JP2008077854A - Organic electroluminescent panel and method of manufacturing organic electroluminescent panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL panel in which invasion of gas from the end face exposed to external air of an adhesive layer is prevented without installing a new process, without using a new material, or without requiring complicated management, and a manufacturing method of the organic EL panel. <P>SOLUTION: In the organic EL having a structure of sealing the organic EL element having at least an anode layer containing a first electrode, an organic compound layer containing a light emitting layer, and a cathode layer containing a second electrode on a substrate by a sealing member to seal at least a surface of the organic EL element via the adhesive layer, this is the organic EL panel in which the sealing member is provided with a convex part facing a side of the adhesive layer on the end side of a joint surface (rear face) with the adhesive layer and in which the length of the convex part is 10% to 20% to the thickness of the adhesive layer by making the joint surface with the adhesive of the end side a reference. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  In recent years, organic EL panels 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 has been underway. The organic EL panel includes an anode layer (cathode layer) including a first electrode (anode or cathode) formed on a substrate, and an organic compound layer (single layer portion or multilayer) containing an organic light emitting material laminated thereon. Part), that is, an organic electroluminescent element (hereinafter also referred to as an organic EL element) having a light emitting layer and a cathode layer (anode layer) including a second electrode (cathode or anode) laminated on the light emitting layer. It has a thin film type structure sealed with a sealing member that seals at least the surface of the organic EL element via a layer.

  When a voltage is applied to such an organic EL panel, 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, 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 is provided. The device can be easily made thin. 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.

  Usually, an organic EL panel has a first electrode (anode), a hole transport layer (hole injection layer), an organic compound layer (light emitting layer), an electron injection layer, and a second electrode (on the substrate). The organic EL element on which the cathode is formed is sealed with a sealing member via an adhesive layer, and the end portions of the first electrode (anode) and the second electrode (cathode) are on the substrate. It is drawn out as an extraction electrode. In the organic EL panel having such a configuration, an electron transport layer may be provided between the cathode, the organic compound layer (light emitting layer), and the electron injection layer. A gas barrier film may be provided between the anode and the substrate.

  In applying the organic EL panel as described above to a display device, stable light emission of the three primary colors of RGB is an indispensable condition. However, in an organic EL panel, a non-light emitting point called a dark spot is generated by long-time driving, and the growth of the dark spot is one of the causes for shortening the lifetime of the organic EL element. It is known that a dark spot is generally generated in a size that cannot be seen with the naked eye immediately after driving, and grows by continuous driving using this as a core. Further, it is known that dark spots are generated even in a storage state where driving is not performed and grows with time.

  There are various causes of the dark spot, but external factors include crystallization of the organic layer due to the penetration of moisture or oxygen into the organic EL element, peeling of the second electrode, and the like. As internal factors, short spots due to crystal growth of the metal constituting the second electrode, crystallization and deterioration of the organic layer due to heat generation due to light emission, and the like are considered as factors of dark spots.

  As countermeasures for preventing the occurrence of these dark spots, for example, JP-A-5-182759, JP-A-5-36475, and JP-A-2002-43055 disclose a metal or glass sealing can in a dry nitrogen atmosphere. A method for covering and sealing an organic EL element via an adhesive layer is described. Japanese Patent Application Laid-Open Nos. 2001-307871 and 2002-50470 describe a method of covering and sealing an organic EL element through an adhesive layer using a film having a high barrier property such as a metal foil. However, even when sealing with these metal or glass sealing cans or sealing using a highly barrier film such as metal foil, the end face of the adhesive layer is exposed and exposed to the outside air. Therefore, there is a problem that gas (moisture, oxygen, etc.) enters through the adhesive layer and deteriorates the organic EL element.

  As a method for preventing gas from entering from the end face of the adhesive layer, for example, a method of putting moisture-proof particles in the adhesive layer is known (for example, see Patent Document 1). However, in the method described in Patent Document 1, the amount of moisture-proof particles added to the adhesive layer is also added within a range where the adhesive strength of the adhesive layer does not decrease, so there is a limit in preventing gas intrusion. This is insufficient to maintain the performance of the EL element. Further, a new process is required to uniformly disperse the moisture-proof particles, and complicated management including management of the moisture-proof particles is required.

  A method of folding the sealing portion is known (for example, see Patent Document 2). However, in the method described in Patent Document 2, it is necessary for both the substrate and the sealing member to be flexible in order to fold, limiting the material to be used, and limiting the moisture resistance. There is a risk that the production of high-quality organic EL panels may be limited and the demand from the market cannot be met. Moreover, it must have a folding step, and there is a concern about cost increase accompanying complication including management of the folded portion.

  There is known a method of covering an end portion of an adhesive portion with a metal member (for example, see Patent Document 3). However, in the method described in Patent Document 3, a new sealing step when covering with a metal member, a cost increase associated with the use of a new material, etc., an organic EL element accompanying heating when covering with a metal member There is also concern about the impact on

In this situation, it is possible to prevent gas from entering from the end face exposed to the outside air of the adhesive layer without installing new processes, using new materials, or requiring complicated management. However, it is desired to develop an organic EL panel having a long lifetime and a method for manufacturing the organic EL panel.
JP-A-2005-79056 JP 2005-310908 A JP 2005-322580 A

  The present invention has been made in view of the above situation, and the object thereof is to install the outside air of the adhesive layer without using a new process, without using a new material, and without requiring complicated management. An organic EL panel in which gas intrusion from an end face exposed to the surface is prevented and a method for manufacturing the organic EL panel are provided.

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

  1. An organic electroluminescent device having an anode layer including at least a first electrode, an organic compound layer including a light-emitting layer, and a cathode layer including a second electrode on a substrate is disposed at least on the organic electroluminescence element via an adhesive layer. In the organic electroluminescence panel having a structure sealed with a sealing member that seals the surface of the luminescence element, the sealing member is formed on the edge of the bonding surface (back surface) with the adhesive layer. A convex portion facing toward the side, and the length of the convex portion is 10 with respect to the thickness of the adhesive layer on the basis of the joint surface (back surface) with the adhesive layer on the end side. An organic electroluminescence panel characterized in that the organic electroluminescence panel is in a range of% to 200%.

  2. 2. The organic electroluminescence panel according to 1, wherein the convex portion is provided in an amount of 10% or more with respect to a total length of an outer peripheral edge of the sealing member.

  3. At least the organic electroluminescence element having an anode layer including at least a first electrode, an organic compound layer including a light emitting layer, and a cathode layer including a second electrode on a substrate via an adhesive layer. In the method of manufacturing an organic electroluminescence panel having a structure sealed with a sealing member that seals the surface of the element, the sealing member is formed on the end surface of the bonding surface (back surface) with the adhesive layer. On the basis of the (back surface), a convex portion that is 10% to 200% with respect to the thickness of the adhesive layer is integrally provided, and the adhesive layer is used as the sealing member or the organic electroluminescence element. Then, the sealing member is disposed on the organic electroluminescence element and the convex portion is directed toward the substrate. Allowed method of producing an organic electroluminescent panel, characterized in that sealing the organic electroluminescence device.

  4). 4. The method for producing an organic electroluminescence panel according to 3, wherein the convex portion is provided at 10% or more with respect to the entire length of the outer peripheral edge of the sealing member.

  5. 5. The method for producing an organic electroluminescence panel according to 3 or 4, wherein the sealing member is produced by a cutting method.

  6). 6. The organic electroluminescence panel according to 5 above, wherein when the cutting method is push-cut cutting, cutting is performed by inserting a cutting blade from the surface (surface) opposite to the bonding surface with the adhesive layer of the sealing member. Method.

  7. When the cutting method is a punch and die method having an upper blade and a lower blade, a joining surface (back surface) where at least one of the upper and lower blades is joined to the adhesive layer of the sealing member; 6. The method for producing an organic electroluminescence panel as described in 5 above, wherein the organic electroluminescence panel is cut so as to be in contact.

  8). The cutting method is a punch and die method having an upper blade and a lower blade, and the clearance between the upper blade and the lower blade is 1% to 150% with respect to the thickness of the sealing member. 5. The method for producing an organic electroluminescence panel according to 5 above.

  9. The cutting method is a punch die method having an upper blade and a lower blade, and the clearance between the upper blade and the lower blade is 1% to 150% with respect to the thickness of the sealing member, 6. The organic electroluminescence panel according to 5 above, wherein cutting is performed such that at least one of the upper blade and the lower blade is in contact with a bonding surface (back surface) to be bonded to the adhesive layer of the sealing member. Manufacturing method.

  Organic EL panel and organic that prevent intrusion of gas from the end face exposed to the outside air of the adhesive layer without installing a new process, using a new material, without requiring complicated management An EL panel manufacturing method can be provided, and an organic EL panel having stable performance even after long-term use can be produced.

  Embodiments of the present invention will be described with reference to FIGS. 1 to 12, but the present invention is not limited thereto.

  FIG. 1 is a schematic view showing an example of the configuration of an organic EL panel. FIG. 1A is a schematic diagram showing an example of the configuration of an organic EL panel. FIG.1 (b) is a schematic sectional drawing in alignment with AA 'of Fig.1 (a). FIG.1 (c) is a schematic sectional drawing in alignment with BB 'of Fig.1 (a).

  In the figure, 1a represents an organic EL panel. The organic EL panel 1a includes an anode layer 102a including a first electrode 102a1, a hole transport layer (hole injection layer) 102b, an organic compound layer (light emitting layer) 102c, and an electron injection layer 102d on a substrate 101. An organic EL element 102 having a cathode layer 102e including a second electrode 102e1, a first extraction electrode 102a2 from the first electrode 102a1, and a second extraction electrode 102e2 from the second electrode 102e1, and an organic EL element 102 The structure is sealed by a sealing member 104 via an adhesive layer 103 provided on the periphery and surface of the substrate. The first extraction electrode 102a2 and the second extraction electrode 102e2 are in an exposed state. Reference numeral 104 c denotes an end side of the sealing member 104 on the side of the bonding surface (back surface) 104 b opposite to the surface (front surface) 104 a, and 104 d denotes an end side of the bonding surface (back surface) 104 b side to the adhesive layer 103. Reference numeral 104 e denotes an end face of the sealing member 104. Reference numeral 103 a denotes an exposed surface of the adhesive layer 103, which is formed around the organic EL element 102. The surface 103a is always exposed to the outside air, and the life of the organic EL element 102 is shortened by gas (water, air, etc.) entering from the surface 103a.

  FIG. 2 is a schematic view showing an example of another configuration of the organic EL panel. FIG. 2A is a schematic diagram illustrating an example of another configuration of the organic EL panel. FIG. 2B is a schematic cross-sectional view along CC ′ of FIG. FIG. 2C is a schematic cross-sectional view taken along the line DD ′ in FIG.

  In the figure, 1b represents an organic EL panel. Reference numeral 105 denotes a container-type sealing member having a convex cross-sectional shape. Reference numeral 106 denotes an adhesive layer for fixing the container-type sealing member 105. The organic EL panel 1b has a structure in which the organic EL element 102 is covered with a container-type sealing member 105 and fixed and sealed with an adhesive layer. The first extraction electrode 102a2 and the second extraction electrode 102e2 are in an exposed state. Reference numeral 105c denotes an outer peripheral edge on the surface 105a side of the sealing member 105, and 105d denotes an edge on the bonding surface (back surface) 105b side with the adhesive layer 106. Reference numeral 105 e denotes an end face of the sealing member 105. Reference numeral 106 a denotes an exposed surface of the adhesive layer 106, which is formed between the peripheral portion of the container-type sealing member 106 and the base material 101. The surface 106a is always exposed to the outside air, and the life of the organic EL element 102 is shortened by gas (water, air, etc.) entering from the surface 106a. Reference numeral 107 denotes a hygroscopic agent disposed in the space between the organic EL element 102 and the container-type sealing member 105. As the hygroscopic agent, a generally used sheet-like or powder-like hygroscopic agent can be used, but a chemical adsorbent that hardly releases the adsorbed moisture is preferable. For example, alkali metal oxides, alkaline earth metal oxides, and the like can be given. Moreover, when using a powdery moisture absorbent, it is preferable to fix using a film having moisture permeability or the like. Other reference numerals are the same as those in FIG.

  In the organic EL panel shown in FIGS. 1 and 2, a hole injection layer (not shown) may be provided between the anode layer 102 a including the first electrode 102 a 1 and the hole transport layer 103. Further, an electron transport layer (not shown) may be provided between the cathode layer 102e including the second electrode 102e1, the organic compound layer (light emitting layer) 104, and the electron injection layer 105. In the organic EL element 102, a gas barrier film (not shown) may be provided between the anode layer 102a including the first electrode 102a1 and the substrate 101.

  The present invention relates to an organic EL panel that prevents gas from entering from the exposed surface 103a of the adhesive layer 103 shown in FIG. 1 and the exposed surface 106a of the adhesive layer 106 shown in FIG. It is about.

FIG. 3 is an enlarged schematic view of a portion indicated by S in FIG.
In the figure, 104 f indicates a convex portion provided on the end side 104 d of the sealing member 104 facing the adhesive layer 103. The exposed surface 103a of the adhesive layer 103 is covered with the convex portion 104f, and has a function of preventing intrusion of gas (moisture, air, etc.) from the surface 103a.

  E indicates the length from the edge 104d on the side of the bonding surface (back surface) 104b to the adhesive layer 103 to the tip of the convex portion 104f. E ′ indicates the thickness of the adhesive layer 103 from the surface of the base material 101 to the bonding surface (back surface) 104b of the sealing member 104. The length E is 10% to 200% with respect to the thickness E ′ of the adhesive layer 103. Particularly preferably, it is 50% to 100%. When the length E is less than 10%, the area covering the exposed surface 103a of the adhesive layer 103 is reduced, and the effect of preventing the intrusion of gas (moisture, air, etc.) is lost. When the length E exceeds 200%, the area of the end face of the adhesive layer where the joint surface rises and is exposed is increased, and the effect of preventing the intrusion of gas (moisture, air, etc.) is lost.

  The protruding portion 104f allows gas (moisture, air, etc.) to enter the end 104d of the sealing member 104 from the exposed surface 103a of the adhesive layer 103 with respect to the entire length of the outer periphery of the sealing member 104. Considering the effect to prevent, it is preferable that 10% or more is provided. The convex portion 104f may be formed from any of the end side 104c, the end surface 104e, and the end side 104d of the sealing member 104 toward the adhesive layer 103 side.

  FIG. 4 is an enlarged schematic view of a portion indicated by T in FIG.

  In the figure, 105f denotes a convex portion provided on the end side 105d of the sealing member 105 toward the adhesive layer 106 side. The exposed surface 106a of the adhesive layer 106 is covered with the convex portion 105f, and has a function of preventing intrusion of gas (moisture, air, etc.) from the surface 106a.

  F indicates the length from the edge 105d on the side of the bonding surface (back surface) 105b to the adhesive layer 106 to the tip of the convex portion 105f. F ′ represents the thickness of the adhesive layer 106 from the surface of the substrate 101 to the bonding surface (back surface) 105 b of the sealing member 105. The length F is 10% to 200% with respect to the thickness F ′ of the adhesive layer 106. Particularly preferably, it is 50% to 100%. When the length F is less than 10%, the area covering the exposed surface 106a of the adhesive layer 106 is reduced, and the effect of preventing the intrusion of gas (moisture, air, etc.) is lost. When the length E exceeds 200%, the area of the end face of the adhesive layer where the joint surface rises and is exposed is increased, and the effect of preventing the intrusion of gas (moisture, air, etc.) is lost.

  The convex portion 105f allows gas (moisture, air, etc.) to enter the end side 105d of the sealing member 105 from the exposed surface 106a of the adhesive layer 106 with respect to the entire length of the outer peripheral side of the sealing member 105. Considering the effect to prevent, it is preferable that 10% or more is provided. The convex portion 105f may be formed from any one of the end side 105c, the end surface 1054e, and the end side 105d of the sealing member 105 toward the adhesive layer 106 side.

  Next, a method for manufacturing the organic EL panel shown in FIGS. 1 and 2 will be described. The following two methods are mentioned as a manufacturing method of the organic EL panel of the present invention. 1) A batch system in which sealing is performed by adhering and fixing a sealing member manufactured according to the size of the organic EL element to an organic EL element manufactured in an individual size. 2) A strip shape having a plurality of organic EL elements. A continuous method in which a band-shaped sealing member is bonded and fixed to the organic EL element and then cut individually. These manufacturing methods can be appropriately selected according to the state of the organic EL element to be used. The cutting method after the sealing member or the organic EL element is bonded and fixed with the sealing member is not particularly limited, and examples thereof include push cutting with a Thomson blade and an engraving blade, and punch cutting with a punch and die. Below, it attaches and demonstrates to the manufacturing method of the sealing member used when manufacturing an organic electroluminescent panel by a batch system.

  FIG. 5 is a schematic view of a punching and cutting apparatus using a punch and die. FIG. 5A is a schematic perspective view of a punching and cutting apparatus using a punch and die. FIG. 5B is a schematic cross-sectional view taken along the line II ′ of FIG.

  In the figure, 2 indicates a punching and cutting apparatus. The punching and cutting apparatus 2 includes an upper mold 202 provided with a punch (upper blade) 201 for punching a sealing member, and four upper molds 202 that can be operated in the vertical direction (arrow direction in the figure). It has a lower die 206 having a guide post 203 and a placement surface 205 on which a sealing member is placed and a die (lower blade) 204 is placed. Reference numeral 207 denotes a drive source for operating the upper mold 202 in the vertical direction (the arrow direction in the drawing) along the guide post 203, and 208 denotes a drive shaft. Reference numeral 209 denotes an attachment member for the punch (upper blade) 201 and is attached to the upper die 202. The number of punches (upper blades) 201 can be appropriately selected from the size of the organic EL element, the number of punches at a time, the size of the punching and cutting device 2, and the like. The dies (lower blades) 204 are also arranged according to the number of punches (upper blades) 201. This figure shows the case where the number of punches at one time is one.

  In order to fix the sealing member at the time of cutting, it is possible to provide suction holes on the mounting surface 205 and fix them by suction. It is also possible to provide a stripper (not shown) for suppressing the sealing member around the punch (upper blade) 201 and a knockout (not shown) for collecting the punched product from the die (lower blade) 204. . The punch of the punching and cutting apparatus shown in this figure can be used as a punching-type cutting apparatus by using a punching blade as a punch and a lower die attached with a die as a receiving part of the punching blade.

  FIG. 6 is an enlarged schematic view of a portion indicated by U in FIG.

  In the figure, J indicates a clearance (gap) between the upper blade 201 and the lower blade 204. The clearance J is preferably 1% to 150% with respect to the thickness of the sealing member to be cut in consideration of the length of the convex matter generated at the end of the joint surface with the adhesive layer.

  θ1 indicates the angle of the cutting edge of the punch (upper blade) 201, and the angle θ1 is 50 ° in consideration of the durability of the blade, the length of the convex object generated on the edge of the joint surface with the adhesive layer, and the like. ~ 90 ° is preferred. θ2 indicates the angle of the cutting edge of the die (lower blade) 204, and the angle θ2 is 50 ° in consideration of the durability of the blade, the length of the convex object generated on the edge of the joint surface with the adhesive layer, and the like. ~ 90 ° is preferred. The punch (upper blade) 201 may have a shear angle.

  FIG. 7 is a schematic view of a punching blade (engraving blade) used in place of the punch and lower die shown in FIG. FIG. 7A is a schematic perspective view of the punching blade. FIG. 7B is a schematic partial sectional view showing the relationship between the punching blade (engraving blade) and the receiving portion.

  In the figure, 3 indicates a punching blade. Reference numeral 302 denotes a jig for attaching the punching blade 3 to the upper mold 202. The punching blade 3 shown in this figure is composed of four linear punching blades 301a to 301d, and is attached to the upper die 202 so as to abut at right angles to each other.

  θ3 represents the angle of the cutting edge of the punching 3, and the angle θ3 is preferably 7 to 75 ° in consideration of the length of the convex matter generated at the edge of the joint surface with the adhesive layer. The shape of the blade may be single-edged or double-edged. As the blade material used for the punching blade, general materials such as SKH and SKD materials can be used. Reference numeral 303 denotes a cradle for the punching blade 3.

  FIG. 8 is a schematic view showing the relationship between the blade and the sealing member when the sealing member is cut with a cutting device. FIG. 8A is a schematic view showing the relationship between the punch and die blade and the sealing member when cutting with the punch and die of the punching and cutting apparatus shown in FIG. FIG. 8B is a schematic view showing the relationship between the punching blade and the sealing member when cutting with the punching blade shown in FIG.

  This will be described with reference to FIG. In the figure, 201a indicates the anti-mineral surface of the punch (upper blade) 201, and 201b indicates the miner surface of the punch (upper blade) 201. Reference numeral 204 a denotes an anti-mineral surface of the die (lower blade) 204, and 204 b denotes a minor surface of the die (lower blade) 204. As shown in this figure, when the sealing member 104 is cut by the punching and cutting apparatus shown in FIG. 5 using a punch (upper blade) 201 and a die (lower blade) 204, the sealing member 104 is punch (upper blade) 201. It is preferable to cut such that the mining surface 201b and the bonding surface 104b are in contact with each other. When cutting the sealing member 104, the cutting blade and the sealing member are in the relationship shown in this figure, and the clearance between the punch (upper blade) 201 and the die (lower blade) 204 is adjusted. Thus, the sealing member as shown in FIG. 9 can be cut.

  This will be described with reference to FIG. In the figure, 301b1 represents the anti-mineral surface of the punching blade 301b, and 301b2 represents the mining surface of the punching blade 301b. When cutting with the punching blade 301b shown in this drawing (the punching blade 3 shown in FIG. 7), it is preferable that the sealing member 104 is placed on the cradle 303 with the surface 104a on the upper side and cut. When cutting the sealing member 104, it becomes possible to cut the sealing member as shown in FIG. 9 by making the punching blade for cutting and the sealing member into a relationship as shown in this figure. .

  Of course, it is also possible to manufacture the organic EL panel by incorporating the cutting apparatus shown in FIGS. 5 to 7 into the continuous production method and individually cutting the sealing member after bonding and fixing to the organic EL element.

  FIG. 9 is a schematic view of a sealing member used for manufacturing the organic EL panel shown in FIG. Fig.9 (a) is a schematic diagram of the sealing member used in manufacturing the organic electroluminescent panel shown by FIG. FIG. 9B is an enlarged schematic cross-sectional view along the line GG ′ in FIG. This figure shows the sealing member cut by the cutting apparatus shown in FIG.

  The reference numerals in the figure are the same as those in FIG. This figure shows a state in which a convex member 104 f is provided on the end edge around the sealing member 104 by 10% or more with respect to the entire length around the sealing member 104. The sealing member 104 in the state shown in this figure can be manufactured by inserting and punching a sheet-like member from the surface opposite to the surface to be bonded to the adhesive layer by the punching and cutting method. The member may be a single sheet or a belt-like sheet, and can be selected as necessary.

  FIG. 10 is a schematic view of a container-type sealing member used for manufacturing the organic EL panel shown in FIG. Fig.10 (a) is a schematic diagram of the container type sealing member used in manufacturing the organic EL panel shown by FIG. FIG. 10B is an enlarged schematic cross-sectional view taken along line HH ′ of FIG. This figure shows the sealing member cut by the cutting apparatus shown in FIG.

  The reference numerals in the figure are the same as those in FIG. This figure shows a state in which a convex member 105 f is provided on the edge around the container-type sealing member 105 by 10% or more with respect to the entire length around the container-type sealing member 105. The container-type sealing member 105 in the state shown in the figure is formed into a concave container mold (or convex container mold) by once forming a sheet-like member, and then joined to the adhesive layer. It is possible to manufacture by inserting a cutting blade from the surface opposite to the surface and punching the periphery by a cutting method. Further, it can be manufactured by stamping simultaneously with molding. The member may be a single sheet or a belt-like sheet, and can be selected as necessary.

  FIG. 11 is a schematic flow chart for manufacturing the organic EL panel shown in FIG. A method for manufacturing the organic EL panel shown in FIG. 1 will be described with reference to FIG.

  In S1, the anode layer 102a (see FIG. 1) including the first electrode 102a1 on the substrate 101, the hole transport layer (hole injection layer) 102b (see FIG. 1), the organic compound layer (light emitting layer) ) 102c (see FIG. 1), an electron injection layer 102d (see FIG. 1), a cathode layer 102e including a second electrode 102e1, a first extraction electrode 102a2 from the first electrode 102a1, and a second electrode 102e1 The organic EL element 102 having the second take-out electrode 102e2 is prepared.

  In S2, tips of the first extraction electrode 102a2 and the second extraction electrode 102e2 are exposed on the cathode layer 102e including the second electrode 102e1 of the organic EL element 102 prepared in S1 and around the organic EL element 102. In this state, an adhesive is applied to form an adhesive layer 103. In addition, although this figure shows the case where the adhesive layer is provided on the organic EL element 102 side, the adhesive layer may be provided on the sealing member 104 side.

  In S3, the sealing member 104 manufactured by the punching and cutting apparatus shown in FIG. 5 and having the convex 104f on the short side of the outer periphery (see FIG. 9) is prepared.

  In S4, the organic EL panel shown in FIG. 1 is manufactured by superimposing the sealing member 104 prepared in S3 on the organic EL element 102 with the convex 104f facing the adhesive layer 103 side.

  FIG. 12 is a schematic flow diagram for manufacturing the organic EL panel shown in FIG. A method for manufacturing the organic EL panel shown in FIG. 2 will be described with reference to FIG.

  In S1, the anode layer 102a including the first electrode 102a1 on the substrate 101, the hole transport layer (hole injection layer) 102b (see FIG. 1), and the organic compound layer (light emitting layer) 102c (see FIG. 1). Reference), an electron injection layer 102d (see FIG. 1), a cathode layer 102e6 including a second electrode 102e1, a first extraction electrode 102a2 from the first electrode 102a1, and a second extraction from the second electrode 102e1. An organic EL element 102 having an electrode 102e2 is prepared.

  In S2, an adhesive is applied around the organic EL element 102 prepared in S1 with the tips of the first extraction electrode 102a2 and the second extraction electrode 102e2 exposed to form an adhesive layer 106. . In addition, although this figure shows the case where the adhesive layer is provided on the organic EL element 102 side, the adhesive layer may be provided on the sealing member 105 side.

  In S3, the container-type sealing member 105 manufactured by the punching and cutting method shown in FIG. 5 and having a convex 105f on the outer short side (see FIG. 10) is prepared.

  In S4, the convex object 105f of the container-type sealing member 105 prepared in S3 is directed toward the adhesive layer 106 and is superimposed on the organic EL element 102, whereby the organic EL panel shown in FIG. 2 is manufactured. The

By using the sealing member shown in FIGS. 9 and 10 produced by punching and cutting the sealing member with the cutting device shown in FIGS. 5 to 8, and manufacturing the organic EL panel according to the flow shown in FIGS. The following effects can be mentioned.
1. It is possible to manufacture an organic EL panel that covers the exposed surface of the adhesive layer using a conventional process without installing a new process. An excellent organic EL panel can be manufactured.
2. Since the exposed surface of the adhesive layer is covered with the convex portion, the intrusion of gas (moisture, oxygen, etc.) from the exposed surface can be reduced, and the life of the organic EL element can be extended. It was.

  The configuration of the organic EL panel of the present invention shown in FIG. 1 and FIG. 2 shows an example, but the following configuration can be given as a configuration of another typical organic EL panel.

(1) Substrate / Anode (first electrode) / Light emitting layer / Electron transport layer / Cathode (second electrode) / Adhesive layer / Sealing member (2) Substrate / Anode (first electrode) / Hole transport layer / Light emitting layer / hole blocking layer / electron transport layer / cathode (second electrode) / adhesive layer / sealing member (3) substrate / anode (first electrode) / hole transport layer (hole injection layer) / light emission Layer / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / cathode (second electrode) / adhesive layer / sealing member (4) substrate / anode (first electrode) / anode buffer layer ( Hole injection layer) / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer (electron injection layer) / cathode (second electrode) / adhesive layer / sealing member A state in which at least a first electrode layer, an organic compound layer including a light emitting layer, and a second electrode layer are sequentially stacked on a substrate is called an organic EL element, and is covered with a sealing layer. The covered state is called an organic EL panel.

  Next, the sealing member used for the structure of the organic EL panel shown in FIG. 1 will be described.

(Sealing member)
The base material of the sealing member used for the configuration of the organic EL panel shown in FIG. 1 is not particularly limited. For example, ethylene tetrafluoroethyl copolymer (ETFE), high-density polyethylene (HDPE), or oriented polypropylene (0PP) , Heat used in general packaging films such as polystyrene (PS), polymethyl methacrylate (PMMA), stretched nylon (ONy), polyethylene terephthalate (PET), polycarbonate (PC), polyimide, polyether styrene (PES) Plastic resin film material, glass, metal foil, etc. 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.

In the case of a thermoplastic resin film, it is necessary to form a barrier layer by vapor deposition or coating. Examples of the barrier layer include an inorganic vapor deposition film and a metal foil. As inorganic vapor deposition films, thin film handbooks p879-p901 (Japan Society for the Promotion of Science), vacuum technology handbooks p502-p509, p612, p810 (Nikkan Kogyo Shimbun), vacuum handbook revised editions p132-p134 (ULVAC Nippon Vacuum Technology 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 , single Crystalline Si, amorphous Si, W, etc. are 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. In order to facilitate handling during production, a film such as polyethylene terephthalate or nylon may be laminated in advance. When a resin film is used for the flexible sealing member, it is preferable to have a thermoplastic adhesive resin layer on the side in contact with the liquid sealing agent.

  Further, a protective layer may be provided on the barrier layer. The thickness of the protective layer is preferably 100 nm to 200 μm in consideration of stress cracking resistance, electrical insulation resistance of the barrier layer, adhesiveness (adhesive force, step following ability), etc. when used as a sealing agent layer. As the protective layer, a thermoplastic resin film having a JIS K 7210 standard melt flow rate of 5 to 20 g / 10 min is preferable, and a thermoplastic resin film of 6 to 15 g / 10 min or less is more preferably used. This is because if a resin with a melt flow rate of 5 (g / 10 min) or less is used, the gap formed by the steps of the extraction electrode of each electrode cannot be completely filled, and a resin of 20 (g / 10 min) or more cannot be filled. This is because if used, the tensile strength, stress cracking resistance, workability and the like are lowered. The thermoplastic resin film is not particularly limited as long as it satisfies the above numerical values. For example, low-density polyethylene (LDPE), which is a polymer film described in Toray Research Center, Inc., a new development of functional packaging materials, HDPE, linear low density polyethylene (LLDPE), medium density polyethylene, unstretched polypropylene (CPP), OPP, ONy, PET, cellophane, polyvinyl alcohol (PVA), stretched vinylon (OV), ethylene-vinyl acetate copolymer ( EVOH), ethylene-propylene copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, vinylidene chloride (PVDC), and the like can be used. Among these thermoplastic resin films, it is particularly preferable to use LDPE, LLDPE produced by using LDPE, LLDPE and a metallocene catalyst, or a film using a mixture of these films and HDPE films.

  The flexible sealing member used to form the sealing layer is a laminated film in which a barrier layer (a protective layer if necessary) is formed on the resin base material in order to facilitate handling during production. It is preferable to use it in the state. As a method for producing a laminated film, various methods generally known on the inorganic layer of a thermoplastic resin film on which an inorganic material is deposited and a thermoplastic resin film on which an aluminum foil is laminated, such as a wet laminating method and a dry laminating method. It can be made by using a method, a hot melt laminating method, an extrusion laminating method, or a thermal laminating method.

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

  The sealing member used for the configuration of the organic EL panel shown in FIG. 2 will be described. The sealing member is preferably a material that can be molded from the viewpoint of productivity, and particularly preferably a metal material from the viewpoint of handleability and strength. For example, an aluminum material or a copper material having a thickness of about 0.1 to 2 mm. , Iron material, stainless steel material and the like.

(adhesive)
Examples of the adhesive according to the present invention include a liquid adhesive, a sheet adhesive, and a thermoplastic resin. Examples of the liquid adhesive include photo-curing and thermosetting sealing agents having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, moisture-curing adhesives such as 2-cyanoacrylate, epoxy-based adhesives, etc. And heat curing and chemical curing type (two-component mixing) adhesives, cationic curing type ultraviolet curing epoxy resin adhesives, and the like. It is preferable to add a filler to the liquid adhesive as necessary. The addition amount of the filler is preferably 5 to 70% by volume in consideration of adhesive strength. In addition, the size of the filler to be added is preferably 1 μm to 100 μm in consideration of the adhesive strength, the adhesive thickness after pasting and pressure bonding, and the like. The kind of filler to be added is not particularly limited, and examples thereof include soda glass, non-alkali glass, or silica, titanium dioxide, antimony oxide, titania, alumina, zirconia, tungsten oxide, and other metal oxides.

When bonding a sealing member and an organic EL element using a liquid adhesive, the bonding part 504 has bonding stability, prevention of air bubbles mixing into the bonding part, and a plane of the flexible sealing member. It is preferable to carry out under a reduced pressure condition of 10 to 1 × 10 ⁻⁵ Pa in view of maintaining the property.

  The sheet-like adhesive refers to an adhesive 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. As an adhesive to be used, for example, a photocurable resin mainly composed of a compound having an ethylenic double bond at the terminal or side chain of a molecule and a photopolymerization initiator can be mentioned. In use, for example, it is preferable to use it at a normal temperature (about 25 ° C.) or less by pasting it on the sealing member side in advance.

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

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

(Organic EL substrate)
Examples of the organic EL substrate according to the present invention include a single-wafer sheet-like substrate and a strip-like flexible substrate. Examples of the sheet-like base material include a transparent glass plate and a sheet-like transparent resin film. 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 base material, The same resin film as a sheet-fed sheet-like base material can be used.

When using a transparent resin film as a 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, it is preferably a high barrier film having an oxygen permeability of 0.1 ml / m ² · day · MPa or less and a water vapor permeability of 10 ⁻⁵ g / m ² / day or less.

  As a material for forming the 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 barrier film is not particularly limited, and for example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster ion beam, ion plating, plasma polymerization, atmospheric pressure plasma polymerization A plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

(electrode)
In the case of an organic EL panel, since the anode (first electrode) side is usually the observation side, an electrode having a high light transmittance is used as the first electrode. 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 taken out from the anode, it is desirable that the transmittance is 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.

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 ( Cathode) can be fabricated, and by applying this, a device in which both the first electrode (anode) and the second electrode (cathode) are transmissive can be fabricated (hole transport layer)
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.

(Light emitting layer)
In 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 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, resulting in recombination of the carriers on the phosphorescent compound and from the phosphorescent compound. Although it is a carrier trap type in which light emission can be obtained, in any case, it is a condition that the excited state energy of the phosphorescent compound is lower than the excited state energy of the host compound.

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

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

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

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

(Electron injection layer)
The electron injection layer is made of a material having a function of transporting electrons and is included in the electron transport layer in a broad sense. The electron injection layer is a layer provided between the electrode and the organic layer for lowering the driving voltage and improving the luminance of the light emission. “Organic EL element and its forefront of industrialization (NST 30, November 30, 1998) Issue) ”, Chapter 2, Chapter 2,“ Electrode Materials ”(pages 123-166). 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.

  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.

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

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

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

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

  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)
An organic EL device in which the first electrode, the hole transport layer, the light emitting layer, the electron transport layer, and the second electrode were formed on the substrate in this order by the method described below was produced.

(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. Then, using a vapor deposition apparatus, using indium tin oxide (ITO) under a vacuum of 5 × 10 ⁻⁴ Pa, the deposited film formation region (first electrode formation region) of the prepared glass substrate As shown in FIG. 1, a patterned first electrode having a width of 2 mm, a length of 50 mm, an interval of 2 mm, a thickness of 150 nm, and 10 rows was formed.

(Formation of hole transport layer)
Using a glass substrate on which the first electrode is formed, N, N′-diphenyl-N, as a hole transport layer forming material in a hole transport layer forming vapor deposition apparatus under a vacuum of 5 × 10 ⁻⁴ Pa, Using N′-m-tolyl 4,4′-diamino-1,1′-biphenyl, vapor deposition (vapor phase) is formed on the first electrode except for one end of the first electrode formed on the glass substrate. Deposited).

(Formation of light emitting layer)
Each glass substrate on which a hole transport layer is formed is used, Alq ₃ is used as a light emitting layer forming material in the region where the hole transport layer is formed, and the light emitting layer is used under a vacuum of 5 × 10 ⁻⁴ Pa. Vapor deposited with a forming vapor deposition apparatus.

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

(Formation of second electrode)
Using a glass substrate on which an electron transport layer is formed, using Al as a second electrode forming material on the electron transport layer in a direction perpendicular to the first electrode as shown in FIG. 1, 5 × 10 ⁻ Al was vapor-deposited by a second electrode forming vapor deposition apparatus under a vacuum of ⁴ Pa. The formed second electrode had a width of 2 mm, a length of 35 mm, an interval of 2 mm, a thickness of 150 nm, and a 7-row pattern.
(Preparation of sealing member)
As a sealing member, a PEN film (manufactured by Teijin / Dyupon Co., Ltd.) as a base material and a sheet-shaped sealing member having a two-layer structure using an aluminum foil as a barrier layer were prepared. The PEN thickness was 100 μm, and the barrier layer thickness was 7 μm. The base material and the barrier layer were joined by a dry laminating method using a polyester adhesive, and the thickness of the sealing member after joining was 110 μm. The water vapor permeability measured by the MOCON method by a method based on the JIS K-7129B method (1992) was 0.01 g / m ² · day. The oxygen permeability measured mainly by the MOCON method by a method based on JIS K7126B method (1987) was 0.1 ml / m ² · day · MPa. The prepared sheet-shaped sealing member is matched to the size of the prepared organic EL element, and the sheet-shaped sealing member as shown in Table 1 in the form shown in FIG. A sheet-shaped sealing member having convex portions with different ratios and lengths on the end sides of the bonding surface (back surface) of No. 2 was prepared. 1-1 to 1-16. In addition, the ratio which provides a convex-shaped part shows the ratio (%) with respect to the full length of the edge side of the joining surface (back surface) of a sheet-like sealing member. The length of a convex part shows the ratio with respect to the thickness of an adhesive bond layer. As shown in FIG. 3, the length of the convex portion is the length from the edge of the joint surface (back surface) to the adhesive layer to the tip of the convex portion, as shown in FIG. The value calculated by the following formula is shown.

              Actual value of convex part / thickness of adhesive layer × 100 = length of convex part (%)

The front surface * indicates the surface opposite to the bonding surface (back surface), and the back surface * indicates the bonding surface with the adhesive layer 1 of the sealing member.
(Production of organic EL panel)
In accordance with the flow shown in FIG. 11, a thermosetting liquid adhesive (epoxy resin) is used on the bonding surface (back surface) side with the adhesive layer of the prepared sealing member, and the thickness is 30 μm by screen printing. After being placed on the entire surface, the light emitting area of the prepared organic EL device and the periphery of the light emitting area are bonded and fixed so as to cover the periphery of the light emitting area. 101-116. In addition, the pasting was performed under a pressure of 0.1 MPa in a vacuum environment of 1 Pa, and then allowed to stand for 3 hours in an environment at an atmospheric pressure of 80 ° C. to be fixed. The average thickness of the adhesive layer was 30 μm.

Evaluation Each sample No. 101 to 116 were stored for 300 hours under conditions of a temperature of 60 ° C. and a humidity of 90% RH, and then the presence or absence of dark spots (light emission unevenness) was tested by the test method shown below, and evaluated according to the evaluation rank shown below. The results are shown in Table 2.

Test method of dark spot (light emission unevenness) Using a source measure unit 2400 made by KEITHLEY, a direct current voltage was applied to the organic EL element to emit light. With respect to the light emitting element that emits light at 200 cd, it was observed whether a dark spot (light emission unevenness) occurred with a 50 × microscope.

Evaluation rank of dark spot (light emission unevenness) ◎: 90% or more emits uniformly ○: 80% or more emits uniformly △: 70% or more emits uniformly ×: Less than 70% Only emits light uniformly

  The effectiveness of the present invention was confirmed.

Example 2
(Production of organic EL element)
An organic EL element having the same layer configuration as that of Example 1 was produced.

(Preparation of sealing member)
Stainless steel with a thickness of 1.2 mm was used as the sealing member, and a container-type sealing member as shown in FIG. 10 was prepared. After the container mold sealing member is press-molded into a container mold to a required size in the form of a sheet-like stainless steel plate, the periphery is a punch / die type cutting apparatus shown in FIG. As shown, a container-type sealing member having convex portions with different ratios and lengths provided on the edges of the joining surface (back surface) of the sheet-like sealing member was prepared. 2-1 to 2-16. In addition, the ratio which provides a convex-shaped part shows the ratio (%) with respect to the full length of the edge of the joint surface (back surface) of a container type sealing member. As shown in FIG. 4, the length of the convex portion is the length from the edge of the bonding surface (back surface) side to the adhesive layer to the tip of the convex portion, as shown in FIG. Measured by Keyence), and the value calculated by the following formula is shown.

            Actual value of convex part / thickness of adhesive layer × 100 = length of convex part (%)

The front surface * indicates the surface opposite to the bonding surface (back surface), and the back surface * indicates the bonding surface with the adhesive layer 1 of the sealing member.
(Production of organic EL panel)
In accordance with the flow shown in FIG. 12, an ultraviolet curable liquid adhesive (epoxy resin / containing 20% glass spacer 1%) is used for the joint surface with the adhesive layer of the prepared sealing member, and the needle type dispensing device is used. After coating so that the width is 600 μm and the height is 500 μm, the light-emitting area of the prepared organic EL device and the periphery of the light-emitting area are pasted and fixed so that an organic EL panel is prepared. 201-216. Bonding is performed under pressure of 0.1 MPa under a reduced pressure environment of 80 kPa, and then fixed by irradiating ultraviolet light with a main wavelength of 365 nm from the organic EL substrate side in an atmospheric pressure environment (90 m at 100 mW / cm ² ). I let you. The average thickness of the adhesive layer after fixing was 20 μm.

Evaluation Each sample No. 201 to 216 were stored for 300 hours under conditions of a temperature of 60 ° C. and a humidity of 90% RH, and then the presence or absence of dark spots (light emission unevenness) was tested by the same method as in Example 1, and the same evaluation as in Example 1 was performed. The results of evaluation according to the rank are shown in Table 4.

  The effectiveness of the present invention was confirmed.

Example 3
(Production of organic EL element)
An organic EL element having the same layer configuration as that of Example 1 was produced.

(Preparation of sealing member)
Using a PEN film with a thickness of 100 μm (manufactured by Teijin and Deyupon) as a sealing member, a transparent gas barrier layer having a thickness of about 90 nm is formed by an atmospheric pressure plasma discharge treatment method, and a two-layered sheet-shaped sealing member Prepared. As a result of measuring the water vapor transmission rate by a method based on JIS K-7129B, it was 10 ⁻³ g / m ² / day or less. As a result of measuring the oxygen permeability by a method based on JIS K-7126B, it was 10 ⁻² g / m ² · day · MPa or less.
The prepared sheet-shaped sealing member is adjusted to the size of the prepared organic EL element, and the sheet-shaped sealing is performed as shown in Table 5 in the form shown in FIG. A sheet-shaped sealing member having convex portions having different ratios and lengths on the end side (end surface) of the outer periphery of the stop member was prepared. 3-1 to 3-10. In addition, the ratio which provides a convex-shaped part shows the ratio (%) with respect to the full length of the joint surface (back surface) of a sheet-like sealing member. The length of a convex part shows the ratio (%) with respect to the thickness of an adhesive bond layer. As shown in FIG. 3, the length of the convex portion is the length from the edge of the bonding surface (rear surface) side to the adhesive layer to the tip of the convex portion, as shown in FIG. Measured by Keyence), and the value calculated by the following formula is shown.

          Actual value of convex part / thickness of adhesive layer × 100 = length of convex part (%)

  The front surface * indicates the surface opposite to the bonding surface (back surface), and the back surface * indicates the bonding surface with the adhesive layer 1 of the sealing member.

(Production of organic EL panel)
In accordance with the flow shown in FIG. 11, an ultraviolet curable liquid adhesive (epoxy resin) is used on the bonding surface side of the prepared sealing member with the adhesive layer, and the entire surface is arranged to a thickness of 30 μm by screen printing. After that, the prepared organic EL element was bonded and fixed so as to cover the light emitting region and the periphery of the light emitting region, and an organic EL panel was prepared. 301 to 310. Bonding is performed under pressure of 0.1 MPa in a 1 Pa vacuum environment, and then irradiated with ultraviolet light having a main wavelength of 365 nm from the sealing member side in an environment at an atmospheric pressure of 80 ° C. (90 m at 100 mW / cm ² ). It was fixed by. The average thickness of the adhesive layer was 30 μm.

Evaluation Each sample No. 301 to 310 were stored for 300 hours under conditions of a temperature of 60 ° C. and a humidity of 90% RH, and then the presence or absence of the occurrence of dark spots (light emission unevenness) was tested by the same method as in Example 1, and the same evaluation as in Example 1 The results of evaluation according to the rank are shown in Table 6.

  The effectiveness of the present invention was confirmed.

It is the schematic which shows an example of a structure of an organic electroluminescent panel. It is the schematic which shows an example of the other structure of an organic electroluminescent panel. FIG. 2 is an enlarged schematic view of a portion indicated by S in FIG. 1. FIG. 3 is an enlarged schematic view of a portion indicated by T in FIG. 2. It is the schematic of the punch cutting apparatus by a punch die. FIG. 6 is an enlarged schematic view of a portion indicated by U in FIG. FIG. 6 is a schematic view of a punching blade (engraving blade) and a punching blade cradle used instead of the punch and the lower die shown in FIG. 5. FIG. 8 is a schematic view showing the relationship between the blade and the sealing member when the sealing member is cut with a cutting device. It is the schematic of the sealing member used in manufacturing the organic electroluminescent panel shown by FIG. It is the schematic of the container type sealing member used in manufacturing the organic EL panel shown by FIG. It is a schematic flowchart which manufactures the organic electroluminescent panel shown by FIG. It is a schematic flowchart which manufactures the organic electroluminescent panel shown by FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a, 1b Organic EL panel 101 Base material 102 Organic EL element 102a Anode layer 102b Hole transport layer (hole injection layer)
102c Organic compound layer (light emitting layer)
102d Electron injection layer 102e Cathode layer 103, 106 Adhesive layer 103a Surface 104 Sealing member 104a, 105a Surface 104b, 105b Bonding surface (back surface)
104c, 105c Edge line 104d, 105d End face 104e, 105e Face 104e1, 104e2, 105e1, 105e2 End 105 Container type sealing member 2 Punching cutting device 201 Punch (upper blade)
204 Die (lower blade)
3 Punching blades θ1, θ2, θ3 Angle J Clearance (gap)
E, E ', F, F' Length

Claims (9)

An organic electroluminescent device having an anode layer including at least a first electrode, an organic compound layer including a light-emitting layer, and a cathode layer including a second electrode on a substrate is disposed at least on the organic electroluminescence element via an adhesive layer. In the organic electroluminescence panel having a structure sealed with a sealing member that seals the surface of the luminescence element, the sealing member is formed on the edge of the bonding surface (back surface) with the adhesive layer. A convex portion facing toward the side, and the length of the convex portion is 10 with respect to the thickness of the adhesive layer on the basis of the joint surface (back surface) with the adhesive layer on the end side. An organic electroluminescence panel characterized in that the organic electroluminescence panel is in a range of% to 200%. 2. The organic electroluminescence panel according to claim 1, wherein the convex portion is provided in an amount of 10% or more with respect to a total length of an outer peripheral edge of the sealing member. At least the organic electroluminescence element having an anode layer including at least a first electrode, an organic compound layer including a light emitting layer, and a cathode layer including a second electrode on a substrate via an adhesive layer. In the method of manufacturing an organic electroluminescence panel having a structure sealed with a sealing member that seals the surface of the element, the sealing member is formed on the end surface of the bonding surface (back surface) with the adhesive layer. On the basis of the (back surface), a convex portion that is 10% to 200% with respect to the thickness of the adhesive layer is integrally provided, and the adhesive layer is used as the sealing member or the organic electroluminescence element. Then, the sealing member is disposed on the organic electroluminescence element and the convex portion is directed toward the substrate. Allowed method of producing an organic electroluminescent panel, characterized in that sealing the organic electroluminescence device. The method for manufacturing an organic electroluminescence panel according to claim 3, wherein the convex portion is provided in an amount of 10% or more with respect to the entire length of the outer peripheral edge of the sealing member. The method for manufacturing an organic electroluminescence panel according to claim 3 or 4, wherein the sealing member is manufactured by a cutting method. 6. The organic electroluminescence panel according to claim 5, wherein, when the cutting method is push-cut cutting, cutting is performed by inserting a cutting blade from a surface (surface) opposite to a bonding surface with the adhesive layer of the sealing member. Production method. When the cutting method is a punch die method having an upper blade and a lower blade, a joining surface (back surface) where at least one of the upper and lower blades is joined to the adhesive layer of the sealing member; 6. The method of manufacturing an organic electroluminescence panel according to claim 5, wherein the cutting is performed so as to be in contact with each other. The cutting method is a punch die method having an upper blade and a lower blade, and the clearance between the upper blade and the lower blade is 1% to 150% with respect to the thickness of the sealing member. The manufacturing method of the organic electroluminescent panel of Claim 5. The cutting method is a punch die method having an upper blade and a lower blade, and the clearance between the upper blade and the lower blade is 1% to 150% with respect to the thickness of the sealing member, 6. The organic electroluminescence according to claim 5, wherein cutting is performed such that at least one of the upper blade and the lower blade is in contact with a bonding surface (back surface) to be bonded to the adhesive layer of the sealing member. Panel manufacturing method.

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