between the stress relaxation layer 104 and the adhesive layer 105, and reference numeral 104 d denotes an adhesive interface with the gas permeation prevention layer 107. One of the adhesive force between the adhesive interface 104c and the adhesive layer 105 and the adhesive force between the adhesive interface 104d and the gas permeation prevention layer 107 is the second electrode 103 and the organic electroluminescent layer 102 (see FIG. 1). It is lower than the adhesive strength. Other reference numerals are the same as those in FIG.

  As shown in FIG. 2A, the adhesive force between the adhesive interface 104a and the adhesive layer 105, the adhesive force between the adhesive interface 104b and the second electrode 103, and the adhesion between the adhesive interface 104d and the gas permeation preventive layer 107. When the force is higher than the adhesive force between the second electrode 103 and the organic electroluminescent layer 102 (see FIG. 1), the stress when the adhesive layer 105 contracts by the curing process is propagated to the second electrode 103. This is not preferable because peeling occurs at the interface between the second electrode 103 and the electron injection layer 102d (see FIG. 1) constituting the organic electroluminescence layer 102 (see FIG. 1).

  The adhesive force of the adhesive interface 104a to the adhesive layer 105 and the adhesive force of either the second electrode 103 of the adhesive interface 104b are the second electrode 103 and the organic electroluminescent layer 102 (see FIG. 1). By lowering the adhesive strength of the adhesive layer 105 by the stress when the adhesive layer 105 contracts in the curing process, the interface between the adhesive interface 104a and the adhesive layer 105 or the interface between the adhesive interface 104b and the second electrode 103 is reduced. It is possible to suppress the propagation of stress when peeling occurs and the adhesive layer 105 contracts by the curing process, and the influence on the second electrode 103 can be prevented.

  As shown in FIG. 2 (b), the adhesive force between the adhesive interface 104c and the adhesive layer 105 and the adhesive force between the adhesive interface 104d and the gas permeation preventive layer 107 are determined by the second electrode 103 and the organic electroluminescence layer. 102 (see FIG. 1), the stress when the adhesive layer 105 contracts by the curing process affects the second electrode 103 through the gas permeation preventive layer 107, and the second electrode 103 and the above-described adhesive force. Since peeling occurs at the interface with the organic electroluminescence layer 102 (see FIG. 1), it is not preferable.

  The adhesive force between the adhesive layer 105 at the adhesive interface 104a and the gas permeation preventive layer 107 at the adhesive interface 104d is determined by the second electrode 103 and the organic electroluminescent layer 102 (see FIG. 1). Lower than the adhesive strength between the adhesive layer 105 and the gas permeation preventing layer 107 at the adhesive interface 104d or the interface with the adhesive layer 105 due to the stress when the adhesive layer 105 contracts in the curing process. Interfacial peeling occurs and the stress when the adhesive layer 105 contracts by the curing process can be relaxed, and the influence on the second electrode 103 can be prevented. Providing the gas permeation preventive layer 107 has an effect of suppressing deterioration of the organic electroluminescence element due to moisture, oxygen in the atmosphere, outgas generated from the adhesive or the stress relaxation layer, or the like.

  The stress relaxation layer 104 is preferably an organic compound of a layer composed of an organic compound among the layers constituting the organic electroluminescence layer 102 shown in FIG. Specifically, for example, in the case of the organic electroluminescence layer 102 shown in FIG. 1, a hole transport layer (hole injection layer) 102b, an organic compound layer (light emitting layer) 102c, and an electron injection layer 102d are formed. An organic compound is mentioned.

  The thickness of the stress relaxation layer 104 is preferably 1 nm or more and 10 μm or less in consideration of uniform interface formation and film formation time. The thickness of the gas permeation preventive layer 107 is preferably 1 nm or more and 10 μm or less in consideration of gas barrier properties, film formation time, and the like.

Examples of the gas permeation prevention layer 107 include an inorganic film, an organic film, or a hybrid film of both. As a characteristic of the gas barrier film, the water vapor permeability is preferably 0.01 g / m ² · day · atm or less. Furthermore, the oxygen permeability is preferably 10 ⁻³ ml / m ² / day or less, and the water vapor permeability is 10 ⁻⁵ g / m ² / day or less.

  As a material for forming the gas barrier film, any material may be used as long as it has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. 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 gas barrier film is not particularly limited. For example, the vacuum deposition method, the sputtering method, the reactive sputtering method, the molecular beam epitaxy method, the cluster ion beam method, the ion plating method, the plasma polymerization method, the atmospheric pressure plasma weighting. A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

  FIG. 3 is an enlarged schematic cross-sectional view when the stress relaxation layer shown in FIG.

  The stress relaxation layer 104 preferably has at least two layers, and this figure shows a case where the stress relaxation layer 104 is composed of two layers of a first layer 104e and a second layer 104f. The stress relaxation layer 104 shown in the figure includes an adhesion interface 104g between the first layer 104e and the second electrode 103, an adhesion interface 104h between the first layer 104e and the second layer 104f, a second layer 104f, and an adhesive layer. 105 and an adhesive interface 104i.

  Any one of the adhesive force between the adhesive interface 104g and the second electrode 103, the adhesive force between the adhesive interface 104h and the second layer 104f, and the adhesive force between the adhesive interface 104i and the adhesive layer 105 is the second electrode 103 and the organic layer. It is preferably lower than the adhesive strength with the electroluminescent layer 102 (see FIG. 1).

  The thickness of the first layer 104e is preferably 1 nm or more and 10 μm or less in consideration of uniform interface formation, film formation time, and the like.

  The first layer 104e and the second layer 104f of the stress relaxation layer 104 shown in this figure constitute the organic electroluminescence layer 102 shown in FIG. 1 in the same manner as the single layer stress relaxation layer 104 shown in FIG. Of each layer, the organic compound is preferably a layer composed of an organic compound. The organic compounds constituting the first layer 104e and the second layer 104f may be the same or different. Specifically, for example, when the first layer 104e is the hole transport layer (hole injection layer) 102b of the organic electroluminescence layer 102 shown in FIG. 1, the second layer 104f is the light emitting layer 102c or the electron injection layer 102d. The organic compound which comprises is mentioned.

  As shown in this figure, the stress relaxation layer 104 is at least two layers, and any one of the adhesion forces between the adhesion interface of each stress relaxation layer and the adjacent layer is the second electrode 103 and the organic electroluminescence layer 102 (FIG. 1)), the stress when the adhesive layer 105 contracts during the curing process can be more reliably relaxed, and the influence on the second electrode 103 can be prevented. Is possible.

  FIG. 4 is an enlarged schematic cross-sectional view of a portion indicated by T in FIG. 1 when the stress relaxation layer shown in FIG. FIG. 4A is an enlarged schematic cross-sectional view when the stress relaxation layer shown in FIG. 2B is composed of two layers. FIG. 4B is an enlarged schematic cross-sectional view when the gas permeation preventive layer shown in FIG. 4A is provided with a gas permeation preventive layer on the first layer of the stress relaxation layer. FIG. 4C is an enlarged schematic view of the portion indicated by T in FIG. 1 when the gas permeation preventive layer shown in FIG. 4A is provided between the first layer and the second layer of the stress relaxation layer. It is sectional drawing.

  A description will be given with reference to FIG. The stress relaxation layer 104 shown in the figure includes an adhesive interface 104j between the first layer 104e and the gas permeation preventive layer 107, an adhesive interface 104k between the first layer 104e and the second layer 104f, a second layer 104f, and an adhesive. And an adhesive interface 104 l with the layer 105.

  Any one of the adhesive force between the adhesive interface 104j and the gas permeation preventive layer 107, the adhesive force between the adhesive interface 104k and the second layer 104f, and the adhesive force between the adhesive interface 104l and the adhesive layer 105 is the second electrode 103 and the adhesive layer 105. It is preferable that it is lower than the adhesive force with the organic electroluminescent layer 102 (refer FIG. 1).

  A description will be given with reference to FIG. The stress relaxation layer 104 shown in the figure includes an adhesion interface 104m between the first layer 104e and the second electrode 103, an adhesion interface 104n between the first layer 104e and the second layer 104f, and a gas permeation prevention between the second layer 104f and the second layer 104f. An adhesive interface 104o with the layer 107;

  Any one of the adhesive force between the adhesive interface 104m and the second electrode 103, the adhesive force between the adhesive interface 104n and the second layer 104f, and the adhesive force between the adhesive interface 104o and the gas permeation prevention layer 107 is the second electrode 103 and the second electrode 103. It is preferable that it is lower than the adhesive force with the organic electroluminescent layer 102 (refer FIG. 1).

  A description will be given with reference to FIG. In the stress relaxation layer 104 shown in this figure, the first layer 104e and the second layer 104f are separated from each other, and the gas permeation preventing layer 107 is provided between the first layer 104e and the second layer 104f.

  The first layer 104e has an adhesion interface 104p with the second electrode 103 and an adhesion interface 104q with the gas permeation prevention layer 107. The second layer 104 f has an adhesive interface 104 r with the gas permeation preventive layer 107 and an adhesive interface 104 s with the adhesive layer 105.

  The adhesive force between the adhesive interface 104p and the second electrode 103, the adhesive force between the adhesive interface 104q and the gas permeation preventive layer 107, the adhesive force between the adhesive interface 104r and the gas permeation preventive layer 107, the adhesive interface 104s and the adhesive layer 105 It is preferable that any one of these adhesive strengths is lower than the adhesive strength between the second electrode 103 and the organic electroluminescent layer 102 (see FIG. 1).

  As shown in the figure, the stress relaxation layer 104 is at least two layers, and the gas permeation prevention layer 107 is provided on the second electrode, between the stress relaxation layer and the stress relaxation layer, and each stress relaxation layer. The adhesive layer 105 is cured by making any one of the adhesive forces between the adhesive interface and the adjacent layer lower than the adhesive force between the second electrode 103 and the organic electroluminescent layer 102 (see FIG. 1). It is possible to more surely relieve the stress when shrinking due to, and it is possible to prevent the influence on the second electrode 103, and the generation of moisture, oxygen, adhesives and stress relaxation layers in the atmosphere occurs. It becomes possible to suppress deterioration of the organic EL element due to outgas or the like.

  FIG. 5 is a schematic view of a method for producing an organic EL element using a single substrate.

  In the figure, 2 indicates a manufacturing apparatus. Reference numeral 201 denotes a supply unit that supplies the single-wafer substrate 201a to the process. Reference numeral 202 denotes a substrate cleaning apparatus for cleaning the surface of the single-wafer substrate 201a in order to improve the vapor deposition property before the first electrode is vapor-deposited on the surface of the single-wafer substrate 201a supplied from the supply unit 201. . Reference numeral 203 denotes a first electrode forming vapor deposition apparatus for forming the first electrode a on the single wafer substrate 201a after the cleaning process. Reference numeral 204 denotes a hole transport layer forming vapor deposition apparatus for forming the hole transport layer b on the first electrode a of the single substrate 201a on which the first electrode a is formed. Reference numeral 205 denotes a light emitting layer forming vapor deposition apparatus for forming a light emitting layer c on the hole transport layer b of the single wafer substrate 201a on which the hole transport layer b is formed. Reference numeral 206 denotes an electron injection layer forming vapor deposition apparatus for forming an electron injection layer d on the light emitting layer c of the single substrate 201a on which the light emitting layer c is formed. Reference numeral 207 denotes a second electrode forming vapor deposition apparatus for forming the second electrode e on the electron injection layer d of the single-wafer substrate 201a on which the electron injection layer d is formed, and 208 is a gas permeation prevention device on the second electrode e. 1 shows a gas permeation prevention layer forming vapor deposition apparatus for forming a layer f. Reference numeral 209a denotes a first layer stress relaxation layer forming vapor deposition apparatus for forming the first layer g of the stress relaxation layer on the gas permeation preventive layer f. Reference numeral 209b denotes a second layer stress relaxation layer forming vapor deposition apparatus for forming the second layer h of the stress relaxation layer on the first layer g of the stress relaxation layer. Reference numeral 210 denotes a collection unit. Since the first electrode formation vapor deposition apparatus 203 to the second layer stress relaxation layer formation vapor deposition apparatus 209b all have the same configuration, the configuration of the first layer stress relaxation layer formation vapor deposition apparatus 209a is representative. Will be described in detail with reference to FIG.

  In this figure, the gas permeation prevention layer forming vapor deposition apparatus 208, the first layer stress relaxation layer forming vapor deposition apparatus 209a, and the second layer stress relaxation layer forming vapor deposition apparatus 209b form the configuration shown in FIG. Shows when to do. The arrangement among the gas permeation prevention layer forming vapor deposition apparatus 208, the first layer stress relaxation layer forming vapor deposition apparatus 209a, and the second layer stress relaxation layer forming vapor deposition apparatus 209b is not particularly limited, and as required. Can be changed.

  For example, in the case of the configuration shown in FIG. 2A, the gas permeation preventing layer forming vapor deposition apparatus 208 and the second layer stress relaxation layer forming vapor deposition apparatus 209b can be formed without using them. In the case of the configuration shown in FIG. 2B, it is possible to form without using the second layer stress relaxation layer forming vapor deposition apparatus 209b. In the case of the configuration shown in FIG. 3, the gas permeation prevention layer forming vapor deposition apparatus 208 can be formed without using it. In the case of the configuration shown in FIG. 4B, the second layer stress relaxation layer forming vapor deposition apparatus 209b, the first layer stress relaxation layer forming vapor deposition apparatus 209a, and the gas permeation prevention layer forming vapor deposition apparatus 208 are arranged in this order. By doing so, it can be formed. In the case of the configuration shown in FIG. 4C, the second layer stress relaxation layer forming vapor deposition apparatus 209b, the gas permeation prevention layer forming vapor deposition apparatus 208, and the first layer stress relaxation layer forming vapor deposition apparatus 209a are arranged in this order. By doing so, it can be formed.

  This figure shows the case where the first layer stress relaxation layer forming vapor deposition apparatus 209a and the second layer stress relaxation layer forming vapor deposition apparatus 209b are separately provided in series. When using the same organic compound as the organic compound constituting the luminescent layer, it is possible to form a stress relaxation layer using a hole transport layer forming vapor deposition apparatus and a light emitting layer forming vapor deposition apparatus. is there. Thereby, it is possible to form a stress relaxation layer without extending the process.

  6 is a schematic diagram of the first layer stress relaxation layer forming vapor deposition apparatus shown in FIG. FIG. 6A is an enlarged schematic view of the first layer stress relaxation layer forming vapor deposition apparatus shown in FIG. FIG. 6B is a schematic block diagram showing the relationship between each part and each means constituting the first layer stress relaxation layer forming vapor deposition apparatus.

  In the figure, reference numeral 209a denotes a first layer stress relaxation layer forming vapor deposition apparatus. The first layer stress relaxation layer forming vapor deposition apparatus 209a includes a vapor deposition chamber A, a substrate holding unit B, a mask arranging unit C, a raw material evaporation unit D, and a control unit E.

A1 indicates an exhaust port provided in the vapor deposition chamber A, and is connected to an exhaust means (not shown) which is a decompression means. The vacuum degree is set to the vapor deposition chamber A via the main valve A2. . The degree of vacuum in the vapor deposition chamber A can be appropriately set as necessary. A3 shows a vacuum degree meter which is a measuring means for measuring the vacuum degree of the vapor deposition chamber A. There is no limitation in particular as a vacuum measuring meter, For example, an ionization vacuum gauge and a Pirani vacuum gauge are mentioned. A4 indicates an inert gas inlet, and an inert gas such as N ₂ , Ar, Ne, or He is introduced as an atmospheric gas via a gas inlet valve A5 as necessary.

  The substrate holding means B has a substrate holding member B1, a temperature measuring means B2, and a temperature control mechanism B3, and the temperature can be controlled by the temperature control mechanism B3. A plurality of substrates 201a (see FIG. 3) on which the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) held by the substrate holding member B1 is formed may be arranged. It can be arranged at any position of the substrate holding member B1. The substrate holding member B1 is not particularly limited as long as the planarity of the substrate can be held and held, and examples thereof include stainless steel and aluminum.

  The temperature measurement unit B2 measures the temperature of the substrate 201a on which the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) disposed on the substrate holding member B1 is formed, and the result is a control unit. Feedback to E. By controlling the temperature control mechanism B3 that circulates the heat medium to the substrate holding member B1 according to the fed back information, the temperature of the substrate can be kept constant while the raw material is being deposited on the substrate. Yes. There is no limitation in particular as temperature measurement means B2, For example, a thermocouple, a temperature sensor, etc. are mentioned.

  B4 indicates a rotating means for rotating the substrate holding member B1. The rotating means is not particularly limited, and may be, for example, a rotary motor or a belt via a pulley. This figure shows the case of a rotary motor. The substrate holding member B1 may be rotated or fixed, but it is preferable to rotate in consideration of film formation uniformity.

  The mask placement means C includes a mask placement member C1, a temperature measurement means C4, and a temperature control mechanism C5, and the temperature control mechanism C5 can control the temperature. The temperature measuring means C4 is preferably the same as the temperature measuring means B2 arranged on the substrate holding member B1.

  C3 indicates a mask arranged on the mask arrangement member C1. The mask placement member C1 is not particularly limited as long as the planarity of the mask C3 can be maintained and placed, and examples thereof include stainless steel, aluminum, copper, and the like. The mask arrangement member C1 is attached to the substrate holding member B1.

  A6 is a raw material deposition control for controlling the deposition of the raw material (first layer stress relaxation layer raw material) on the substrate 201a on which the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) is formed. The shielding plate of a means is shown. The shield plate A6 may be of any type, but as a function, the shield plate A6 can be completely closed to the substrate 201a on which the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) is formed. A type that can completely prevent vapor deposition is preferred. Note that the shielding plate shown in this figure is of an open / close type and can be controlled to open / close. A7 shows the drive means of shielding board A6.

  The temperature control mechanism B3 includes a medium temperature control means (not shown) that can be heated and cooled, and a medium that can be heated and cooled, the substrate holding member B1 of the substrate holding means B, and the mask arrangement member C1 of the mask arrangement means C. Circulation means (not shown) for circulation to the medium and circulation amount control means (not shown) for the circulation amount of the medium. By circulating a medium controlled to a predetermined temperature to the substrate holding member B1 and the mask arrangement member C3 by the temperature control mechanism B3, the second electrode 103 (see FIG. 2) or gas barrier layer arranged on the substrate holding member B1. The substrate 201a on which up to 107 (see FIG. 2) and the mask C3 arranged on the mask arrangement member C1 can be set to a predetermined temperature.

  Examples of the medium include synthetic organic heat medium oil. Examples of the medium temperature control means include a combination of a heater and a chiller. Examples of the circulation amount control means include a combination of a flow meter and a pump.

  The raw material evaporation means D is disposed in the lower part of the vapor deposition chamber A corresponding to substantially the center of the deposited film formation region, and includes a raw material container D1 having heating means (not shown), and a raw material (first layer) in the raw material container D1. Stress relaxation layer forming raw material) Raw material temperature measuring means D3 for measuring the temperature of D2, current supply part D4 for heating the raw material container D1, and opening ratio for controlling the opening ratio of the opening D5 of the raw material container D1 And a lid D6 of the control means. The shape of the raw material container D1 is not particularly limited, and examples thereof include a line type and a spot type, and the number to be arranged can be appropriately selected depending on the size of the substrate 201a. The number of raw material containers D1 is not particularly limited, and a plurality of raw material containers D1 may be arranged at different positions. The heating means for the material container D1 is not particularly limited, and examples thereof include a sputtering method, a resistance heating method, and an ion beam method. This figure shows the resistance heating method. The lid D6 may have any shape, and may not have a shape that covers all the mouths of the raw material evaporation means. The lid D6 is preferably a controllable movable lid in order to obtain a stable deposited film surface until the raw material D2 reaches a set temperature. D7 indicates a moving means for moving the lid D6.

  It is preferable to feed back the result of the raw material temperature measuring means D3 to the control means E, and perform control processing so as to maintain the set temperature by performing arithmetic processing on the set temperature previously input to the control means E. By combining these controls with the control of the movable lid D6, it is possible to perform control such that the lid is opened when the set temperature is reached.

  The raw material (first layer stress relaxation layer forming raw material) D2 in the raw material container D1 is preferably the same organic compound as the organic compound forming the organic electroluminescence layer.

  In this figure, the raw material evaporation means D is disposed in the lower part of the vapor deposition chamber A corresponding to substantially the center of the deposited film formation region, but the position of the raw material evaporation means D is not particularly limited. In the case of the first electrode formation vapor deposition apparatus 203 to the second layer stress relaxation layer formation vapor deposition apparatus 209b shown in FIG. 3, they can be arranged at different positions as required.

  The relationship between each part and each means constituting the first layer stress relaxation layer forming vapor deposition apparatus 209a will be described with reference to a schematic block diagram shown in FIG. Information on the temperature of the substrate 201a held by the substrate holding means B measured by the substrate temperature measuring means B2 is input to the CPU of the control means E. The information input to the control means E performs a calculation process with the preset temperature previously input to the memory, and a temperature control mechanism B3 disposed in the substrate holding means B for circulating the heat medium adjusted to a predetermined temperature. It is possible to control the circulation amount of the medium and the temperature of the medium.

  Information on the temperature of the mask C3 held by the mask placement member C1 measured by the mask temperature measuring means C4 is input to the CPU of the control means E. The information input to the control means E performs a calculation process with the preset temperature input in advance in the memory, and a temperature control mechanism C5 that circulates the medium adjusted to a predetermined temperature disposed in the mask placement member C1. It is possible to control and control the circulation amount of the heat medium and the temperature of the heat medium. At this time, the circulation amount of the medium by the temperature control mechanism C5 and the temperature of the medium match the temperature history of the substrate 201a on which the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) is formed. In this method, the temperature of the mask C3 is controlled.

  The result of the raw material D2 in the raw material container D1 measured by the raw material temperature measuring means D3 is fed back to the control means E, and the arithmetic processing is performed on the set temperature input in advance to the control means E, and the result is arranged in the raw material container D1 The temperature of the raw material D2 can be controlled to be constant by adjusting the current of the current supply unit D4 of the heating means (not shown). By maintaining the temperature of the raw material D2 at a specified temperature, the second electrode 103 of the substrate 201a formed until the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) is formed. A material having a substantially constant temperature is vapor-deposited on the gas barrier layer 107 (see FIG. 2) or on the gas barrier layer 107 (see FIG. 2), so that a stable first layer stress relaxation layer can be formed.

  Information regarding the amount of the raw material D2 in the raw material container D1 converted according to time is input to the CPU of the control means E. The information input to the control means E performs the calculation process with the amount of the raw material D2 in the raw material container D1 previously input to the memory, operates the moving means (attached illustration) D7, and moves the lid D6 of the raw material container D1. It is possible to change the aperture ratio. For example, the opening ratio is 100% when the amount of the raw material D2 in the raw material container D1 is 100%, and 50% when the amount of the raw material D2 in the raw material container D1 is 50%.

  By keeping the deposition rate of the raw material D2 substantially constant, the second electrode of the substrate 201a formed until the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) is formed. A constant source material D2 is vapor-deposited on 103 (see FIG. 2) or on the gas barrier layer 107 (see FIG. 2), and a stable first layer stress relaxation layer can be formed.

  Information on the temperature of the raw material D2 in the raw material container D1 measured by the raw material temperature measuring means D3 is input to the CPU of the control means E. The information input to the control means E performs a calculation process with the raw material deposition start temperature input in advance in the memory, and operates the driving means A7 to open and close the shielding plate A6. It is possible to prevent vapor deposition on the substrate 201a formed until the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) in an unstable heating stage is formed. . For example, after at least 30 seconds have elapsed since the difference between the raw material deposition start temperature inputted in advance and the temperature of the raw material D2 in the raw material container D1 measured by the raw material temperature measuring means D3 becomes −10 to + 10 ° C., the shielding plate It is preferable to open and close when it reaches 20 ° C or higher.

  In addition, the temperature measurement result of the raw material D2 is obtained from the temperature control mechanism B3 and mask C3 of the substrate 201a on which the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) is formed. The heating start timing of the substrate 201a and the mask C3 formed until the second electrode 103 (see FIG. 2) or the gas barrier layer 107 (see FIG. 2) is formed by feeding back to the temperature control mechanism C5 of FIG. Of course, it can also be used to determine.

  FIG. 7 is a schematic view of a manufacturing process of an organic EL panel that is tightly sealed with a sealing member. The manufacturing process shown in the figure shows a case where an adhesive is disposed on the sealing member.

  In the figure, 3 indicates a manufacturing process. In the manufacturing process 3, the first supply process 301 of the sealing member 301a, the second supply process 302 of the organic EL element 302a, the adhesive arrangement process 303, the sealing member 301a and the organic EL element 302a are bonded to each other. It has the bonding process 304 which bonds through, the collection | recovery process 305, and the washing | cleaning process 306. The organic EL element 302a is manufactured by a method using the vapor deposition apparatus shown in FIG. 3, and has a configuration shown in FIG.

  The first supply step 301 is a supply robot 301c having a storage box 301b of a single-sealed sealing member 301a cut to the size of the organic EL element 302a and a suction plate 301c1 for taking out the sealing member 301a from the storage box 301b. have. The supply robot 301c can move in the vertical direction (arrow A direction in the figure), move in the horizontal direction (arrow B direction in the figure), and rotate (arrow C direction in the figure).

  The sealing member 301 a taken out from the storage box 301 b by the supply robot 301 c is placed on the placing table 307. The mounting table 307 preferably has suction means (not shown) for fixing the mounted sealing member 301a. Further, it is possible to move in the X-axis and Y-axis directions and change the angle for alignment when the adhesive is placed on the sealing member 301a in the adhesive placement step 303. The sealing member 301a is placed on the mounting table 307 and fixed, and then sent to the cleaning step 306 by the moving means. The mounting table 307 can be sequentially moved from the first supply process 301 to the bonding process 304 along the guide rail 308 by a moving means (not shown). When the mounting table 307 is moved to each process by the moving means, each process is provided with a detection device (not illustrated) that detects an alignment mark (not illustrated) attached to the mounting table 307. It is controlled so as to stop at a specified position in the main body according to the information shown in the figure. The type of the detection device (not shown) is not particularly limited, and examples thereof include image recognition means using a CCD camera.

  The cleaning step 306 is arranged between the first supply step 301 and the adhesive placement step 303, and the surface of the sealing member 301a on which the adhesive is placed is cleaned before the adhesive is placed. Is called. It is preferable to dispose a charge removing means (not shown) before or in the cleaning process 306, and in particular, a non-contact type charge removing means (not shown) is more preferable to avoid generation of dust due to contact, Examples thereof include a corona discharge ionizer, a soft X-ray ionizer, and an ultraviolet irradiation ionizer.

  The cleaning process 306 includes a cleaning device 306a, and the cleaning device 306a is preferably a dry cleaning method. For example, air spraying, ultrasonic air spraying, a combination of air spraying and suctioning methods, ultrasonic air spraying and suctioning methods can be used. A combined use system, an adhesive roll system, etc. are mentioned. In the case of this figure, the case of the combined method of air blowing and a suction method is shown. After the cleaning in the cleaning process 306, the moving means (not shown) moves to the adhesive placement process 303 in a state of being mounted on the mounting table.

An example of conditions for cleaning the sealing member by the cleaning device 306a will be described below. 1) In the case of a sealing member composed of a resin base material and a gas barrier layer, the cleaning conditions include a gas blowing air volume of 5.5 m ³ / min, a gas blowing air speed of 100 m / sec, and a time of 3 minutes. 2) When the sealing member is a glass plate, cleaning conditions include a gas blowing rate of 7 m ³ / min, a gas blowing rate of 140 m / sec, and a time of 3 minutes. 3) In the case where the sealing member is a metal sheet, the cleaning conditions include a gas blowing rate of 8 m ³ / min, a gas blowing rate of 150 m / sec, and a time of 3 minutes. The gas blowing air volume is a value obtained by measuring the air volume in the gas supply pipe with a flow meter and the cross-sectional area of the gas supply pipe. The gas blowing wind speed indicates an average wind speed value of the gas blowing portion calculated from the air volume and the nozzle cross-sectional area.

  The arrangement process 303 includes an adhesive arrangement device 303a. As the arrangement device 303a, the adhesive to be used may be a melt type or a sheet type, so that it can correspond to the type of the adhesive. For example, when the adhesive is a melt type, a photocuring and thermosetting sealing agent having a reactive vinyl group of an acrylic acid oligomer, a methacrylic acid oligomer, a moisture curing type sealing agent such as 2-cyanoacrylate, Examples thereof include epoxy-based heat and chemical curing type (two-component mixed) sealing agents, cationic curing type ultraviolet curing epoxy resin sealing agents, and the like. Among these, it is preferable to apply a cationic curing type ultraviolet curable epoxy resin sealant by screen printing in consideration of production efficiency and film thickness stability.

  In the case of a sheet-like type, a sheet-like sealing agent and a thermoplastic resin are exemplified. The sheet-like sealant refers to a sealant that is non-flowable at room temperature (about 25 ° C.) and exhibits fluidity in the range of 50 ° C. to 100 ° C. when heated and is formed into a sheet shape. Examples of the sealant to be used include a photocurable resin mainly composed of a compound having an ethylenic double bond at the molecular end or side chain and a photopolymerization initiator. 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. The thermoplastic resin is not particularly limited as long as it satisfies the above numerical values. For example, low-density polyethylene (LDPE), HDPE, which is a polymer film described in Toray Research Center, Inc., a new development of functional packaging materials. , 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 (EVOH) ), Ethylene-propylene copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, vinylidene chloride (PVDC), and 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. As the arrangement method, various generally known methods such as a wet lamination method, a dry lamination method, a hot melt lamination method, an extrusion lamination method, and a thermal lamination method can be used.

  The thickness of the adhesive to be arranged is preferably 5 to 100 μm in consideration of the curing reaction time, the influence on the organic layer, the moisture penetration from the edge, etc. for both the melt type and the sheet type.

  After placing the adhesive on the sealing member, the adhesive is moved to the laminating step 304 along the guide rail 308 by a moving means (not shown) while being placed on the placing table 307.

  The second supply process 302 includes a supply robot 302c including a shelf-type storage box 302b for the organic EL elements 302a and two extraction arms 302c1 for extracting the organic EL elements 302a from the shelf-type storage box 302b. The take-out arm 302c1c moves in the horizontal direction (arrow D direction in the figure) and holds the organic EL element on the mounting table 309 in order to hold both ends of the organic EL element 302a stored and stored in the shelf-type storage box 302b. In order to place 202a and to take out the organic EL element 302a housed in the lower stage from the upper stage of the shelf type storage box 302b, it is possible to move in the vertical direction (arrow E direction in the figure). The organic EL element 302a taken out from the shelf-type storage box 302b by the supply robot 302c is placed on the placing table 309 and moved to the bonding step 304 by the moving means (not shown) along the guide rail 308. The surface of the organic EL element 302a stored in the shelf-type storage box 302b (the surface on which the sealing material is bonded) is facing downward. The mounting table 309 holds the four end sides of the organic EL element 302a, and the center part is a cavity to avoid damage due to contact with the surface of the organic EL element 302a.

The bonding step 304 includes a supply robot 304a, a bonding device 304b, and a curing processing device 304c. The supply robot 304a has the same mechanism and function as the supply robot 302c, and moves in the vertical direction (arrow F direction in the figure), moves in the horizontal direction (arrow G direction in the figure), and rotates (in the figure). Movement in the direction of arrow H) is possible. In the bonding step 304, the second electrode of the organic EL element 302a in a state of being mounted on the mounting table 309 by the supply robot 304a onto the surface of the adhesive 301a1 of the sealing member 301a mounted on the mounting table 307. The sides are overlapped, and thereafter bonded by a bonding apparatus 304b and processed by a curing apparatus 304c, whereby the sealing of the organic EL element 302a by the sealing member 301a is completed, and an organic EL panel is manufactured. After the close sealing has been completed, it is recovered in the recovery step 305. Incidentally, the surface pressure at the time of bonding by the bonding apparatus 304b, the flexible sealing member bonded condensable, damage or the like of the organic EL element is ^{considered, 0.5 × 10 4 Pa~9.8 × 10} 4 Pa is preferred. It is preferable to perform bonding by the bonding apparatus 304b in a reduced pressure environment of 1 Pa to 30 kPa in consideration of air bubbles.

  The curing processing device 304c can be changed according to the type of adhesive used. For example, when the adhesive is a thermosetting type, it becomes a curing processing apparatus having a heating device, and when it is an ultraviolet curing type, it becomes a curing processing apparatus having an ultraviolet irradiation device. Depending on the curing time and tact of the selected adhesive, the curing processing device 304c can be used as a temporary curing device and a main curing device. In addition, although the case where the bonding apparatus 304b and the hardening processing apparatus 304c are isolate | separated is shown in this figure, it is also possible to give the function of the hardening processing apparatus 304c to the bonding apparatus 304b. From the viewpoint of life reduction due to deterioration of the organic EL element, it is important that the water concentration and the oxygen concentration are low until the above-described curing processing by the curing processing device 304c. It is preferable to carry out below.

  FIG. 8 is a schematic view of another manufacturing process of an organic EL panel that is tightly sealed with a sealing member. The manufacturing process shown in this figure shows a case where an adhesive is disposed on the organic EL element.

  In the figure, 4 indicates a manufacturing process. In the manufacturing process 4, the second supply process 401 of the organic EL element 401a, the first supply process 402 of the sealing member 402a, the adhesive disposing process 403, the organic EL element 401a and the sealing member 402a are bonded to each other. It has the bonding process 404 which bonds through, the collection | recovery process 405, and the washing | cleaning process 406. The organic EL element 401a is manufactured by a method using the vapor deposition apparatus shown in FIG. 3, and has a configuration shown in FIG.

  The second supply process 401 includes a supply robot 401c including a shelf-type storage box 401b for the organic EL elements 401a and two extraction arms 401c1 for extracting the organic EL elements 401a from the shelf-type storage box 401b. The take-out arm 401c1c moves in the horizontal direction (in the direction of arrow I in the figure) and holds the organic EL element on the mounting table 407 in order to hold both ends of the organic EL element 401a stored and stored in the shelf-type storage box 401b. In order to place 401a and to take out the organic EL element 401a housed in the lower stage from the upper stage of the shelf-type storage box 401b, it is possible to move in the vertical direction (direction of arrow J in the figure). The organic EL element 401a taken out from the shelf-type storage box 401b by the supply robot 401c is mounted and fixed on the mounting table 407 with the surface (the surface of the second electrode) facing upward, and then moved by a moving means (not shown). Along the guide rail 408, the adhesive is sent to the adhesive placement step 403 by the moving means. The surface of the organic EL element 401a stored in the shelf-type storage box 401b (the surface of the second electrode) is facing upward. The mounting table 407 has the same mechanism and function as the mounting table 307 shown in FIG.

  The placement step 403 includes an adhesive placement device 403a. The placement device 403a is the same as the placement device 303a shown in FIG. 7, and the same adhesive is used. After the adhesive is disposed on the organic EL element 401a, the adhesive is moved to the bonding step 404 along the moving guide rail 408 by a moving means (not shown) while being mounted on the mounting table.

  The first supply process 402 is a supply robot 402c including a storage box 402b of a single-sealed sealing member 402a cut to the size of the organic EL element 401a, and a suction plate 402c1 for taking out the sealing member 402a from the storage box 402b. have. The supply robot 402c has the same mechanism and function as the supply robot 301c shown in FIG. The sealing member 402a taken out from the storage box 402b by the supply robot 402c is placed on the placing table 409 and sent to the cleaning step 406 by the moving means. The mounting table 409 preferably has the same structure as the mounting table 307 shown in FIG.

  The cleaning process 406 is disposed between the first supply process 402 and the bonding process 404, and before the bonding of the surface to be bonded to the adhesive on the organic EL element 401a of the sealing member 402a is bonded. Done. It is preferable to dispose a charge removing means (not shown) before or in the cleaning process 406. In particular, a non-contact type charge removing means (not shown) is more preferable to avoid generation of dust due to contact, Examples thereof include a corona discharge ionizer, a soft X-ray ionizer, and an ultraviolet irradiation ionizer.

  The cleaning process 406 includes a cleaning device 406b. As the cleaning device 406b, a dry cleaning method is preferable, and examples thereof include gas spraying, ultrasonic gas spraying, a combined gas spraying and suction method, and a combined ultrasonic gas spraying and suction method. The cleaning device 406b moves up and down a pressure plate (not shown) connected to a moving shaft 406b3 for stably performing dry cleaning of the sealing member 402a placed on the mounting table 409, and a pressure plate (not shown). It has a drive source 406b3 connected to a moving shaft 406b3 that moves in a direction (arrow K direction in the figure), a gas supply pipe 406b1, and a gas exhaust pipe 406b2. In the cleaning device 406b, cleaning is performed by blowing gas from the hollow portion of the mounting table 409 to the bonding surface of the sealing member 402a.

  The cleaning condition of the sealing member is the same as that of the cleaning device 306a shown in FIG. After washing in the washing step 406, the plate is moved along the guide rail 408 for movement by the moving means (not shown) to the bonding step 404 while being placed on the placing table 409.

The bonding step 404 includes a supply robot 404a, a bonding device 404b, and a curing processing device 404c. The supply robot 404a has the same mechanism and function as the supply robot 304a shown in FIG. In the bonding step 404, the sealing member 402a mounted on the mounting table 409 is superimposed on the adhesive surface 401a1 of the organic EL element 401a mounted on the mounting table 407 by the supply robot 404a. Then, the adhesion | attachment sealing of the organic EL element 401a by the sealing member 402a is complete | finished by crimping | bonding with the bonding apparatus 404b and processing with the hardening processing apparatus 404c, and an organic EL panel is manufactured. After the close sealing is completed, it is recovered in the recovery step 405. Incidentally, the surface pressure at the time of bonding by the bonding apparatus 404b, the flexible sealing member bonded condensable, damage or the like of the organic EL element is ^{considered, 0.5 × 10 4 Pa~9.8 × 10} 4 Pa is preferred. It is preferable to perform bonding by the bonding apparatus 304b in a reduced pressure environment of 1 Pa to 30 kPa in consideration of air bubbles.

  The curing processing device 404c can be changed according to the type of adhesive used. For example, when the adhesive is a thermosetting type, it becomes a curing processing apparatus having a heating device, and when it is an ultraviolet curing type, it becomes a curing processing apparatus having an ultraviolet irradiation device. Depending on the curing time and tact of the selected adhesive, the curing processing device 404c can be used as a temporary curing device and a main curing device. In addition, although the case where the bonding apparatus 404b and the hardening processing apparatus 404c are isolate | separated is shown in this figure, it is also possible to give the function of the hardening processing apparatus 404c to the bonding apparatus 404b. From the viewpoint of reducing the lifetime due to the deterioration of the organic EL element, it is important that the water concentration and the oxygen concentration are low until the above-described curing processing by the curing processing apparatus 404c. It is preferable to carry out below.

The manufacturing apparatus shown in FIGS. 5 and 6 is used, and a stress relaxation layer having an adhesive interface lower than the adhesive force between the second electrode and the organic electroluminescence layer is provided on the second electrode, as shown in FIGS. The following effects can be obtained by using a manufacturing apparatus and tightly sealing with a sealing member via an adhesive.
1) Propagation of residual stress due to curing shrinkage of the adhesive is suppressed by interfacial peeling of the relaxation layer, and damage to the light emitting element is reduced.
2) Propagation of the bonding pressure stress of the sealing member is suppressed by interfacial peeling of the relaxation layer, and damage to the light emitting element is reduced.
3) Damage to the light-emitting element can be suppressed without installing a new functional layer such as an adhesive layer, and the process can be simplified and miniaturized.
4) Since the relaxation layer is made of the same material as the organic EL layer, it is not necessary to prepare a new material as the relaxation layer, and it is not necessary to add a film forming apparatus. I can plan.
5) Production efficiency is improved.

  Hereinafter, the materials forming the substrate, the gas barrier layer, the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, the sealing layer and the like constituting the organic EL panel according to the present invention will be described.

  Examples of the substrate according to the present invention include a single wafer substrate and a strip-shaped flexible substrate. Examples of the single-wafer substrate include a transparent glass plate, a metal sheet, and a sheet-like transparent resin film. The same glass as the sealing member can be used as the transparent glass plate. As the metal sheet, the same metal sheet as the sealing member can be used. Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones, poly Cycloolefin resins such as ether imide, polyether ketone imide, polyamide, fluororesin, nylon, polymethyl methacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Apel (trade name, manufactured by Mitsui Chemicals) Can be mentioned. A transparent resin film is mentioned as a strip | belt-shaped flexible board | substrate, The same resin film as a single wafer board | substrate can be used.

When a transparent resin film is used as the substrate, a gas barrier film is preferably formed on the surface of the resin film as necessary. Examples of the gas barrier film include an inorganic film, an organic film, or a hybrid film of both. As a characteristic of the gas barrier film, the water vapor permeability is preferably 0.01 g / m ² · day · atm or less. Furthermore, a high barrier film having an oxygen permeability of 10 ⁻³ ml / m ² / day or less and a water vapor permeability of 10 ⁻⁵ g / m ² / day or less is preferable.

  As a material for forming the gas barrier film, any material may be used as long as it has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. 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 gas barrier film is not particularly limited. For example, the vacuum deposition method, the sputtering method, the reactive sputtering method, the molecular beam epitaxy method, the cluster ion beam method, the ion plating method, the plasma polymerization method, the atmospheric pressure plasma weighting. A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

As the first electrode, 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 an electrode substance 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) capable of forming a transparent conductive film may be used. For the anode, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when the pattern accuracy is not required (about 100 μm or more) ), A pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered. When light emission is extracted from the anode, the transmittance is desirably greater than 10%, and the sheet resistance as the 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.

  A hole injection layer (anode buffer layer) may be present between the first electrode 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”. Examples of the material used for the anode buffer layer (hole injection layer) include materials described in JP-A No. 2000-160328.

  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.

  Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. This hole transport layer may have a single layer structure composed of one or more of the above materials. A hole transport layer having a high p property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, JP-A-2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like. It is preferable to use such a hole transport layer having a high p property because an organic EL element with lower power consumption can be produced.

  According to the present invention, 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 light emitting layer according to 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, 4,4′-bis (2,2-diphenylvinyl) biphenyl). Specific examples of the dopant of the material are 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, in which light emission from the phosphorescent compound is obtained by moving to the phosphorescent compound, and the other is that the phosphorescent compound becomes a carrier trap, and recombination of the carriers on the phosphorescent compound occurs 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 according to 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 a luminance meter 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 ° C. viewing angle is measured by the above method. It is in the region of Y = 0.33 ± 0.07.

  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). The details of the electron injection layer (cathode buffer layer) are also described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. Metal buffer layer typified by lithium, alkali metal compound buffer layer typified by lithium fluoride, alkaline earth metal compound buffer layer typified by magnesium fluoride, 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.

As the second electrode, a material having a work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material 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, Suitable are a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum and the like. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The sheet resistance as the 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. 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.

  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.

  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 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).

  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. The introduced diffraction grating desirably 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 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 device according to the present invention can be processed to provide, for example, a structure on a microlens array on the light extraction side of the substrate in order to efficiently extract the light generated in the light emitting layer, or so-called collection. By combining with the light sheet, 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.

When using a flexible sealing member for the sealing member concerning this invention, the flexible sealing member of the multilayer structure which has a resin layer and a gas barrier layer is preferable. As the characteristics of the gas barrier layer, the water vapor transmission rate is 0.01 g / m ² · in consideration of crystallization of the organic layer, generation of dark spots due to peeling of the second electrode, and extension of the lifetime of the organic EL element. It is preferably not more than day. The water vapor transmission rate is a value measured mainly by the MOCON method by a method based on the JIS K7129B method (1992).

The oxygen permeability is 0.01 ml / m ² · day · atm or less in consideration of generation of dark spots due to crystallization of the organic layer, peeling of the second electrode, etc., and extension of the lifetime of the organic EL element. It is preferable. The oxygen permeability is a value measured mainly by the MOCON method by a method based on JIS K7126B method (1987).

  The thickness of the flexible sealing member to be used is preferably 10 to 300 μm in consideration of handleability during production, tensile strength, stress cracking resistance of the gas barrier layer, and the like. Thickness shows the average value which measured 10 each in the vertical direction and the width direction using the micrometer.

  The amount of moisture measured according to ASTM D570 when sealing the flexible sealing member is the generation of dark spots due to crystallization of the organic layer due to moisture brought in by the flexible sealing member, peeling of the second electrode, etc. In consideration of extending the life of the organic EL element and the like, 1.0% or less is preferable.

  The resin base material 108a constituting the flexible sealing member according to the present invention is not particularly limited. For example, ethylene tetrafluoroethyl copolymer (ETFE), high density polyethylene (HDPE), stretched polypropylene (0PP) , Polystyrene (PS), polymethyl methacrylate (PMMA), stretched nylon (ONy), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polyimide, polyether styrene (PES), etc. for general packaging The thermoplastic resin film material used for the film can be used. As these thermoplastic resin films, a multilayer film produced by coextrusion with a different film, a multilayer film produced by bonding with different stretching angles, etc. can be used as required. Further, it is naturally possible to combine the density and molecular weight distribution of the film used to obtain the required physical properties.

Examples of the moisture-proof layer include inorganic vapor-deposited films and metal foils. 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) Inorganic films as described in (1). For example, In, Sn, Pb, Au , Cu, Ag, Al, Ti, a metal such as _{Ni, MgO, SiO, SiO 2,} Al 2 O 3, GeO, NiO, CaO, BaO, Fe 2 O 3, Y 2 O ₃ , TiO ₂ , Cr ₂ O ₃ , Si _x O _y (x = 1, y = 1.5 to 2.0), Ta ₂ O ₃ , ZrN, SiC, TiC, PSG, Si ₃ N ₄ , SiN Single crystal Si, amorphous Si, W, or the like is used.

  Moreover, as a 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, but aluminum is preferable in terms of workability and cost. The film thickness is about 1 to 100 μm, preferably about 10 to 50 μm.

  The thickness of the glass plate to be used is preferably 0.1 mm to 2.0 mm in consideration of handling at the time of production, thinning of the panel, and the like. Thickness shows the average value which measured 10 each in the vertical direction and the width direction using the micrometer. The glass is not particularly limited, and examples thereof include silicate glass, alkali silicate glass, lead alkali glass, soda lime glass, potassium lime glass, barium glass, borosilicate glass, and phosphate glass.

  The thickness of the metal sheet to be used is preferably 20 μm to 2 mm in consideration of handling at the time of manufacture and panel thinning. Thickness shows the average value which measured 10 each in the vertical direction and the width direction using the micrometer. There is no limitation in particular as a metal, For example, metal materials, such as aluminum, copper, and nickel, alloy materials, such as stainless steel and an aluminum alloy, etc. are mentioned.

  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
<Production of organic EL element>
By using the manufacturing apparatus shown in FIG. 5, the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, the second electrode, and the stress relaxation layer are formed in this order on the substrate. An organic EL element having a size of 2 mm × 2 mm and a total of 70 dots (light emitting region) of 7 dots × 10 dots was prepared by the method described below. The production apparatus shown in FIG. 5 was carried out without using the gas permeation preventive layer forming vapor deposition apparatus and the second layer stress relaxation layer forming vapor deposition apparatus.

(Preparation of substrate)
A soda-lime glass having a thickness of 1.1 mm, a width of 40 mm, and a length of 60 mm was prepared as a substrate. In addition, the surface of the soda-lime glass used was a silica-coated glass for protection from acid and alkali.

(Formation of the first electrode)
The prepared glass substrate was cleaned by irradiation at a distance of 12 mm with an irradiation intensity of 15 mW / cm ² using a low-pressure mercury lamp having a wavelength of 184.2 nm. Thereafter, using a vapor deposition apparatus, indium tin oxide (ITO) is used under a vacuum of 5 × 10 ⁻⁴ Pa, and the deposited film formation region (first electrode formation region) of the prepared glass substrate A 1-electrode forming vapor deposition apparatus was used to form 7 rows of patterned first electrodes having a width of 2 mm, a length of 58 mm, a spacing of 2 mm, a thickness of 150 nm.

(Formation of hole transport layer)
A glass substrate on which the first electrode is formed is used, and N is used as a hole transport layer forming material on the first electrode except for an end portion for forming an external extraction electrode of the first electrode formed on the glass substrate. , N′-diphenyl-N, N′-m-tolyl 4,4′-diamino-1,1′-biphenyl (hereinafter referred to as TPD) and hole transport under a vacuum of 5 × 10 ⁻⁴ Pa A hole transport layer was formed by vapor deposition (vapor deposition) using a layer forming vapor deposition apparatus. The thickness of the hole transport layer was 50 nm.

(Formation of light emitting layer)
Using a glass substrate on which a hole transport layer is formed, using Alq ₃ as a light emitting layer forming material on the hole transport layer, and forming a light emitting layer by vapor deposition under a vacuum of 5 × 10 ⁻⁴ Pa The light emitting layer was formed by vapor deposition with an apparatus. The thickness of the light emitting layer was 50 nm.

(Formation of electron injection layer)
Using a glass substrate on which a light emitting layer is formed, using LiF as a material for forming an electron injection layer in a region where a hole transport layer including the light emitting layer is formed, under a vacuum of 5 × 10 ⁻⁴ Pa LiF was vapor-deposited with an electron injection layer forming vapor deposition apparatus to form an electron injection layer. The thickness of the electron injection layer was 0.5 nm.

(Formation of second electrode)
Using a glass substrate on which an electron injection layer is formed, aluminum is used for the second electrode on the electron injection layer, and deposition is performed by a second electrode formation vapor deposition apparatus under a vacuum of 5 × 10 ⁻⁴ Pa. did. The formed second electrode had a width of 2 mm, a length of 38 mm, an interval of 2 mm, a thickness of 150 nm, and a 10-row pattern.

(Formation of stress relaxation layer)
Using a glass substrate having a second electrode formed, using the first layer stress relieving layer formed vapor deposition apparatus shown in FIG. 5 the stress relieving layer at such conditions are shown in Table 1, 5 × 10 ^-4 An organic EL element was produced under vacuum of Pa. 1-1 to 1-10.

(Adhesion test)
An organic EL element No. having a stress relaxation layer formed thereon. Table 1-1 shows the results of testing the adhesive strength (peeling ratio of the second electrode) for 1-1 to 1-10. The adhesive strength test was conducted by the following test method.

Adhesive strength (peeling rate of second electrode) test method Adhesive tape (Sumitomo 3M Scotch Mending Tape) is bonded to the surface of the organic EL element (stress relaxation layer) at a pressure of 0.1 MPa for 3 minutes. After the alignment, the adhesive tape was peeled from the end of the adhesive tape 90 ° above the organic EL element surface, and the peeled state of the second electrode on the organic EL element surface was visually observed using a loupe (magnification 8 times). . Incidentally observation point is observed for any points 4 that corresponds to the light-emitting portion of the 2 × 2 mm (emission area total 4 mm ^2), and calculating the ratio of the peeled-off area of the second electrode to the emission area.

(Preparation of flexible sealing member)
A flexible sealing member having a configuration of PET 120 μm / SiO 30 nm / SiN 100 nm was prepared. The water vapor permeability of the prepared flexible sealing member measured by the MOCON method mainly in accordance with JIS K7129B 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 0.01 ml / m ² · day · atm.

<Adhesive sealing of organic EL element by flexible sealing member>
(Arrangement of adhesive on flexible sealing member)
Using the manufacturing process shown in FIG. 7, an ultraviolet curing liquid sealant (manufactured by ThreeBond 3124C, manufactured by Three Bond Co., Ltd.) is used, and the bonding surface side of the prepared flexible sealing member with the organic EL element is shown in FIG. After cleaning with the cleaning device in the first supply step of the manufacturing apparatus shown in FIG. 2, the surface was cleaned with a screen printing method with an adhesive placement device at a thickness of 50 μm. The flexible sealing member was cleaned under the conditions of a gas blowing rate of 5.5 m ³ / min, a nitrogen gas blowing rate of 100 m / sec, and a time of 3 minutes.

<Bonding with organic EL elements>
In the bonding process of the manufacturing apparatus shown in FIG. 1-1 to 1-10 and the prepared flexible sealing member are bonded together and pressure-bonded with a pressing force of 0.1 MPa under a reduced pressure environment of 1 × 10 ⁻² Pa, from the side of the flexible sealing member An organic EL panel that was cured and sealed by irradiation with ultraviolet light having a main wavelength of 365 nm (90 m at 100 mW / cm ² ) was prepared. 101-110.
(Evaluation)
Each prepared sample No. Table 2 shows the results of testing the occurrence ratios of dark spots (spot-like non-light emitting portions) by 101 to 110 by the test method shown below and evaluating according to the evaluation rank shown below.

Method for testing the rate of occurrence of dark spots (spot-like non-light emitting parts) Using a constant voltage power supply, DC 5 V is applied to one dot of an organic EL element, and the presence or absence of dark spots is visually observed using a loupe (magnification 8 times). Observed. Measurement was performed for all 70 dots (light emitting area), and the dark spot generation ratio was calculated from the number of dots where dark spots were generated.

Evaluation rank of dark spot generation rate A: Occurrence rate 0% (no dark spots are generated)
○: Occurrence rate 1% or more and less than 5% △: Occurrence rate 5% or more and less than 10% ×: Occurrence rate 10% or more

  Sample No. No. 109 showed a good result in the evaluation rank of the dark spot generation ratio, but production efficiency tends to be low because a large amount of material is required for film formation (deposition material efficiency tends to decrease). The effectiveness of the present invention was confirmed.

Example 2
<Production of organic EL element>
With the manufacturing apparatus shown in FIG. 5, the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, the second electrode, the gas permeation prevention layer, and the stress relaxation layer were formed in this order on the substrate. An organic EL element having a size of one dot of 2 mm × 2 mm and a total of 70 dots (light emitting region) of 7 dots × 10 dots was prepared by the method described below. The production apparatus shown in FIG. 5 was carried out without using the second layer stress relaxation layer forming vapor deposition apparatus.

(Formation of gas permeation prevention layer)
The manufacturing apparatus shown in FIG. 5 uses the same substrate as in Example 1, and the same materials and conditions as in Example 1 are used to form the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, and the second electrode. After the formation, SiO ₂ was used as a material for forming a gas permeation preventive layer, and deposition was performed with a gas permeation preventive layer forming vapor deposition apparatus under a vacuum of 5 × 10 ⁻⁴ Pa. The thickness of the formed gas permeation prevention layer was 30 nm.

(Formation of stress relaxation layer)
Using a glass substrate on which a gas permeation preventive layer is formed, using a first layer stress relaxation layer forming vapor deposition apparatus shown in FIG. 5 as a stress relaxation layer under the conditions shown in Table 3, 5 × 10 ^-4 Pa was formed under vacuum to produce an organic EL device. 2-1 to 2-10.

(Adhesion test)
An organic EL element No. having a stress relaxation layer formed thereon. The results of testing the adhesive strength (peeling ratio of the second electrode) for 2-1 to 2-10 are shown in Table 3. The adhesive strength test was performed by the same test method as in Example 1.

<Adhesive sealing of organic EL element by flexible sealing member>
After using the same flexible sealing member as in Example 1 and arranging the same adhesive as in Example 1 on the flexible sealing member under the same conditions, each organic EL element prepared in the same conditions as in Example 1 was prepared. No. 2-1 to 2-10 were bonded, cured, and sealed and sealed to produce an organic EL panel. 201-210.
(Evaluation)
Each prepared sample No. Table 4 shows the results of the evaluation of the occurrence ratio of dark spots (spot-shaped non-light emitting portions) in 201 to 210 by the same test method as in Example 1 and according to the same evaluation rank as in Example 1.

  Sample No. 209 showed good results in the evaluation rank of the dark spot generation ratio, but production efficiency tends to be low because a large amount of material is required for film formation (deposition material efficiency tends to decrease). The effectiveness of the present invention was confirmed.

Example 3
<Production of organic EL element>
With the manufacturing apparatus shown in FIG. 5, the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, the second electrode, the first stress relaxation layer, and the second stress relaxation layer are arranged on the substrate in this order. The size of one dot formed in (2) was 2 mm × 2 mm, and an organic EL element composed of 7 dots × 10 dots and a total of 70 dots (light emitting area) was prepared by the method described below. The production apparatus shown in FIG. 5 was carried out without using a gas permeation prevention layer forming vapor deposition apparatus.

(Formation of first stress relaxation layer)
The manufacturing apparatus shown in FIG. 5 uses the same substrate as in Example 1, and the same materials and conditions as in Example 1 are used to form the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, and the second electrode. After the formation, TPD was used as the first stress relaxation layer forming material, and deposition was performed with a first stress relaxation layer forming vapor deposition apparatus under a vacuum of 5 × 10 ⁻⁴ Pa. The thickness of the formed first stress relaxation layer was 10 nm.

(Formation of second stress relaxation layer)
Using a glass substrate on which the first stress relaxation layer is formed, using the second layer stress relaxation layer forming vapor deposition apparatus shown in FIG. 5 as the stress relaxation layer under the conditions shown in Table 5, 5 × An organic EL element was produced under vacuum of 10 ⁻⁴ Pa, 3-1 to 3-9.
(Adhesion test)
An organic EL element No. having a stress relaxation layer formed thereon. Table 5 shows the results of testing the adhesive strength (peeling ratio of the second electrode) for 3-1 to 3-9. The adhesive strength test was performed by the same test method as in Example 1.

<Adhesive sealing of organic EL element by flexible sealing member>
After using the same flexible sealing member as in Example 1 and arranging the same adhesive as in Example 1 on the flexible sealing member under the same conditions, each organic EL element prepared in the same conditions as in Example 1 was prepared. No. The organic EL panel which was bonded with 3-1 to 3-9, cured, and closely sealed was prepared. 301 to 309.
(Evaluation)
Each prepared sample No. Table 6 shows the results of the evaluation of the occurrence ratio of dark spots (spot-shaped non-light-emitting portions) 301 to 309 by the same test method as in Example 1 and according to the same evaluation rank as in Example 1.

  Sample No. Although 308 showed good results in the evaluation rank of the dark spot generation ratio, production efficiency tends to be low because many materials are required for film formation (the deposition material efficiency tends to decrease). The effectiveness of the present invention was confirmed.

Example 4
<Production of organic EL element>
With the manufacturing apparatus shown in FIG. 5, the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, the second electrode, the first stress relaxation layer, the gas permeation prevention layer, and the second stress relaxation are formed on the substrate. An organic EL element was prepared by the method described below, in which the size of each dot formed in this order was 2 mm × 2 mm, and was composed of 70 dots (light emitting area) in total of 7 dots × 10 dots. Note that the gas permeation preventive layer forming vapor deposition apparatus is arranged between the first stress relaxation layer forming vapor deposition apparatus and the second stress relaxation layer forming vapor deposition apparatus from the manufacturing apparatus shown in FIG. went.

(Formation of first stress relaxation layer)
The manufacturing apparatus shown in FIG. 5 uses the same substrate as in Example 1, and the same materials and conditions as in Example 1 are used to form the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, and the second electrode. After the formation, TPD was used as the first stress relaxation layer forming material, and deposition was performed with a first stress relaxation layer forming vapor deposition apparatus under a vacuum of 5 × 10 ⁻⁴ Pa. The thickness of the formed first stress relaxation layer was 10 nm.

(Formation of gas permeation prevention layer)
Using a glass substrate on which the first stress relaxation layer has been formed, using SiO ₂ as a gas permeation prevention layer forming material on the first stress relaxation layer, gas permeation under a vacuum of 5 × 10 ⁻⁴ Pa Deposited by a vapor deposition apparatus for forming a prevention layer. The thickness of the formed gas permeation prevention layer was 30 nm.

(Formation of second stress relaxation layer)
Using a glass substrate on which a gas permeation preventive layer is formed, using a first layer stress relaxation layer forming vapor deposition apparatus shown in FIG. 5 as a stress relaxation layer under the conditions shown in Table 7, 5 × 10 ^-4 Pa was formed under vacuum to produce an organic EL device. 4-1 to 4-9.

(Adhesion test)
An organic EL element No. having a stress relaxation layer formed thereon. Table 8 shows the results of testing the adhesive strength (peeling ratio of the second electrode) for 4-1 to 4-9. The adhesive strength test was performed by the same test method as in Example 1.

<Adhesive sealing of organic EL element by flexible sealing member>
After using the same flexible sealing member as in Example 1 and arranging the same adhesive as in Example 1 on the flexible sealing member under the same conditions, each organic EL element prepared in the same conditions as in Example 1 was prepared. No. 4-1 to 4-9 were bonded, cured, and sealed and sealed to produce an organic EL panel. 401-409.
(Evaluation)
Each prepared sample No. Table 8 shows the results of evaluation of the occurrence ratio of dark spots (spot-like non-light emitting portions) in 401 to 409 by the same test method as in Example 1 and evaluation according to the same evaluation rank as in Example 1.

  Sample No. 408 showed a good result in the evaluation rank of the dark spot generation ratio, but it requires a lot of materials for film formation (deposition material efficiency tends to decrease), so that production efficiency tends to be low. The effectiveness of the present invention was confirmed.

It is a schematic sectional drawing which shows an example of the laminated constitution of an organic EL element. It is a partial expansion schematic sectional drawing of FIG. It is an expansion schematic sectional drawing in case the stress relaxation layer shown by Fig.2 (a) is comprised from the multilayer. FIG. 3 is an enlarged schematic cross-sectional view of a portion indicated by T in FIG. 1 when the stress relaxation layer shown in FIG. It is a schematic diagram of the manufacturing method of the organic EL element which uses a single substrate. It is the schematic of the 1st layer stress relaxation layer formation vapor deposition apparatus shown by FIG. It is a schematic diagram of the manufacturing process of the organic EL element tightly sealed by the sealing member. It is a schematic diagram of the other manufacturing process of the organic EL element tightly sealed by the sealing member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic electroluminescent panel 101 Board | substrate 102 Organic electroluminescent layer 102a 1st electrode 102b Hole transport layer (hole injection layer)
102b Hole transport layer (hole injection layer)
102c Organic compound layer (light emitting layer)
102d Electron injection layer 103 Second electrode 104 Stress relaxation layer 104a to 104d, 104g to 104s Adhesive interface 104e First layer 104f Second layer 105 Adhesive layer 106 Sealing member 107 Gas permeation prevention layer 2 Manufacturing apparatus 203 First electrode formation Vapor deposition apparatus 204 Hole transport layer formation vapor deposition apparatus 205 Light emitting layer formation vapor deposition apparatus 206 Electron injection layer formation vapor deposition apparatus 207 Second electrode formation vapor deposition apparatus 208 Gas permeation prevention layer formation vapor deposition apparatus 209a First layer stress relaxation layer forming vapor deposition apparatus 209b Second layer stress relaxation layer forming vapor deposition apparatus 3, 4 Manufacturing process 301a, 402a Sealing member 302a, 401a Organic EL element 303 Arrangement process 304 Bonding process 306, 406 Cleaning process 308 Guide rail D Raw material evaporation means D1 Raw material container

Claims (20)

An organic electroluminescent element having a first electrode on the substrate, an organic electroluminescent layer having at least one organic compound layer including a light emitting layer, and a second electrode in this order, on the second electrode and In the method for producing an organic electroluminescence panel having a close sealing structure in which the peripheral surface is closely sealed with a sealing member via an adhesive layer,
Forming a stress relaxation layer having an adhesive interface between the second electrode and the adhesive layer, the adhesive force between adjacent layers being lower than the adhesive force between the second electrode and the organic electroluminescent layer; A manufacturing method of an organic electroluminescence panel characterized by the above. 2. The method of manufacturing an organic electroluminescence panel according to claim 1, wherein the stress relaxation layer is composed of at least two layers. 3. The organic electroluminescence panel according to claim 1, wherein an adhesion interface of at least one layer of the stress relaxation layer has an adhesion interface lower than an adhesion force between the second electrode and the organic electroluminescence layer. Method. The method of manufacturing an organic electroluminescence panel according to any one of claims 1 to 3, wherein the stress relaxation layer has a thickness of 1 nm or more and 10 µm or less. The method for producing an organic electroluminescence panel according to any one of claims 1 to 4, wherein at least one of the stress relaxation layers is any one of organic compounds constituting the organic electroluminescence layer. . The gas permeation preventive layer having gas permeation preventive property is provided on any of the stress relieving layer and the stress relieving layer on the second electrode. The manufacturing method of the organic electroluminescent panel of description. The organic electroluminescence according to claim 6, wherein the gas permeation preventive layer has an adhesion interface whose adhesion force at the adhesion interface with the stress relaxation layer is lower than the adhesion force between the second electrode and the organic electroluminescence layer. Panel manufacturing method. The substrate and / or the sealing member is a flexible sealing member having a resin base material and a gas barrier layer. Manufacturing method of organic electroluminescence panel. The method for manufacturing an organic electroluminescence panel according to any one of claims 1 to 7, wherein the substrate and / or the sealing member is a glass plate. The method for manufacturing an organic electroluminescence panel according to claim 1, wherein the substrate and / or the sealing member is a metal sheet. An organic electroluminescent element having a first electrode on the substrate, an organic electroluminescent layer having at least one organic compound layer including a light emitting layer, and a second electrode in this order, on the second electrode and In the organic electroluminescence panel having a close sealing structure in which the peripheral surface is closely sealed with a sealing member via an adhesive layer,
Having a stress relaxation layer between the second electrode and the adhesive layer;
The organic electroluminescence panel according to claim 1, wherein the stress relaxation layer has an adhesion interface in which an adhesion force between adjacent layers is lower than an adhesion force between the second electrode and the organic electroluminescence layer. The organic electroluminescence panel according to claim 11, wherein the stress relaxation layer includes at least two layers. The organic electroluminescence panel according to claim 11 or 12, wherein an adhesion interface of at least one layer of the stress relaxation layer has an adhesion interface lower than an adhesion force between the second electrode and the organic electroluminescence layer. 14. The organic electroluminescence panel according to claim 11, wherein the stress relaxation layer has a thickness of 1 nm or more and 10 μm or less. The organic electroluminescence panel according to claim 11, wherein at least one of the stress relaxation layers is an organic compound constituting an organic compound layer of the organic electroluminescence layer. The gas permeation preventive layer having gas permeation preventive properties is provided on any of the stress relieving layer and the stress relieving layer on the second electrode. The organic electroluminescence panel described. The organic electroluminescence according to claim 16, wherein the gas permeation preventive layer has an adhesion interface whose adhesion force at the adhesion interface with the stress relaxation layer is lower than the adhesion force between the second electrode and the organic electroluminescence layer. panel. 18. The substrate according to claim 11, wherein the substrate and / or the sealing member is a flexible sealing member having a resin base material and a gas barrier layer. Organic electroluminescence panel. The organic electroluminescence panel according to any one of claims 11 to 17, wherein the substrate and / or the sealing member is a glass plate. The organic electroluminescence panel according to claim 11, wherein the substrate and / or the sealing member is a metal sheet.

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