Display device

Abstract

To provide a display apparatus that can reduce the stress applied to a signal line in a bendable area of a display panel.SOLUTION: Disclosed is a display apparatus including: a display panel including a display area and a non-display area surrounding the display area, wherein the non-display area has a bendable area; a first backplate supporting the display area of the display panel; and a second backplate spaced apart from the first backplate and supporting a portion of the non-display area, wherein the display panel includes: an adhesive buffer layer disposed on the substrate in an entirety of each of the display area and the non-display area; and first signal lines disposed on the adhesive buffer layer and extending across the bendable area, wherein the adhesive buffer layer is disposed on an upper surface of the substrate in the bendable area.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present specification relates to a display device, and more particularly to a display device capable of reducing stress applied to signal wiring in a bendable region of a display panel while reducing a bezel size. [Background technology]

[0002] Specific examples of flat panel display devices include liquid crystal display devices, organic light emitting display devices, inorganic light emitting display devices, quantum dot display devices, and the like.

[0003] In order to provide a sense of immersion and aesthetics to users, efforts have been made to reduce the width of the non-display area (or bezel area) of a display device that is visible to the user.

[0004] In recent years, flexible display devices including display panels using flexible substrates have been developed, and these have the advantage that they can be designed into various shapes.

[0005] In a flexible display, the width of the non-display area (or bezel area) of the display can be reduced by folding or bending a portion of the non-display area of ​​the display panel so that it is positioned under the display area of ​​the display panel. Summary of the Invention [Problem to be solved by the invention]

[0006] Various signal wiring of the display panel is disposed in the non-display area of ​​the display panel and passes through the bendable area, which is the area where the display panel can be bent.

[0007] In recent years, display devices developed to minimize the bezel area and reduce the thickness of display devices have a narrower bendable area because the bendable area of ​​the display panel is bent with a smaller radius of curvature, which increases stress on the signal wiring, which may cause cracks and breaks in the signal wiring.

[0008] Therefore, a new solution is needed that can reduce the stress on the signal lines in the bendable area of ​​the display panel.

[0009] For this reason, the inventors of the present specification have invented a display device that can reduce the stress applied to the signal wiring in the bendable area of ​​the display panel.

[0010] A problem to be solved by the embodiments of the present specification is to provide a display device that can reduce the bezel area and reduce the stress applied to the signal wiring in the bendable area of ​​the display panel.

[0011] The problems to be solved by the embodiments of this specification are not limited to those mentioned above, and other problems not mentioned can be clearly understood by those of ordinary skill in the art from the description below. [Means for solving the problem]

[0012] A display device according to an embodiment of the present specification includes a display panel including a display area and a non-display area surrounding the display area and having a bendable area, a first backplate supporting the display area of ​​the display panel, and a second backplate spaced apart from the first backplate supporting a part of the non-display area, wherein the display panel includes an adhesive buffer layer disposed on a substrate in the display area and the non-display area, and a first signal wiring disposed on the adhesive buffer layer and passing through the bendable area, and the adhesive buffer layer may be disposed on an upper surface of the substrate in the bendable area.

[0013] In another embodiment, a display device includes a display panel including a first region, a second region, and a bent third region between the first and second regions, a first backplate supporting the first region of the display panel, and a second backplate spaced apart from the first backplate supporting the second region of the display panel, wherein the display panel includes a substrate, an adhesive buffer layer disposed on the substrate in the bent third region of the display panel, and a first signal wiring disposed on the adhesive buffer layer and extending across the bent third region.

[0014] Other specific details of the embodiments are included in the detailed description and drawings.

[0015] According to the embodiment of the present specification, since an adhesive buffer layer having a lower storage modulus than the polymer material of the substrate is disposed between the substrate and the signal wiring in the bendable region of the display panel, when the bendable region of the display panel is bent, slip or shear strain may occur between the substrate and the signal wiring, and stress applied to the signal wiring may be reduced, thereby reducing or preventing cracks and disconnection defects in the signal wiring (RL).

[0016] According to embodiments of the present specification, by maintaining the distance between the edge of the first backplate and the edge of the second backplate at 10 μm or less with the second backplate attached to the underside of the first backplate, stress applied to the signal wiring (RL) can be reduced.

[0017] According to an embodiment of the present specification, the end of the planarization layer in the non-display area is separated from the end of the first backplate by a distance of 60 μm or more, thereby preventing the signal wiring at the end of the planarization layer from being subjected to a stress higher than that applied to the signal wiring in the bendable area.

[0018] The effects of this specification are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. [Brief description of the drawings]

[0019] [Figure 1] FIG. 2 is a plan view showing a display device according to an embodiment of the present disclosure in an unbent state. [Diagram 2] FIG. 2 is a rear view of a display device according to an embodiment of the present disclosure in an unbent state. [Diagram 3] 3 is a cross-sectional view taken along line 3-3 in FIG. 1. [Figure 4] 4 is a cross-sectional view showing a state in which the display device of FIG. 3 is bent. FIG. [Diagram 5] FIG. 4 is a cross-sectional view showing a partial area of ​​FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line 6-6 in FIGS. 1 and 5. [Figure 7] 7 is a cross-sectional view according to one embodiment of the present disclosure showing an area corresponding to the area shown in FIG. 6. [Figure 8] 6 is a cross-sectional view according to one embodiment of the present disclosure showing an area corresponding to the area shown in FIG. 5. [Figure 9] 9 is a cross-sectional view taken along line "9-9" in FIG. 8. [Figure 10] 10 is a cross-sectional view according to one embodiment of the present disclosure showing an area corresponding to the area shown in FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The advantages and features of the present invention, as well as the methods for achieving them, will become apparent from the following detailed description of the embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be embodied in various different forms. However, the present embodiments are provided to complete the disclosure of the present invention and fully convey the scope of the invention to those skilled in the art.

[0021] The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings to explain the embodiments of the present invention are illustrative, and the present invention is not limited to the illustrated matters. The same reference symbols throughout the specification refer to the same components. In addition, when explaining the present invention, if a specific description of related known technology is judged to make the gist of the present invention unclear, the detailed description will be omitted. When "includes," "has," "is," etc. are used as mentioned in this specification, other parts can be added unless "only" is used. When a component is expressed in the singular, it includes the case where it includes a plurality, unless otherwise explicitly stated.

[0022] When interpreting elements, they are interpreted as including a range of error unless otherwise expressly stated.

[0023] When describing the positional relationship between two parts, for example, using "on", "at the top", "below", "to the side", etc., one or more other parts may be located between the two parts, unless "immediately" or "directly" is used.

[0024] Although the terms "first", "second", etc. are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another. Thus, the first component referred to below may be the second component within the technical concept of this specification.

[0025] Like reference numbers throughout the specification refer to like elements.

[0026] The size and thickness of each component shown in the drawings are shown for convenience of explanation, and the present invention is not necessarily limited to the size and thickness of the components shown.

[0027] The features of the various embodiments of the present invention may be combined or combined with each other, either partially or in whole, and may be technically linked and driven in various ways, as will be readily understood by those of ordinary skill in the art, and each embodiment may be implemented independently of each other, or may be implemented together in a linked relationship.

[0028] Hereinafter, a display device according to an embodiment of the present specification will be described in detail with reference to the accompanying drawings.

[0029] Fig. 1 is a plan view showing a display device according to an embodiment of the present specification in an unbent state. Fig. 2 is a rear view showing a display device according to an embodiment of the present specification in an unbent state. Fig. 3 is a cross-sectional view taken along line 3-3 in Fig. 1. Fig. 4 is a cross-sectional view showing the display device of Fig. 3 in a bent state.

[0030] 1 and 2, the display panel 140 of the display device 100 according to the embodiment of the present specification may include a display area (AA) where an image is displayed, and a non-display area (NA) arranged around the display area (AA). The non-display area (NA) may include a bendable area (BA) where the display panel 140 is bent, and a pad part (PD) to which an external driving module is coupled.

[0031] The display panel 140 may be a flexible display panel including a plurality of pixels formed on a flexible substrate. For example, the display device 100 may be a foldable display device in which the display panel 140 can be folded.

[0032] The display area (AA) of the display panel 140 is an area where a plurality of pixels are arranged to display an image. Each pixel may include a plurality of sub-pixels. Each sub-pixel is an individual unit that emits light, and may emit, for example, but not limited to, red, green, blue, or white light. A light emitting element and a pixel circuit unit for driving the light emitting element may be arranged in each sub-pixel of the display area (AA). The pixel circuit unit may include at least one thin film transistor and at least one capacitor. The light emitting element may be, for example, an organic light emitting diode or an inorganic light emitting diode.

[0033] The non-display area (NA) of the display panel 140 is an area where an image is not displayed, and is an area where a driving circuit and various wirings for driving a plurality of sub-pixels arranged in the display area (AA) are arranged. For example, a gate driving circuit may be arranged in the non-display area (NA). The gate driving circuit may be directly formed in the non-display area (NA) of the display panel 140. In one embodiment, a data driving circuit may be further arranged in the non-display area (NA). The data driving circuit may be manufactured as an IC chip and mounted in the non-display area (NA) of the display panel 140, or may be directly formed in the non-display area (NA) of the display panel 140.

[0034] The non-display area (NA) may be an area surrounding the edge of the display area (AA) as shown in Figures 1 and 2. Although the non-display area (NA) is shown surrounding the rectangular display area (AA) in Figures 1 and 2, this is not limited thereto. The display area (AA) and the non-display area (NA) may have a shape suitable for the design of the electronic device in which the display device 100 is mounted. Exemplary shapes of the display area (AA) may be, but are not limited to, a pentagon, a hexagon, a circle, an ellipse, etc.

[0035] A pad section (PD) may be disposed on one side of the non-display area (NA), and the pad section (PD) may be coupled to an external driving module 180. The external driving module may include, for example, a flexible printed circuit board on which a timing controller, a power management IC chip, etc. are mounted.

[0036] The bendable area (BA) is a part of the non-display area (NA) and may be located, for example, on one side of the display area (AA) between the display area (AA) and the pad section (PD). The bendable area (BA) is a part of the non-display area (NA) that can be bent to position the external driving module 180 coupled to the pad section (PD) under the display panel 140.

[0037] The signal wiring (RL) connected to the display area (AA) can be connected to the pad part (PD) through the bendable area (BA) of the non-display area (NA).

[0038] By bending the non-display area (NA) of the display panel 140, when the pad section (PD) of the display panel 140 and the external driving module 180 are disposed below the display panel 140, the size of the non-display area (NA) visible when viewed from above the display panel 140 is reduced, thereby implementing a narrow bezel.

[0039] The backplate 130 is attached to the lower surface of the display panel 140, and is attached to other areas of the display panel 140 except the bendable area (BA) so that the bendable area (BA) of the display panel 140 can be easily bent and has a small radius of curvature. The first backplate 130L and the second backplate 130S are arranged with a distance of the width of the bendable area (BA). The area between the first backplate 130L and the second backplate 130S may correspond to the bendable area (BA). An end of the first backplate 130L in the non-display area (NA) may be one side boundary of the bendable area (BA), and an end of the second backplate 130S facing the end of the first backplate 130L may be the other side boundary of the bendable area (BA). The first backplate 130L supports the display area (AA) and a portion of the non-display area (NA) adjacent to the display area (AA), and the second backplate 130S can support a portion of the non-display area (NA) in which the pad portion (PD) is arranged.

[0040] The first and second back plates 130L and 130S may be made of a polymer film. The polymer film used for the first and second back plates 130L and 130S may be made of, for example, polyimide (PI), polyethylene terephthalate (PET), polycarbonate (PC), or polyethylene naphthalate (PEN), but is not limited thereto.

[0041] 3 and 4, in the display area (AA) of the display panel 140, a polarizing layer 160 may be attached to the upper surface of the display panel 140 by an adhesive layer 155. The polarizing layer 160 is disposed on the display panel 140 to prevent reflection of light entering from the outside and improve the outdoor visibility of the display panel 140. The polarizing layer 160 may include a polarizer and a phase retardation layer.

[0042] A cover window 170 may be attached onto the polarizing layer 160 by an adhesive layer 165 .

[0043] The cover window 170 may be made of impact-resistant and light-transmitting reinforced glass or plastic film to protect the display panel 140 from external impact, moisture, heat, etc. To satisfy strength and folding characteristics, the cover window 170 may be formed to a thickness of 30 to 200 μm.

[0044] When the cover window 170 is made of a plastic film, it may include, but is not limited to, polyimide (PI), polyethylene terephthalate (PET), polypropylene glycol (PPG), and polycarbonate (PC) films.

[0045] If the cover window 170 is made of reinforced glass, the cover window 170 may be broken by external force or stress. At this time, a shatterproof film may be attached to the upper surface of the cover window 170 to prevent fragments of the cover window 170 from scattering. The shatterproof film may include a base film including, for example, polyethylene terephthalate (PET), transparent polyimide (colorless polyimide: CPI), or a laminate of polyethylene terephthalate (PET) and transparent polyimide (CPI). The upper surface of the base film may be coated with a hard coating layer, an anti-reflection layer, an anti-fingerprint layer, etc.

[0046] Adhesive layers 155, 165 may be comprised of a pressure sensitive adhesive, including an optically clear adhesive.

[0047] In the non-display area (AA) of the display panel 140, an external driving module 180 may be coupled to a pad portion (PD) on the top surface of the display panel 140, and a microcoating layer 190 may be disposed covering at least the bendable area (BA).

[0048] The microcoating layer 190 may be disposed in the area between the display area (AA) of the display panel 140 and the external driving module 180 so as to cover the signal wiring (RL) disposed in the non-display area (AA) of the display panel 140.

[0049] The microcoating layer 190 can protect the signal lines (RL) from external impacts while preventing moisture from penetrating into the signal lines (RL). To suppress moisture penetration, one or more getter materials may be mixed into the microcoating layer 190. In addition, the microcoating layer 190 can supplement the rigidity of the display panel 140 in the bendable area (BA) where the backplate is not disposed.

[0050] The microcoating layer 190 can be coated with a predetermined thickness to adjust the position of the neutral plane of the bendable area (BA). By disposing the microcoating layer 190 on the bendable area (BA), the neutral plane can be formed close to the signal wiring (RL). By adjusting the position of the neutral plane of the bendable area (BA) in this manner, it is possible to reduce the stress applied to the signal wiring (RL) when the display panel 140 is bent, and to suppress the occurrence of cracks in the signal wiring (RL).

[0051] One end of the microcoating layer 190 may be in contact with the polarizing layer 160. This can prevent moisture from penetrating into the space between the microcoating layer 190 and the polarizing layer 160, which can cause cracks and breaks in the signal wiring (RL).

[0052] The other end of the microcoating layer 190 may cover a portion of the external driving module 180. This can prevent moisture from penetrating into the space between the external driving module 180 and the pad unit (PD) of the display panel 140, causing cracks and breaks in the signal wiring (RL).

[0053] The microcoating layer 190 is preferably flexible since it is disposed in the non-display area (NA) including the bendable area (BA). The microcoating layer 190 can be formed of, for example, an acrylic resin such as an acrylate polymer, but is not limited thereto.

[0054] A first backplate 130L and a second backplate 130S may be attached to the bottom surface of the display panel 140 by an adhesive layer 135.

[0055] Adhesive layer 135 may be comprised of a pressure sensitive adhesive, including an optically clear adhesive.

[0056] The adhesive member 185 may be disposed on the lower surface of the second backplate 130S. The adhesive member 185 may be a pressure-sensitive adhesive or a double-sided tape.

[0057] As shown in FIG. 4, with the bendable area (BA) of the display panel 140 bent and the external driving module 180 positioned below the display panel 140, the second backplate 130S may be attached and fixed to the underside of the first backplate 130L by an adhesive material 185.

[0058] When the second backplate 130S is attached to the lower surface of the first backplate 130L, the distance (d1) between the adjacent ends of the first backplate 130L and the second backplate 130S is preferably 10 μm or less. This is because the more the distance (d1) between the ends of the first backplate 130L and the second backplate 130S exceeds 10 μm, the more the stress applied to the signal wiring (RL) increases. It is most preferable that the ends of the first backplate 130L coincide with the ends of the second backplate 130S.

[0059] Fig. 5 is a cross-sectional view showing a partial area of ​​Fig. 3. Fig. 6 is a cross-sectional view taken along line "6-6" of Figs.

[0060] 5 and 6, a display device 100 according to an embodiment of the present disclosure may include a display panel 140, a polarizing layer 160, first and second backplates 130L and 130S, and a microcoating layer 190.

[0061] The display panel 140 may include a buffer layer 142 , an adhesive buffer layer 143 , a pixel circuit portion 144 , a planarization layer 145 , an insulating layer 146 , a light emitting element 148 , and an encapsulation layer 149 disposed on a substrate 141 .

[0062] The substrate 141 may include a flexible polymeric material. For example, the substrate 141 may be made of a polymeric material such as polyimide, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyethersulfone, polyarylate, polysulfone, cyclic-olefin copolymer, etc. In one embodiment, the substrate 141 may be a single layer made of polyimide having a thickness of, for example, about 5 μm to 15 μm.

[0063] A buffer layer 142 may be disposed on the substrate 141. The buffer layer 142 can prevent moisture, oxygen, or impurities from penetrating through the substrate 141. The buffer layer 142 may be located in the display area (AA) of the display device 100. The buffer layer 142 may also be partially disposed in the non-display area (NA) of the display device 100, but may not be disposed in the bendable area (BA).

[0064] The buffer layer 142 may be a single layer or multiple layers of an inorganic insulating material, such as, but not limited to, silicon nitride, silicon oxide, or silicon oxynitride.

[0065] An adhesive buffer layer 143 may be disposed on the buffer layer 142. The adhesive buffer layer 143 may be disposed over the entire display area (AA) and non-display area (NA) of the display panel 140. The adhesive buffer layer 143 may be disposed directly on the top surface of the substrate 141 in the bendable area (BA) of the display panel 140.

[0066] The adhesive buffer layer 143 may be made of, for example, an acrylic, silicone, rubber, or polyurethane adhesive material, but is not limited thereto. The adhesive buffer layer 143 may have a lower storage modulus than the polymer material of the substrate 141. In one embodiment, the adhesive buffer layer 143 may have a storage modulus in the range of 0.01 MPa to 1,000 MPa at 25° C. In another embodiment, the adhesive buffer layer 143 may have a storage modulus in the range of 0.01 MPa to 50 MPa at 25° C. The adhesive buffer layer 143 may be disposed with a thickness of 0.5 μm to 3.0 μm.

[0067] A pixel circuit portion 144 may be disposed on the adhesive buffer layer 143 in the display area (AA). The pixel circuit portion 144 can drive and switch a light emitting element 148 disposed in the display area (AA).

[0068] The pixel circuit unit 144 may include at least one thin film transistor and at least one storage capacitor using an amorphous silicon semiconductor, a polycrystalline silicon semiconductor, or an oxide semiconductor. The at least one thin film transistor may include at least one driving thin film transistor and at least one switching thin film transistor. When the pixel circuit unit 144 includes a thin film transistor, it may be formed by a TFT manufacturing process.

[0069] The pixel circuit portion 144 may be provided in a pixel driving chip fabricated using a MOSFET manufacturing process on a single crystal semiconductor substrate. The pixel driving chip may include a plurality of circuit units, and each circuit unit may include at least one driving transistor, at least one switching transistor, and at least one storage capacitor. For example, the pixel driving chip may have a size of 1-500 μm and may be referred to as a microdriver chip. The pixel driving chip may include various input and output pads.

[0070] The planarization layer 145 surrounding the side of the pixel circuit portion 144 may be disposed on the adhesive buffer layer 143 in the display area (AA). In one embodiment, the planarization layer 145 may cover the upper surface of the pixel circuit portion 144. The planarization layer 145 may be partially disposed in the non-display area (NA) of the display device 100, but may not be disposed in the bendable area (BA). An end of the planarization layer 145 may be located closer to the bendable area (BA) than an end of the buffer layer 142. An end of the planarization layer 145 may be spaced apart from the bendable area (BA) by a predetermined distance.

[0071] The end of the planarization layer 145 in the non-display area (NA) is preferably spaced apart from the end of the first backplate 130L by a distance (d2) of 60 μm or more. If the end of the planarization layer 145 is spaced apart from the end of the first backplate 130L by a distance less than 60 μm, a higher stress is applied to the signal wiring (RL) at the end of the planarization layer 145 than the stress applied to the signal wiring (RL) in the bendable area (BA). Therefore, by spaced apart the end of the planarization layer 145 in the non-display area (NA) by a distance of 60 μm or more from the end of the first backplate 130L, it is possible to prevent a higher stress from being applied to the signal wiring (RL) at the end of the planarization layer 145 than the stress applied to the signal wiring (RL) in the bendable area (BA).

[0072] The planarization layer 145 may be made of an organic insulating material, for example, but not limited to, a photosensitive photo acryl or a photosensitive polyimide.

[0073] Signal wiring (RL) may be disposed on the planarization layer 145. The signal wiring (RL) may be disposed in a part of the display area (AA) and in the non-display area (NA) including the bendable area (BA). The signal wiring (RL) may extend from the display area (AA) to the bendable area (BA) and connect to the pad part (PD) in the non-display area (NA) through the bendable area (BA). The signal wiring (RL) may be disposed directly on the adhesive buffer layer 143 in the bendable area (BA).

[0074] The signal wiring (RL) may be made of a single layer or a multi-layer structure of titanium (Ti), tantalum (Ta), aluminum (Al), copper (Cu), molybdenum (Mo), chromium (Cr), nickel (Ni), neodymium (Nd), silver (Ag), gold (Au), etc. The signal wiring (RL) may be made of a three-layer structure of, for example, Ti / Al / Ti.

[0075] An insulating layer 146 covering the signal lines (RL) may be disposed on the planarization layer 145 and the pixel circuit portion 144. The insulating layer 146 may be disposed over the entire display area (AA) and non-display area (NA) of the display panel 140. The insulating layer 146 covers the signal lines (RL) in the bendable area (BA) of the display panel 140 and may be disposed on the adhesive buffer layer 143. The insulating layer 146 may be a single layer, or may include multiple layers.

[0076] The insulating layer 146 may be made of an organic insulating material. The insulating layer 146 may be made of, for example, but is not limited to, a photosensitive photo acryl or a photosensitive polyimide. The insulating layer 146 may be disposed to a thickness of 6 μm to 10 μm.

[0077] By disposing the insulating layer 146 on the bendable area (BA), the position of the neutral plane can be adjusted to be close to the signal wiring (RL). By adjusting the position of the neutral plane of the bendable area (BA) in this manner, it is possible to reduce the stress that the signal wiring (RL) receives when the display panel 140 is bent, and to suppress the occurrence of cracks in the signal wiring (RL).

[0078] At least one light emitting element 148 may be disposed on the insulating layer 146 in the display area (AA).

[0079] At least one connecting electrode penetrating the insulating layer 146 may be disposed between the light emitting element 148 and the pixel circuit unit 144 to connect the light emitting element 148 and the pixel circuit unit 144. When the insulating layer 146 includes multiple layers, there may be multiple connecting electrodes penetrating the multiple layers, respectively.

[0080] A sealing layer 149 that covers the light emitting element 148 may be disposed on the insulating layer 146. The sealing layer 149 may include at least one of an organic insulating material or an inorganic insulating material.

[0081] A polarizing layer 160 may be disposed on the encapsulating layer 149. The polarizing layer 160 may include a polarizer layer and a phase retardation layer.

[0082] A microcoating layer 190 may be disposed on the insulating layer 146 in the non-display area (NA). The microcoating layer 190 may be disposed in the non-display area (NA) so as to cover the bendable area (BA). One end of the microcoating layer 190 may be in contact with the polarizing layer 160.

[0083] In the present embodiment, since an adhesive buffer layer 143 having a lower storage modulus than the polymer material of the substrate 141 is disposed between the substrate 141 and the signal line (RL) in the bendable area (BA) of the display panel 140, when the bendable area (BA) of the display panel 140 is bent, slip or shear strain may occur between the substrate 141 and the signal line (RL) and stress applied to the signal line (RL) may be reduced. Therefore, cracks and disconnection defects of the signal line (RL) may be reduced or prevented.

[0084] FIG. 7 is a cross-sectional view according to one embodiment herein showing an area corresponding to the area shown in FIG.

[0085] 7, unlike FIG. 6, the substrate 141' may include a lower layer 141a, an intermediate layer 141b, and an upper layer 141c. The substrate 141' may have a laminated structure in which the intermediate layer 141b is inserted between the lower layer 141a and the upper layer 141c. The lower layer 141a and the upper layer 141c may be made of a polymer material such as polyimide, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyethersulfone, polyarylate, polysulfone, cyclic-olefin copolymer, etc. The intermediate layer 141b may be a single layer or a multilayer structure of an inorganic material such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), etc. The inorganic material of the intermediate layer 141b prevents gases such as H2O and O2 from penetrating the substrate 141'.

[0086] An adhesive buffer layer 143 may be disposed on the substrate 141', and the signal traces (RL) may be disposed directly on the adhesive buffer layer 143. An insulating layer 146 may be disposed on the adhesive buffer layer 143, covering the signal traces (RL). A microcoating layer 190 may be disposed on the insulating layer 146.

[0087] In the present embodiment, since an adhesive buffer layer 143 having a lower storage modulus than the polymer material of the substrate 141' is disposed between the substrate 141' and the signal line (RL) in the bendable area (BA) of the display panel 140, when the bendable area (BA) of the display panel 140 is bent, slip or shear strain may occur between the substrate 141' and the signal line (RL) and stress applied to the signal line (RL) may be reduced, thereby reducing or preventing cracks and breaks in the signal line (RL).

[0088] Figure 8 is a cross-sectional view according to an embodiment of the present disclosure, showing an area corresponding to the area shown in Figure 5. Figure 9 is a cross-sectional view taken along line "9-9" in Figure 8. In the following, only the differences between this embodiment and the embodiment of Figures 5 and 6 will be described with reference to Figures 8 and 9.

[0089] 8 and 9, a first signal wiring (RL1) and a first insulating layer 146 may be disposed on the planarization layer 145. Then, a second signal wiring (RL2) and a second insulating layer 147 may be disposed on the first insulating layer 146.

[0090] The first signal wiring (RL1) and the second signal wiring (RL2) may be arranged in the non-display area (NA) including a part of the display area (AA) and the bendable area (BA). The first signal wiring (RL1) and the second signal wiring (RL2) can extend from the display area (AA) to the bendable area (BA) and connect to the pad part (PD) of the non-display area (NA) through the bendable area (BA).

[0091] The first signal wiring (RL1) may be disposed directly on the adhesive buffer layer 143 in the bendable area (BA). The second signal wiring (RL2) may be disposed at a position overlapping the first signal wiring (RL1), but is not limited thereto. The second signal wiring (RL2) may be disposed at a position between the first signal wirings (RL1).

[0092] The first signal wiring (RL) and the second signal wiring (RL2) may be made of a single layer or multi-layer structure of titanium (Ti), tantalum (Ta), aluminum (Al), copper (Cu), molybdenum (Mo), chromium (Cr), nickel (Ni), neodymium (Nd), silver (Ag), gold (Au), etc. The signal wiring (RL) may be made of a three-layer structure of Ti / Al / Ti, for example.

[0093] The first insulating layer 146 and the second insulating layer 147 may be disposed over the entire display area (AA) and non-display area (NA) of the display panel 140. The first insulating layer 146 may cover the first signal wiring (RL1) in the bendable area (BA) of the display panel 140 and may be disposed on the adhesive buffer layer 143. The second insulating layer 147 may cover the second signal wiring (RL2) in the bendable area (BA) of the display panel 140 and may be disposed on the first insulating layer 146.

[0094] The second signal wiring (RL2) can transmit the same signal as the corresponding first signal wiring (RL1).

[0095] When one signal wiring is used to transmit one signal, if a crack occurs in the signal wiring, the signal may not be transmitted.

[0096] However, in the bendable area (BA) of the display device 101 according to this embodiment, the first signal wiring (RL1) and the second signal wiring (RL2) are dually arranged, so that even if one signal wiring is broken, signal transmission can be guaranteed.

[0097] In the present embodiment, since the adhesive buffer layer 143 having a lower storage modulus than the polymer material of the substrate 141 is disposed between the substrate 141 and the first signal line (RL1) in the bendable area (BA) of the display panel 140, when the bendable area (BA) of the display panel 140 is bent, slip or shear strain may occur between the substrate 141 and the first signal line (RL1), and stress applied to the first signal line (RL1) and the second signal line (RL2) may be reduced. Therefore, cracks and disconnection defects of the first signal line (RL1) and the second signal line (RL2) may be reduced or prevented.

[0098] FIG. 10 is a cross-sectional view according to one embodiment herein showing an area corresponding to the area shown in FIG.

[0099] 10, unlike FIG. 9, a substrate 141' may include a lower layer 141a, an intermediate layer 141b, and an upper layer 141c. The substrate 141' may have a laminated structure in which the intermediate layer 141b is inserted between the lower layer 141a and the upper layer 141c. The lower layer 141a and the upper layer 141c may be made of a polymer material such as polyimide, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyethersulfone, polyarylate, polysulfone, cyclic-olefin copolymer, or the like. The intermediate layer 141b may be a single layer or a multilayer structure of an inorganic material such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), etc. The inorganic material of the intermediate layer 141b prevents gases such as H2O and O2 from penetrating into the substrate 141'.

[0100] An adhesive buffer layer 143 may be disposed on the substrate 141', and a first signal line (RL1) may be disposed directly on the adhesive buffer layer 143. A first insulating layer 146 may be disposed on the adhesive buffer layer 143, covering the first signal line (RL1). A second signal line (RL2) may be disposed on the first insulating layer 146, and a second insulating layer 147 may be disposed on the second signal line (RL2). A microcoating layer 190 may be disposed on the second insulating layer 147.

[0101] In the bendable area (BA) of the display device 101' according to this embodiment, the first signal wiring (RL1) and the second signal wiring (RL2) are dually arranged, so that signal transmission can be ensured even if one signal wiring is broken.

[0102] In the present embodiment, since the adhesive buffer layer 143 having a lower storage modulus than the polymer material of the substrate 141' is disposed between the substrate 141' and the first signal line (RL1) in the bendable area (BA) of the display panel 140, when the bendable area (BA) of the display panel 140 is bent, slip or shear strain may occur between the substrate 141' and the first signal line (RL1), and stress applied to the first signal line (RL1) and the second signal line (RL2) may be reduced. Therefore, cracks and disconnection defects of the first signal line (RL1) and the second signal line (RL2) may be reduced or prevented.

[0103] A display device according to an embodiment of the present specification can be described as follows.

[0104] A display device according to an embodiment of the present specification includes a display panel including a display area and a non-display area surrounding the display area and having a bendable area, a first backplate supporting the display area of ​​the display panel, and a second backplate spaced apart from the first backplate supporting a part of the non-display area, wherein the display panel includes an adhesive buffer layer disposed on a substrate across the entire display area and the non-display area, and a first signal wiring disposed on the adhesive buffer layer and passing through the bendable area, and the adhesive buffer layer may be disposed on an upper surface of the substrate in the bendable area.

[0105] According to some embodiments herein, the adhesive buffer layer may have a lower storage modulus than the polymeric material of the substrate.

[0106] According to some embodiments herein, the adhesive buffer layer may have a storage modulus at 25°C in the range of 0.01 MPa to 1,000 MPa.

[0107] According to some embodiments herein, the adhesive buffer layer may have a thickness of 0.5 μm to 3.0 μm.

[0108] According to some embodiments herein, the adhesive buffer layer may be comprised of any of an acrylic, silicone, rubber, polyurethane based adhesive material, or combinations thereof.

[0109] According to some embodiments herein, when the bendable region of the display panel is bent and the second backplate is attached to the underside of the first backplate, the distance between adjacent edges of the first backplate and the second backplate may be 10 μm or more.

[0110] According to some embodiments herein, the display panel may further include a pixel circuit portion disposed on the adhesive buffer layer in the display area, and a planarization layer surrounding the sides of the pixel circuit portion.

[0111] According to some embodiments herein, the planarization layer may extend into the non-display area, and an end of the planarization layer in the non-display area may be spaced apart from an end of the first backplate by a distance of 60 μm or more.

[0112] According to some embodiments herein, the display panel may further include a first insulating layer disposed on the adhesive buffer layer over the entire display area and the non-display area and covering the first signal wiring, and a second signal wiring disposed on the first insulating layer and passing through the bendable area.

[0113] According to some embodiments herein, the substrate may be a single layer of polymeric material or a laminated structure having an intermediate layer of inorganic material interposed between a lower layer and an upper layer of polymeric material.

[0114] In another embodiment, a display device includes a display panel including a first region, a second region, and a bent third region between the first and second regions, a first backplate supporting the first region of the display panel, and a second backplate adjacent to the first backplate supporting the second region of the display panel, where the display panel includes a substrate, an adhesive buffer layer disposed on the substrate in the bent third region of the display panel, and a first signal wiring disposed on the adhesive buffer layer and extending across the bent third region.

[0115] Although the embodiments of the present specification have been described in detail above with reference to the attached drawings, the present specification is not necessarily limited to these embodiments, and various modifications are possible within the scope of the technical idea. Therefore, the embodiments disclosed in the present specification are for the purpose of explanation, not for the purpose of limiting the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by these embodiments. [Explanation of symbols]

[0116] 100,101 Display device 130 Backplate 130L 1st Back Plate 130S 2nd back plate 140 Display Panel 160 Polarizing Layer 170 Cover Window 180 External Drive Module 190 micro-coating layers AA display area BA bendable area NA hidden area PD Pad RL signal wiring

Claims

1. a display panel including a display area and a non-display area surrounding the display area and having a bendable area; a first back plate supporting at least the display area of ​​the display panel; a second back plate spaced apart from the first back plate and supporting a portion of the non-display area of ​​the display panel; The display panel includes: A substrate; an adhesive buffer layer disposed on the substrate in the display area and the non-display area; a first signal wiring disposed on the adhesive buffer layer and passing through the bendable region, the adhesive buffer layer being disposed on an upper surface of the substrate in the bendable region; The adhesive buffer layer has a lower storage modulus than the polymeric material of the substrate.

2. 2. The display device according to claim 1, wherein the adhesive buffer layer has a storage modulus of elasticity at 25° C. in the range of 0.01 MPa to 1,000 MPa.

3. The display device according to claim 1 , wherein the adhesive buffer layer has a thickness of 0.5 μm to 3.0 μm.

4. The adhesive buffer layer is made of an acrylic, silicone, rubber, or polyurethane adhesive material, or a combination thereof. The display device according to claim 1 .

5. 2. The display device of claim 1, wherein when the bendable region of the display panel is bent and the second backplate is attached to the underside of the first backplate, the distance between adjacent ends of the first backplate and the second backplate is 10 μm or less.

6. The display device according to claim 1 , wherein the display panel further comprises: a pixel circuit portion disposed on the adhesive buffer layer in the display region; and a planarization layer surrounding a side surface of the pixel circuit portion.

7. 7. The display device of claim 6, wherein the planarization layer extends into the non-display region, and an end of the planarization layer in the non-display region is spaced apart from an end of the first backplate in the non-display region by a distance of 60 μm or more.

8. 2. The display device of claim 1, wherein the display panel further includes a first insulating layer disposed on the adhesive buffer layer across the entire display area and the non-display area and covering the first signal wiring, and a second signal wiring disposed on the first insulating layer and passing through the bendable area.

9. 2. The display device of claim 1, wherein the substrate is a single layer made of a polymeric material or a laminated structure in which an intermediate layer made of an inorganic material is inserted between a lower layer made of a first polymeric material and an upper layer made of a second polymeric material.

10. a display panel including a first region, a second region, and a bendable third region between the first region and the second region; a first back plate supporting the first region of the display panel; a second back plate spaced apart from the first back plate and supporting the second region of the display panel; Here, the display panel is A substrate; an adhesive buffer layer disposed on the substrate in the bendable third region of the display panel; a first signal trace disposed on the adhesive buffer layer and extending across the bendable third region; The adhesive buffer layer has a lower storage modulus than the polymeric material of the substrate.

11. 11. The display device according to claim 10, wherein the adhesive buffer layer has a storage modulus in the range of 0.01 MPa to 1,000 MPa at 25°C.

12. The display device according to claim 10, wherein the adhesive buffer layer has a thickness of 0.5 μm to 3.0 μm.

13. The display device according to claim 10, wherein the adhesive buffer layer is made of an acrylic, silicone, rubber, or polyurethane adhesive material, or a combination thereof.

14. 11. The display device of claim 10, wherein when the bendable third region of the display panel is bent and the second backplate is attached to the lower surface of the first backplate, a distance between adjacent ends of the first backplate and the second backplate is 10 μm or less.

15. The display device of claim 10 , wherein the adhesive buffer layer is disposed over the first region, the second region, and the bendable third region.

16. The display device according to claim 10 , wherein the first region includes a display region of the display panel, and a non-display region of the display panel includes the second region and the third region.

17. the display panel further includes a pixel circuit portion disposed on the adhesive buffer layer in the first region; and a planarization layer surrounding a side surface of the pixel circuit portion; The display device according to claim 10 , wherein the planarization layer extends a distance equal to or greater than 60 μm shorter than the edge of the first backplate.

18. 11. The display device of claim 10, wherein the display panel further includes a first insulating layer disposed on the adhesive buffer layer and covering the first signal wiring, and a second signal wiring disposed on the first insulating layer and passing through the bendable third region.

19. 11. The display device of claim 10, wherein the substrate is a single layer made of a polymeric material or a laminated structure in which an intermediate layer made of an inorganic material is inserted between a lower layer made of a first polymeric material and an upper layer made of a second polymeric material.

20. The display device of claim 10 , wherein the adhesive buffer layer is disposed directly on the substrate in the bendable third region, and the first signal wiring is disposed directly on the adhesive buffer layer.

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