JP2013089561A - Organic el device and method of manufacturing organic el device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the stability of initial light emission and prevent deterioration in a hot and humid environment even when an insulating smooth layer is provided when a conductive base material such as metal is used as a substrate. An organic EL device that can be manufactured and a manufacturing method thereof are provided.
An organic EL device 100 having a conductive substrate 101, having an insulating smooth layer 102 on the conductive substrate 101, a gas barrier layer 120 on the insulating smooth layer 102, and on the gas barrier layer 120. The organic EL element 110 is included, the gas barrier layer 120 includes at least one of a metal and a semimetal, the gas barrier layer 120 includes a discharge treatment layer 120b that has been subjected to a discharge treatment, and a non-discharge treatment layer that has not been subjected to a discharge treatment. 120a.
[Selection] Figure 1

Description

  The present invention relates to an organic EL device and a method for manufacturing the organic EL device.

  Organic EL (electroluminescence) devices have been found to be degraded by moisture and oxygen in the atmosphere. Therefore, a low moisture-permeable material such as glass or metal is used as a substrate on which the organic EL element is formed and a sealing plate for the formed organic EL element. In recent years, development of flexible devices has been promoted, and it has been studied to use a conductive base material such as metal foil as a substrate for flexible devices. The conductive base material such as the metal foil is good for the use from the viewpoints of heat resistance and heat dissipation. However, in the said use, it is necessary to ensure insulation and smoothness. Therefore, generally, an organic resin is provided as an insulating smoothing layer. However, since this insulating smooth layer has high moisture permeability, the initial light emission of the organic EL device becomes unstable (decrease in luminance), and there is a problem that the light emission state is easily deteriorated in a high temperature and high humidity environment. Therefore, it has been studied to further provide a barrier layer on the insulating smooth layer (see, for example, Patent Document 1). However, the barrier layer obtained by a general film forming method such as sputtering is not flexible, and there is a problem that when the flexible device is bent, the barrier layer cracks and the light emitting state is deteriorated.

  Further, there is a method in which the entire insulating smooth layer is covered with a glass cap or the like and a hygroscopic material is enclosed (see, for example, Patent Document 2). However, since this method uses a glass cap, it cannot cope with a flexible device. Further, since the hygroscopic material is opaque, this method cannot be adopted in the case of the top emission method in which light is emitted from the side opposite to the substrate side.

Japanese Patent No. 4070505 Japanese Patent No. 4766628

  Therefore, the present invention improves the stability of initial light emission even when an insulating smoothing layer is provided when a conductive base material such as metal is used as a substrate, and deteriorates in a high-temperature and high-humidity environment. An object of the present invention is to provide an organic EL device and a method for manufacturing the same.

The organic EL device of the present invention is an organic EL device having a conductive substrate,
Having an insulating smooth layer on the conductive substrate;
A gas barrier layer on the insulating smooth layer;
An organic EL element on the gas barrier layer;
The gas barrier layer includes at least one of a metal and a metalloid;
The gas barrier layer includes a discharge treatment layer subjected to a discharge treatment and a non-discharge treatment layer not subjected to a discharge treatment.

The organic EL device manufacturing method of the present invention is a method of manufacturing an organic EL device in which a gas barrier layer is formed on an insulating smooth layer formed on a conductive substrate, and an organic EL element is formed on the gas barrier layer. There,
A gas barrier layer forming step of forming a gas barrier layer containing at least one selected from metals and metalloids;
A discharge treatment step in which a part of the gas barrier layer is treated as a discharge treatment layer and another part not subjected to the discharge treatment is treated as a non-discharge treatment layer by performing a discharge treatment on a part of the gas barrier layer. It is characterized by.

  According to the present invention, even when an insulating smooth layer is provided when a conductive base material such as metal is used as a substrate, the stability of the initial light emission is improved and the deterioration under a high-temperature and high-humidity environment is achieved. It is possible to provide an organic EL device and a method for manufacturing the same.

FIG. 1 is a schematic cross-sectional view showing an example of the configuration of the organic EL device of the present invention. FIG. 2 is a schematic cross-sectional view showing a modification of the configuration of the organic EL device of the present invention. FIG. 3 is a schematic cross-sectional view showing another example of the configuration of the organic EL device of the present invention. FIG. 4 is a schematic diagram showing an example of the configuration of an apparatus for manufacturing the organic EL device of the present invention by a batch production method. FIG. 5 is a schematic diagram showing an example of the configuration of an apparatus for manufacturing the organic EL device of the present invention by a continuous production method. FIG. 6 is a photograph of the initial state and 7 days after the organic EL device of Example 1 and Comparative Example 1 was caused to emit light.

  In the organic EL device of the present invention, the ratio (Y / X) of the density (Y) of the discharge treatment layer to the density (X) of the non-discharge treatment layer is in the range of more than 1.0 and not more than 2.0. It is preferable.

  In the organic EL device of the present invention, the ratio (y / x) of the thickness (y) of the discharge treatment layer to the thickness (x) of the gas barrier layer is preferably in the range of 0.05 to 0.3.

In the organic EL device of the present invention, the gas barrier layer is formed in the order of the non-discharge treatment layer and the discharge treatment layer from the insulating smooth layer side,
It is preferable that a barrier layer is further formed on the discharge treatment layer of the gas barrier layer.

  In the organic EL device of the present invention, at least one of the metal and the metalloid is at least one selected from the group consisting of oxide, nitride, carbide, oxynitride, oxycarbide, nitrided carbide, and oxynitride carbide. It is preferable that

  In the manufacturing method of the organic EL device of the present invention, it is preferable that a part of the gas barrier layer is a surface layer portion of the gas barrier layer.

  In the method for manufacturing an organic EL device according to the present invention, the discharge treatment is preferably performed by plasma beam irradiation or ion beam irradiation.

  The organic EL device according to another aspect of the present invention is preferably manufactured by the method for manufacturing an organic EL device of the present invention.

  Next, the present invention will be described in detail. However, the present invention is not limited by the following description.

  The organic EL element has a laminate in which an anode, an organic EL layer, and a cathode are provided in this order on a substrate. As the anode, for example, an ITO (Indium Tin Oxide) or IZO (registered trademark, Indium Zinc Oxide) layer that can be used as a transparent electrode layer is formed. The organic EL layer includes, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. As the cathode, an aluminum layer, a magnesium / aluminum layer, a magnesium / silver layer, or the like is also formed as a reflective layer. Sealing is performed from above so that the laminated body is not exposed to the atmosphere.

  The organic EL device in the present invention uses a conductive substrate as the substrate. The formation surface of the organic EL element needs to ensure insulation. Therefore, when using a conductive substrate, it is necessary to provide an insulating smooth layer on the conductive substrate. In the present invention, an organic EL element is formed on a conductive substrate having a gas barrier layer on the insulating smooth layer. If a metal foil is used as the substrate, the organic EL element can be reduced in weight, thickness, and flexibility. In this case, the organic EL device as a display becomes flexible and can be used like electronic paper by rolling it.

  As the insulating smooth layer in the present invention, an insulating resin layer can be used. Examples of the resin include acrylic, norbornene, epoxy, polyimide, polyester, polyarylate, polyurethane, polycarbonate, polyetherketone, polyphenylsulfone, and the like.

  If the thickness of the insulating smooth layer is too thin, the surface unevenness of the conductive substrate cannot be sufficiently flattened, and if it is too thick, the effect of water vapor transmission may be exerted on the organic EL element. Therefore, the thickness of the insulating smooth layer is preferably in the range of 0.1 to 20 μm, more preferably in the range of 0.5 to 10 μm, and still more preferably in the range of 1 to 5 μm. In the said range, the thickness of the said insulating smooth layer has the range of the more preferable thickness according to the magnitude | size of the surface unevenness | corrugation of the said electroconductive board | substrate.

  The gas barrier layer in the organic EL device of the present invention includes a discharge treatment layer that has been subjected to a discharge treatment and a non-discharge treatment layer that has not been subjected to a discharge treatment.

  The discharge treatment layer and the non-discharge treatment layer contain at least one of a metal and a semimetal. At least one of the metal and the metalloid is preferably at least one selected from the group consisting of oxides, nitrides, carbides, oxynitrides, oxycarbides, nitride carbides, and oxynitride carbides. Examples of the metal include aluminum, titanium, indium, and magnesium. Examples of the metalloid include silicon, bismuth, and germanium. In order to improve the gas barrier property, it is preferable to contain carbon and nitrogen that make the network structure (network structure) in the gas barrier layer dense. Furthermore, in order to improve transparency, it is preferable to contain oxygen.

  The gas barrier layer is formed by a dry process using a vacuum such as vapor deposition, sputtering, or chemical vapor deposition (CVD). Thereby, a very dense thin film having a high gas barrier property can be obtained. Among these, a vapor deposition method is preferable. This is because the vapor deposition method is a process with a very high film formation rate and is a highly productive process, and thus has high production efficiency.

  In the organic EL device of the present invention, the discharge treatment layer is formed by subjecting a part of the gas barrier layer to a discharge treatment. The other part that is not subjected to the discharge treatment is a non-discharge treatment layer. The discharge treatment layer has a higher layer density than the non-discharge treatment layer and has excellent gas barrier properties. It is preferable that a part of the gas barrier layer is a surface layer portion of the gas barrier layer. Since the discharge treatment layer is a layer formed by surface treatment, the layer thickness is thin and the transparency is high. The thickness of the layer varies depending on conditions such as discharge output and processing time, but can be in the range of 2.5 nm to 150 nm, and preferably in the range of 7.5 nm to 105 nm. Examples of the discharge treatment include irradiation with an ionizing active gas such as corona discharge, atmospheric pressure plasma, high frequency plasma, direct current plasma, arc discharge plasma, and ion beam. Among these, arc discharge plasma and ion beam are preferable, and arc discharge plasma is more preferable. Arc discharge plasma has been found to have a very high electron density, unlike normally used glow discharge plasma. By using arc discharge plasma for the vapor deposition method, the reactivity can be increased and a very dense gas barrier layer can be formed.

  The arc discharge plasma can be formed by, for example, a pressure gradient type plasma gun, a direct current discharge plasma generator, a high frequency discharge plasma generator, etc., and the pressure capable of generating a high-density plasma stably even during vapor deposition. It is preferable to use a gradient plasma gun.

  In the discharge treatment, it is preferable to introduce a gas. The gas is not particularly limited, and examples thereof include inert gases such as helium, neon, argon, and xenon, and reactive gases such as oxygen, nitrogen, hydrogen, and hydrocarbons.

The density (Y) of the discharge treatment layer is higher than the density (X) of the non-discharge treatment layer, and the ratio of the density (Y) of the discharge treatment layer to the density (X) of the non-discharge treatment layer (Y / X) is in the range of more than 1.0 and not more than 2.0. Due to the presence of the high density discharge treatment layer, the gas barrier property can be improved even if the gas barrier layer is thin. However, if the density ratio is greater than 2.0 or less than 1.0, an internal stress difference is generated, cracks are generated, and the gas barrier property is decreased. The density ratio is preferably in the range of 1.2 to 1.8, and more preferably in the range of 1.5 to 1.8. The density of the non-discharge treated layer varies depending on the material, composition, and film forming method. For example, the silicon oxide layer is 1.6 to 2.2 g · cm ⁻³ , and the silicon nitride layer is 2.3 to 2 0.7 g · cm ⁻³ .

  The discharge treatment layer is formed on a part of the gas barrier layer, and a ratio (y / x) of the thickness (y) of the discharge treatment layer to the thickness (x) of the gas barrier layer is 0.05 to 0.3. It is a range. When the thickness ratio is less than 0.05, the gas barrier property is lowered, which is not preferable. On the other hand, when the ratio is larger than 0.3, the production efficiency is lowered due to the processing time. The thickness ratio is preferably in the range of 0.07 to 0.25, and more preferably in the range of 0.13 to 0.25.

  The thickness of the gas barrier layer is preferably in the range of 50 to 2000 nm in consideration of gas barrier properties, film formation time, and internal stress of the film. More preferably, it is the range of 150 nm-1000 nm.

  FIG. 1 is a schematic cross-sectional view of an example of the configuration of the organic EL device of the present invention. As illustrated, the organic EL device 100 includes a gas barrier layer 120 on an insulating smooth layer 102 formed on a conductive substrate 101, and an organic EL element 110 on the gas barrier layer 120. In the figure, the organic EL element is surface-sealed with a sealing layer 150 and a sealing plate 160, but is not limited thereto. The organic EL element 110 emits light using the excitation energy generated by the combination of electrons and holes in the organic EL layer 112 by an externally supplied current through the anode 111 and the cathode 113. In the present invention, light from the organic EL layer 112 is emitted from the cathode 113 side of the organic EL element 110 (top emission method). In the gas barrier layer 120, a non-discharge treated layer 120a that has not been subjected to a discharge treatment and a discharge treatment layer 120b that has been subjected to a discharge treatment are formed on the insulating smoothing layer 102 in this order. FIG. 3 is a schematic cross-sectional view of another example of the configuration of the organic EL device of the present invention. In the organic EL device 200, a gas barrier layer 220 is formed on the insulating smooth layer 102, and a barrier layer 230 is further formed on the gas barrier layer 220. In the gas barrier layer 220, a non-discharge treatment layer 220a and a discharge treatment layer 220b are formed on the insulating smoothing layer 102 in this order. The barrier layer 230 preferably contains at least one of the same metal and semimetal as the gas barrier layer, and can be formed in the same manner as the gas barrier layer and the non-discharge treatment layer in the gas barrier layer.

  As the sealing layer 160, a material having excellent water resistance and heat resistance and low moisture permeability can be used. Examples of such a material include epoxy, acrylic, polyester, polyarylate, and polyurethane. The use of a two-component curable epoxy resin is preferable because it can be cured at room temperature and does not require heating of the organic EL element, thereby preventing deterioration. As the sealing plate 160, it is preferable to use a material having a low moisture permeability such as a resin film on which a glass plate and a gas barrier layer are formed.

  As a sealing method, as in the organic EL device 100 </ b> A illustrated in FIG. 2, a sealing material 170 such as a glass cap may be used, and the periphery thereof may be hollow sealed with an adhesive 180. In FIG. 2, the same parts as those in FIG. As the adhesive 180 used for the sealing, the same material as the sealing layer 160 described above can be used.

  In the gas barrier layer, the number and order of formation of the non-discharge treatment layers and the discharge treatment layers are not particularly limited as long as at least one of the layers is formed. The order of the formation can be, for example, the order of non-discharge treatment layer / discharge treatment layer, or the order of non-discharge treatment layer / non-discharge treatment layer / discharge treatment layer. It is preferable to form a non-discharge treatment layer as a barrier layer because gas barrier properties can be effectively expressed.

  In the present invention, when at least one of the metal and the metalloid is selected from the group consisting of oxide, nitride, carbide, oxynitride, oxycarbide, nitrided carbide, and oxynitride carbide, oxide, nitride Oxygen, carbon, or nitrogen contained in carbide, oxynitride, oxycarbide, nitride carbide, oxynitride carbide, for example, generates an arc discharge plasma in the presence of a reaction gas, so that at least the metal and the semimetal It can introduce | transduce by performing 1 type of vapor deposition. A metal oxide or a semi-metal oxide can also be used as a vapor deposition material in the vapor deposition. As the reaction gas, an oxygen-containing gas, a nitrogen-containing gas, a hydrocarbon-containing gas, or a mixed gas thereof can be used.

The oxygen-containing gas is oxygen (O ₂ ), dinitrogen monoxide (N ₂ O), nitric oxide (NO), and the nitrogen-containing gas is nitrogen (N ₂ ), ammonia (NH ₃ ), nitrogen monoxide (NO ), Hydrocarbon-containing gases include methane (CH ₄ ), ethane (C ₂ H ₆ ), propane (C ₃ H ₈ ), butane (C ₄ H ₁₀ ), ethylene (C ₂ H ₄ ), acetylene (C ₂ ). H ₂ ).

  As a means for evaporating the vapor deposition material, a method of introducing any one of resistance heating, electron beam, and arc discharge plasma into the vapor deposition material (deposition source) can be used. Among these methods, a method using an electron beam or arc discharge plasma capable of high-speed vapor deposition is preferable. These methods may be used in combination.

  The organic EL device can be manufactured by either a batch production method or a continuous production method. In the case of the continuous production method, for example, a metal foil in which an insulating smooth layer is previously formed is used as a substrate, and the metal foil is continuously conveyed by a roll in a vacuum chamber when the gas barrier layer and the organic EL element are formed. The gas barrier layer and the organic EL element are formed on the metal foil (Roll-to-roll method).

  In FIG. 4, an example of a structure of the apparatus which manufactures the gas barrier layer of the organic EL device in this invention by a batch production system is shown. As shown, the manufacturing apparatus 300 mainly includes a vacuum chamber 1, a pressure gradient plasma gun 2, a reflective electrode 5, a focusing electrode 6, a vapor deposition source 7, a discharge gas supply unit 11, a reaction gas supply unit 12, and a vacuum pump 20. As a component. A substrate heater 13 is disposed in the vacuum chamber 1, and a substrate 3 on which an insulating smooth layer is formed is installed on the substrate heater 13. The vapor deposition source 7 is installed at the bottom of the vacuum chamber 1 so as to face the substrate heater 13. A vapor deposition material 8 is mounted on the upper surface of the vapor deposition source 7. The vacuum pump 20 is disposed on the side wall (right side wall in the figure) of the vacuum chamber 1, whereby the inside of the vacuum chamber 1 can be decompressed. The discharge gas supply means 11 and the reaction gas supply means 12 are arranged on the side wall (right side wall in the figure) of the vacuum chamber 1. The discharge gas supply means 11 is connected to a discharge gas gas cylinder 21, whereby a discharge gas (for example, argon gas) having an appropriate pressure can be supplied into the vacuum chamber 1. Yes. The reaction gas supply means 12 is connected to a reaction gas gas cylinder 22, and thereby supplies a reaction gas (for example, oxygen gas, nitrogen gas, methane gas) having an appropriate pressure into the vacuum chamber 1. Is possible. A temperature control means (not shown) is connected to the substrate heater 13. Thereby, the temperature of the substrate 3 can be set within a predetermined range by adjusting the surface temperature of the substrate heater 13. Examples of the temperature control means include a heat medium circulation device that circulates silicone oil and the like.

An example of the manufacturing process of the gas barrier layer when the manufacturing apparatus shown in FIG. 4 is used is as follows. After evacuating the inside of the vacuum chamber 1 to 10 ⁻³ Pa or less, argon is introduced as a discharge gas from the discharge gas supply means 11 into the pressure gradient plasma gun 2 which is an arc discharge plasma generation source, and a constant voltage is applied. Then, the plasma beam 4 is irradiated toward the reflective electrode 5 so that the insulating smooth layer formed on the substrate 3 is exposed. The plasma beam 4 is controlled by the focusing electrode 6 so as to have a constant shape. The output of the arc discharge plasma is, for example, 1 to 10 kW. On the other hand, the reaction gas is introduced from the reaction gas supply means 12. Further, the vapor deposition material 8 installed in the vapor deposition source 7 is irradiated with an electron beam 9 to evaporate the material toward the insulating smooth layer. In the presence of the reaction gas, vapor deposition is performed to form a predetermined gas barrier layer on the insulating smooth layer. The gas barrier layer formation rate (vapor deposition rate) is measured and controlled by a crystal monitor 10 installed in the vicinity of the substrate 3. During the period from the start of evaporation until the deposition rate is stabilized, a shutter (not shown) covering the substrate 3 is closed, and after the deposition rate is stabilized, the shutter is opened to form the gas barrier layer. preferable. When a plurality of layers are stacked as the gas barrier layer, this step is repeated to form a predetermined stacked body. When the discharge treatment layer is formed, the vapor deposition material 8 installed in the vapor deposition source 7 is not irradiated with the electron beam, but only the arc discharge plasma is irradiated onto the substrate 3 (insulating smooth layer). The output of the arc discharge plasma at this time is the same as described above. By controlling the output of the discharge plasma and the irradiation time, the density and thickness of the discharge treatment layer can be controlled. When the discharge plasma is set to a high output, the discharge treatment layer can be made dense, and when the irradiation time is made long, the thickness of the discharge treatment layer can be increased. The system pressure at the time of forming each layer is, for example, in the range of 0.01 Pa to 0.1 Pa, and preferably in the range of 0.02 Pa to 0.05 Pa. The substrate temperature is, for example, in the range of 20 ° C to 200 ° C, and preferably in the range of 80 ° C to 150 ° C. The generation of the arc discharge plasma and the introduction of the reaction gas may be performed simultaneously or before and after, the reaction gas introduction and the plasma generation may be performed simultaneously, or the plasma may be generated after the reaction gas introduction, A reactive gas may be introduced after the plasma generation. The reaction gas may be present in the system when the gas barrier layer is formed.

  In FIG. 5, an example of a structure of the apparatus which manufactures the gas barrier layer in the organic EL device of this invention by a continuous production system is shown. The continuous production method is a method in which the gas barrier layer is formed on the insulating smooth layer while continuously transporting the metal foil on which the insulating smooth layer is formed by a roll in a vacuum chamber when the gas barrier layer is formed. is there. In FIG. 5, the same parts as those in FIG. As shown in the drawing, in this manufacturing apparatus 400, in place of the substrate heater 13, an unwinding roll 33a, a can roll 35, a winding roll 33b, and two auxiliary rolls 34a and 34b are arranged in the vacuum chamber 31. Yes. The metal foil 32 is stretched over the can roll 35 and the two auxiliary rolls 34a and 34b from the unwind roll 33a to the take-up roll 33b. Except for these, the configuration is the same as in FIG. A temperature control means (not shown) is connected to the can roll 35. Examples of the temperature control means are the same as those for the substrate heater 13.

  In continuous production using this device, film-like conductive substrates such as metal foil are continuously introduced into the device, and the conductive substrate is moved while being exposed to an arc discharge plasma beam in the presence of a reactive gas. And continuously forming a gas barrier layer. A predetermined laminate can be formed by switching this reaction gas and target and repeating this process without irradiating the vapor deposition material with an electron beam. Continuous production by this apparatus can be carried out in the same manner as an apparatus manufactured by a batch production method, except that vapor deposition and discharge treatment are performed while moving the conductive substrate.

  Next, examples of the present invention will be described together with comparative examples. The present invention is not limited or restricted by the following examples and comparative examples. In addition, various properties and physical properties in each example and each comparative example were measured and evaluated by the following methods.

(Thickness of each layer constituting the gas barrier layer)
The thickness d of each layer constituting the gas barrier layer is determined by observing the cross section of the organic EL device with a scanning electron microscope (trade name: JSM-6610) manufactured by JEOL Ltd., and from the surface of the insulating smooth layer to the surface of each layer. The length was measured and calculated.

(Density of each layer constituting the gas barrier layer)
The density ρ of each layer constituting the gas barrier layer was determined by measuring the X-ray reflectivity of each layer constituting the gas barrier layer using an X-ray diffractometer (trade name: Smart Lab) manufactured by Rigaku Corporation, and calculating the density of each layer. .

(Water vapor transmission rate)
The water vapor transmission rate (WVTR) is the same as the substrate sealing layer formed in the examples and comparative examples, but is made of a transparent resin film (polyethylene naphthalate film (thickness 100 μm, trade name “Teonex”) manufactured by Teijin DuPont Films) It was set as the value measured about what was formed in. The water vapor transmission rate (WVTR) was measured in a water vapor transmission rate measurement device (manufactured by MOCON, trade name PERMATRAN) specified in JIS K7126 under an environment of a temperature of 40 ° C. and a humidity of 90% RH. In addition, the measurement range of the said water-vapor-permeability measuring apparatus is 0.005g * m ^<-2 > * day ^{< -1} > or more.

(Initial brightness)
The organic EL devices immediately after fabrication were each driven with a constant voltage of 6 V, and the luminance was measured. The luminance was measured using a luminance orientation characteristic measuring device (trade name: C9920-11) manufactured by Hamamatsu Photonics Co., Ltd.

(Light emission area after 7 days)
The organic EL device after the initial luminance measurement was stored in a non-lighted state under a constant temperature and humidity condition of a temperature of 23 ° C. and a humidity of 40%. Seven days later, the organic EL device was caused to emit light, and the light emission area in the microscopic observation was measured. Observation and light emission area measurement were performed using a digital microscope (trade name: VHX-1000) manufactured by Keyence Corporation.

[Example 1]
[Production of insulating smooth layer]
A stainless steel (SUS) substrate was prepared as a conductive substrate for producing an organic EL element (SUS304, thickness 50 μm). An acrylic resin (trade name “JEM-477” manufactured by JSR Corporation) is applied on the SUS substrate, dried at 80 ° C. for 5 minutes, cured at 100 ° C. for 1 hour, and an insulating smooth layer having a thickness of 3 μm is formed. Produced.

[Production of gas barrier layer]
Next, the SUS substrate coated with the insulating smooth layer was mounted on a manufacturing apparatus shown in FIG. Argon gas 20 sccm (20 × 1.69 × 10 ⁻³ Pa · m ³ / sec) was introduced into the pressure gradient plasma gun, and a discharge output of 5 kW was applied to the plasma gun to generate arc discharge plasma. As a reaction gas, nitrogen (purity 5N: 99.999%) was introduced into the vacuum chamber at a flow rate of 40 sccm (40 × 1.69 × 10 ⁻³ Pa · m ³ / sec). A silicon grain (purity 3N: 99.9%) is irradiated with an electron beam (acceleration voltage 6 kV, applied current 50 mA) and evaporated to a deposition rate of 100 nm / min, and a gas barrier layer is formed on the insulating smooth layer. Was deposited to a thickness of 80 nm. At this time, the system internal pressure was 2.0 × 10 ⁻² Pa, and the substrate heater temperature was 100 ° C.

[Discharge treatment]
Thereafter, the irradiation of the electron beam was stopped, and the evaporation of the silicon grains was stopped. In this state, argon gas was vacuumed at a flow rate of 20 sccm (20 × 1.69 × 10 ⁻³ Pa · m ³ / sec) and nitrogen at a flow rate of 40 sccm (40 × 1.69 × 10 ⁻³ Pa · m ³ / sec). It was introduced into the tank, a discharge output of 5 kW was applied to the plasma gun, and the gas barrier layer was irradiated with arc discharge plasma for 30 seconds to form a discharge treatment layer.

About the obtained gas barrier layer, the thickness and density of each layer were analyzed. The thickness (x) of the gas barrier layer was 80 nm, and the density (X) was 2.4 g · cm ⁻³ . The thickness (y) of the discharge treatment layer was 10 nm, and the density (Y) was 3.6 g · cm ⁻³ . The ratio of the density of the discharge treatment layer to the density of the non-discharge treatment layer (Y / X) is 1.5, and the ratio of the thickness of the discharge treatment layer to the thickness of the gas barrier layer (y / x) is 0.125. is there.

[Production of organic EL elements]
On the obtained gas barrier layer, 100 nm of Al is used as an anode by vacuum evaporation, HAT-CN (manufactured by Wako Pure Chemical Industries, Ltd.) is 10 nm as a hole injection layer, and NPB (N, N′-bis ( Naphthalen-1-yl) -N, N′-bis (phenyl) -benzidine) is 50 nm, Alq (tris (8-quinolinolato) aluminum) is 45 nm as a light emitting layer and an electron transport layer, and LiF is 0. 5 nm, 5/15 nm (co-evaporation) of Mg / Ag as a cathode, and 60 nm of MoO ₃ as a refractive index adjusting layer were vapor-deposited in this order, and an organic EL device was produced.

[Sealing]
After forming the organic EL element, sealing is performed by providing a glass cap so that the terminal can be connected from the anode and the cathode while covering the light-emitting layer. Got. The adhesive around the glass cap was coated with an adhesive containing a two-component curable epoxy resin (trade name “Bond Quick 5” manufactured by Konishi Co., Ltd.), and the adhesive was naturally cured and sealed.

[Example 2]
Except that an acrylic resin (trade name “JEM-477” manufactured by JSR Corporation) was applied on the SUS substrate and an insulating smooth layer having a thickness of 15 μm was produced, the same as in Example 1 was repeated. An organic EL device was obtained.

[Example 3]
A norbornene resin (trade name “Zeocoat” manufactured by Nippon Zeon Co., Ltd.) is applied on the SUS substrate, dried at 80 ° C. for 5 minutes, and then cured at 100 ° C. for 1 hour to produce an insulating smooth layer having a thickness of 3 μm. Except having done, it carried out similarly to Example 1, and obtained the organic EL device of the present Example.

[Example 4]
A norbornene resin (trade name “Zeocoat” manufactured by Nippon Zeon Co., Ltd.) is applied on the SUS substrate, dried at 80 ° C. for 5 minutes, and then cured at 100 ° C. for 1 hour to produce an insulating smooth layer having a thickness of 15 μm. Except having done, it carried out similarly to Example 3, and obtained the organic EL device of the present Example.

[Example 5]
Until the non-discharge treatment layer and the discharge treatment layer are formed, a barrier layer is formed on the discharge treatment layer under the same conditions as in the gas barrier layer formation step. An EL device was obtained. When the thickness and density of the obtained gas barrier layer were analyzed, it was the same as in Example 1.

[Example 6]
Until the non-discharge treatment layer and the discharge treatment layer are formed, a barrier layer is formed on the discharge treatment layer under the same conditions as in the gas barrier layer formation step. An EL device was obtained.

[Example 7]
Until the non-discharge treatment layer and the discharge treatment layer are formed, a barrier layer is formed on the discharge treatment layer under the same conditions as in the gas barrier layer formation step. An EL device was obtained.

[Example 8]
Until the non-discharge treatment layer and the discharge treatment layer are formed, a barrier layer is formed on the discharge treatment layer under the same conditions as in the gas barrier layer formation step. An EL device was obtained.

[Comparative Example 1]
An organic EL device of this comparative example was obtained in the same manner as in Example 1 except that the gas barrier layer was not formed.

[Comparative Example 2]
An organic EL device of this comparative example was obtained in the same manner as in Example 2 except that the gas barrier layer was not formed.

[Comparative Example 3]
An organic EL device of this comparative example was obtained in the same manner as in Example 3 except that the gas barrier layer was not formed.

[Comparative Example 4]
An organic EL device of this comparative example was obtained in the same manner as in Example 4 except that the gas barrier layer was not formed.

[Comparative Example 5]
An insulating smooth layer was prepared in the same manner as in Example 1, a non-discharge treated layer was formed under the same conditions as in Example 1, and a barrier layer was formed thereon under the same conditions as in the non-discharge treated layer. Other than that was carried out similarly to Example 1, and obtained the organic EL device of this comparative example.

[Comparative Example 6]
An insulating smooth layer was produced in the same manner as in Example 2, a non-discharge treated layer was formed under the same conditions as in Example 1, and a barrier layer was formed thereon under the same conditions as in the non-discharge treated layer. Other than that was carried out similarly to Example 1, and obtained the organic EL device of this comparative example.

[Comparative Example 7]
An insulating smooth layer was produced in the same manner as in Example 3, a non-discharge treated layer was formed under the same conditions as in Example 1, and a barrier layer was formed thereon under the same conditions as in the non-discharge treated layer. Other than that was carried out similarly to Example 1, and obtained the organic EL device of this comparative example.

[Comparative Example 8]
An insulating smooth layer was produced in the same manner as in Example 4, a non-discharge treated layer was formed under the same conditions as in Example 1, and a barrier layer was formed thereon under the same conditions as in the non-discharge treated layer. Other than that was carried out similarly to Example 1, and obtained the organic EL device of this comparative example.

[Reference example]
Example 1 except that an organic EL element was directly formed on an alkali-free glass substrate (manufactured by Matsunami Glass Industry Co., Ltd., product number: AF-45, thickness: 700 μm) without forming an insulating smooth layer and a gas barrier layer. In the same manner, an organic EL device of this reference example was obtained.

For the organic EL devices obtained in Examples 1 to 8, Comparative Examples 1 to 8, and Reference Example, the water vapor transmission rate (WVTR), initial luminance, and light emitting area of the sealing layer (transparent gas barrier layer and barrier layer) were measured. did. The measurement results are shown in Table 1. In addition, FIG. 6 shows photographs of the initial state and seven days after the organic EL devices of Example 1 and Comparative Example 1 emitted light.

As shown in Table 1, in the organic EL devices obtained in the examples, the water vapor transmission rate of the substrate sealing layer (gas barrier layer, gas barrier layer and barrier layer) was 0.01 g · m ⁻² · day. ^-1 or less and good gas barrier properties. For this reason, it is possible to prevent the permeation of moisture from the substrate side, and to obtain an organic EL device having a favorable initial property that has a high initial luminance and a small reduction rate of the light emitting area after 7 days and has a suitable deterioration prevention characteristic I understand. It can be said that these characteristics are almost equivalent to those of the organic EL device of the reference example, which was produced without providing the insulating smooth layer on the glass substrate. On the other hand, in Comparative Examples 5 to 8 having no discharge treatment layer, the water vapor transmission rate was as high as 0.2 g · m ⁻² · day ⁻¹ and the gas barrier properties were inferior. Therefore, it can be seen that the emission area after 7 days of the organic EL device is greatly reduced, and only a slight improvement is made as compared with Comparative Examples 1 to 4 in which the substrate sealing layer was not formed. As shown in FIG. 6, in the organic EL device of Comparative Example 1, many black spots that did not emit light were observed even in the initial stage (immediately after fabrication). Comparing the examples and the comparative examples, it can be seen that the formation of the discharge treatment layer can prevent the deterioration of the organic EL element over time while suppressing the deterioration of the light emitting layer in the initial stage. In the above, the example in which the thickness of the insulating smooth layer was 3 μm resulted in better initial luminance and light emitting area than the example in which the thickness of the insulating smooth layer was 15 μm. This is considered to be due to the fact that when the insulating smooth layer (organic material) is thick, water, gas, and the like are generated from the organic material due to heat applied during the formation of the organic EL element and heat generated during driving. In this example and comparative example, in order to see the influence of moisture from the substrate side, glass cap sealing is performed. In the present invention, in addition to glass cap sealing, a sealing adhesive ( Good effects can also be obtained as surface sealing using a sealing layer) and a sealing plate.

  The organic EL device of the present invention improves the stability of the initial light emission of the organic EL element even when an insulating smooth layer is provided when a conductive base material such as metal is used as a substrate, and is high temperature and high humidity. The deterioration under the environment can be prevented, and the life of the organic EL element can be extended. Therefore, according to the present invention, it is possible to improve the luminance, lifetime and reliability of the organic EL device. Since the organic EL device of the present invention can use a conductive base material such as a metal foil for flexible devices as a substrate, it can be used in various fields such as lighting devices and display devices. It is not limited.

100, 100A, 200 Organic EL (electroluminescence) device 101 Conductive substrate 102 Insulating smooth layer 110 Organic EL (electroluminescence) element 111 Anode 112 Organic EL (electroluminescence) layer 113 Cathode 120, 220 Gas barrier layer 120a, 220a Non-discharge Treatment layer 120b, 220b Discharge treatment layer 150 Sealing layer 160 Sealing plate 170 Sealing material (glass cap)
180 Adhesive 230 Barrier layer 300, 400 Manufacturing apparatus 1, 31 Vacuum chamber 2 Pressure gradient type plasma gun (arc discharge plasma generation source)
3 Substrate 4 Plasma beam 5 Reflective electrode 6 Focusing electrode 7 Evaporation source 8 Evaporation material 9 Electron beam 10 Crystal monitor 11 Discharge gas supply means 12 Reaction gas supply means 13 Substrate heater 20 Vacuum pump 21 Gas cylinder for discharge gas 22 Gas cylinder for reaction gas 32 Metal foil 33a Unwinding roll 33b Winding rolls 34a, 34b Auxiliary roll 35 Can roll

Claims (8)

An organic EL device having a conductive substrate,
Having an insulating smooth layer on the conductive substrate;
A gas barrier layer on the insulating smooth layer;
An organic EL element on the gas barrier layer;
The gas barrier layer includes at least one of a metal and a metalloid;
The organic EL device, wherein the gas barrier layer includes a discharge treatment layer subjected to a discharge treatment and a non-discharge treatment layer not subjected to a discharge treatment. The ratio (Y / X) of the density (Y) of the discharge treatment layer to the density (X) of the non-discharge treatment layer is in the range of more than 1.0 and 2.0 or less. 1. The organic EL device according to 1. The ratio (y / x) of the thickness (y) of the discharge treatment layer to the thickness (x) of the gas barrier layer is in the range of 0.05 to 0.3. Organic EL device. The gas barrier layer is formed in the order of the non-discharge treatment layer and the discharge treatment layer from the insulating smooth layer side,
The organic EL device according to any one of claims 1 to 3, wherein a barrier layer is further formed on the discharge treatment layer of the gas barrier layer. At least one of the metal and the metalloid is at least one selected from the group consisting of oxide, nitride, carbide, oxynitride, oxycarbide, nitride carbide, and oxynitride carbide, The organic EL device according to any one of claims 1 to 4. A method for producing an organic EL device comprising: forming a gas barrier layer on an insulating smooth layer formed on a conductive substrate; and forming an organic EL element on the gas barrier layer,
A gas barrier layer forming step of forming a gas barrier layer containing at least one selected from metals and metalloids;
A discharge treatment step in which a part of the gas barrier layer is treated as a discharge treatment layer and another part not subjected to the discharge treatment is treated as a non-discharge treatment layer by performing a discharge treatment on a part of the gas barrier layer. A method for producing an organic EL device, comprising: The method of manufacturing an organic EL device according to claim 6, wherein a part of the gas barrier layer is a surface layer portion of the gas barrier layer. 8. The method of manufacturing an organic EL device according to claim 6, wherein the discharge treatment is performed by plasma beam irradiation or ion beam irradiation.