JP2009238474A - Organic electroluminescent element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL element for actualizing easy patterning of a light emitting part while giving no adverse effects on an organic layer such as a light emitting layer during the patterning. <P>SOLUTION: In the organic EL device 1, the organic layer 13 including the light emitting layer 5 is held between an anode 3 and a cathode 7, and an anode substrate 11 on which the organic layer 13 and the anode 3 are formed and a cathode substrate 12 on which a sub electrode layer 71, a main electrode layer 72 and a pattern forming layer 6 are formed are pasted to each other. The main electrode layer 72 on a portion of the pattern forming layer 6 is formed as a crack portion 14. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an organic electroluminescence device formed by sandwiching an organic material layer including a light emitting layer between a pair of electrodes and emitting light in a predetermined pattern.

  In an organic electroluminescence element (hereinafter referred to as an organic EL element), a thin film (light emitting layer) containing a light emitting organic material is sandwiched between a cathode substrate provided with a cathode and an anode substrate provided with an anode. Have a structure. In an organic EL element, when a low voltage is applied between both electrodes and a current flows, holes are injected from the anode into the light emitting layer and electrons are injected from the cathode, and the holes and electrons are regenerated inside the light emitting layer. It is a self-luminous element that utilizes light (fluorescence, phosphorescence, etc.) that is emitted when it is coupled to an excited state and returns to the ground state.

  As a means for causing the light emitting surface of the organic EL element to emit light in a predetermined pattern, for example, an insulating layer is inserted between the electrodes where it is not desired to emit light, and carrier injection and carrier recombination from the electrodes are impossible due to the insulating layer In addition, an organic EL element in which a portion of the insulating layer is a non-light emitting portion and a portion where no insulating layer is provided is a light emitting portion is known (see Patent Document 1). In Patent Document 1, as a means for forming an insulating layer in a pattern, a pattern is formed by a photolithography technique using an insulating photoresist, and a pattern-like insulation is formed by a thin film forming method such as vacuum deposition, sputtering, or coating. The formation of a layer is described.

  Also, as a means for forming the insulating layer in a pattern, after forming the entire surface of the insulating layer on the surface of the electrode layer, the composition of the light emitting layer is applied to the surface of the insulating layer in a predetermined pattern using an inkjet device. A so-called self-alignment method is known in which a light emitting layer is formed in a predetermined pattern by mixing an insulating layer and a light emitting layer at a portion where the light emitting layer is applied.

  As a means for forming the insulating layer in a pattern, the insulating layer is formed in a predetermined pattern directly on the surface of the organic layer including the light emitting layer provided on the electrode by a printing method such as screen printing or gravure printing. Printing methods are known.

Japanese Patent Laid-Open No. 10-270173

  The method of forming an insulating layer in a predetermined pattern using the photolithography method described in Patent Document 1 described above is capable of high-definition patterning, but has a problem that it requires a lot of processing steps and is very troublesome. Further, when a glass plate is used as the substrate of the organic EL element, processing is possible, but when a resin film or the like that is easily deformed is used as the substrate, there is a problem that accurate pattern formation is difficult.

  Further, the method of forming the insulating layer in a pattern by the self-alignment method has a problem that the components of the insulating layer are easily mixed in the light emitting layer, and the light emission characteristics are likely to be deteriorated.

  In addition, the method of forming the insulating layer in a pattern by a printing method is included in the insulating layer composition because the insulating layer composition containing an organic solvent is applied to the surface of the organic layer when forming the insulating layer. There are problems that the organic material layer is altered or deformed by the solvent, or that the organic material layer is thermally deteriorated or deformed by heat during drying.

  The problem to be solved by the present invention is to solve the above-mentioned problems. In an organic EL element formed so as to emit light in a predetermined pattern, the light-emitting pattern can be easily patterned. It is another object of the present invention to provide an organic EL element that does not have an adverse effect on an organic layer such as a light emitting layer.

  In order to solve the above-described problems, an organic EL device according to the present invention includes an organic material layer including at least a light emitting layer between an anode and a cathode, and the organic material layer and one electrode are formed on a first substrate. An organic electroluminescent element obtained by bonding a first substrate and a second substrate having the other electrode formed on a second base material, at least a cathode or an anode having a sub-electrode layer and a main electrode A pattern forming layer comprising a non-light emitting pattern of an element is provided between the sub electrode layer and the main electrode layer, the sub electrode layer is formed on the substrate side, and the pattern forming layer The gist is that a crack portion is formed in the portion of the electrode layer.

  In the organic EL element, the pattern formation layer is preferably formed on the second substrate side or a resin layer.

  In the organic EL element, the electrode of the first substrate is preferably an anode, and the electrode of the second substrate is preferably a cathode.

  In the organic EL device, the organic layer is preferably composed of a light emitting layer and a hole transport layer.

  According to the organic EL device of the present invention, the pattern forming layer is formed between the sub electrode layer and the main electrode layer, and the electrode layer corresponding to the pattern forming layer is formed as a crack. Since the crack portion is formed with higher resistance than the electrode portion other than the crack portion and does not function as an electrode, the crack portion portion can be configured as a non-light emitting portion of the organic EL element. Therefore, the present invention eliminates the need for patterning the electrode using a mask method or the like in a vacuum during the manufacture of the organic EL element, and forms the electrode on one side only and bonds the anode substrate and the cathode substrate together. With this simple operation, an organic EL element in which a crack corresponding to the shape of the pattern forming layer is formed on the electrode can be obtained, and patterning can be easily performed.

  In the organic EL device of the present invention, since the pattern forming layer exists between the sub electrode layer and the main electrode layer, it is not necessary to form the pattern forming layer directly on the organic layer such as the light emitting layer. Therefore, in the present invention, the organic layer is altered or deformed by the solvent contained in the insulating layer composition, as in the case of an organic EL device in which the conventional insulating layer composition is applied to the surface of the organic layer, or the organic layer is There is no risk of thermal degradation or deformation due to heat during drying.

  In addition, the organic EL device of the present invention does not need to form a pattern forming layer directly on the organic material layer. Therefore, like the method of forming an insulating layer on the light emitting layer in a pattern by a conventional self-alignment method, There is no possibility that the components of the insulating layer are mixed in the organic material layer such as the light emitting layer and the light emitting characteristics are deteriorated.

  Further, in the organic EL element of the present invention, the pattern forming layer is formed to have such a hardness that cracks are formed in the electrode in contact with the pattern forming layer by the pressure at the time of bonding between the first substrate and the second substrate. Therefore, it is not necessary to form a pattern by vacuum deposition or the like like patterning of the electrode layer, and the pattern can be formed at normal pressure. Conventionally, when patterning is performed in a vacuum, there is a problem that accuracy is low and productivity is low, but if the pattern forming layer is formed at normal pressure, the above problem does not occur.

  According to the organic EL device of the present invention, the pattern forming layer provided between the sub electrode layer and the main electrode layer only needs to have a certain level of insulation that can prevent leakage current. Furthermore, since the electrode layer (main electrode layer) formed on the surface of the pattern forming layer is cracked when the first substrate and the second substrate are bonded together, and the portion does not function as an electrode, It is possible to select from a wide range of materials and structures that have little effect on the organic layer fabrication process and device characteristics.

  Hereinafter, the organic EL element of the present invention will be described in detail with reference to the drawings. FIG. 1A is a cross-sectional view showing an anode substrate and a cathode substrate before bonding, and FIG. 1B is a cross-sectional view showing the organic EL element after bonding in FIG. In the drawings, the vertical direction (thickness direction) which is the vertical direction in the figure is shown by a scale enlarged 1000 times or more with respect to the horizontal direction which is the horizontal direction in the figure.

  As shown in FIGS. 1A and 1B, in the organic EL element 1, an organic layer 13 including at least a light emitting layer 5 is sandwiched between an anode 3 and a cathode 7, and the organic layer 13 and the anode 3 ( An anode substrate 11 (first substrate) in which one electrode) is formed on the anode substrate 2 (first substrate), and a cathode 7 (the other electrode) is a cathode substrate 8 (second substrate). It is obtained by bonding the cathode substrate 12 (second substrate) formed on the substrate. The cathode 7 (electrode) of the cathode substrate 12 includes a sub electrode layer 71 and a main electrode layer 72. The sub electrode layer 71 is formed on the cathode base material 8 side, and the main electrode layer 72 is formed on the organic material layer 13 side. Further, the pattern forming layer 6 is formed between the sub electrode layer 71 and the main electrode layer 72. The main electrode layer 72 in the pattern forming layer 6 of the organic EL element 1 is formed as a crack 14.

  The crack portion 14 is formed by a pressure generated by bonding the anode substrate 11 and the cathode substrate 12 together. In a state before the anode substrate 11 and the cathode substrate 12 are bonded together, the sub-electrode 71 and the main electrode layer 72 of the cathode 7 are formed over the entire surface. When the anode substrate 11 and the cathode substrate 12 are bonded, if pressure is applied to the main electrode layer 72 of the cathode 7, the pressure is locally applied to the thin film of the main electrode layer 72 where the pattern forming layer 6 exists. become. When pressure is locally applied to the electrode thin film of the main electrode layer 72, the portion is destroyed and a crack is generated. If cracks occur in the main electrode layer 72, the electric resistance increases and the function as an electrode cannot be exhibited. In this way, the portion of the main electrode layer 72 that contacts the pattern forming layer 6 is formed as a crack portion 14 corresponding to the shape of the pattern forming portion. The organic EL element 1 is formed as a non-light-emitting portion where the cracked portion 14 of the cathode 7 is formed, that is, the portion where the pattern forming layer 6 is provided and does not emit light, and the light emission where the portion other than the portion where the pattern forming layer 6 is provided emits light. It is formed as a part.

  The crack portion 14 is formed in the main electrode layer 72 on the organic material layer 13 side of the cathode layer 7. In order to form the crack portion 14 in the main electrode layer 72, a material that is easier to break than the sub electrode layer 71 is used for the main electrode layer 72, or the film thickness of the main electrode layer 72 is smaller than the film thickness of the sub electrode layer 71. And so on.

  In the organic EL element 1 shown in FIG. 1B, the layers other than the pattern forming layer 6, that is, the sub-electrode layer 71, the main electrode layer 72, the anode 3, the hole transport layer 4, and the light emitting layer 5 are all solid. Only the pattern forming layer 6 is formed in a predetermined pattern. The organic EL element 1 shown in FIG. 1 only needs to form the pattern forming layer 6 in a portion where it is not desired to emit light, and the sub-electrode layer 71 and the main electrode layer 72 of the cathode 7 are formed on the entire surface. The pattern-shaped crack part 14 is formed in the organic EL element 1 having a predetermined light emission pattern.

  The pattern forming layer 6 may be a material having a hardness capable of generating a crack in the main electrode layer 72 in contact with the pattern forming layer 6 by a pressure of pressure applied when the cathode substrate 12 and the anode substrate 11 are bonded together. The material is not particularly limited. For example, the pattern forming layer 6 can be formed of a resin layer. If the pattern forming layer 6 is formed of a resin layer, the pattern forming layer 6 can be formed by a simple means such as coating and is easy to form. As a material used for the pattern forming layer 6, for example, an epoxy resin, a polyamide resin, a urethane resin, a silicone resin, a polyester resin, a polyolefin resin, a metal alkoxide compound, or the like can be used. In addition, the pattern forming layer 6 may be modified by modifying the resin to give adhesion, combining the resins, or adding a metal filler or a carbon-based filler. The pattern forming layer 6 has a thickness of 100 nm to 10 μm, preferably 300 nm to 1 μm. If the thickness of the pattern formation layer 6 is less than 100 nm, the insulating property may be lowered, and if it exceeds 10 μm, the step becomes large and the conductivity between the sub electrode layer 71 and the main electrode layer 72 may become unstable.

  The method for forming the pattern forming layer 6 is not particularly limited as long as it does not adversely affect the properties of the cathode when the layer is formed. As a method for forming the pattern forming layer 6, for example, a printing method or a transfer method can be used. The printing method is a method of printing by screen printing, ink jet printing, gravure printing or the like using a coating liquid for a pattern forming layer. Since the pattern forming layer 6 is formed on the surface of the electrode such as the cathode (sub-electrode layer), the adverse effect that the solvent or resin of the coating solution has on the electrode (sub-electrode) during the formation of the pattern forming layer 6 The influence is small compared with the case where the solvent or resin of the liquid directly contacts the surface of the organic layer.

  Further, in order to form the pattern forming layer 6 by a transfer method, the transfer layer is transferred using a pattern transfer film in which the pattern forming layer 6 is provided as a transfer layer on the surface of the transfer substrate with the above-described pattern forming layer coating solution. Form. When the pattern forming layer 6 is formed by the transfer method, each layer constituting the organic EL element 1 and the coating liquid of the pattern forming layer 6 are not in direct contact with each other, and the influence of the solvent, heat, etc. due to the coating on the electrode or the like There is no.

  The main electrode layer 72 constituting the cathode 7 is formed of a metal having a low work function (4 eV or less), an alloy composition, a conductive compound, or a mixture thereof. Materials for the electrode layer 72 include metals such as Al, Ti, In, Na, K, Mg, Li, Cs, Rb, and rare earth metals, Na—K alloys, Mg—Ag alloys, Mg—Cu alloys, and Al. An alloy composition such as -Li alloy may be mentioned. As a material of the sub-electrode layer 71, any material having conductivity can be used in addition to the material used for the main electrode layer 72 described above. The sub electrode layer 71 and the main electrode layer 72 may be either the same material or different materials. The thickness of the sub electrode layer 71 is preferably 0.1 μm to 50 μm. The thickness of the electrode layer 72 is preferably 5 nm to 500 nm. If the thickness of the sub-electrode layer 71 is less than 5 nm, the composition of the film itself may be unstable, and if it exceeds 500 nm, the film thickness may not be practical. The resistance of the sub electrode layer 71 and the main electrode layer 72 is several hundred Ω / sq. The following is preferred. The main electrode layer 72 can be formed by a vacuum deposition method, a vacuum sputtering method, or the like. The sub-electrode layer 71 can be formed by bonding a printing method or a metal / conductive film in addition to a vacuum deposition method or a vacuum sputtering method.

  As the anode substrate 2 and the cathode substrate 8, a ceramic substrate such as a glass substrate, a resin plate, a resin film, or the like can be used. The anode substrate 2 and the cathode substrate 8 are preferably resin films. Examples of the resin for the resin film include polyesters such as polyethylene naphthalate and polyethylene terephthalate, polycarbonate, polyimide, polyether sulfone, polyether imide, polyphenylene sulfide, polysulfone, polyether ether ketone, polyamide, polymethyl methacrylate, and polyarylate. And cycloolefin polymers. The thickness of the anode substrate 2 and the cathode substrate 8 is usually 3 to 1000 μm, preferably 10 to 500 μm, more preferably 10 to 300 μm. In addition, a transparent material is normally used for the anode base material 2, the anode 3, the hole transport layer 4, and the like that are located on the light emitting surface side with respect to the light emitting layer 5 of the organic EL element 1.

  The anode substrate 2 and the cathode substrate 8 are preferably subjected to moisture-proof treatment such as barrier layer formation on the surface (one side or both sides). Examples of the barrier layer include thin films or metal films such as silicon oxide (SiO), silicon nitride (SiN), and silicon nitride oxide (SiO, SiN). In the case of using a metal film, it is formed to a thickness that allows the light generated in the light emitting layer to be taken out of the organic EL element. The thickness of the barrier layer is preferably 10 nm to 1 μm. If the thickness of the barrier layer is less than 10 nm, the barrier effect may be reduced. If the thickness exceeds 1 μm, the film base material may be easily cracked when bent.

  The anode 3 is formed from a metal having a high work function (4 eV or more), a conductive compound, or a mixture thereof. Examples of the material of the anode 3 include ITO (tin-doped indium oxide) and IZO (indium zinc oxide). The thickness of the anode 3 is usually 1 μm or less and preferably 200 nm or less. The resistance of the anode 3 is several hundred Ω / sq. The following is preferred. The anode 3 can be formed by a vacuum deposition method, a sputtering method, a spin coating method, a casting method, an LB method, a pyrosol method, a spray method, or the like.

  Examples of the hole transport layer 4 include phthalocyanine, polyaniline, oligothiophene, benzidine derivatives, triphenylamine, pyrazoline derivatives, and triphenylene derivatives. The hole transport layer 4 can be formed using a vacuum deposition method, a spin coating method, a casting method, an LB method, a printing method, or the like. The thickness of the hole transport layer 4 is preferably 2 to 200 nm. As a material for the hole transport layer 4, water-soluble PEDOT: PSS (polystyrene sulfonic acid-doped polyethylene dioxythiophene) is one of preferable materials. The hole transport layer 4 can be formed by diluting PEDOT: PSS in an alcohol solvent such as isopropyl alcohol, applying it by spin coating, and heating and drying.

  The light-emitting layer 5 is formed from an organic light-emitting material, or a small amount of organic light-emitting material in an organic material (hereinafter referred to as a host material) exhibiting carrier transport properties (hole transport property, electron transport property, or amphoteric transport property) It can form from the material which added. The light emission color of the organic EL element 1 can be set by selecting an organic light emitting material used for the light emitting layer 5. The thickness of the light emitting layer 5 is preferably 200 nm or less in order to obtain practical light emission luminance.

When the light emitting layer 5 is formed from an organic light emitting material, a material having excellent film forming properties and excellent film stability is used as the organic light emitting material. As such an organic light-emitting material, a metal complex represented by Alq ₃ (tris- (8-hydroxyquinolinato) aluminum), a polyphenylene vinylene (PPV) derivative, a polyfluorene derivative, or the like is used. As the organic light-emitting material used together with the host material, since the addition amount is small, in addition to the organic light-emitting material, a fluorescent dye that is difficult to form a stable thin film by itself can be used. Examples of fluorescent dyes include coumarin, DCM derivatives, quinacridone, perylene, and rubrene. Examples of the host material include Alq ₃ , TPD (triphenyldiamine), an electron transporting oxadiazole derivative (PBD), a polycarbonate-based copolymer, and polyvinyl carbazole. Even when the light emitting layer 5 is formed of an organic light emitting material as described above, a small amount of an organic light emitting material such as a fluorescent dye can be added in order to adjust the light emission color.

  In the organic EL device 1 of the present invention, it is sufficient that at least the light emitting layer 5 is formed as the organic layer 13 between the anode 3 and the cathode 7. In order to improve the light emitting characteristics of the light emitting device, the light emitting layer In addition to 5, the hole transport layer 4 or other layers, such as an electron transport layer, a hole injection layer, and an electron injection layer, may be provided at predetermined positions to form the organic layer 13. Good.

  Hereinafter, the manufacturing method of the organic EL element shown in FIG. 1 will be described. The organic EL element 1 includes an anode substrate 11 (first substrate) in which an anode substrate 2 made of a resin film is provided with an organic material layer 13 including an anode 3, a hole transport layer 4, and a light emitting layer 5, and a resin film A cathode substrate 12 (second substrate) in which a sub-cathode 71, a pattern forming layer 6, and a main electrode layer 72 are provided on a cathode substrate 8 made of It can be manufactured by bonding both substrates so that the light emitting layer 5 and the cathode 7 are in contact with each other.

  2A to 2C are cross-sectional views showing the manufacturing process of the cathode substrate. In the manufacturing method of the cathode substrate 12, as shown in FIG. 5A, the sub electrode layer 71 is formed on the entire surface of the cathode base material 8 by vacuum deposition or the like. Next, as shown in FIG. 2B, a pattern forming layer 6 having a predetermined pattern is formed on the surface of the sub-electrode layer 71. Then, as shown in FIG. 6C, the main electrode layer 72 is formed on the entire surface of the pattern forming layer 6 by vacuum deposition or the like, and the cathode substrate 12 is obtained. The pattern forming layer 6 can be formed into a predetermined pattern using a printing method or a transfer method.

  3A to 3D are cross-sectional views showing the process for producing the pattern transfer film. In order to manufacture the pattern transfer film 20, first, as shown in FIG. 1A, a transfer base material 21 having releasability with respect to the transfer layer is prepared. Next, as shown in FIG. 2B, the transfer layer composition made of the material of the pattern forming layer 6 is applied to the entire surface of the transfer base material 21 by gravure printing or the like and dried to form the transfer layer 22. To do. Next, as shown in FIG. 3C, a release sheet 23 having a higher release property with respect to the transfer layer 22 than the transfer substrate 21 is laminated on the surface of the transfer layer 22. Then, as shown in FIG. 4D, the transfer layer 22 is formed in the shape of the pattern formation layer 6 by removing the portion corresponding to the light emitting portion by using a Thomson mold or the like, and patterning it. A patterned transfer film 20 is obtained.

  As the punching method, in addition to the method using the Thomson die, a punching method using a die, or a male and female die having a punching blade on the upper die and the lower die capable of more complicated punching is used. Methods and the like. A method of punching and removing the shape of the light emitting portion to form the pattern forming layer 6 may be an extremely simple operation as the pattern forming means, and pattern formation is easy. The pattern forming layer 6 may be previously patterned on the transfer film by gravure printing or the like.

  As the transfer base material 21 and the release sheet 23, a resin film having releasability with respect to the transfer layer 22 is used. For example, a polyester film such as a polyethylene terephthalate film having a thickness of about 3 to 1000 μm can be used as the resin film. The surface of the resin film can be appropriately subjected to a release treatment in order to adjust the release property with respect to the transfer layer.

  Forming the pattern forming layer 6 on the transfer layer 22 has the following advantages. Conventionally, when an insulating layer is patterned on the surface of the cathode, an active material having a good electron-injecting property is often used for the cathode, so that it is necessary to perform patterning together when forming the cathode in a vacuum. However, when patterning is performed in a vacuum in this way, the manufacturing method is limited to the mask method or the like. On the other hand, when the pattern forming layer is formed on the transfer substrate, it is not necessary to form the pattern forming layer under vacuum, and the pattern forming layer can be formed at atmospheric pressure, so that patterning can be easily performed.

  In order to form the pattern forming layer 6 using the pattern transfer film 20, the pattern transfer film 20 release sheet 23 is peeled off and laminated so that the transfer layer 22 and the sub electrode layer 71 are in contact with the surface of the sub electrode layer 71. After the pressure is applied, the transfer substrate 21 is peeled off, whereby the transfer layer 22 is transferred and the pattern forming layer 6 is formed.

  The anode substrate 11 is obtained by sequentially forming the anode 3, the hole transport layer 4, and the light emitting layer 5 on the surface of the anode base 2 on the entire surface.

  FIG. 4 is an explanatory diagram of the bonding process of the anode substrate and the cathode substrate. As shown in FIG. 4, the anode substrate 11 and the cathode substrate 12 are laminated so that the light emitting layer 5 and the main electrode layer 72 of the cathode 7 are in contact with each other. And And this laminated body is passed between a pair of heating rollers 41 and 42, and a laminated body is heated and pressurized. When the laminate is pressed, the anode substrate 11 and the cathode substrate 12 are joined and integrated to obtain the organic EL element 1. The method for heating / pressing the anode substrate 11 and the cathode substrate 12 is not limited to the above method using a pair of rollers, for example, a method using a pair of heating rollers, a method using a pair of heating plates, or heating. A method of combining a roller and a heating plate can be used.

  Due to the pressure in the bonding process, the main electrode layer 72 of the cathode substrate 12 is locally pressurized at the portion in contact with the pattern forming layer 6, cracks are generated, and the cracks 14 are formed. The pressure in the bonding step is preferably 0.1 MPa to 10 MPa for the reason that the film substrate constituting the anode and the cathode and the organic substance layer therebetween can be appropriately deformed. Moreover, the temperature of the heating rollers 41 and 42 in the bonding step can be appropriately selected according to the thermal characteristics of the films constituting the anode and cathode substrates to be used and the organic material layer therebetween.

  The organic EL element of the above aspect includes an anode substrate (first substrate) having an organic layer including a light emitting layer on the anode side, a cathode composed of a sub-electrode layer and a main electrode layer, and the sub-electrode layer and the main electrode layer. Although the cathode substrate (second substrate) in which the pattern forming layer is formed between the electrode layers is bonded, the present invention is not limited to this embodiment. For example, in the organic EL device of the present invention, an organic layer may be formed on the cathode side to form a first substrate, and the anode side may be configured as a second substrate. In the organic EL device of the present invention, the anode may be composed of the sub-electrode and the main electrode, and a pattern forming layer may be formed between the anode and the anode substrate as the first substrate or the second substrate.

Examples of the present invention will be described below.
Example 1
(1-1) Production of Cathode Substrate As a cathode support film (cathode base material), a polyethylene naphthalate (PEN) film having a thickness of 100 μm is formed in advance on both sides of SiO ₂ and SiN as barrier layers, and further on one side, a sub-electrode As a layer, Ag was vacuum-deposited to a thickness of 200 nm. Next, a pattern forming layer was produced on the sub-electrode layer as follows.

  A pattern forming coating solution (polyamide-based resin and epoxy resin diluted with toluene and methanol) was patterned on the sub-electrode layer in a predetermined pattern directly on the sub-electrode. Then, it vacuum-dried at 0.1 MPa and 80 degreeC for 5 minutes, and formed the pattern formation layer of thickness 1 micrometer. Further, MgAg was formed on the surface of the pattern forming layer to a thickness of 50 nm with a vacuum film forming apparatus to form this electrode layer to obtain a cathode substrate.

(1-2) Production of anode substrate A polyethylene naphthalate (PEN) film having a thickness of 220 μm was used as an anode base material, and SiO ₂ and SiN were previously formed on both sides of the film as barrier layers, and further on one side as an anode. Indium tin oxide (ITO) was deposited to a thickness of 150 nm to form an anode substrate.

(1-3) Cleaning The anode substrate was subjected to ultrasonic cleaning for 5 minutes each in the order of pure water, organic alkali cleaning liquid (Furuuchi Chemical Co., Ltd .: Semico Clean), pure water, and acetone solution. Then, it processed for 30 minutes with the UV ozone cleaner.

(1-4) Formation of hole transport layer On the surface of the anode of the cleaned anode substrate, a coating liquid for forming a hole transport layer [PEDOT: PSS aqueous solution (manufactured by Starck) diluted with IPA] The film was applied by spin coating under the condition of a rotational speed of 2000 rpm × 60 seconds and dried in an oven at 120 ° C. for 30 minutes to form a hole transport layer having a thickness of 100 nm.

(1-5) Formation of Light-Emitting Layer The surface of the hole transport layer of the anode substrate is spin-coated with a polyfluorene-based light-emitting material (glass transition temperature: 116 ° C., DSC method) as the light-emitting layer material to a thickness of 80 nm. It was applied by the method and dried to form a light emitting layer on the entire surface.

(1-6) Production of Organic EL Element The cathode substrate of the above (1-1), the anode substrate provided with the hole transport layer and the light emitting layer of (1-5), the light emitting layer, the main electrode layer, Are superposed so that they are in contact with each other, passed between two heating rolls set at a temperature of 140 ° C., the anode substrate and the cathode substrate are pressurized at a roll pressure of 2 MPa, and both are joined together. The organic EL element of Example 1 in which the portion of the main electrode layer in contact with the pattern forming layer was formed as a crack by pressure was obtained.

Example 2
Implemented except that the pattern forming layer was formed on the sub-electrode layer of the cathode support film (cathode base material) by the following transfer method, and this electrode layer was formed on the pattern forming layer to obtain the cathode base material. In the same manner as in Example 1, an organic EL device was obtained.

  After gravure printing a transfer layer forming coating liquid (polyamide resin and epoxy resin diluted with toluene and methanol) on the surface of a polyethylene terephthalate (PET) film that has been subjected to a release treatment as a transfer substrate, 0.1 MPa, Vacuum-dried at 80 ° C. for 5 minutes to form a transfer layer having a thickness of about 250 nm on the entire surface. Further, a laminate of transfer substrate / transfer layer / release film is formed on the surface of the transfer layer by laminating a PET film having a higher release property to the transfer layer than the PET film of the transfer substrate as a release sheet. did. This laminate was punched out with a Thomson die at a portion corresponding to the T-shaped light emitting portion to obtain a pattern transfer film in which a transfer layer was formed in a pattern of a non-light emitting portion. The release film of this pattern transfer film was peeled off and transferred onto the surface of the sub electrode layer to form a pattern forming layer.

An example of the organic EL element of this invention is shown, (a) is sectional drawing which shows the anode substrate and cathode substrate before bonding, The figure (b) is the organic EL element after bonding of the figure (a). FIG. (A)-(c) is sectional drawing which shows the manufacturing process of a cathode substrate. (A)-(d) is sectional drawing which shows the manufacturing process of a pattern transfer film. It is explanatory drawing of the bonding process of an anode substrate and a cathode substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic luminescence (EL) element 2 Anode base material 3 Anode 4 Hole transport layer 5 Light emitting layer 6 Pattern formation layer 7 Cathode 71 Sub electrode layer 72 Main electrode layer 8 Cathode base material 11 Anode substrate (first substrate)
12 Cathode substrate (second substrate)
13 Organic layer 14 Crack

Claims (5)

  A first substrate in which an organic layer including at least a light emitting layer is sandwiched between an anode and a cathode, the organic layer and one electrode are formed on a first substrate, and the other electrode is a second substrate. An organic electroluminescence element obtained by bonding together a second substrate formed on the substrate, wherein at least a cathode or an anode comprises a sub-electrode layer and a main electrode layer, and the sub-electrode layer and the main electrode layer A pattern forming layer comprising a non-light emitting pattern of an element is provided between the sub electrode layers on the substrate side, and a crack is formed in the main electrode layer portion of the pattern forming layer. An organic electroluminescence element.   The organic electroluminescence element according to claim 1, wherein the pattern formation layer is formed on the second substrate side.   The organic electroluminescent element according to claim 1, wherein the pattern forming layer is a resin layer.   The organic electroluminescent element according to claim 1, wherein the electrode of the first substrate is an anode and the electrode of the second substrate is a cathode.   The organic electroluminescent device according to any one of claims 1 to 4, wherein the organic layer is composed of a light emitting layer and a hole transport layer.

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