KR101177064B1 - OLED with enhanced light extraction efficiency - Google Patents

Abstract

The present invention relates to an organic light emitting device, and more particularly to a support substrate; An organic light emitting unit formed on one surface of the support substrate and including an organic light emitting layer between a pair of electrodes; An encapsulation substrate positioned above the organic light emitting part; And an encapsulant that couples the support substrate and the encapsulation substrate, wherein an inner surface of the encapsulation substrate is formed of a hygroscopic filler including metal nanoparticles, wherein the light extraction efficiency is improved. to provide.

Description

Organic light emitting device with improved light extraction efficiency

The present invention relates to an organic EL device, and more particularly, to an organic EL device having improved light extraction efficiency using a hygroscopic filler.

In the organic light emitting device, the organic light emitting unit is generally injected by injecting electrons and holes into the light emitting layer from the electron injection electrode and the hole injection electrode, respectively. It is a device that emits light when an exciton in which electrons and holes are combined falls from an excited state to a ground state.

Due to this principle, unlike the conventional thin film liquid crystal display device, since a separate light source is not required, there is an advantage in that the volume and weight of the device can be reduced.

In addition, the organic EL device exhibits high quality panel characteristics (low power, high brightness, high reaction rate, low weight). OELD is considered to be a powerful next-generation display that can be applied to portable communication products such as mobile communication terminal, CNS (Car Navigation System), personal digital assistances (PDA), Palm PC, etc.

In general, the organic light emitting device is composed of a transparent support substrate and a sealing substrate spaced apart from each other, the support substrate and the sealing substrate is encapsulated with each other by a sealing material (encapsulation). An array portion including a plurality of thin film transistors, gates, data lines, and storage capacitors is formed on an upper portion of the support substrate. have. In this case, the organic layer expresses the colors of red (R), green (G), and blue (B), and in general, red (R), green (G), and blue (B) colors for each pixel. A separate organic material emitting light is used as a pattern.

Since the organic light emitting device (OLED) is a self-luminous type, the viewing angle is wider than the LCD, the contrast is good, and since the backlight is not required, the organic light emitting device (OLED) can be reduced in weight and advantageous in terms of power consumption. In addition, it is easy to display video because it has a sensitive screen and quick response time compared to other displays, and unlike LCD, it is attracting attention as a next-generation display because it is composed of solid thin film, which is strong in vibration and has a relatively wide use temperature range.

The display substrate utilized in the organic EL device is important for gas permeability such as oxygen or moisture through the substrate represented by gas barrier properties. This is because the durability of the material constituting the display element is affected by the transmitted oxygen or moisture, and since the material of the light emitting layer reacts very sensitively to oxygen or moisture and deteriorates, organic electroluminescence is emitted by these intrusions. There is a problem in that the performance of the device is degraded and the lifespan is shortened so that the luminous efficiency sharply decreases.

In addition, there are various factors related to the light emission life, but it is known that when a higher voltage is applied to the device in order to increase the light emission luminance, the life is shorter. However, the light emission luminance of the display using the organic light emitting element is not satisfactory in the state of applying low voltage, and in order to secure the visibility of the display outdoors in daylight, it is necessary to increase the light emission luminance by applying a high voltage to the element. As described above, the organic light emitting device has a problem in that light emission luminance must be weakened to increase the lifespan, and life span is shortened to increase visibility.

In order to solve this problem, the improvement of the light emitting layer material of the organic light emitting device has been actively progressed, that is, a study for improving the light extraction efficiency has been conducted in order to realize high light emission luminance by applying a lower voltage. .

The light extraction efficiency refers to the ratio of light emitted from the front of the transparent substrate to the light emission of the light emitting layer. The light extraction efficiency must pass through the interface of the medium having different refractive indices until the light emitted from the light emitting layer is emitted into the atmosphere. Light incident at an angle is totally reflected at the interface, waveguides into the layer, is lost, or is emitted from the side of the layer, thereby reducing the emission of light at the front. The light emitted to the front is only about 20% of the light emitted from the light emitting layer.

Therefore, various attempts have been made in the past to solve such a problem. In Japanese Laid-Open Patent Publication No. 61-156691, a method of scattering light emission using a glass substrate having one surface roughened as a transparent substrate is carried out. In Japanese Patent Laid-Open No. 09-129375, scattering is performed near an interface between an electrode and an organic layer. Formation of a region is disclosed. However, these are problematic from the viewpoint of mass productivity because they cause breakdown of insulation and nonuniformity of light emission.

In addition, when light is emitted from the organic light emitting device to the sealing substrate, a problem occurs in that light emission from the sealing substrate is reduced.

Accordingly, in manufacturing an organic light emitting device, it is desired to develop an organic light emitting device having improved light extraction efficiency, satisfactory luminance even at low voltage, and blocking moisture and oxygen, thereby improving durability.

In order to solve the above problems, to provide an organic light emitting device that can increase the light extraction efficiency.

Another object of the present invention is to provide an organic EL device capable of improving durability and lifespan of an organic EL device by preventing moisture and oxygen infiltration.

Still another object of the present invention is to provide an organic light emitting device having improved light extraction efficiency as well as an improved hygroscopic function.

The present invention to achieve the above object is a support substrate; An organic light emitting unit formed on one surface of the support substrate and including an organic light emitting layer between a pair of electrodes; An encapsulation substrate positioned above the organic light emitting part; And an encapsulant that couples the support substrate and the encapsulation substrate, wherein an inner surface of the encapsulation substrate is formed of a hygroscopic filler including metal nanoparticles, wherein the light extraction efficiency is improved. to provide.

In another aspect, the present invention provides an organic light emitting device having improved light extraction efficiency, characterized in that the metal nanoparticles are selected from the group consisting of Ag, Au, Cu, Pt, Li, In.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the average diameter of the metal nanoparticles is included in the hygroscopic filler in a variety of sizes.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the moisture-absorbing filler coating thickness is 1 to 50㎛.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the metal nanoparticles are contained 0.1 to 5 parts by weight based on 100 parts by weight of the hygroscopic filler.

In another aspect, the present invention provides an organic electroluminescent device with improved light extraction efficiency, characterized in that the hygroscopic filler further includes an inorganic material or an organometallic compound to perform the hygroscopic function.

In addition, the present invention is the hygroscopic filler is CaO, BaO, SrO, MgO, CaCO ₃ , MgSO ₄ , Aluminum Oxide Acylate, Aluminum Oxide Alkoxide, Aluminum Oxide Alkoxide (Aluminum Oxide) Alkylate) provides an organic light emitting device with improved light extraction efficiency, characterized in that the moisture absorption function, including more than one in the group consisting of.

The present invention also provides an organic EL device having improved light extraction efficiency, characterized in that the support substrate and the sealing substrate are made of thin glass or an optical film.

In another aspect, the present invention is a light extraction, characterized in that the support substrate is laminated to the thin glass and the upper and lower surfaces of the thin glass, the sealing substrate is laminated to the thin film and the upper or upper and lower surfaces of the thin glass and the laminated glass. Provided is an organic EL device having improved efficiency.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the thickness of the support substrate and the thin glass of the sealing substrate is 30 to 1000㎛.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the thin glass and the optical film included in the support substrate and the sealing substrate are the same material.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the optical film is 10 ~ 200㎛ thickness.

In addition, the present invention is the optical film polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene sulfone (PES), transparent polyimide (PI), polyarylate (PAR), It provides an organic electroluminescent device having improved light extraction efficiency, characterized in that at least one selected from the group consisting of polycyclic olefin (PCO), crosslinked epoxy, crosslinked urethane film.

In another aspect, the present invention provides an organic electroluminescent device with improved light extraction efficiency, characterized in that the intermediate adhesive layer between the thin glass and the optical film is a urethane acrylate-based adhesive material which is an ultraviolet curable resin composition.

The present invention also provides an organic EL device having improved light extraction efficiency, further comprising a planarization layer functioning as a buffer layer between an upper surface of the support substrate and a lower surface of the organic EL device.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the surface flatness (Ra) of the planarization layer is 0.5 to 5nm.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the sealing material is provided along the edge of the sealing substrate with a frit, a thermosetting adhesive or a UV curing adhesive.

In another aspect, the present invention provides an organic EL device having improved light extraction efficiency, characterized in that the inner space partitioned by the support substrate and the sealing substrate is filled with an inert gas of nitrogen, neon or argon.

In another aspect, the present invention is an organic electroluminescent device having an improved light extraction efficiency, characterized in that the organic electroluminescent unit is sequentially stacked between the electrode layer and the electrode layer, a hole injection layer, a hole transport layer, an organic light emitting layer, an electron transport layer, an electron injection layer To provide.

The organic light emitting device according to the present invention has the effect of increasing the light extraction efficiency.

In addition, the organic light emitting device according to the present invention has an excellent effect in improving the durability and lifespan of the organic light emitting device by forming a display substrate as a sealing substrate made of thin glass to prevent oxygen and moisture penetration.

In addition, the organic light emitting device according to the present invention has an effect of providing an organic light emitting device having an improved moisture absorption function as well as improved light extraction efficiency is located on the lower surface of the sealing substrate.

1 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present invention.
2 shows a cross-sectional view of a supporting substrate made of thin glass and an optical film.
Figure 3 shows a cross-sectional view of a sealing substrate with the laminated glass and the optical film as a component.
4 is a plan view of an organic light emitting display device according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. First, it should be noted that, in the drawings, the same components or parts have the same reference numerals as much as possible. In describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order not to obscure the subject matter of the present invention.

The terms " about ", " substantially ", etc. used to the extent that they are used herein are intended to be taken to mean an approximation to or in the numerical value of the manufacturing and material tolerances inherent in the meanings mentioned, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

1 is a cross-sectional view of an organic light emitting device according to an exemplary embodiment of the present invention, and FIGS. 2 and 3 show a supporting substrate and a sealing substrate used in the organic light emitting device.

The present invention provides an organic light emitting device that emits light toward a supporting substrate or an encapsulating substrate, and includes a supporting substrate 110, an organic light emitting unit 130 formed on one surface of the supporting substrate, that is, a supporting substrate, and the organic light emitting unit from outside air. The sealing substrate 120 is disposed on the supporting substrate 110 so as to face each other, and a hygroscopic filler having a light extraction efficiency is disposed on the lower surface of the sealing substrate 120.

On the other hand, the light extraction efficiency refers to the ratio of the light emission emitted from the front of the transparent substrate of the device to the light emission of the device, and in order for the light emission in the light emitting layer to be emitted to the atmosphere, some refractive index must pass through the interface of the different media. According to Snell's law of refraction, light incident on each interface at an angle above its critical angle is totally reflected at the interface, guided into the layer, and lost or emitted to the side of the layer, thereby reducing the emission of light by that portion.

When light emitted from the light emitting layer is emitted to the atmosphere through the sealing substrate, a substantial amount of light passing through one side of the thin glass on the sealing substrate is a total reflection effect between the thin glass surface, the adhesive layer, and the optical film surface of the optical film. By being trapped in the sealing substrate, or released to the side of the sealing substrate. As a result of the total reflection effect, a large amount of light does not escape and disappears to the side of the sealing substrate. At this time, light having an incident angle of light greater than the critical angle at the interface of each layer is not emitted to the outside.

The present invention utilizes light that is lost to the side of the substrate using metal surface plasmon resonance to improve the light extraction efficiency. An electromagnetic field called surface plasmon is formed around the metal nanoparticles, and the electromagnetic field causes resonance at visible wavelengths. Light is amplified by resonance around the metal nanoparticles, and the light extraction efficiency by amplification is improved in the process of transmitting the light to the outside.

 Surface plasmons are collective charge density oscillations of electrons occurring on the surface of a metal thin film, and the surface plasmon waves generated are surface electromagnetic waves propagating along the interface between the metal and the dielectric. As the metal exhibiting this phenomenon, metals having an easy dielectric emission and negative dielectric constant are mainly used by external stimuli such as Ag, Au, Cu, Pt, Li, In, and the like.

When light reaches the metal, it creates waves that cause waves on the surface of the metal, which move in the form of ripples on the surface of the lake. If the metal is in the form of small particles, incoming light amplifies the light more effectively by vibrating the particles. Also, if the light has a specific resonance color, the amplification process is stronger.

Surface plasmon resonance is a quantum-electromagnetic phenomenon caused by the interaction of free electrons and light at the interface between metal and dielectric material. This resonance occurs when the energy carried by photons at the interface formed is transferred to the collective transition of free electrons present in the metal. The incident light is amplified by the surface plasmon resonance of the metal and the light extraction efficiency is improved by this amplification.

The metal nanoparticles used in the present invention are preferably included in the group consisting of Ag, Au, Cu, Pt, Li, In and the like, more preferably Ag or Au is included.

The metal nanoparticles are characterized in that the average diameter of 5nm to 500nm. For example, in the case of Ag, light can be amplified by resonating a region having a wavelength of 350-800 nm in a section having an average diameter of 5 nm to 500 nm, and in the case of Au, an average diameter of 5 nm to 500 nm In the phosphorus region, light may be amplified by resonating a region having a wavelength of 450-1000 nm. Therefore, most of the light in the visible light region can be amplified, so that the light extraction efficiency can be improved. In addition, the metal particles are distributed in various sizes, characterized in that included in the hygroscopic filler. Because the region of the resonance frequency is different depending on the size of the metal nanoparticles, it is preferable that the metal nanoparticles are distributed in various sizes to amplify a wide area of visible light.

The metal nanoparticles are preferably contained 0.1 to 7 parts by mass, more preferably 0.5 to 5 parts by mass based on 100 parts by weight of the hygroscopic filler. Within this range, the brightness is increased by improving the light extraction efficiency.

The hygroscopic filler is made of one or more metal nanoparticles are produced by using a polymer as a binder (binder), which is coated on the lower surface of the sealing substrate 120, that is, the inner surface of the sealing substrate 120. The type of the polymer is not particularly limited. However, it should be a transparent material with excellent light transmittance. It is preferable that the thickness of the said hygroscopic type filler is 1-100 micrometers, and it is more preferable that it is 1-50 micrometers.

In addition, the hygroscopic filler may additionally have a hygroscopic function, the hygroscopic material may include an inorganic or organometallic compound having a hygroscopic function, for example, CaO, BaO, SrO, MgO, CaCO ₃ , MgSO ₄ , aluminum oxide acylate (Aluminum Oxide Acylate), aluminum oxide alkoxide (Aluminum Oxide Alkoxide), aluminum oxide alkylate (Aluminum Oxide Alkylate) may be selected from the group consisting of one or more additionally.

The materials of the support substrate 110 and the sealing substrate 120 are not particularly limited, and may be thin glass, transparent optical film, and may be optionally composed of thin glass and optical film.

The optical film used in the present invention is polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene sulfone (PES), transparent polyimide (PI), polyarylate (PAR) , Polycyclic olefin (PCO), crosslinked epoxy, can be used any one selected from the group consisting of a crosslinked urethane film.

FIG. 2 is a cross-sectional view of a non-limiting support substrate using the laminated glass and the optical film as a constituent material, wherein the support substrate 110 is formed of the laminated glass 111 between the pair of optical films 113, and the optical films 113 and A substrate in which a urethane acrylate-based adhesive material, which is an ultraviolet curable resin composition, is laminated as an intermediate adhesive layer 112 between thin glass 111 is provided.

FIG. 3 is a cross-sectional view of a non-limiting sealing substrate using thin glass and an optical film as a constituent material, wherein the sealing substrate 120 has an optical film formed on an upper surface of the thin glass 111 and a hygroscopic filler on the lower surface of the thin glass 111. Indicates that is formed. However, the sealing substrate 120 may not only have an optical film formed on the upper surface of the thin glass 111, but also an optical film 113 formed on the upper and lower surfaces thereof, and a hygroscopic filler may be formed on the lower surface of the lower optical film. Therefore, the optical film is present on the upper surface, the upper surface and the lower surface of the sealing substrate 120, the thin glass 111 and the optical film 113 is bonded by the adhesive layer 112, the metal nanoparticles on the inner surface of the sealing substrate 120 to increase the light extraction efficiency The absorbent moisture-containing filler 114 is formed integrally.

With regard to the laminated glass, the glass 111 is not only excellent in transparency but also excellent in transparency because the glass is excellent in hardness and chemically very stable, has high heat resistance and resistance to reactive materials, and is excellent in transparency to light. It forms a barrier to block oxygen or moisture from the outside. In the case of high gas permeability such as oxygen or moisture through the substrate in relation to the barrier property, the material constituting the display element is affected by the transmitted oxygen or water, which shortens the lifespan and reduces the luminous efficiency. The quality of the product can depend on. As the thin glass is used as a flat panel display device, oxygen and water vapor permeability are measured, and as a result, excellent barrier properties and light transmittance can be obtained.

It is preferable that the thickness of the thin glass 111 of the said support substrate and the said sealing substrate is 30-1000 micrometers.

In the support substrate and the sealing substrate of the present invention, the optical film 113 laminated on the thin glass 111 is preferably a transparent optical film. The optical film may be implemented on both top and bottom surfaces of the thin glass 111. By supporting the optical film with an optical film, the strength of the substrate is increased, so that the glass does not easily break even when the glass is subjected to an external impact. In addition, more than 90% of the glass is damaged at the corners during the process, and the surface is laminated with the optical film. By manufacturing the substrate, the glass strength is preserved. The thickness of the optical film 113 is preferably 10 to 200㎛. When manufacturing the optical film within the above range can prevent the breakage of the thin glass of the substrate and can maintain transparency.

Meanwhile, an adhesion layer 112 is formed between the thin glass 111 and the optical film 113. The material used as the adhesive layer 112 is treated with a surface of a urethane acrylate-based adhesive material as an ultraviolet curable resin composition. It is desirable to.

The adhesive layer 112 may be used as an acrylate adhesive material, a silicone adhesive material, an epoxy adhesive material, etc., but the silicone and epoxy adhesive materials require a long time to reach full curing, resulting in low productivity. And the adhesive strength between the optical film is poor. In addition, moisture permeation through the interface is easy to lower the crosslink density than the ultraviolet curable resin composition used in the present invention has a disadvantage in that the moisture permeation of the adhesive is also inferior.

Accordingly, the urethane acrylate-based adhesive material, which is an ultraviolet curable resin composition used as the adhesive layer of the present invention, has excellent adhesive strength due to the cohesion and toughness peculiar to urethane, and can maintain excellent adhesive strength even under high temperature and high humidity conditions. It has physical properties of moisture transmittance, and is excellent in transparency and high refractive index, which is effective for bonding thin layer adherends such as plastic films used as various optical members, and in particular, improves adhesion between optical films used in liquid crystal displays and the like. A stable flexible substrate can be manufactured.

In addition, the urethane acrylate-based adhesive material, which is an ultraviolet curable resin composition, can solve a problem of dimensional charge formed by thermal deformation or outgasing of a substrate as a solvent-free type.

The adhesive layer 112 may be applied to the thin glass 111 and / or the optical film 113, and may be manually performed to bond the thin glass 111 and the optical film 113, but may be laminated using a laminating method as a non-limiting example of the present invention. do. Representative laminators have a pair of heatable rollers having adjustable pressure and moving at a fixed or adjustable speed, the adhesive can be applied between both materials, namely thin glass and optical film, and after application the rollers of the laminator Will pass through. As such, when the laminating method is used, the thin glass 111 and the optical film 113 can be easily laminated without expensive equipment.

In addition, the sealing substrate 120 is located opposite to the support substrate 110, the sealing substrate 120 is laminated with the optical film 113 on the upper surface of the thin glass 111 and the thin glass 100. In this case, the thin glass and the optical film of the sealing substrate 120 may be formed of the same material as the thin glass and the optical film used in the support substrate 110.

Advantages of using the same material as described above are, firstly, since the support substrate 110 and the sealing substrate 120 are formed of the same material, the thermal expansion coefficients of the support substrate 110 and the sealing substrate 120 are the same, so that the panel mechanical Strength can be improved. Second, by forming the sealing substrate 120 using a glass substrate, the panel can be thinner and lighter than in the case of employing the metal sealing substrate 120. Third, since the substrate using glass is higher in surface smoothness than the sealing substrate 120 made of metal or the like, a gap is hardly formed at the interface with the sealing material, and the adhesive force can be increased.

Therefore, oxygen, moisture, etc. are hard to penetrate from the outside, and sealing performance can be improved.

Meanwhile, according to an embodiment of the present invention, a planarization layer 140 functioning as a buffer layer may be formed on the upper surface of the support substrate 110. The planarization layer 140 may be obtained by partially hydrolyzing the composition for forming an organic or organic-inorganic hybrid layer to form a sol solution, and then coating and curing it on the support substrate 110, which is a transparent substrate. The coating method may be a method such as spin coating, roll coating, bar coating, dip coating, gravure coating, spray coating. The sol state curing method may be used, such as thermal curing, UV curing, infrared curing, high frequency heat treatment. The thickness after the flattening layer is cured is 0.1 µm to 50 µm, preferably 0.1 µm to 20 µm, and more preferably 0.1 µm to 10 µm. If the thickness is thinner than 0.1 μm, it is susceptible to failure due to pinhole defects, and suffers from a limitation in that leakage current occurs later. In addition, if the thickness exceeds 50 μm, cracks and surfaces may occur. There is a problem of uneven formation.

In the present invention, the planarization layer 140 functioning as a buffer layer is important in terms of surface flatness Ra (average of roughness). If the planarization layer 140 is not flat, defects occur when the connection electrode and the organic light emitting layer on the planarization layer are deposited. As a result, leakage current occurs, and thus the life of the organic light emitting part is limited. Accordingly, in the present invention, the surface flatness of the planarization layer 140 is preferably 0.5 nm to 5 nm, and more preferably 0.5 to 1 nm based on the stylus method. In addition, the organic material having a roughness of about 5 nm to 50 nm or a root-mean-square roughness (RMS value) in the maximum peak-to-valley roughness in the present invention. It is desirable to provide an electroluminescent device. In this case, the luminance is increased at the same voltage, thereby improving the quality of the organic light emitting device.

Meanwhile, referring to the organic light emitting unit, the organic light emitting unit 130 is formed of an electrode layer and an organic layer, and the electrode layer 131 supplies a cathode electrode and a hole for supplying electrons. An organic light emitting layer 133 is disposed so that anode electrodes are disposed to face each other, and are disposed between these cathode electrodes and the anode electrode to emit light.

The electrode layer 131 may be formed of ITO, IZO, ZnO, or In ₂ O ₃ , and it is preferable to use indium-zinc oxide (IZO). The indium-zinc oxide (IZO) has a high conductivity in the atmospheric state, has excellent switching characteristics, and has an advantage of fast operating speed. In addition, the IZO can lower the process temperature compared to other materials, the process temperature of the IZO can be carried out at 80 ℃ or less. The electrode layer 131 may be formed in a predetermined pattern.

The electrode layer 131 disposed on the organic light emitting layer 133 may be in contact with the hygroscopic filler 114 of the encapsulation substrate 120. In this case, the electrode layer 131 may absorb moisture generated in the organic light emitting part more quickly, and thus the life of the light emitting device may be improved. There is an advantage that can be extended.

The organic light emitting layer 133 disposed between the electrode layers 131 may be a low molecular or polymer organic layer. When the low molecular organic layer is used, a hole injection layer (HIL), a hole transport layer (HTL), and an organic light emitting layer ( EML (Emission Layer), Electron Injection Layer (EIL), Electron Transport Layer (ETL), etc. may be formed by stacking in a single or complex structure, and these low molecular organic layers may be formed by vacuum deposition. Can be formed.

In the case of the polymer organic layer, the structure may include a hole transporting layer (HTL) and a light emitting layer (EML). In this case, PEDOT is used as the hole transporting layer, and polyvinylvinylene (PPV) and polyfluorene (PPV) are used as the emitting layer. Polymer organic materials such as polyfluorene) may be used and may be formed by screen printing or inkjet printing.

In the organic light emitting unit 130, as anode and cathode voltages are applied to the anode electrode and the cathode electrode, holes injected from the anode electrode are moved to the light emitting layer, and electrons are injected from the cathode electrode to the light emitting layer. Electrons and holes recombine in to generate excitons, and as the excitons change from the excited state to the ground state, the fluorescent molecules in the light emitting layer emit light to form an image. The light emitting layer has a light emitting layer formed of a three-layer structure by sequentially stacking light emitting layers implementing red (R), green (G), and blue (B), or a light emitting layer having a complementary color relationship. It may be formed in a single layer structure consisting of a light emitting layer to implement.

In addition, the support substrate 110 and the sealing substrate 120 may be bonded through the sealing material 150. The sealant 150 bonds the supporting substrate 110 and the sealing substrate 120 through a frit, a thermosetting adhesive, or a UV curable adhesive, and may be positioned along an edge of the sealing substrate 120. The encapsulant 150 forms an encapsulant 150 having a width of 0.1 to 2 mm at an edge portion of the encapsulation substrate 120 in order to bond the supporting substrate 110 including the organic light emitting unit 130 and the encapsulation substrate 120. The sealant 150 may be formed by printing using a screen mask or by applying a sealant dispense or a syringe directly to a corresponding position. In one embodiment of the present invention was provided using a Nagase (XNR 5570) product as a UV (Ultra violate) curing adhesive provided in a rectangular frame shape installed on the outside of the light emitting area.

4 is a plan view of an organic light emitting display device according to an embodiment of the present invention, and it can be seen that the sealing material is formed at the edge of the sealing substrate 120 in a rectangular frame shape.

On the other hand, the inner space partitioned by the support substrate 110 and the sealing substrate 120 is preferably formed in a vacuum or to fill the inert gas. The inert gas is preferably filled with a gas such as nitrogen, neon or argon. In particular, when the inert gas is filled, it is in a state capable of adequately protecting the penetration of oxygen and moisture.

Hereinafter, embodiments of the present invention will be described in detail.

Example  One

A 50 μm thick thin glass is prepared and a 30 μm thick polyethylene terephthalate (PET) film is coated with a urethane acrylate adhesive material, which is an ultraviolet curable resin composition, wherein the film is laminated on both upper and lower surfaces of the thin glass. In order to prepare a support substrate by preparing a sealing substrate, and to prepare a sealing substrate, the polyethylene terephthalate (PET) film is bonded only to the upper surface of the thin glass, and formed by coating a hygroscopic filler on the lower surface of the thin glass. In the type filler, 5 nm, 20 nm, 50 nm, 100 nm, 150 nm, 200 nm, 250 nm, and 300 nm of Ag metal nanoparticles are evenly mixed, respectively. Mix to 5 parts by weight of particles. In addition, CaO and BaO are further mixed to prepare a sealing substrate having improved hygroscopic function.

Next, an organic light emitting device was manufactured using the same. A planarization layer functioning as a buffer layer was formed on the upper surface of the support substrate 110, and the electrode layer of the organic light emitting unit included IZO, and a hole injection layer, a hole transport layer, and an organic layer. A light emitting layer, an electron transporting layer, an electron injection layer, etc., were laminated in a composite structure to manufacture an organic light emitting unit, and an organic light emitting device was manufactured by sealing a sealing substrate and a supporting substrate using a Nagase (XNR 5570) product with a UV curing adhesive. .

Example  2 and 3

In the same manner as in Example 1, the thickness of the thin glass of the support substrate and the sealing substrate is 200㎛, 500㎛, respectively, and the organic light emitting device using a polyethylene terephthalate (PET) film having a thickness of 80㎛ Was prepared.

Example  4

The same process as in Example 1, except that the support substrate and the sealing substrate using only 100㎛ thick thin glass, coated with a hygroscopic filler on the lower surface of the sealing substrate, the coated moisture absorbent filler CaO as a material that absorbs moisture Instead of BaO, CaCO ₃ was included to prepare a sealing substrate to complete an organic light emitting device.

Example  5 and 6

An organic light emitting device was manufactured in the same manner as in Example 4, except that the thicknesses of the thin glass plates of the supporting substrate and the sealing substrate were 200 μm and 500 μm, respectively.

Comparative example  1 to 6

The organic light emitting device was manufactured in the same manner as in Examples 1 to 6, but without the hygroscopic filler.

※ Analysis method

(1) Luminance measurement: Use the PR-650 Spectra Colorimeter set (LS) to evaluate the luminous efficiency and electrical characteristics of OLED as a luminance measurement equipment.

The measurement results are as shown in the following [Table 1].

division Brightness (cd / m 2) Example 1 10950 Example 2 10980 Example 3 11080 Example 4 11040 Example 5 11060 Example 6 11080 Comparative Example 1 9940 Comparative Example 2 9960 Comparative Example 3 9880 Comparative Example 4 9780 Comparative Example 5 9910 Comparative Example 6 9890

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. It will be clear to those who have knowledge of.

Claims (19)

Support substrates;
An organic light emitting unit formed on one surface of the support substrate and including an organic light emitting layer between a pair of electrodes;
An encapsulation substrate positioned above the organic light emitting part; And
Including a sealing material for coupling the support substrate and the sealing substrate,
The inner surface of the sealing substrate is integrally formed with a hygroscopic filler including metal nanoparticles,
The metal nanoparticles are organic EL device with improved light extraction efficiency, characterized in that the average diameter of various sizes of 5nm to 500nm. The method of claim 1,
The metal nanoparticles are selected from the group consisting of Ag, Au, Cu, Pt, Li, In at least one organic light emitting device with improved light extraction efficiency. delete The method of claim 1,
The light extraction efficiency is improved organic electroluminescent device, characterized in that the moisture-absorbing filler coating thickness is 1 to 50㎛. The method of claim 1,
The metal nanoparticles of the organic electroluminescent device with improved light extraction efficiency, characterized in that 0.1 to 5 parts by weight based on 100 parts by weight of the hygroscopic filler. The method of claim 1,
The hygroscopic filler is an organic electroluminescent device with improved light extraction efficiency, characterized in that it further comprises a mineral or an organometallic compound to perform the hygroscopic function. The method of claim 6,
The hygroscopic filler is composed of CaO, BaO, SrO, MgO, CaCO ₃ , MgSO ₄ , Aluminum Oxide Acylate, Aluminum Oxide Alkoxide, Aluminum Oxide Alkylate The organic light emitting device with improved light extraction efficiency, characterized in that the moisture absorption function further comprises one or more in the group. The method of claim 1,
The support substrate and the sealing substrate is improved organic light emitting device, characterized in that made of thin glass or optical film. The method of claim 1,
The support substrate is laminated with a thin film and an optical film on the upper and lower surfaces of the thin glass, the sealing substrate is an optical film laminated on the upper or upper and lower surfaces of the thin glass and the laminated glass is improved light extraction efficiency Organic light emitting device. 10. The method of claim 9,
The thin glass of the support substrate and the sealing substrate has an thickness of 30 to 1000㎛ organic light emitting device with improved light extraction efficiency. 11. The method according to claim 9 or 10,
The thin glass and the optical film included in the support substrate and the sealing substrate is an organic light emitting device with improved light extraction efficiency, characterized in that the same material. 11. The method according to claim 9 or 10,
The optical film has an organic light emitting device with improved light extraction efficiency, characterized in that the thickness of 10 ~ 200㎛. The method of claim 12,
The optical film is polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene sulfone (PES), transparent polyimide (PI), polyarylate (PAR), polycyclic olefin (PCO), cross-linked epoxy, organic light emitting device with improved light extraction efficiency, characterized in that at least one selected from the group consisting of a cross-linked urethane film. 11. The method according to claim 9 or 10,
The intermediate adhesive layer between the thin glass and the optical film is an organic light emitting device with improved light extraction efficiency, characterized in that the urethane acrylate-based adhesive material of the ultraviolet curable resin composition. The method according to any one of claims 1, 2 and 4 to 7,
An organic light emitting device of which light extraction efficiency is improved, further comprising a planarization layer functioning as a buffer layer between an upper surface of the support substrate and a lower surface of the organic light emitting unit. 16. The method of claim 15,
The surface flatness (Ra) of the planarization layer is an organic light emitting device with improved light extraction efficiency, characterized in that 0.5 to 5nm. The method according to any one of claims 1, 2 and 4 to 7,
The sealing material is an organic electroluminescent device having improved light extraction efficiency, characterized in that the frit, a thermosetting adhesive or a UV curing adhesive provided along the edge of the sealing substrate. The method according to any one of claims 1, 2 and 4 to 7,
The internal space partitioned by the support substrate and the sealing substrate is filled with an inert gas of any one of nitrogen, neon or argon, the organic light emitting device with improved light extraction efficiency. The method according to any one of claims 1, 2 and 4 to 7,
The organic electroluminescent device having an improved light extraction efficiency, characterized in that the hole injection layer, the hole transport layer, the organic light emitting layer, the electron transport layer, the electron injection layer is sequentially stacked between the electrode layer and the electrode layer.

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