KR102430099B1 - Electroluminescence display device - Google Patents

Abstract

The present invention relates to an electroluminescent display having a cover film in a bending region.
The electroluminescent display device of the present invention is configured to cover a flexible substrate including a display area and a bending area extending from at least one side of the display area, a plurality of pixels provided in the display area, and the plurality of pixels, A first adhesive layer configured to have a concave cross section of one side corresponding to the bending region, a polarizing layer disposed on the first adhesive layer, and the first adhesive layer configured to have a concave cross section and a cover film configured to relieve bending stress in the bending region, and a first member configured to fill a space between the cover film and the first adhesive layer configured to have a concave cross-section at one side. .

Description

Electroluminescent display device {ELECTROLUMINESCENCE DISPLAY DEVICE}

The present invention relates to an electroluminescent display including a cover film in a bending region.

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

Since the organic light emitting display device is implemented without a separate light source, it is easy to be implemented as a flexible display device. In this case, a flexible material such as plastic or a metal foil is used as a substrate of the organic light emitting diode display.

Meanwhile, in order to implement a flexible display device, research is being conducted to bend or bend various parts of the display device. These studies are mainly conducted for new design and UI/UX, and in some cases, such studies are also conducted to reduce the area of the corner of the display device.

While manufacturing a display device using a substrate having flexibility, it is necessary to secure flexibility such as a substrate, various insulating layers formed on the substrate, and wiring formed of a metal material.

In the case of wiring, when a substrate on which wiring is formed is bent, a crack may be generated in the wiring due to stress caused by bending. When a crack occurs in the wiring, normal signal transmission is not performed, so that the thin film transistor or the organic light emitting diode may not operate normally, which may lead to a defect in the display device.

In the case of the insulating layer, the flexibility of the inorganic or organic film material itself constituting the insulating layer is considerably lower than that of the wiring. Accordingly, when the substrate on which the insulating layer is formed is bent, cracks may also be generated in the insulating layer due to the stress caused by the bending.

When a crack is generated in a portion of the insulating layer, the generated crack is propagated to other regions of the insulating layer and propagated to a wiring in contact with the insulating layer, which may lead to a defect in the display device.

Accordingly, the inventors of the present invention have recognized the need to minimize the stress applied to the wiring and the insulating layer disposed in the bending region in order to minimize defects in the display device. Therefore, the inventors of the present invention have devised a new structure capable of optimizing the neutral plane in the bending region.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

An electroluminescent display device according to an embodiment of the present invention is configured to cover a flexible substrate including a display area and a bending area extending from at least one side of the display area, a plurality of pixels provided in the display area, and a plurality of pixels, , a first adhesive layer configured to have a cross section of one side corresponding to the bending region has a concave shape, a polarizing layer disposed on the first adhesive layer, and a first adhesive layer configured to have a cross section of one side having a concave shape. , a cover film configured to relieve bending stress in the bending region, and a first member configured to fill a space between the cover film and the first adhesive layer configured to have a concave cross-section at one side.

The first member is configured to relieve bending stress between the first adhesive layer and the cover film.

It is disposed in the bending area and further includes a connection part electrically connected to the plurality of pixels, wherein the cover film is positioned on the connection part to cover the connection part.

The cover film is characterized in that it is a planarization film that positions the neutral plane on the connection part when the substrate is bent.

The cover film is characterized in that it is composed of at least one adhesive layer having different adhesive strengths on one surface and the other surface corresponding to the one surface.

The cover film includes a support layer between the plurality of adhesion layers.

The adhesive layer is characterized in that it is composed of one of acrylic (acryl), urethane (urethane) and acrylic urethane (acrylic urethane).

The Young's modulus of the cover film is characterized in that it is 1 to 300Mpa.

The first member is configured to prevent a portion of the connecting portion from being exposed between the cover film and the concave side of the first adhesive layer when the substrate is bent.

The first member is characterized in that it is composed of one of acrylic (acryl) or urethane acrylate (urethane acrylate) so as to cover a part of the connecting portion.

The electroluminescent display device further includes a protective layer disposed on the polarizing layer and a second adhesive layer disposed between the protective layer and the polarizing layer, wherein a cross-section of one side of the second adhesive layer has a concave shape, and the first adhesive layer It is characterized in that it is configured to correspond to the concave side of the.

The first member is characterized in that at least a part of the concave side of the second adhesive layer is filled.

The electroluminescent display device is configured to further include a circuit part connected to the connection part and a second member positioned between the circuit part and the cover film.

The second member is configured to cover a part of the connection part between the cover film and one side of the circuit part.

An electroluminescent display device according to another embodiment of the present invention includes a flexible substrate having a display area and a non-display area, a polarizing layer positioned on the display area of the flexible substrate, and a lower surface of the polarizing layer for adhesion to the flexible substrate It comprises a first adhesive layer that enables, characterized in that the barrier film (Barrier film) that prevents moisture permeation between the flexible substrate and the polarizing layer due to the first adhesive layer is not required.

It further includes a second adhesive layer on the upper surface of the polarizing layer and allowing adhesion to the cover glass CG thereon.

It is located in the non-display area and is located at the end of the flexible substrate and further includes a pad part that enables electrical connection with the signal supply circuit part.

The first adhesive layer, the polarizing layer, and the second adhesive layer form an optical double adhesive (Double OCA) structure, and are disposed between the pad part and the optical double adhesive structure and further include a neutral plane raising film in the non-display area.

It further includes an organic member filling between the end of the optical double adhesive structure and one end of the neutral plane lifting film, and between the opposite end of the neutral plane lifting film and the pad portion.

At the end of the optical double adhesive structure, at least one of the first adhesive layer and the second adhesive layer has an end surface that is concave compared to the end surface of the polarizing layer to accommodate the filling of the organic member.

In the non-display area, the flexible substrate has a bending shape, and the signal supply circuit part connected to the pad part is located on the opposite side of the polarizing layer with the display area interposed therebetween, and the optical double adhesive structure, the neutral plane raising film, and the organic member are formed. A specific bending curvature characteristic may be secured by filling.

The present invention can minimize the occurrence of cracks in the wiring and the insulating layer in the bending region by providing the cover film.

According to the present invention, it is possible to minimize the occurrence of cracks in the wiring and the insulating layer in the space between the adhesive layer and the cover film of the display area by providing the first member.

Effects according to the embodiments of the present specification are not limited by the contents exemplified above, and more various effects are included in the present specification.

1 is a schematic plan view illustrating an organic light emitting diode display according to an exemplary embodiment.
FIG. 2 is a cross-sectional view of the organic light emitting diode display taken along line II-II' of FIG. 1 .
3 is a schematic cross-sectional view illustrating compressive and tensile forces applied to layers respectively disposed above and below a neutral plane when the organic light emitting diode display is bent.
4 is a cross-sectional view of a cover film applied to an organic light emitting display device according to an exemplary embodiment of the present invention.
5 is a cross-sectional view of another cover film applied to an organic light emitting diode display according to another exemplary embodiment.
FIG. 6 is a cross-sectional view illustrating a structure of the organic light emitting diode display shown in FIG. 2 in a final bent state.

Advantages and features of the present specification and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present specification are exemplary, and thus the present specification is not limited to the illustrated matters. Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. When 'including', 'having', 'consisting', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the case in which the plural is included is included unless specifically stated otherwise. In interpreting the components, it is interpreted as including an error range even if there is no separate explicit description.

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between two parts unless 'directly' is used. 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. 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.

Although first, second, etc. are used to describe various elements, these elements are not limited by these terms. These terms are only used to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the spirit of the present invention.

The size and thickness of each component shown in the drawings are illustrated for convenience of description, and the present invention is not necessarily limited to the size and thickness of the illustrated component. Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic plan view illustrating an organic light emitting diode display according to an exemplary embodiment. In this case, the present invention will be described using an organic light emitting diode display as an example for convenience of description, but the present invention is not limited thereto.

The substrate (or flexible substrate) 110 includes an active area (AA) and a non-active area (NA) surrounding the display area. In this case, the non-display area NA may include the bending area BA. The display area AA is an area in which an image is displayed in an organic light emitting diode display (or an electroluminescent display), and the display area AA includes an organic light emitting device 180 and a device for driving the organic light emitting device 180 to be described later. Various driving elements may be disposed. The non-display area NA is an area in which an image is not displayed in the organic light emitting diode display, and is an area in which various signal lines such as the scan line SL and circuit parts such as the wiring 170 and the gate driver 190 are formed. The gate driver 190 may be disposed in the form of a gate in panel (GIP) as shown in FIG. 1 .

A pad (or pad part) 195 is disposed in the non-display area NA. Referring to FIG. 1 , a pad 195 is disposed on one side of the substrate 110 in the non-display area NA. The pad 195 is a metal pattern to which an external module (or a signal supply circuit unit or a circuit unit), for example, a flexible printed circuit board (FPCB), a chip on film (COF), or the like is bonded.

The wiring 170 is disposed in the non-display area NA. The wiring 170 is a wiring 170 for transmitting a signal (voltage) from an external module bonded to the pad 195 to the display area AA or the gate driver 190 . For example, various signals for driving the gate driver 190 , such as a data signal, a high potential voltage VDD, and a low potential voltage VSS, for driving the gate driver 190 may be transmitted through the wiring 170 . The wiring 170 may be simultaneously formed of the same material as various conductive elements disposed in the display area AA.

A bending area BA is defined in the non-display area NA adjacent to the display area AA. The bending area BA is an area for disposing the pad 195 disposed in the non-display area NA of the substrate 110 and the external module bonded to the pad 195 on the rear side of the substrate 110 . That is, as the portion corresponding to the bending area BA is bent in the substrate 110 (in the direction of the arrow in FIG. 1 ), the external module bonded to the pad 195 of the substrate 110 moves toward the back side of the substrate 110 . and the external module may not be visually recognized when viewed from the front of the substrate 110 . In addition, as the portion corresponding to the bending area BA is bent in the substrate 110 , the size of the non-display area NA viewed from the front surface of the substrate 110 is reduced, so that a narrow bezel may be implemented. have.

FIG. 2 is a cross-sectional view of the organic light emitting diode display taken along line II-II' of FIG. 1 .

The organic light emitting diode display according to the exemplary embodiment shown in FIG. 2 is a top emission type in which light emitted from the organic light emitting diode is emitted to an upper portion of the organic light emitting display through a cathode. It is an organic light emitting display device. However, the present invention is not limited to a top emission type organic light emitting display device, and may be applied to a bottom-emission type organic light emitting display device and a dual side-emission type organic light emitting display device.

The substrate (or flexible substrate) 110 supports various components of the organic light emitting diode display 100 . The substrate 110 may be made of a plastic material having flexibility, for example, polyimide (PI). When the substrate 110 is made of polyimide (PI), the manufacturing process proceeds in a situation where a support substrate made of glass is disposed under the substrate 110, and the support substrate may be released after the manufacturing process is completed. have. Also, after the supporting substrate is released, a back plate for supporting the substrate may be disposed under the substrate 110 .

The thin film transistor 130 is disposed on the substrate 110 . The thin film transistor 130 includes an active layer 131 made of polysilicon, a gate electrode 134 , a source electrode 132 , and a drain electrode 133 . The thin film transistor 130 is a driving thin film transistor and has a top gate structure in which the gate electrode 134 is disposed on the active layer 131 . 2 shows only a driving thin film transistor among various thin film transistors that may be included in the organic light emitting diode display 100 for convenience of explanation, but other thin film transistors such as a switching thin film transistor may also be included in the organic light emitting display 100 have. In addition, although the thin film transistor 130 has been described as having a coplanar structure in this specification, the thin film transistor 130 may be implemented in other structures such as a staggered structure. In addition, although the thin film transistor 130 is disposed on the substrate 110 in FIG. 2 , the present invention is not limited thereto, and based on the type and material of the substrate 110 , the structure and type of the thin film transistor 130 , etc. A multi-buffer layer may be disposed between the substrate 110 and the thin film transistor 130 .

The active layer 131 of the thin film transistor 130 is disposed on the substrate 110 . The active layer 131 includes a channel region CA in which a channel is formed when the thin film transistor 130 is driven, and a source region SA and a drain region DA on both sides of the channel region CA. The channel region CA, the source region SA, and the drain region DA may be defined by ion doping (impurity doping).

The active layer 131 of the thin film transistor 130 may be made of polysilicon. Accordingly, polysilicon is formed by depositing an amorphous silicon (a-Si) material on the buffer layer 111 and performing a dehydrogenation process, a crystallization process, an activation process, and a hydrogenation process, and patterning the polysilicon to form an active layer 131 may be formed. When the active layer 131 is made of polysilicon, the thin film transistor 130 may be an LTPS thin film transistor 130 using low temperature poly-silicon (LTPS). Since the polysilicon material has high mobility, when the active layer 131 is made of polysilicon, energy consumption is low and reliability is excellent.

Also, the active layer 131 of the thin film transistor 130 may be made of an oxide semiconductor material. The active layer 131 of the thin film transistor 130 may be made of a metal oxide, for example, may be made of a metal oxide such as IGZO, but is not limited thereto. Since the oxide semiconductor material has a larger bandgap compared to the silicon material, electrons cannot cross the bandgap in the off state, and thus the off-current is low.

A gate insulating layer 112 is disposed on the active layer 131 . The gate insulating layer 112 may be formed of a single layer of inorganic silicon nitride (SiNx) or silicon oxide (SiOx) or a multilayer of silicon nitride (SiNx) or silicon oxide (SiOx). The gate insulating layer 112 has a contact hole through which the source electrode 132 and the drain electrode 133 respectively contact the source area SA and the drain area DA of the active layer 131 . In FIG. 2 , the gate insulating layer 112 is illustrated as being planarized for convenience of explanation, but the gate insulating layer 112 may be formed along the shapes of the components disposed thereunder.

A gate electrode 134 is disposed on the gate insulating layer 112 . A metal layer such as molybdenum (Mo) is formed on the gate insulating layer 112 and the metal layer is patterned to form a gate electrode 134 . The gate electrode 134 is disposed on the gate insulating layer 112 to overlap the channel region CA of the active layer 131 .

An interlayer insulating layer 115 is disposed on the gate electrode 134 . The interlayer insulating layer 115 may be formed of a single layer of inorganic silicon nitride (SiNx) or silicon oxide (SiOx) or a multilayer of silicon nitride (SiNx) or silicon oxide (SiOx). The interlayer insulating layer 115 has a contact hole through which the source electrode 132 and the drain electrode 133 respectively contact the source area SA and the drain area DA of the active layer 131 . In FIG. 2 , the interlayer insulating layer 115 is illustrated as being planarized for convenience of description, but the interlayer insulating layer 115 may be formed along the shapes of components disposed thereunder.

A source electrode 132 and a drain electrode 133 are disposed on the interlayer insulating layer 115 . The source electrode 132 and the drain electrode 133 may be formed of a conductive metal material, for example, may have a three-layer structure of titanium (Ti)/aluminum (Al)/titanium (Ti). Each of the source electrode 132 and the drain electrode 133 has a source region SA and a drain region DA of the active layer 131 through a contact hole provided in the gate insulating layer 112 and the interlayer insulating layer 115 . connected to each

The storage capacitor 120 is disposed on the substrate 110 . The storage capacitor 120 includes a first electrode 121 disposed on the gate insulating layer 112 and a second electrode 122 disposed on the interlayer insulating layer 115 . The first electrode 121 of the storage capacitor 120 is simultaneously formed of the same material as the gate electrode 134 of the thin film transistor 130 , and the second electrode 122 of the storage capacitor 120 is formed of the thin film transistor 130 . It may be simultaneously formed of the same material as the source electrode 132 and the drain electrode 133 of Accordingly, since the storage capacitor 120 may be formed during the manufacturing process of the thin film transistor 130 without the need for a separate additional process, efficiency exists in terms of process cost and process time.

A planarization layer 113 is disposed on the thin film transistor 130 and the storage capacitor 120 . In this case, the planarization layer 113 may protect the thin film transistor 130 and the storage capacitor 120 . In addition, the planarization layer 113 planarizes the upper portions of the thin film transistor 130 and the storage capacitor 120 , so that the organic light emitting diode 180 can be formed more reliably. In this case, the planarization layer 113 may include a contact hole through which the anode 181 of the organic light emitting diode 180 is connected to the thin film transistor 130 .

The organic light emitting diode 180 is disposed on the planarization layer 113 . The organic light emitting device 180 is formed on the planarization layer 113 and is electrically connected to the source electrode 132 of the thin film transistor 130, the anode 181, the organic layer 182 and the organic layer (182) disposed on the anode 181 ( and a cathode 183 formed thereon. Since the organic light emitting diode display 100 is a top emission type organic light emitting display device, the anode 181 provides a reflective layer for reflecting the light emitted from the organic layer 182 toward the cathode 183 and holes in the organic layer 182 . It may include a transparent conductive layer for supply. However, it may be defined that the anode 181 includes only a transparent conductive layer and the reflective layer is a separate component from the anode 181 .

The organic layer 182 is an organic layer for emitting light of a specific color, and may include one of a red organic emission layer, a green organic emission layer, a blue organic emission layer, and a white organic emission layer. If the organic layer 182 includes a white organic light emitting layer, a color filter for converting white light from the white organic light emitting layer into light of a different color may be disposed on the organic light emitting device 180 . In addition, the organic layer 182 may further include various organic and/or inorganic layers such as a hole transport layer, a hole injection layer, an electron injection layer, and an electron transport layer in addition to the organic light emitting layer. The cathode 183 may be made of a transparent conductive material, and may include, for example, a transparent conductive oxide such as IZO or ytterbium (Yb).

A bank 114 is disposed on the anode 181 and the planarization layer 113 . Since the bank 114 is positioned adjacent to each pixel disposed in the display area AA to distinguish each pixel, the bank can be said to define each pixel area. The bank 114 may be formed of an organic material. For example, the bank 114 may be made of polyimide, acryl, or benzocyclobutene (BCB)-based resin, but is not limited thereto.

An encapsulation unit 140 may be stacked on the organic light emitting device 180 . In this case, the encapsulation unit 140 may have a structure in which inorganic layers 141 and 143 and organic layers 142 are alternately stacked. Accordingly, the encapsulation unit 140 prevents the organic light emitting device 180 vulnerable to moisture and/or oxygen from being exposed to moisture and/or oxygen, so that the organic light emitting device 180 may be protected.

A first adhesive layer 174 may be disposed on the encapsulation unit 140 . The first adhesive layer 174 may cover the encapsulation unit 140 . Accordingly, the first adhesive layer 174 may be configured to cover the plurality of pixels provided in the display area AA. In this case, the first adhesive layer 174 may be configured such that a cross-section of one side corresponding to the bending area BA has a concave shape. The cross-section having a concave shape of the first adhesive layer 174 is formed by grinding the cross-section to correspond to the bending area BA while applying pressure to the first adhesive layer 174 and then removing the pressure. can be In this case, in order to form a concave cross-section of one side of the first adhesive layer 174 , the first adhesive layer 174 may be made of an elastic material that can be contracted when pressure is removed. For example, the first adhesive layer 174 may be formed of at least one of silicone or an acryl-urethane series material.

/4지연층과 선편광층을 포함할 수 있다. 또한 일면 또는 양면에 아세트산 셀롤로오스계의 편광 보호막이 적층된 형태로 구성될 수 있다.A polarization layer 175 may be disposed on the first adhesive layer 174 . The polarization layer 175 may be disposed on the display area AA to emit light emitted from the display area AA to the outside, and may absorb light incident from the outside to increase image visualization. At this time, the polarizing layer 175 is a polyvinyl alcohol (PVA)-based resin film mixed with a dichroic dye and uniaxially stretched to align the dichroic dye.

It may include a /4 delay layer and a linear polarization layer. In addition, it may be configured in a form in which a cellulose acetate-based polarization protective film is laminated on one or both surfaces.

The first adhesive layer 174 may be disposed on the lower surface of the polarization layer 175 to adhere the polarization layer 175 to the substrate 110 . In this case, the first adhesive layer 174 may cover the encapsulation unit 140 , thereby preventing external moisture and oxygen from penetrating into the organic light emitting device 180 . Accordingly, the organic light emitting diode 180 disposed under the first adhesive layer 174 may be protected. Accordingly, there is no need to provide a barrier film between the substrate 110 and the polarizing layer 175 to prevent moisture permeation. In addition, since the barrier film may not be used, the thickness of the organic light emitting diode display 100 may be reduced.

A second adhesive layer 176 may be disposed on the polarization layer 175 . The second adhesive layer 176 may be configured such that a cross-section of one side corresponding to the bending area BA has a concave shape. In this case, one side of the second adhesive layer 176 may be disposed to correspond to the concave side of the first adhesive layer 174 . The concave cross section of the second adhesive layer 176 may be formed in the same manner as the concave cross section of the first adhesive layer 174 . In this case, the second adhesive layer 176 may be formed of the same material as the first adhesive layer 174 .

A protective layer (or Cover Glass (CG)) 179 may be disposed on the second adhesive layer 176 . In this case, the second adhesive layer 176 may be positioned on the upper surface of the polarization layer 175 . Accordingly, the second adhesive layer 176 may enable adhesion of the protective layer 179 and the polarizing layer 175 disposed on the second adhesive layer 176 . That is, the protective layer 179 may be disposed on the polarization layer 175 and may be adhered to the polarization layer 175 by the second adhesive layer 176 . In this case, the second adhesive layer 176 may be formed of the same material as the first adhesive layer 174 .

The first adhesive layer 174 , the polarizing layer 175 , and the second adhesive layer 176 may form a double OCA structure. The double adhesive structure may be disposed on the organic light emitting device 180 to protect the organic light emitting device 180 from external impact. The first adhesive layer 174 , the polarizing layer 175 , and the second adhesive layer 176 may be integrally formed to form an optical double adhesive structure. At this time, the first adhesive layer 174 is formed thinner than the second adhesive layer 175 , and the polarizing layer 175 disposed between the first adhesive layer 174 and the second adhesive layer 176 is rolled during the manufacturing process. it can be prevented

A wiring (or a connection part) 170 is disposed in the bending area BA. The wiring 170 may be electrically connected to a plurality of pixels disposed in the display area AA. In this case, the wiring 170 may transmit a signal (voltage) from the external module (or signal supply circuit unit) 171 to the display area AA.

The wiring 170 may be formed of the same material as the conductive element disposed in the display area AA. For example, as shown in FIG. 2 , the wiring 170 may be formed of the same material as the gate electrode 134 , but is not limited thereto and is formed of the same material as the source electrode 132 and the drain electrode 133 . can be

The wiring 170 may be surrounded by an insulating material for protecting the wiring 170 . Specifically, the wiring 170 may be surrounded by a film for protecting the wiring 170 . For example, as shown in FIG. 2 , the substrate 110 is provided under the wiring 170 , and an interlayer insulating layer 115 may be formed to surround the upper portion and the side of the wiring. Accordingly, a phenomenon in which the wiring 170 reacts with moisture and corrodes can be prevented.

When the organic light emitting diode display 100 includes the planarization layer 113 , the wiring 170 may be disposed in the bending area BA in a one-layer structure in which the planarization layer 113 is not disposed. In this case, a large amount of space is required to form a specific number of wirings 170 . In order to form the wiring 170 , a conductive material is deposited on the bending area BA, and then the conductive material is patterned in the shape of the wiring 170 to be formed through a process such as etching. Since there is a limit in the fineness of , there is a limit in narrowing the gap between the wiring 170 and the wiring 170 . In addition, since the insulating layers surrounding the wirings 170 must also be patterned, the gap between the wirings 170 cannot be narrowed by more than a specific interval. Accordingly, since a large amount of space is required to form the wiring 170 in the bending area BA, the area of the non-display area NA is increased, and thus it may be difficult to implement the narrow bezel.

In addition, when a single wire 170 is used to transmit one signal, if the corresponding wire 170 is cracked (or broken), the corresponding signal may not be transmitted. As described above, since the wiring 170 is disposed in the bending area BA, the wiring 170 itself may be cracked in the process of bending the substrate 110 . In addition, since the material constituting the film protecting the wiring 170 rather than the conductive material constituting the wiring 170 is, for example, an inorganic material, it may be more vulnerable to stress due to bending. Accordingly, cracks generated in the film surrounding the wiring 170 by stress caused by bending may propagate to the wiring 170 . As such, when the wiring 170 is cracked, a signal may not be transmitted through the wiring 170 or a desired signal may not be transmitted because the resistance of the wiring 170 is greatly increased.

In addition, if a plurality of wirings 170 are used to transmit one signal in the one-layer structure, the area occupied by the wirings 170 in the non-display area NA increases. For example, when two wirings 170 having preliminary wirings are used to transmit one signal, the area occupied by the wirings 170 is doubled. Accordingly, the area occupied by the wiring 170 per unit area in the bending area BA may increase. Accordingly, when the substrate 110 corresponding to the bending area BA is bent, the stress applied to the wiring 170 may increase. Accordingly, in the one-layer structure, it is very difficult to prepare for cracks in the wiring 170 .

In addition, in the one-layer structure including only one planarization layer 113 in the display area AA of the organic light emitting diode display 100 , the scan line SL is disposed in the display area AA as well as the bending area BA. , and various signal lines such as data lines are highly likely to be implemented as one layer. That is, in the display area AA, various driving elements such as the thin film transistor 130 and the storage capacitor 120 are disposed, and the scan line SL, the source electrode 132 and the scan line SL made of the same material as the gate electrode 134 and Data lines made of the same material as the drain electrode 133 are closely arranged. Accordingly, since it is not easy to apply a multilayer structure in which the scan line SL and the data line are disposed on different layers by applying at least two planarization layers, the resistance of various signal lines such as the scan line SL and the data line is reduced. It is very difficult to reduce.

In addition, in order to increase the capacitance of the storage capacitor 120 , it is preferable to implement the storage capacitor 120 in a structure in which a plurality of capacitors are connected in parallel to each other. However, in order to connect the storage capacitors 120 in parallel, a plurality of electrodes disposed to overlap each other are required. In order to secure the plurality of electrodes, a multilayer structure must be secured. In this case, since various driving elements and signal lines are already closely arranged in the display area AA, and the number of conductive layers that can be used is limited, it is very difficult to secure an extra conductive layer.

In addition, in the process of bending the substrate 110 , a tensile force may be applied to the interlayer insulating layer 115 so as to surround the wiring 170 in the bending area BA and upper and side portions of the wiring 170 . have. At this time, the wiring 170 and/or the interlayer insulating layer 115 are pulled in the bending area BA by the tensile force, and bending stress is applied, and the wiring 170 and/or the interlayer insulating layer 115 are cracked. it is likely to be

Hereinafter, in order to describe cracks in the wiring 170 and/or the interlayer insulating layer 115 , reference is made to FIG. 3 first.

3 is a schematic cross-sectional view illustrating compressive and tensile forces applied to layers respectively disposed above and below a neutral plane when the organic light emitting diode display is bent.

3 , a first layer L1 is disposed on an upper surface of the support layer M, a second layer L2 is disposed on a lower surface of the support layer M, and a first layer L1 and a second layer L2 are disposed on the lower surface of the support layer M for convenience of explanation. It is assumed that the second layer L2 is formed of the same material and the same thickness. The support layer M illustrated in FIG. 3 may correspond to the substrate 110 , and the first layer L1 or the second layer L2 may correspond to any one of the wiring 170 and the interlayer insulating layer 115 . .

The neutral plane (NP) refers to a virtual plane in which a compressive force and a tensile force applied to the structure cancel each other out and do not receive stress when the structure is bent. As described above, the first layer (L1) is disposed on the upper surface of the support layer (M), the second layer (L2) is disposed on the lower surface of the support layer (M), and both ends of the support layer (M) are lowered and the support layer ( Assuming that the support layer (M) is bent in a shape in which the central portion of M) is raised, as shown in FIG. 3, the first layer (L1) disposed on the upper surface of the support layer (M) is stretched and thus receives a tensile force, Since the second layer L2 disposed on the lower surface of the support layer M is compressed, it receives a compressive force. In addition, the neutral plane NP is disposed on the support layer M, which is a central portion in the structure in which the first layer L1, the support layer M, and the second layer L2 are stacked. That is, when the other side of the support layer M is bent downward in a state in which one side of the support layer M is fixed, the first layer L1 positioned above the neutral plane NP receives a tensile force and the neutral plane NP receives a tensile force. ) The second layer (L2) located below receives a compressive force. However, the wiring 170 and/or the interlayer insulating layer 115 may be subjected to bending stress when receiving a tensile force among compressive and tensile forces of the same magnitude. Accordingly, since the wiring and the interlayer insulating layer are more vulnerable to tensile force, the first layer L1 is more likely to be cracked than the second layer L2 under the premise that the distance from the neutral plane NP is the same.

Therefore, in order to relieve the bending stress applied to the wiring 170 and/or the interlayer insulating layer 115 disposed in the bending area BA, the wiring and/or the interlayer insulating layer does not receive a tensile force, or even if the tensile force is applied thereto. It is very important to optimize the neutral plane (NP) to minimize the magnitude of the force. Accordingly, it is necessary to design the organic light emitting diode display such that the wiring 170 and/or the interlayer insulating layer 115 are disposed below the neutral plane NP.

Accordingly, as shown in FIG. 2 , the cover film (or the neutral plane raising film) 150 may be applied to the bending area BA. The cover film 150 may be positioned on the interlayer insulating layer 115 in the bending area BA. The cover film 150 may be disposed adjacent to a cross-section of one side having a concave shape of the first adhesive layer 174 . In this case, a cross-section of one side having a concave shape of the first adhesive layer 174 and a cross-section of one side of the cover film 150 may face and correspond to each other. Also, the cover film 150 may be disposed to correspond to the entire bending area BA. Accordingly, the cover film 150 may be disposed between the double adhesive structure and the pad 195 in the bending area BA.

The cover film 150 may include at least one adhesive layer 152 and a coating layer (or a first coating layer) 153 . At least one adhesive layer 152 and the coating layer 153 of the cover film 150 may be sequentially stacked. In this case, the cross-section of one side of the adhesive layer 152 and the coating layer 153 may face and correspond to the cross-section of one side having a concave shape of the first adhesive layer 174 .

The adhesive layer 152 provided in the cover film 150 may cover the wiring 170 and the interlayer insulating layer 115 positioned at a portion corresponding to the bending area BA of the substrate 110 . Accordingly, the adhesive layer 152 may seal the wiring 170 disposed in the bending area BA.

The coating layer 153 may be disposed on the adhesive layer 152 . In this case, the coating layer 153 may be attached to the adhesive layer 152 to protect the adhesive layer 152 . Accordingly, the cover film 150 may protect the wiring 170 disposed in the bending area BA and prevent moisture and oxygen from penetrating into the wiring 170 located in the bending area BA.

Also, the cover film 150 may optimize the neutral plane NP in the bending area BA. As described above, when a specific component receives a tensile force among compressive and tensile forces of the same magnitude, it may be subjected to bending stress and may be more susceptible to cracking. Therefore, as shown in FIG. 2 , it is preferable that both the wiring 170 and the interlayer insulating layer 115 covering the upper and side surfaces of the wiring 170 are disposed below the neutral plane NP. In order to arrange the neutral plane NP as described above, the thickness and constituent material of the cover film 150 are determined.

First, in order for the neutral plane NP to be disposed as shown in FIG. 2 , the thickness of the cover film 150 may be determined. As the thickness of the cover film 150 disposed on the interlayer insulating layer 115 increases, the neutral plane NP increases. Accordingly, in order for the neutral plane NP to be positioned on the interlayer insulating layer 115 , the thickness of the cover film 150 may be configured to have a large value. In this case, when the thickness of the cover film 150 is too thick, a problem may occur during the system fastening process of the organic light emitting diode display. In addition, when the thickness of the cover film 150 is too thin, the neutral plane NP may not be disposed on the interlayer insulating layer 115 . Accordingly, the thickness of the cover film 150 may be determined in consideration of the above description.

In addition, in order to arrange the neutral plane NP as shown in FIG. 2 , the constituent materials of the adhesive layer 152 and the coating layer 153 constituting the cover film 150 may be determined. The adhesive layer 152 and the coating layer 153 may be made of an organic material to be implemented to have the above-described thickness. In this case, the adhesive layer 152 may be formed of, for example, one of acryl, urethane, and acrylic urethane, and the coating layer is polyethylene or polyethylene terephthalate. terephthalate).

In addition, one important factor determining the position of the neutral plane NP is the Young's modulus of the material constituting the cover film 150 . The Young's modulus is a value indicating the ductility of a material, and is an intrinsic property of a material indicating the degree of resistance to tension or compression of the material. When the Young's modulus of a specific material is high, it is difficult to deform the shape because the resistance to tension and compression is large. As the Young's modulus of the constituent material of the cover film 150 increases, the position of the neutral plane NP may move upward of the wiring 170 .

In addition, when the Young's modulus of the constituent material of the cover film 150 is excessively large, the cover film 150 itself may be cracked during the bending process. Also, when the Young's modulus of the material constituting the cover film 150 is too small, the neutral plane NP may not be disposed on the interlayer insulating layer 115 . That is, when the Young's modulus of the material constituting the cover film 150 is too small and the neutral plane NP is disposed under the wiring 170 and the interlayer insulating layer 115 , the wiring 170 and the interlayer insulating layer 115 are neutral. Since it is disposed on the surface NP, it may receive a tensile force, and thus may receive bending stress. Accordingly, the wiring 170 and/or the interlayer insulating layer 115 may be cracked. Accordingly, while the neutral plane NP is disposed on the wiring 170 and the interlayer insulating layer 115 , the constituent material of the cover film is formed such that the cover film 150 has a Young's modulus value that is not damaged due to the increase in Young's modulus. can be decided. For example, in this case, the cover film 150 may be made of a material having a Young's modulus of 1 to 300 Mpa. That is, the cover film 150 may be made of a material having a relatively high Young's modulus.

When the neutral plane NP is disposed on the wiring 170 and the interlayer insulating layer 115 as shown in FIG. 2 by adjusting the thickness d and constituent materials of the cover film 150 as described above All of the interconnections disposed in the bending area BA as well as the interlayer insulating layer 115 made of an inorganic material are disposed under the neutral plane NP. That is, the cover film 150 may be a planarization film that positions the neutral plane NP on the wiring 170 and the interlayer insulating layer 115 when the substrate 110 is bent. Accordingly, since both the wiring 170 and the interlayer insulating layer 115 receive a compressive force during bending, the bending stress of the wiring 170 and the interlayer insulating layer 115 in the bending area BA may be relieved. Accordingly, the occurrence of cracks in the wiring 170 and the interlayer insulating layer 115 may be reduced.

In this case, in the process of bending the substrate 110 , between the concave side of the cover film 150 and the first adhesive layer 174 , a gap between the adhesive layer 152 of the cover film 150 and the substrate 110 may be partially separated. have. That is, a gap between the adhesive layer 152 of the cover film 150 and the substrate 110 may be lifted between the cover film 150 and the concave side of the first adhesive layer 174 . In this case, portions of the wiring 170 and the interlayer insulating layer 115 disposed on the substrate 110 may be exposed to the outside. Accordingly, the exposed wiring may react with moisture and oxygen to cause corrosion.

Therefore, it is very important to prevent a gap between the adhesive layer 152 of the cover film 150 and the substrate 110 from being exposed in the process of bending the substrate 110 , thereby exposing the wiring and/or the interlayer insulating layer.

2 , the organic light emitting diode display 100 may include a first member 177 . The first member (or first filling member) 177 may be disposed between the first adhesive layer disposed under the polarization layer 175 and the cover film 150 . In this case, a cross-section of one side of the first adhesive layer 174 has a concave shape. The concave end surface of the first adhesive layer 174 may be disposed to face the end surface of the one side of the cover film. Accordingly, there may be a space accommodating the first member 177 between the first adhesive layer 174 and the cover film 150 . Accordingly, the first member 177 may fill a space between the cover film 150 and the first adhesive layer 174 configured to have a concave cross-section. In this case, the first member 177 may cover a portion of the wiring and/or a portion of the interlayer insulating layer in the space between the first adhesive layer 174 and the cover film 150 . Accordingly, the first member 177 is formed between a portion of the wiring 170 and/or the interlayer insulating layer 115 between the cover film 150 and the concave side of the first adhesive layer 174 when the substrate 110 is bent. Some of them can be prevented from being exposed.

In order to fill the first member 177 between the first adhesive layer 174 and the cover film 150 , a material constituting the first member 177 may be excessively applied in a liquid state. In this case, the first member 177 may cover a portion of the cover film 150 . In addition, the first member 177 may cover one side of the polarization layer 175 by riding up one side of the polarization layer 175 on the first adhesive layer 174 . Also, the first member 177 may be accommodated in a concave space on one side of the second adhesive layer 176 on the polarization layer 175 due to the phenomenon of climbing up one side of the polarization layer 175 . Accordingly, at least a portion of the first member 177 may be filled in the concave side of the second adhesive layer 176 . Accordingly, the excessively applied material constituting the first member 177 overflows, thereby minimizing the occurrence of defects in the manufacturing process of the organic light emitting display device 100 .

In addition, the first member 177 may arrange the wiring 170 and the interlayer insulating layer 115 in the space between the first adhesive layer 174 and the cover film 150 under the neutral plane NP. At this time, in the space between the first adhesive layer 174 and the cover film 150 , the wiring 170 and the interlayer insulating layer 115 receive a compressive force during bending. Accordingly, the first member 177 may relieve bending stress between the first adhesive layer 174 and the cover film 150 . Accordingly, the occurrence of cracks in the wiring 170 and the interlayer insulating layer 115 in the space between the first adhesive layer 174 and the cover film 150 may be reduced.

The first member 177 covers a portion of the wiring 170 and/or a portion of the interlayer insulating layer 115 , and places the neutral plane NP on the interlayer insulating layer 115 , thereby forming the bending region BA. ), a material of which crack generation is reduced may be determined as a constituent material of the first member 177 . Accordingly, the first member 177 may be an organic material (or an organic member) having a Young's modulus value sufficient to not be damaged due to an increase in Young's modulus. For example, the first member 177 may be formed of one of an acryl-based material or urethane acrylate to cover a portion of the wiring 170 and/or the interlayer insulating layer 115 .

In detail, since the cross-section of the first adhesive layer 174 is concave, there is an advantage in helping to facilitate the filling of the first member 177, and since the cross-section of the second adhesive layer 176 is also concave. , there is an advantage that the first member 177 can easily cover a portion of the cross section of the second adhesive layer 176 . However, the present invention is not limited thereto, and only the cross section of at least one of the first adhesive layer 174 and the second adhesive layer 176 may be concavely formed. In other words, at least one of the first adhesive layer 174 and the second adhesive layer 176 constituting the optical double adhesive structure has an end surface that is concave compared to the end surface of the polarizing layer 175, so that the first member (177) can be accommodated. Therefore, the first member 177 may be filled between the end of the optical double adhesive structure including the first adhesive layer 174 , the polarizing layer 175 , and the second adhesive layer 176 and one end of the cover film 150 . .

As described above with reference to FIG. 1 , the pad 195 is located in the non-display area NA of the substrate 110 and may be located at an end of the substrate 110 . Specifically, the pad 195 may be disposed in the non-display area NA extending to one side from the bending area BA of the substrate 110 . In this case, the pad 195 may enable electrical connection of the external module 171 . Accordingly, an external module (or a signal supply circuit part or a circuit part) 171 may be disposed on the pad 195 disposed on one side of the substrate 110 .

The pad 195 may be configured to include a gate insulating layer 112 , a wiring 170 , and an interlayer insulating layer 115 . A gate insulating layer 112 may be disposed on the substrate 110 , and a wiring 170 may be disposed on the gate insulating layer 112 . In this case, the wiring 170 may extend from the bending area BA to the pad 195 . Accordingly, a portion of the wiring 170 may be positioned on the substrate 110 .

The wiring 170 may be covered with an interlayer insulating layer 115 . In this case, the interlayer insulating layer 115 may include a contact hole, and the wiring 170 may be electrically connected to the external module 171 through the contact hole.

The external module 171 is electrically connected to the wiring 170 , and may supply a signal to the display area AA through the wiring 170 . In this case, various IC chips may be disposed on the external module 171 .

The external module 171 may face and correspond to one side of the cover film 150 . In this case, in the process of bending the substrate 110 , a portion between the adhesive layer 152 of the cover film 150 and the substrate 110 may be separated between one side of the cover film 150 and the external module 171 . . That is, a gap between the adhesive layer 152 of the cover film 150 and the substrate 110 may be lifted between one side of the cover film 150 and the external module 171 . In this case, portions of the wiring 170 and the interlayer insulating layer 115 disposed on the substrate 110 may be exposed to the outside. Accordingly, the exposed wiring 170 may react with moisture, oxygen, and the like and corrode. Therefore, it is very important to prevent the wiring 170 and the interlayer insulating layer 115 from being exposed when the adhesive layer 152 of the cover film 150 and the substrate 110 float in the process of bending the substrate 110 . do.

As shown in FIG. 2 , the organic light emitting diode display 100 may include a second member 178 . The second member (or second filling member) 178 may be disposed between the cover film 150 and the external module 195 . In this case, the second member 178 may fill a space between the cover film 150 and the external module 195 . In this case, the second member 178 may cover a portion of the wiring and a portion of the interlayer insulating layer in the space between the cover film 150 and the external module 195 . Accordingly, the second member 178 may prevent a portion of the wiring and a portion of the interlayer insulating layer from being exposed between the cover film 150 and the external module 195 when the substrate 110 is bent. In other words, the second member may be filled between the pad 195 and one end of the cover film 150 on which the first member 177 is positioned and opposite the other end. In this case, the second member 178 may be formed of the same material and organic material (or organic member) as the first member 177, or may be formed in the same manner.

4 is a cross-sectional view of a cover film applied to an organic light emitting display device according to an exemplary embodiment of the present invention. The cover film 450 shown in Fig. 4 is a cross-sectional view before the cover film 450 is attached to the organic light emitting diode display 100. Therefore, the cover film 450 shown in Fig. 4 is formed by removing the second coating layer 451. When the structure is the same as that of the adhesive layer 152 and the coating layer 153 of the cover film 150 shown in FIG. 2 in structure and design, a redundant description will be omitted.

4 , the cover film 450 includes an adhesive layer (a first adhesive layer) 152 , a first coating layer 153 , and a second coating layer 451 . The adhesive layer 152 is disposed between the first coating layer 153 and the second coating layer 451 .

The second coating layer 451 may be disposed on the lower surface of the adhesive layer 152 . In this case, the second coating layer 451 may be attached to the adhesive layer 152 to protect the adhesive layer 152 before the adhesive layer 152 is attached to the organic light emitting diode display 100 .

The adhesive layer 152 may have different adhesive strength between the top and bottom surfaces. The adhesive strength of the upper surface of the adhesive layer 152 to be adhered to the first coating layer 153 and the lower surface of the adhesive layer 152 to be adhered to the second coating layer 451 may be different. In this case, the adhesive force of the upper surface of the adhesive layer 152 may be greater than the adhesive force of the lower surface of the adhesive layer 152 . Therefore, when a force is applied to remove the second coating layer 451 , the first coating layer 153 is not removed but is adhered to the adhesive layer 152 , and only the second coating layer 451 may be removed. In this case, the second coating layer 451 may be formed of the same material as the first coating layer 153 . For example, the second coating layer 451 may be formed of one of polyethylene and polyethylene terephthalate.

5 is a cross-sectional view of another cover film applied to an organic light emitting diode display according to another exemplary embodiment. The cover film 550 illustrated in FIG. 5 is a cross-sectional view before the cover film is attached to the organic light emitting diode display 100 . The cover film 550 shown in FIG. 5 is the same as that of the cover film 450 shown in FIG. 4 except that it further includes a second adhesive layer 552 and a support layer 554 , and thus a redundant description will be omitted.

5 , the cover film 550 includes an adhesive layer 152 , a second adhesive layer 552 , a first coating layer 153 , a second coating layer 451 , and a support layer 554 . .

The second adhesive layer 552 may be disposed between the first coating layer 153 and the support layer 554 . Accordingly, the support layer 554 may be disposed between the adhesive layer 152 and the second adhesive layer 552 .

The upper surface of the second adhesive layer 552 , the lower surface of the second adhesive layer 552 , and the upper surface of the first adhesive layer 152 may have the same adhesive strength. The lower surface of the first adhesive layer 152 may have different adhesive strength. Specifically, in the adhesive layer 152 under the support layer 554 , the adhesive force of the lower surface in contact with the second coating layer 451 is the upper surface of the adhesive layer 152 , the lower surface of the adhesive layer 152 and the second adhesive layer 552 ). It may be the lowest compared to the adhesive force of the upper surface. Therefore, when a force is applied to remove the second coating layer 451 , the first coating layer 153 is not removed but is adhered to the adhesive layer 152 adhered to the upper portion of the support layer 554 . In this case, only the second coating layer 451 adhering to the second adhesive layer 552 adhering to the lower portion of the support layer 554 may be removed. Support layer 554, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polysilane (polysilane), polysiloxane (polysiloxane), polysilazane (polysilazane), polycarbosilane (polycarbosilane), Polyacrylate, polymethacrylate, polymethylacrylate, polymethylmethacrylate, polyethylacrylate, polyethylmethacrylate, between Click Olefin Copolymer (COC), Cyclic Olefin Polymer (COP), Polyethylene (PE), Polypropylene (PP), Polyimide (PI), Polymethylmethacrylate (PMMA), Polystyrene (PS), Polyacetal ( POM), polyether ether ketone (PEEK), polyester sulfone (PES), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polycarbonate (PC), polyvinylidene fluoride (PVDF), purple It may be formed of one material selected from the group consisting of fluoroalkyl polymer (PFA), styrene-acrylnitrile copolymer (SAN), and combinations thereof.

The support layer 554 may be disposed between the second adhesive layer 552 disposed on the top and the adhesive layer 152 disposed on the bottom to increase the thickness and hardness of the cover film 550 . Accordingly, the cover film 550 may protect the wiring 170 disposed in the bending area BA, and may prevent moisture and oxygen from penetrating into the wiring 170 disposed in the bending area BA.

FIG. 6 is a cross-sectional view illustrating a structure of the organic light emitting diode display shown in FIG. 2 in a final bent state. In FIG. 6 , the encapsulation unit 140 , the cover film 150 , the first adhesive layer 174 , the polarizing layer 175 , and the second adhesive layer 176 among various components disposed on the substrate 110 for convenience of explanation. ), the first member 177 and the second member 178, and only the protective layer 179 is shown.

The encapsulation unit 140 is disposed on the substrate 110 . The encapsulation unit 140 is a component for protecting various components of the organic light emitting diode display 100 , and may be disposed to correspond to at least the display area A/A of the organic light emitting display apparatus 100 .

A first adhesive layer 174 may be disposed between the substrate 110 and the polarization layer 175 , and the first adhesive layer 174 may serve to fix the polarization layer 175 on the substrate 110 . A second adhesive layer 176 may be disposed between the protective layer 179 and the polarizing layer 175 , and the second adhesive layer 176 may serve to fix the protective layer 179 on the polarizing layer 175 . have. In this case, the first member 177 may be formed to cover one side of the first adhesive layer 174 , the polarizing layer 175 , and the second adhesive layer 176 .

A back plate 191 is disposed under the substrate 110 . When the substrate 110 is made of a plastic material such as polyimide (PI), the organic light emitting display device 100 manufacturing process proceeds in a situation where a support substrate made of glass is disposed under the substrate 110 , and the organic light emitting display After the device 100 manufacturing process is completed, the support substrate may be released. However, since components for supporting the substrate 110 are required even after the supporting substrate is released, the back plate 191 for supporting the substrate 110 may be disposed under the substrate 110 . The back plate 191 may be disposed adjacent to the bending area B/A in another area of the substrate 110 except for the bending area B/A. The back plate 191 may be made of a plastic thin film formed of polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), other suitable polymers, combinations of these polymers, or the like.

A support member 193 may be disposed between the two back plates 191 , and the support member 193 may be adhered to the back plate 191 by an adhesive layer 192 . The support member 193 may be formed of a plastic material such as polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), other suitable polymers, combinations of these polymers, or the like. . The strength of the support member 193 formed of these plastic materials may be controlled by providing additives to increase the thickness and/or strength of the support member 193 . The support member 193 may be formed in a desired color (eg, black, white, etc.). Additionally, the support member 193 may be formed of glass, ceramic, metal or other rigid materials or combinations of the foregoing materials.

As described above with reference to FIG. 1 , the external module 171 may be disposed on a pad disposed on one side of the substrate 110 . Various IC chips 194 may be disposed on the external module 171 . Also, the second member 178 may be disposed to cover one side of the external module 171 . Accordingly, in the organic light emitting diode display in the final bent state, the substrate 110 is bent in the non-display area, and the external module 171 connected to the pad is connected to the polarization layer 175 with the display area of the substrate 110 interposed therebetween. may be opposite. In this case, the organic light emitting diode display includes an optical double adhesive structure including a first adhesive layer 174 , a polarizing layer 175 , and a second adhesive layer 176 , a cover film 150 , a first member 177 , and a second filling and second adhesive layer. A specific bending curvature characteristic may be secured by filling the member 178 .

Although the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made within the scope without departing from the technical spirit of the present invention. Therefore, 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. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention should be construed by the 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
110: substrate
120: storage capacitor
130: thin film transistor
140: encapsulation unit
150, 450, 550: cover film
170: wiring
174: first adhesive layer
175: polarizing layer
176: second adhesive layer
177: first member
178: second member
180: organic light emitting device

Claims (21)

a flexible substrate including a display area and a bending area extending from at least one side of the display area;
a plurality of pixels provided in the display area;
a first adhesive layer configured to cover the plurality of pixels, wherein a cross-section of one side corresponding to the bending region has an inwardly concave shape;
a polarizing layer disposed on the first adhesive layer;
a cover film disposed adjacent to one concave side of the first adhesive layer and configured to relieve bending stress in the bending region; and
and a first member configured to fill a space between the cover film and the first adhesive layer configured to have a concave cross-section. delete The method of claim 1,
The electroluminescent display device, which is disposed in the bending region and further includes a connection part electrically connected to the plurality of pixels, wherein the cover film is positioned on the connection part to cover the connection part. 4. The method of claim 3,
The cover film is a planarization film for positioning a neutral plane on the connection part when the substrate is bent. 5. The method of claim 4,
The cover film is composed of one surface and at least one adhesive layer having different adhesive strengths of the one surface and the other surface corresponding to the one surface, the electroluminescent display device. 6. The method of claim 5,
The cover film further includes a support layer between the plurality of adhesive layers. 6. The method of claim 5,
The adhesive layer is made of one of acryl, urethane, and acrylic urethane. 6. The method of claim 5,
The electroluminescent display device, characterized in that the Young's modulus of the cover film is 1 to 300 Mpa. 4. The method of claim 3,
The first member may prevent a portion of the connection portion from being exposed between the cover film and the concave side of the first adhesive layer when the substrate is bent. 10. The method of claim 9,
The first member may be formed of one of acryl and urethane acrylate to cover a part of the connection part. The method of claim 1,
The electroluminescent display device further includes a protective layer disposed on the polarizing layer and a second adhesive layer disposed between the protective layer and the polarizing layer;
A cross section of one side of the second adhesive layer has a concave shape and corresponds to the concave side of the first adhesive layer. 12. The method of claim 11,
The first member may be at least partially filled in a concave side of the second adhesive layer. 4. The method of claim 3,
The electroluminescent display device may further include a circuit part connected to the connection part and a second member positioned between the circuit part and the cover film. 14. The method of claim 13,
The second member may cover a portion of the connection part between the cover film and one side of the circuit part. a flexible substrate having a display area and a non-display area;
a polarizing layer positioned on the display area of the flexible substrate;
a first adhesive layer on a lower surface of the polarizing layer and enabling adhesion to the flexible substrate; and
and a second adhesive layer on the upper surface of the polarizing layer and enabling adhesion to the cover glass (CG) thereon;
The first adhesive layer, the polarizing layer, and the second adhesive layer form an optical double adhesive (Double OCA) structure,
At the end of the optical double adhesive structure, at least one of the first adhesive layer and the second adhesive layer has an end surface that is concave compared to the end surface of the polarizing layer to accommodate an organic member filled in the concave shape, ,
An electroluminescent display device that does not require a barrier film for preventing moisture permeation between the flexible substrate and the polarizing layer due to the first adhesive layer. delete 16. The method of claim 15,
The electroluminescent display device further comprising: a pad in the non-display area, located at an end of the flexible substrate, and enabling electrical connection with a signal supply circuit. 18. The method of claim 17,
The electroluminescent display device of claim 1, further comprising a neutral plane raising film in the non-display area between the pad part and the optical double adhesive structure. 19. The method of claim 18,
The organic member is filled between an end of the optical double adhesive structure and one end of the neutral plane-raising film, and between the opposite end of the neutral plane-raising film and the pad part. delete 20. The method of claim 19,
In the non-display area, the flexible substrate has a bending shape and the signal supply circuit part connected to the pad part is positioned opposite the polarization layer with the display area interposed therebetween, the optical double adhesive structure and the neutral plane An electroluminescent display device in which a specific bending curvature characteristic is secured by filling a rising film and the organic member.

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