KR102416347B1 - Organic light emitting display device - Google Patents

Abstract

The present specification discloses an organic light emitting display device. The organic light emitting diode display may include an organic light emitting diode layer disposed in an active area; and a face seal adhesive film provided to cover the organic light emitting device layer to prevent penetration of moisture or oxygen, wherein the face adhesive film includes a first adhesive layer and a second adhesive layer stacked up and down, The first adhesive layer includes a pattern provided at an interface with the second adhesive layer to increase adhesive strength.

Description

Organic light emitting display device {ORGANIC LIGHT EMITTING DISPLAY DEVICE}

The present invention relates to an organic light emitting display device and an encapsulation structure.

The image display device that implements various information on the screen is a key technology in the information and communication era, and is developing in the direction of thinner, lighter, portable and high-performance. Accordingly, an organic light emitting display device (OLED) that displays an image by controlling the amount of light emitted from the organic light emitting layer is in the spotlight.

The organic light emitting diode display is a self-luminous device using a thin light emitting layer between electrodes, and has an advantage in that it can be thinned. A typical organic light emitting display device has a structure in which a pixel driving circuit and an organic light emitting device are formed on a substrate, and an image is displayed while light emitted from the organic light emitting device passes through a substrate or a barrier layer. The organic light emitting device is deteriorated due to internal factors such as deterioration of the electrode and the light emitting layer by oxygen and deterioration due to the reaction between the light emitting layer and the interface, and at the same time it is easily deteriorated by external factors such as external moisture, oxygen, ultraviolet rays and the manufacturing conditions of the device. happens In particular, since external oxygen and moisture have a fatal effect on the lifespan of the device, encapsulation of the organic light emitting display device is very important.

As one of the encapsulation methods, there is a method of sealing the upper portion of the organic light emitting diode with a protective film. The protective film may include a moisture absorbent to absorb penetrating moisture. On the other hand, in order to improve the moisture absorption performance, more desiccant should be included. In this case, an unintended product defect may occur, and a supplementary measure is required.

An object of the present specification is to provide an organic light emitting display device and an encapsulation structure used therein. More specifically, an object of the present specification is to provide a face seal structure composed of a multi-layer to prevent moisture permeation into an organic light emitting diode. In addition, another object of the present specification is to provide a face seal adhesive film having a multilayer structure with enhanced interlayer adhesion.

According to an embodiment of the present specification, an organic light emitting display device is provided. The organic light emitting diode display may include an organic light emitting diode layer disposed in an active area; and a face seal adhesive film provided to cover the organic light emitting device layer to prevent penetration of moisture or oxygen, wherein the face adhesive film includes a first adhesive layer and a second adhesive layer stacked up and down, The first adhesive layer may include a pattern provided on an interface with the second adhesive layer to increase adhesive strength.

According to another embodiment of the present specification, there is provided a face seal adhesive film having a multilayer structure for preventing moisture permeation to an organic light emitting diode. The film may include a first adhesive layer made of a curable resin and a moisture absorbent; A second adhesive layer made of a transparent curable resin and having a first surface adhered to the first adhesive layer and a second surface provided to cover the upper surface of the organic light emitting device layer on an opposite surface of the first surface, the The first adhesive layer may include a specific pattern for increasing adhesive strength compared to a flat adhesive surface by increasing a contact area with the first surface.

According to another embodiment of the present specification, an encapsulation film having a multi-layer structure made of a curable resin and a moisture absorbent is provided. In the encapsulation film, any one or more layers of the plurality of layers include a moisture absorbent, and each layer constituting the plurality of layers relieves interfacial stress due to expansion of the moisture absorbent, and with other layers and an adhesion reinforcing pattern provided at the interface with the other layer in order to increase the contact area of the .

According to the embodiment of the present specification, the moisture permeation prevention performance of the display device may be improved through the face seal adhesive film having a multilayer structure in which interlayer adhesion is strengthened. In addition, according to the embodiment of the present specification, it is possible to reduce the problem of delamination between the layers appearing in the face seal adhesive film having a multilayer structure. Meanwhile, embodiments of the present specification may provide a face seal structure that can be utilized in a display device requiring a narrow bezel.

1 is a plan view illustrating an organic light emitting display device according to an embodiment of the present specification.
2 is a cross-sectional view illustrating a portion of a display area of an organic light emitting diode display according to an exemplary embodiment of the present specification.
3A to 3C are views illustrating an encapsulation layer and a surface adhesive film of an organic light emitting diode display.
4 is a cross-sectional view illustrating an organic light emitting display device according to an exemplary embodiment of the present specification.
5 is a view showing a surface adhesive film according to another embodiment of the present specification.
6 is a cross-sectional view illustrating an organic light emitting display device to which a surface adhesive film is applied according to another exemplary embodiment of the present specification.

In describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, order, or number of the elements are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but other components may be interposed between each component. It should be understood that each component may be “interposed” or “connected”, “coupled” or “connected” through another component. Reference to a device or layer “on” another device or layer includes any intervening layer or other device directly on or in the middle of another device. The size and thickness of each component shown in the drawings are illustrated for convenience of description, and the present invention is not limited to the size and thickness of the illustrated component.

An “organic light emitting display device”, which may also be referred to as a “display device” herein, is used as a general term for an organic light emitting diode panel and a display device employing such an organic light emitting diode panel. In general, the organic light emitting diode display includes a white organic light emitting type and an RGB organic light emitting type. In the white organic light emitting type, each subpixel of a pixel is configured to emit white light, and a set of color filters is used to filter the white light to generate red light, green light and blue light in the corresponding subpixel. Also, the white organic light emitting type may include sub-pixels configured without a color filter to form sub-pixels for generating white light. In the RGB organic light emitting type, the organic light emitting layer in each sub-pixel is configured to emit light of a designated color. For example, one pixel includes a red subpixel having an organic light emitting layer emitting red light, a green subpixel having an organic light emitting layer emitting green light, and a blue subpixel having an organic light emitting layer emitting blue light .

Each feature of the various embodiments of the present invention can be partially or wholly combined or combined with each other, and can be technically variously interlocked and actuated by those skilled in the art, and each of the embodiments can be practiced independently of each other or together in a related relationship. may be carried out. Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a plan view illustrating an organic light emitting display device according to an embodiment of the present specification.

Referring to FIG. 1 , the organic light emitting display device 100 includes at least one active area (A/A), in which an array of pixels is disposed. One or more inactive areas (I/A) may be disposed around the display area. That is, the non-display area may be adjacent to one or more side surfaces of the display area. In FIG. 1 , the non-display area surrounds a rectangular display area. However, the shape of the display area and the shape/arrangement of the non-display area adjacent to the display area are not limited to the example illustrated in FIG. 1 . The display area and the non-display area may have a shape suitable for designing an electronic device on which the display device 100 is mounted. Exemplary shapes of the display area are pentagonal, hexagonal, circular, oval, and the like.

Each pixel in the display area may be associated with a pixel circuit. The pixel circuit may include one or more switching transistors and one or more driving transistors. Each pixel circuit may be electrically connected to a gate line and a data line to communicate with one or more driving circuits such as a gate driver and a data driver located in the non-display area.

The driving circuit may be implemented as a thin film transistor (TFT) in the non-display area. Such a driving circuit may be referred to as a gate-in-panel (GIP). In addition, some components, such as data driver IC, are mounted on a separate printed circuit board, and circuit films such as FPCB (flexible printed circuit board), COF (chip-on-film), TCP (tape-carrier-package), etc. It may be combined with a connection interface (pad, bump, pin, etc.) disposed in the non-display area by using the same. The printed circuit (COF, PCB, etc.) may be located behind the display device 100 .

The organic light emitting diode display 100 may include various additional elements for generating various signals or driving pixels in the display area. Additional elements for driving the pixel may include an inverter circuit, a multiplexer, an electrostatic discharge circuit, and the like. The organic light emitting diode display 100 may also include additional elements related to functions other than driving pixels. For example, the organic light emitting display device 100 may include additional elements that provide a touch sensing function, a user authentication function (eg, fingerprint recognition), a multi-level pressure sensing function, a tactile feedback function, etc. have. The above-mentioned additional elements may be located in the non-display area and/or in an external circuit connected to the connection interface.

The organic light emitting display device according to the present specification includes a thin film transistor and an organic light emitting device on a lower substrate 110 , a face seal on the organic light emitting device, and a barrier film bonded between the substrate and the face encapsulant. ) and the like. The lower substrate 110 is also referred to as a concept including a device and a functional layer formed thereon, for example, a switching TFT, a driving TFT connected to the switching TFT, an organic light emitting element connected to the driving TFT, a protective film, and the like.

The lower substrate 110 supports various components of the organic light emitting diode display 100 and is formed of an insulating material. When the organic light emitting display device 100 is a bottom emission type organic light emitting display device, the lower substrate 110 may be formed of a transparent insulating material, for example, an insulating material such as glass or plastic.

An organic light emitting diode is disposed on the lower substrate 110 . The organic light emitting device includes an anode, an organic light emitting layer formed on the anode, and a cathode formed on the organic light emitting layer. The organic light emitting layer may be configured as a single light emitting layer structure that emits one light, or may be configured as a structure that emits white light by being composed of a plurality of light emitting layers. The organic light emitting diode may be formed in a central portion of the lower substrate 110 to correspond to the display area. When the organic light emitting layer of the organic light emitting device emits white light, a color filter may be formed on the lower substrate 110 .

A passivation layer may cover the organic light emitting diode. The protective layer is formed to protect the organic light emitting diode from external moisture or oxygen.

An encapsulation layer for preventing penetration of a gas such as moisture and/or oxygen may be positioned on the devices formed in the display area A/A. A cotton encapsulant may be used as the encapsulation layer. As an example of the face sealant, a face seal adhesive film may be used. The surface-adhesive film seals the organic light emitting device disposed on the lower substrate 110 , and bonds the lower substrate 110 and the upper substrate.

2 is a cross-sectional view illustrating a portion of a display area of an organic light emitting diode display according to an exemplary embodiment of the present specification.

Referring to FIG. 2 , thin film transistors 102 , 104 , 106 , and 108 and organic light emitting devices 112 , 114 and 116 are positioned on a lower substrate 110 .

The lower substrate 110 may be a glass or plastic substrate. In the case of a plastic substrate, a polyimide-based or polycarbonate-based material may be used to have flexibility.

In the thin film transistor, a semiconductor layer 102, a gate insulating film 103, a gate electrode 104, an interlayer insulating film 105, and source and drain electrodes 106 and 108 are sequentially disposed on a lower substrate 110. can

The semiconductor layer 102 may be made of polysilicon (p-Si), and in this case, a predetermined region may be doped with an impurity. In addition, the semiconductor layer 102 may be made of amorphous silicon (a-Si) or various organic semiconductor materials such as pentacene. Furthermore, the semiconductor layer 102 may be made of oxide. When the semiconductor layer 102 is formed of polysilicon, amorphous silicon is formed and crystallized to change to polysilicon. Such crystallization methods include a rapid thermal annealing (LTA) process, a MILC (Methal Induced Lateral Crystallization) or SLS method. Various methods such as (Sequential Lateral Solidification) may be applied.

The gate insulating layer 103 may be formed of an insulating material such as a silicon oxide layer (SiOx) or a silicon nitride layer (SiNx), and may also be formed of an insulating organic material. The gate electrode 104 may be formed of various conductive materials, for example, Mg, Al, Ni, Cr, Mo, W, MoW, Au, or an alloy thereof.

The interlayer insulating layer 105 may be formed of an insulating material such as a silicon oxide layer (SiOx) or a silicon nitride layer (SiNx), and may also be formed of an insulating organic material. By selectively removing the interlayer insulating layer 105 and the gate insulating layer 103 , a contact hole through which the source and drain regions are exposed may be formed.

The source and drain electrodes 106 and 108 are formed in the form of a single layer or a multi-layered material for the gate electrode 104 on the interlayer insulating layer 105 so that the contact hole is filled.

A passivation layer 107 may be positioned on the thin film transistor. The protective film 107 protects and planarizes the thin film transistor. The passivation layer 107 may be configured in various forms, and may be formed of an organic insulating layer such as benzocyclobutene (BCB) or acryl, or an inorganic insulating layer such as a silicon nitride layer (SiNx) or silicon oxide layer (SiOx), or a single layer. Various modifications are possible, such as being formed of a single layer or composed of double or multiple layers.

The organic light emitting device may have a form in which the first electrode 112 , the organic light emitting layer 114 , and the second electrode 116 are sequentially disposed. That is, the organic light emitting device includes a first electrode 112 formed on the passivation layer 107 , an organic light emitting layer 114 positioned on the first electrode 112 , and a second electrode 116 positioned on the organic light emitting layer 114 . ) can be composed of

The first electrode 112 is electrically connected to the drain electrode 108 of the driving TFT through a contact hole. When the organic light emitting diode display 100 is a top emission type, the first electrode 112 may be made of an opaque conductive material having high reflectance. For example, the first electrode 112 may be formed of Ag, Al, AlNd, Au, Mo, W, Cr, an alloy thereof, or the like.

The bank 109 is formed in the remaining area except for the light emitting area. Accordingly, the bank 109 has a bank hole exposing the first electrode 112 corresponding to the emission region. The bank 109 may be made of an inorganic insulating material such as a silicon nitride film (SiNx) or a silicon oxide film (SiOx), or an organic insulating material such as BCB, an acrylic resin, or an imide resin.

An organic light emitting layer 114 is located on the first electrode 112 exposed by the bank 109 . The organic light emitting layer 114 may include an emission layer, an electron injection layer, an electron transport layer, a hole transport layer, a hole injection layer, and the like.

The second electrode 116 is positioned on the organic light emitting layer 114 . When the organic light emitting diode display 100 is a top emission type, the second electrode 116 is a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). By being formed of a material, light generated from the organic light emitting layer 114 is emitted to the upper portion of the second electrode 116 .

A passivation layer 120 is positioned on the second electrode 116 . In this case, the protective layer 120 may be formed of an inorganic film made of glass, metal, aluminum oxide (AlOx), or a silicon (Si)-based material, or may have a structure in which an organic film and an inorganic film are alternately stacked. The protective layer 120 prevents penetration of oxygen and moisture from the outside in order to prevent oxidation of the light emitting material and the electrode material. When the organic light emitting diode is exposed to moisture or oxygen, a pixel shrinkage phenomenon in which a light emitting area is reduced or a dark spot may occur in the light emitting area.

An encapsulation layer 140 may be disposed on the protective layer 120 . The encapsulation layer 140 encapsulates the organic light emitting diode disposed on the lower substrate 110 . Although various encapsulation structures may be applied, in the present specification, a case in which a face seal structure is used will be described. An example of the face seal structure is a face seal adhesive film. The surface adhesive film 140 serves to bond the lower substrate 110 and the upper substrate 190 together with a sealing function.

A barrier film may be disposed on the encapsulation layer 140 . The barrier film may be a retardation film or a photoisotropic film. When the barrier film has an optical isotropic property, light incident on the barrier film is transmitted as it is without a phase delay. In addition, an organic layer or an inorganic layer may be further disposed on the upper or lower surface of the barrier film. In this case, the inorganic layer may include a silicon oxide layer (SiOx) or a silicon nitride layer (SiOx). The organic layer may include a polymer material such as an acrylic resin, an epoxy resin, polyimide, or polyethylene. The organic or inorganic film formed on the upper or lower surface of the barrier film serves to block the penetration of external moisture or oxygen.

Meanwhile, a lower adhesive layer 160 and a lower encapsulation layer 170 are sequentially formed under the lower substrate 110 . The lower encapsulation layer 170 may include polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyethylene ether phthalate, polycarbonate, polyarylate, and poly It may be formed of one or more organic materials selected from polyether imide, polyether sulfonate, polyimide, and polyacrylate. The lower encapsulation layer 170 serves to prevent moisture or oxygen from penetrating into the substrate from the outside.

The lower adhesive layer 160 is formed of a heat-curable or natural-curable adhesive, and serves to bond the lower substrate 110 and the lower encapsulation layer 170 to each other. For example, the lower adhesive layer 160 may be formed of a material such as Optical Cleared Adhesive (OCA).

3A to 3C are views illustrating an encapsulation layer and a surface adhesive film of an organic light emitting diode display.

The organic light emitting display device 100 includes a lower substrate 110 , an organic light emitting diode OL, a surface adhesive film 140 , and an upper substrate 190 .

The lower substrate 110 is formed of an insulating material and supports various components of the organic light emitting diode display 100 .

The organic light emitting diode OL is disposed on the lower substrate 110 . The organic light emitting device OL includes an anode, an organic light emitting layer formed on the anode, and a cathode formed on the organic light emitting layer. The organic light emitting layer may have a structure of a single light emitting layer that emits one light, or a structure that emits white light by being composed of a plurality of light emitting layers. The organic light emitting diode OL may be formed in a central portion of the lower substrate 110 to correspond to the display area. Various circuit units such as thin film transistors and capacitors for driving the organic light emitting diode OL and various wirings may be formed on the lower substrate 110 .

A passivation layer 120 for protecting the organic light emitting device OL may be positioned to cover the organic light emitting device OL. The protective film 120 may be formed of an inorganic film or may have a structure in which an organic film and an inorganic film are alternately stacked.

The surface adhesive film 140 seals the organic light emitting diode OL, and bonds the lower substrate 110 and the upper substrate 190 to each other. The surface adhesive film 140 may include a curable resin and a moisture absorbent dispersed in the curable resin. The surface adhesive film 140 may include a first adhesive layer 141 and a second adhesive layer 141 .

The first adhesive layer 141 is also referred to as a barrier layer (B-layer), and may be bonded to one surface (a surface facing the lower substrate) of the upper substrate 190 . The first adhesive layer 141 includes a moisture absorbent 141a and a curable resin 141b. The moisture adsorbent 141a of the first adhesive layer 141 adsorbs or removes moisture or oxygen introduced from the outside through a physical or chemical reaction.

The second adhesive layer 142 is also referred to as a transparent layer (T-layer), and may be bonded to the lower substrate 110 and the organic light emitting device. The second adhesive layer 142 may be a thermosetting resin or a photocurable resin.

The upper substrate 190 faces the lower substrate 110 . Specifically, the upper substrate 190 is disposed to face the lower substrate 110 , and a lower surface of the upper substrate 190 is in contact with the surface adhesive film 140 . The upper substrate 190 may be formed of a material such as glass, plastic, or metal, and the constituent material of the upper substrate 190 may be determined according to the emission direction of the organic light emitting diode display 100 .

3B and 3C are diagrams illustrating problems that may appear in the surface adhesive film 140 . First, FIG. 3B shows a floating phenomenon caused by the expansion of the moisture adsorbent 141a.

In order to improve the performance of a surface sealing structure including a surface adhesive film, it is common to increase the content of a moisture absorbent (getter, filler, etc.). However, when the content of the moisture adsorbent is increased, as shown in FIG. 3B , the moisture absorbent expands due to moisture, and stress may be applied to the second adhesive layer (T-layer). Such stress may be transferred to the passivation layer 120 and the organic light emitting diode (OL) layer, thereby causing damage to the passivation layer 120 and/or lifting between the cathode 116 and the cover layer 117 . (See area A) The capping layer is a layer that planarizes the cathode and prevents arcing. In many cases, the adhesive force of the interface between the cathode 116 and the cover layer 117 is smaller than that of other interfaces, and thus, a lifting phenomenon due to an external force may occur at the interface.

3C is a diagram illustrating a phenomenon in which a first adhesive layer (B-Layer) and a second adhesive layer (T-layer) are separated in a protective film (liner film, protect film) removal process. The process of removing the protective film 149 may be performed by the removal roller 320 on the jig 310 . At this time, the first adhesive layer 141 of the surface adhesive film is in a state of being adhered to the upper substrate 190 . The removal roller 320 removes the protective film 149 while moving in a specific direction (eg, arrow direction). If the adhesive force of the first adhesive layer 141 and the second adhesive layer 142 is not sufficient, this In the process, the two layers of part B may be separated from each other.

4 is a cross-sectional view illustrating an organic light emitting display device according to an exemplary embodiment of the present specification.

The organic light emitting display device 100 includes a lower substrate 110 , an organic light emitting diode OL, an encapsulation film 140 - 1 , and an upper substrate 190 .

Detailed descriptions of the lower substrate 110 , the organic light emitting diode OL and the upper substrate 190 are substantially the same as those described with reference to FIGS. 1 to 3 .

The encapsulation (encapsulation) film 140-1 may be a film provided to cover the organic light emitting device layer OL to prevent penetration of moisture or oxygen. The encapsulation (encapsulation) film 140 - 1 may have a multi-layer structure in which a plurality of layers are stacked vertically (vertically). The encapsulation film 140-1 may be composed of a mixture of a curable resin and a moisture absorbent. For example, one or more of the plurality of layers may be made of a curable resin including a moisture absorbent, and the other layers may be made of only a curable resin. Each layer constituting the plurality of layers is provided at the interface with the other layers to relieve interfacial stress (refer to FIG. 3B ) due to the expansion of the moisture absorbent and increase the area in contact with the other upper or lower layers. It may include an adhesion reinforcement pattern.

As an embodiment of the encapsulation film 140 - 1 , a face seal adhesive film having a multilayer structure may be applied to an organic light emitting display device. The surface-adhesive film 140-1 seals the organic light emitting diode OL, and bonds the lower substrate 110 and the upper substrate 190 to each other. The surface-adhesive film 140-1 may include a curable resin and a moisture absorbent dispersed in the curable resin. The curable resin is a base material of the surface adhesive film 140-1, and may be formed of a thermosetting resin or a photocurable resin. The curable resin may be made of a polymer material such as an epoxy or an olefin, but is not limited thereto.

As an embodiment of the surface-adhesive film having a multilayer structure, the surface-adhesive film 140-1 may include a first adhesive layer 141-1 and a second adhesive layer 141-1 stacked vertically.

The first adhesive layer 141-1 is also referred to as a barrier layer (B-layer), and one side of the encapsulation substrate (upper substrate, 190) facing the TFT array substrate 110 (facing the TFT array substrate) surface) can be joined. The first adhesive layer 141-1 includes a moisture absorbent 141-1a and a curable resin 141-1b. The moisture adsorbent 141-1a of the first adhesive layer 141-1 adsorbs or removes moisture or oxygen flowing in from the outside through a physical or chemical reaction or the like. For example, the moisture adsorbent 141-1a is a reactive adsorbent that chemically reacts with moisture or oxygen introduced into the adhesive film 140-1 to adsorb moisture or oxygen, or a reactive adsorbent that absorbs moisture or oxygen penetrating into the encapsulation structure. It may be a physical adsorbent that inhibits penetration by lengthening the migration path. The specific type of the moisture adsorbent 141-1a is not limited. For example, as the moisture adsorbent 141-1a, a reactive adsorbent such as a metal powder such as alumina, metal oxide, metal salt, phosphorus pentoxide (P2O5), or a mixture of two or more types may be used. Another example As the moisture adsorbent 141-1a, a physical adsorbent such as silica, zeolite, titania, zirconia, montmorillonite, etc. may be used.

The metal oxide may be lithium oxide (Li2O), sodium oxide (Na2O), barium oxide (BaO), calcium oxide (CaO), or magnesium oxide (MgO). In addition, the metal salt is lithium sulfate (Li2SO4), sodium sulfate (Na2SO4), calcium sulfate (CaSO4), magnesium sulfate (MgSO4), cobalt sulfate (CoSO4), gallium sulfate (Ga2(SO4)3), titanium sulfate (Ti( SO4)2) or a sulfate such as nickel sulfate (NiSO4). In addition, the metal salt is calcium chloride (CaCl2), magnesium chloride (MgCl2), strontium chloride (SrCl2), yttrium chloride (YCl3), copper chloride (CuCl2), cesium fluoride (CsF), tantalum fluoride (TaF5), niobium fluoride (NbF5), lithium bromide (LiBr), calcium bromide (CaBr2), cesium bromide (CeBr3), selenium bromide (SeBr4), vanadium bromide (VBr3), magnesium bromide (MgBr2), barium iodide (BaI2) or magnesium iodide (MgI2) ) or the like, or a metal chlorate such as barium perchlorate (Ba(ClO4)2) or magnesium perchlorate (Mg(ClO4)2). However, the moisture adsorbent is not limited to the above-described exemplary material.

The first adhesive layer 141-1 has a specific pattern at the interface (boundary surface, bonding surface) with the second adhesive layer 142-1. The specific pattern is provided to increase the adhesive area between the first adhesive layer 141-1 and the second adhesive layer 142-1, and to increase the adhesive force between the two layers compared to when the two layers are adhered with a flat adhesive surface. . That is, since the contact area between the first and second adhesive layers 141-1 and the second adhesive layer increases due to the pattern, the two layers may be more strongly adhered. Also, due to an increase in the area where the two layers contact each other, the amount of stress applied per unit area of the interface during expansion of the moisture adsorbent is reduced. Thereby, breakage of the protective film illustrated in FIG. 3B and/or floating between the cathode-covering layers can be prevented or alleviated.

The specific pattern may occupy an area of at least a portion of a total area of a surface of the first adhesive layer in contact with the second adhesive layer. The area occupied by the pattern formed on one surface of the first adhesive layer (the surface in contact with the second adhesive layer) among the entire surface may be determined based on the interlayer adhesive force required to prevent the problem illustrated in FIG. 3B or 3C. . That is, the pattern occupies an area corresponding to a ratio determined based on a contact area required to improve adhesion among the total area in contact with the first and second adhesive layers. If a larger adhesive force is required between the two layers, the area occupied by the pattern formed on the adhesive surface may increase. The ratio (the ratio of the pattern formation area to the total area of the adhesive surface) may be, for example, 5% or more. In addition, the pattern may be evenly distributed over the entire surface, or may be located only in a specific part (eg, a part corresponding to the bezel area, a part corresponding to the non-display area, etc.) where moisture penetration and expansion of the moisture absorbent are high. .

The first adhesive layer includes a surface (a surface in contact with the second adhesive layer) having an increased surface roughness value compared to a flat surface due to the pattern. That is, the surface roughness of one surface (adhesive surface) of the first adhesive layer is increased by the one or more uneven portions included in the pattern. As the surface roughness is increased by the pattern, the patterned interlayer adhesive surface has a larger surface area than the flat surface. For example, as shown in FIG. 4 , when the cross-section of the pattern has a triangular wave shape and the angle θ of the triangular wave shape is 45 degrees with respect to a flat surface, the surface area of the bonding surface in the unit area is greater than the surface area of the flat surface. √ It can be twice as large. (The unit area refers to an area having a specific area based on a plane.)

The surface roughness value of one surface of the first adhesive layer (a surface in contact with the second adhesive layer) may be determined based on a contact area required to increase the adhesive force between the first adhesive layer and the second adhesive layer. That is, the surface roughness of one surface (a surface in contact with the second adhesive layer) of the first adhesive layer may be determined in consideration of the adhesive force between the first adhesive layer and the second adhesive layer. The surface roughness Sa may be defined by the following equation.

[Equation 1]

Here, x is a coordinate value on the first axis (x=0,1,2,…,N-1), and y is a coordinate value on the second axis (y=0,1,2,…, M-1), wherein z _xy is a surface height value in (x,y) coordinates, N is the maximum value of the first axis coordinates, and M is the maximum value of the second axis coordinates. That is, the surface roughness value is calculated based on the height value with respect to the reference plane of all observation points of the surface (interface between the adhesive layers) having an area of N*M.

In this case, one surface of the first adhesive layer according to the embodiment of the present specification may have a pattern on the surface to have a surface roughness (Sa) value of 0.6 to 17.2 micrometers (um). In addition, the height of the unevenness forming the pattern formed on one surface of the first adhesive layer may be 35% to 50% of the thickness of the first adhesive layer 141-1.

The cross-section of the pattern may have a triangular wave shape as shown in FIG. 4 , but is not limited thereto, and may have a sawtooth wave, a square wave, a sine wave shape, or an irregular concavo-convex shape. In addition, although it is illustrated in FIG. 5 that the pattern height is the same, each unevenness may be configured to have different heights.

The pattern may be formed by laser surface treatment or plasma surface treatment on one surface of the first adhesive layer 141-1. For example, irregularities may be formed by irradiating a laser on one surface of the first adhesive layer 141-1. The process of irradiating the laser may be performed by irradiating the laser with a specific directionality, or may be performed by irradiating the laser randomly without the directionality.

The second adhesive layer 142-1 is also referred to as a transparent layer (T-layer), and may be adhered (bonded) to a protective film on the organic light emitting device and a TFT array substrate around the organic light emitting device. The curable resin of the second adhesive layer 142-1 may be a curable resin containing the same material as the curable resin 141-1b constituting the first adhesive layer 141-1, or a curable resin containing a different substance. it may be For example, a thermosetting polymer comprising at least one thermally curable functional group such as a glycidyl group, an isocyanate group, a hydroxy group, a carboxyl group, or an amide group. It can be resin. In addition, the second adhesive layer 142-1 may be made of a transparent curable resin. The second adhesive layer 142-1 has a surface (a first surface) bonded to the first adhesive layer 141-1 and an opposite surface (a second surface) provided to cover the upper surface of the organic light emitting device layer. Since the resin constituting the second adhesive layer 142-1 has a predetermined viscosity, when the second adhesive layer is coated on the first adhesive layer, the first surface of the second adhesive layer follows the shape of the pattern formed on the first adhesive layer. is formed

Recently, a display panel with a narrower edge (bezel) has been studied for aesthetics or miniaturization of the display device. In such a narrow bezel organic light emitting display device, since the path through which moisture/oxygen that has penetrated through the side moves to the organic light emitting device becomes shorter, it is requested to improve the moisture absorption performance inside the encapsulation structure such as a surface adhesive film. situation to be For this purpose, it is preferable to increase the content of the moisture absorbent in the surface adhesive film, but defects such as interlayer lifting may occur due to the increased moisture absorbent. Accordingly, the organic light emitting display device to which the above-described pattern is applied can withstand the interfacial stress corresponding to an increase in the content of the moisture adsorbent, and thus lifespan and reliability can be increased.

5 is a view showing a surface adhesive film according to another embodiment of the present specification.

The surface adhesive film 140-2 includes a first adhesive layer 141-2 and a second adhesive layer 142-2 bonded to each other, a first protective film 148-2 attached to the outer surface of the first adhesive layer, and a 2 It may include a second protective film 149-2 attached to the outer surface of the adhesive layer.

The first adhesive layer 141 - 2 may be a mixture of a curable resin and a moisture absorbent, and the second adhesive layer 142 - 2 may be a transparent curable resin. The first protective film 148 - 2 and the second protective film 149 - 2 are formed with the first adhesive layer 141 - 2 and the second adhesive layer 142 until the adhesive film 140 - 2 is adhered to the organic light emitting display device. It is a film for supporting/protecting -2).

The surface adhesive film 140-2 is provided with protective films 148-2 and 149-2 attached to the upper and lower surfaces, respectively. Accordingly, the first protective film 148-2 adhered to the surface-adhesive film 140-2 may be removed prior to lamination of the surface-adhesive film 140-2 on the lower surface of the upper substrate 190. have.

The first protective film 148 - 2 and the second protective film 149 - 2 may be formed of a general polymer material. For example, the first protective film 148-2 and the second protective film 149-2 may include a polyethylene terephthalate film, a polytetrafluoroethylene (PTFE) film, a polyethylene film, Polypropylene film, polyisobutylene film, polybutadiene film, vinyl chloride copolymer film, polyurethane film, ethylene-vinyl acetate film, An ethylene-propylene copolymer film, an ethylene-acrylic acid ethyl copolymer film, an ethylene-acrylic acid methyl copolymer film, or a polyimide film can

A first adhesive layer 141 - 2 is formed on the first protective film 148 - 2 . The material of the first adhesive layer 141 - 2 and the pattern formed on one surface are the same as those described with reference to FIG. 4 . The first adhesive layer 141 - 2 may be formed on the first protective film 148 - 2 in such a way that it is coated on the first protective film 148 - 2 .

The second adhesive layer 142 - 2 is disposed between the first adhesive layer 141 - 2 and the second protective film 149 - 2 . The curable resin of the second adhesive layer 142 - 2 may be the same material as the curable resin constituting the first adhesive layer 141 - 2 or may be a curable resin made of a different material. The second adhesive layer 142-2 is formed on the second protective film 149-2 in such a way that it is coated on the second protective film 149-2, and the first adhesive layer 141-2 and the second adhesive layer ( 142-2) may be bonded to prepare a surface adhesive film 140-2.

The second adhesive layer 142 - 2 may further include a predetermined pattern provided on a surface that is bonded to the TFT array substrate, that is, a surface that is in contact with the second protective film 149 - 2 . The cross-section of the pattern may have a triangular wave shape as shown in FIG. 5 , but is not limited thereto, and may have a sawtooth wave, a square wave, a sine wave shape, or an irregular concavo-convex shape. In addition, although it is illustrated in FIG. 5 that the pattern height is the same, each unevenness may be configured to have different heights. The pattern is for removing air bubbles trapped between the TFT array substrate and the second adhesive layer 142 - 2 . This will be described in detail with reference to FIG. 6 .

6 is a cross-sectional view illustrating an organic light emitting display device to which a surface adhesive film is applied according to another exemplary embodiment of the present specification.

In the process of bonding the surface-adhesive film 140-2 and the TFT array substrate, the second adhesive layer 142-2 of the surface-adhesive film 140-2 and the TFT array substrate 110, or the second adhesive layer 142- In some cases, bubbles are trapped between 2) and the organic light emitting device layer OL. These bubbles may become a path for moisture to penetrate and cause pixel defects.

However, when a predetermined pattern (eg, a stripe pattern) is provided on the lower surface of the second adhesive layer 142 - 2 , air bubbles may escape into a space between the patterns. Accordingly, the cohesion of the upper and lower substrates can be improved, and pixel defects caused by moisture permeation can be improved.

The above description and the accompanying drawings are merely illustrative of the technical spirit of the present invention, and those of ordinary skill in the art to which the present invention pertains can combine configurations within a range that does not depart from the essential characteristics of the present invention. , various modifications and variations such as separation, substitution and alteration will be possible. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100: organic light emitting display device
120: shield
140, 140-1, 140-2: adhesive film

Claims (15)

an organic light emitting diode layer disposed in an active area; and
and a face seal adhesive film provided to cover the organic light emitting device layer to prevent penetration of moisture or oxygen,
The surface adhesive film includes a first adhesive layer and a second adhesive layer stacked up and down,
The first adhesive layer includes a curable resin and a moisture absorbent,
The first adhesive layer includes a pattern provided to increase the adhesive force at the interface with the second adhesive layer,
The surface roughness of the interface of the first adhesive layer is 0.6 to 17.2 micrometers (um), and the height of the pattern is 35% to 50% of the thickness of the first adhesive layer,
Each of both surfaces of the second adhesive layer facing each other includes a pattern for increasing adhesion and a pattern for removing bubbles corresponding to the pattern of the first adhesive layer. According to claim 1,
In the pattern, the first adhesive layer occupies at least a portion of the total area of the surface in contact with the second adhesive layer,
The ratio of the area occupied by the pattern is determined based on a contact area required to increase the adhesive force between the first adhesive layer and the second adhesive layer. According to claim 1,
The first adhesive layer includes a surface having an increased surface roughness value compared to a flat surface due to the pattern,
The surface roughness value of the one surface is determined based on a contact area required to increase adhesion between the first adhesive layer and the second adhesive layer. 4. The method of claim 3,
The surface roughness value Sa is calculated by the following formula,

Here, x is a coordinate value on the first axis (x=0,1,2,…,N-1), and y is a coordinate value on the second axis (y=0,1,2,…, M-1), wherein z _xy is a surface height value in (x,y) coordinates, N is the maximum value of the first axis coordinates, and M is the maximum value of the second axis coordinates. . According to claim 1,
An organic light emitting display device having a cross-section of the pattern having at least one of a triangular wave, a sawtooth wave, a square wave, and a sine wave shape. According to claim 1,
The second adhesive layer is adhered to the protective film on the organic light emitting device and the TFT array substrate around the organic light emitting device,
The first adhesive layer is bonded to an encapsulation substrate facing the TFT array substrate. 7. The method of claim 6,
The pattern for removing bubbles is provided on a surface of the second adhesive layer that is adhered to the TFT array substrate. delete According to claim 1,
The moisture adsorbent is at least one of a reactive adsorbent and a physical adsorbent. According to claim 1,
The second adhesive layer is an organic light emitting display device comprising a transparent curable resin. As a face seal adhesive film having a multilayer structure that prevents moisture permeation to an organic light emitting device,
a first adhesive layer comprising a curable resin and a moisture absorbent; and
A second adhesive layer comprising a transparent curable resin and having a first surface adhered to the first adhesive layer and a second surface provided to cover the upper surface of the organic light emitting device layer on the opposite surface of the first surface,
The first adhesive layer includes a specific pattern that increases the adhesive force compared to the flat adhesive surface by increasing the contact area with the first surface,
The surface roughness of the surface on which the specific pattern of the first adhesive layer is disposed is 0.6 to 17.2 micrometers (um), and the height of the specific pattern is 35% to 50% of the thickness of the first adhesive layer,
The first surface of the second adhesive layer includes a pattern for increasing adhesion corresponding to the specific pattern, and the second surface of the second adhesive layer includes a pattern for removing bubbles. 12. The method of claim 11,
The specific pattern is a surface adhesive film having a surface roughness determined based on a contact area required to increase the adhesive force between the first adhesive layer and the second adhesive layer. 13. The method of claim 12,
The specific pattern is a surface adhesive film made through laser (laser) surface treatment or plasma (plasma) surface treatment. 12. The method of claim 11,
The pattern disposed on the second surface of the second adhesive layer is a pattern for removing air bubbles trapped between the TFT array substrate and the second adhesive layer. delete

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