Flexible Display Device

Abstract

To provide a flexible display device which enables a reduction in bezel width.SOLUTION: A flexible display device according to an embodiment disclosed herein a display area and non-display area, the non-display area including a display panel with a bending area, a plurality of light-emitting elements disposed in the display area of the display panel, a plurality of wiring lines disposed in the non-display area of the display panel to extend to the display area, and a reflective layer disposed under the plurality of wiring lines in the non-display area between the display area and the bending area.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present specification relates to a flexible display device, and more particularly, to a flexible display device capable of reducing a bezel width. [Background technology]

[0002] 2. Description of the Related Art As we enter the information age, the field of display devices that visually display electrical information signals is rapidly developing, and research is ongoing to develop various display devices with improved performance, such as thinner, lighter, and less power consumption.

[0003] Representative display devices include liquid crystal display devices (LCDs), field emission display devices (FEDs), electro-wetting display devices (EWDs), and organic light emitting display devices (OLEDs).

[0004] Electroluminescent displays, such as organic light emitting displays, are self-emitting displays that do not require a separate light source, unlike liquid crystal displays, and can be manufactured in a lightweight and thin form. Electroluminescent displays are also advantageous in terms of power consumption due to their low voltage operation, and are also excellent in color realization, response speed, viewing angle, and contrast ratio (CR), and are expected to be used in a variety of fields.

[0005] In an electroluminescence display device, an emissive layer (EML) is placed between two electrodes consisting of an anode and a cathode. When holes from the anode are injected into the emissive layer and electrons from the cathode are injected into the emissive layer, the injected electrons and holes recombine with each other to form excitons in the emissive layer, which emits light.

[0006] The light-emitting layer contains a host material and a dopant material. When the two materials interact with each other, the host generates excitons from electrons and holes and transfers the energy to the dopant. The dopant is a dye-like organic material added in small amounts and receives energy from the host and converts it into light.

[0007] The electroluminescent display is encapsulated with glass, metal or film to prevent moisture or oxygen from entering the inside of the electroluminescent display from the outside, prevent oxidation of the light-emitting layer or electrodes, and protect the display from mechanical or physical shocks applied from the outside. Summary of the Invention [Problem to be solved by the invention]

[0008] As display devices become smaller, efforts are being made to reduce a bezel area, which is an outer periphery of a display area, in order to increase the size of an effective display screen within the same area of ​​the display device.

[0009] However, since wiring and driving circuits for driving the screen are arranged in the bezel area, which corresponds to the non-display area, there is a limit to how much the bezel area can be reduced.

[0010] In recent years, in relation to flexible electroluminescent display devices that can maintain display performance even when warped by using a flexible substrate made of a ductile material such as plastic, attempts have been made to reduce the bezel area by bending the non-display area of ​​the flexible substrate in order to reduce the bezel area while still securing area for wiring and driving circuits.

[0011] An electroluminescent display device using a flexible substrate such as plastic needs to ensure the flexibility of various insulating layers and wiring made of metal materials arranged on the substrate and to prevent defects such as cracks that may occur due to bending.

[0012] The insulating layer and wiring arranged in the bending area have a protective layer, such as a micro coating layer, placed on the wiring and insulating layer in the bending area to prevent cracks, protect the wiring from foreign objects from the outside, and adjust the neutral plane of the bending area by coating it to a certain thickness.

[0013] In recent years, electroluminescent display devices have been developed to minimize the bezel area and to reduce the thickness of the display device, and the bending area of ​​the flexible substrate has an extreme curvature, thereby minimizing the thickness of the microcoating layer.

[0014] In addition, to reduce the bezel area, the outer frame of the flexible display device is formed using UV or heat curing resin instead of the existing metal frame. However, when curing the resin using UV, the resin may get inside the bent flexible display device and not harden. In addition, signal wiring passes through the bezel area, and the resin that has gotten inside the flexible display device may be prevented from hardening by the signal wiring.

[0015] Therefore, the inventors of the present specification have recognized the above-mentioned problems and conducted various experiments to enable the resin for the inner sealing and the outer sealing to be uniformly and completely cured in the bending region. Through various experiments, they have invented a new flexible display device that enables the inner sealant and the outer sealant to be uniformly and completely cured in the bending region.

[0016] An object of the present invention is to provide a flexible display device in which an outer frame can be formed with an outer sealant without defects.

[0017] The problems to be solved by the embodiments of the present specification are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0018] A flexible display device according to an embodiment of the present specification may include a display area and a non-display area, and the non-display area may include a display panel including a bending area, a plurality of light-emitting elements arranged in the display area of ​​the display panel, a plurality of wirings arranged in the non-display area of ​​the display panel and extending into the display area, and a reflective layer arranged under the wirings in the non-display area between the display area and the bending area.

[0019] A method for manufacturing a flexible display device according to an embodiment of the present specification is provided. The flexible display device according to the embodiment of the present specification may include a display panel including a display area and a non-display area including a bending area, and a plurality of light-emitting elements disposed in the display area of ​​the display panel. The method for manufacturing a flexible display device according to the embodiment of the present specification may include forming a plurality of wirings in the non-display area of ​​the display panel, the wirings extending to the display area, and forming a reflective layer under the plurality of wirings in the non-display area between the display area and the bending area.

[0020] Further details of the embodiments are included in the detailed description and the drawings. Effect of the Invention

[0021] The flexible display device according to the embodiment of the present specification provides the effect of reducing the bezel width and improving the aesthetics.

[0022] The flexible display device according to the embodiments of the present specification provides an advantage in that the inner sealant and the outer sealant are cured uniformly and completely in the bending region, thereby preventing assembly defects caused by leakage of uncured resin.

[0023] The flexible display device according to the embodiments of the present disclosure provides an advantage of preventing assembly defects caused by a difference in hardening between the inner sealant and the outer sealant in the bending region without additional processes.

[0024] The effects of the flexible display device according to the embodiments of the present specification are not limited to the exemplified contents, and various other effects are included in the present specification.

[0025] The contents of the specification, which describe the problem to be solved, the means for solving the problem, and the effects described above, do not specify essential features of the claims, and therefore the scope of the claims is not limited by the matters described in the specification. [Brief description of the drawings]

[0026] [Figure 1] 1 is a block diagram of a flexible display device according to an embodiment of the present disclosure; [Diagram 2] 1 is a circuit diagram of a sub-pixel of a flexible display device according to an embodiment of the present disclosure; [Diagram 3] 1 is a plan view of a flexible display device according to an embodiment of the present disclosure; [Figure 4] 1 is a perspective view of a flexible display device according to an embodiment of the present disclosure; [Diagram 5] 1 is a perspective view illustrating a bending state of a flexible display device according to an embodiment of the present disclosure; [Figure 6a] FIG. 4 is a cross-sectional view taken along line II' in FIG. [Figure 6b] FIG. 4 is a cross-sectional view taken along line II-II' in FIG. [Figure 7] 1 is a cross-sectional view of a portion of a flexible display device according to an embodiment of the present specification; [Figure 8] FIG. 8 is a side view of the flexible display device of FIG. [Figure 9] FIG. 13 is a diagram illustrating a part of a cross section of a flexible display device according to another embodiment of the present specification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The advantages and features of the present invention, and the methods for achieving the same, 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, and may be embodied in various different forms. The embodiments are provided solely for the purpose of making the disclosure of the present invention complete and fully conveying the scope of the invention to those skilled in the art to which the present invention pertains.

[0028] The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of this specification are illustrative, and are not limited to the matters illustrated in the drawings. The same reference numerals refer to the same components throughout the specification. In addition, when describing this specification, if it is determined that a specific description of related known technology may unnecessarily obscure the gist of this specification, the detailed description will be omitted. When the terms "include", "have", "be made", etc. are used in this specification, other parts may be added since "only" is not used. When a component is expressed in the singular, it includes the case where it includes a plural, unless otherwise expressly stated.

[0029] When interpreting elements, they are to be interpreted as including an error range even if there is no separate explicit description of the error range.

[0030] When describing a positional relationship, for example when the positional relationship of two parts is described using terms such as "above," "upper," "lower," "next to," etc., one or more other parts may be located between the two parts, unless, for example, "immediately" or "directly" is used.

[0031] When describing a temporal relationship, when the temporal precedence / subsequence relationship is described using the terms "after," "following," "next," "before," etc., it is possible to include cases where things are not consecutive, since the words "immediately" or "directly" are not used.

[0032] Although the terms "first", "second" and the like 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. Therefore, the first component referred to below may be the second component within the technical concept of this specification.

[0033] In describing components in this specification, terms such as first, second, A, B, (a), (b), etc. may be used. Such terms are merely intended to distinguish one component from other components, and do not limit the nature, order, sequence, number, etc. of the components. When a component is described as being "coupled," "connected," or "connected" to another component, it should be understood that the component may be directly connected or connected to the other component, but other components may be "intervening" between each component that may be indirectly connected or connected without any particular explicit description.

[0034] "At least one" should be understood to include all combinations of one or more of the associated components. For example, the meaning of "at least one of a first, second, and third component" includes all combinations of two or more of the first, second, and third components, and not just the first, second, or third component.

[0035] In this specification, the term "display device" may include display devices in a narrow sense, such as a liquid crystal module (LCM) including a display panel and a driver for driving the display panel, an organic light emitting module (OLED module), and a quantum dot module. It may also include set electronic apparatus or set device or set apparatus, such as a notebook computer, a television, a computer monitor, an automotive display apparatus or other forms of a vehicle, which are complete products or final products including the LCM, OLED module, and QD module, and a mobile electronic apparatus, such as a smartphone or an electronic pad.

[0036] Therefore, the display device in this specification can include a display device itself in the narrow sense, such as an LCM, an OLED module, a QD module, etc., as well as a set device that is an application product or a final consumer device that includes an LCM, an OLED module, a QD module, etc.

[0037] In some cases, an LCM, OLED module, or QD module consisting of a display panel and a driver may be expressed as a "display device" in the narrow sense, and an electronic device as a completed product including an LCM, OLED module, or QD module may be expressed as a "set device." For example, a display device in the narrow sense may include a liquid crystal (LCD), organic light emitting diode (OLED), or quantum dot display panel and a source PCB that is a controller for driving the display panel, and the set device may further include a set PCB that is a set controller electrically connected to the source PCB and controls the entire set device.

[0038] The display panel used in the embodiments of the present specification may be any type of display panel, such as a liquid crystal display panel, an organic light emitting diode (OLED) display panel, a quantum dot (QD) display panel, an electroluminescent display panel, etc. The display panel of the present embodiment is not limited to a specific display panel that can be bezel-bent using a flexible substrate for an organic light emitting diode (OLED) display panel and a lower back plate support structure. In addition, the display panel used in the display device according to the embodiments of the present specification is not limited to a specific type or size.

[0039] For example, when the display panel is an organic electroluminescence (OLED) display panel, it may include a number of gate lines and data lines, and pixels formed at the intersections of the gate lines and / or data lines. The display panel may include an array including thin film transistors, which are elements for selectively applying voltage to each pixel, a light emitting element layer on the array, and an encapsulation substrate or encapsulation layer disposed on the array to cover the light emitting element layer. The encapsulation layer may protect the thin film transistors and the light emitting element layer from external impacts and prevent moisture or oxygen from penetrating into the light emitting element layer. The layer formed on the array may include an inorganic light emitting layer, for example, a nano-sized material layer or quantum dots.

[0040] The features of the various embodiments of this specification may be partially or fully combined or combined with each other, may be technically interlocked and driven in various ways, and each embodiment may be implemented independently of each other or may be implemented together in a related relationship.

[0041] The following describes the embodiments of the present specification with reference to the accompanying drawings and examples. The scales of the components shown in the drawings are different from the actual scales for convenience of explanation, and are not limited to the scales shown in the drawings. In addition, all components of each flexible display device according to all the embodiments of the present specification may be configured to be operably coupled.

[0042] FIG. 1 is a block diagram of a flexible display device according to an embodiment of the present disclosure.

[0043] Referring to FIG. 1, a flexible display device 100 according to an embodiment of the present specification may include an image processor 151, a timing controller 152, a data driver 153, a gate driver 154, and a display panel 110.

[0044] At this time, the image processor 151 can output an externally supplied data signal DATA, a data enable signal DE, etc. In addition to the data enable signal DE, the image processor 151 can output at least one of a vertical sync signal, a horizontal sync signal, and a clock signal.

[0045] The timing controller 152 receives a data signal DATA together with a data enable signal DE or drive signals including a vertical sync signal, a horizontal sync signal, a clock signal, etc. from the image processor 151. The timing controller 152 can output a gate timing control signal GDC for controlling the operation timing of the gate driver 154 and a data timing control signal DDC for controlling the operation timing of the data driver 153 based on the drive signals.

[0046] In addition, the data driver 153 can sample and latch the data signal DATA supplied from the timing controller 152 in response to the data timing control signal DDC supplied from the timing controller 152, convert it into a gamma reference voltage, and output it. The data driver 153 can output the data signal DATA through the data lines DL1 to DLn.

[0047] Furthermore, the gate driver 154 can output gate signals while shifting the level of the gate voltage in response to a gate timing control signal GDC supplied from the timing controller 152. The gate driver 154 can output gate signals through the gate lines GL1 to GLm.

[0048] The display panel 110 can display an image by the sub-pixels P emitting light in response to the data signal DATA and the gate signal supplied from the data driver 153 and the gate driver 154. The detailed structure of the sub-pixels P will be described in detail with reference to Figures 2 and 7a. For example, each sub-pixel P in Figure 1 may have the configuration of the sub-pixels P in Figures 2 and 7a.

[0049] FIG. 2 is a circuit diagram of a sub-pixel of a flexible display device according to an embodiment of the present disclosure.

[0050] Referring to FIG. 2, a sub-pixel of a flexible display device according to an embodiment of the present disclosure may include a switching transistor ST, a driving transistor DT, a compensation circuit 135 and a light emitting element 130.

[0051] The light emitting element 130 is operable to emit light by a driving current generated by the driving transistor DT.

[0052] The switching transistor ST can perform a switching operation such that a data signal supplied through a data line 117 in response to a gate signal supplied through a gate line 116 is stored as a data voltage in the capacitor CST.

[0053] The driving transistor DT can operate so that a constant driving current flows between the high potential power line VDD and the low potential power line GND in response to the data voltage stored in the capacitor CST.

[0054] The compensation circuit 135 is a circuit for compensating for the threshold voltage of the driving transistor DT, and may include one or more thin film transistors and a capacitor. The configuration of the compensation circuit 135 may vary widely depending on the compensation method.

[0055] The sub-pixel shown in FIG. 2 is configured in a 2T (Transistor) 1C (Capacitor) structure including a switching transistor ST, a driving transistor DT, a capacitor Cst, and a light-emitting element 130, but when a compensation circuit 135 is added, it can be variously configured as 3T1C, 4T2C, 5T2C, 6T1C, 6T2C, 7T1C, 7T2C, etc.

[0056] FIG. 3 is a plan view of a flexible display device according to an embodiment of the present disclosure.

[0057] In particular, FIG. 3 illustrates an example in which the flexible substrate 111 of the flexible display device 100 according to an embodiment of the present disclosure is not bent.

[0058] 3, in the flexible display device 100 according to an embodiment of the present specification, the display panel 110 may include a display area AA in which pixels that actually emit light through thin film transistors and light emitting elements are arranged on a substrate 111, and a non-display area NA which is a bezel area surrounding the edge of the display area AA. That is, the non-display area NA may surround the entire edge of the display area AA.

[0059] The non-display area NA of the substrate 111 may be arranged with circuits such as a gate driver 154 for driving the display panel 110, and various signal wirings such as scan lines SL (used to scan the display panel from top to bottom), gate lines, vertical synchronization lines VSYN, horizontal synchronization lines HSYNC, data clocks DCLK, etc.

[0060] A circuit for driving the display panel 110 may be disposed on the substrate 111 in a GIP (Gate in Panel) manner, or may be connected to the substrate 111 in a TCP (Tape Carrier Package) or COF (Chip on Film) manner.

[0061] A plurality of pads 155 are arranged on one side of the substrate 111 in the non-display area NA, and an external module can be bonded thereto.

[0062] Meanwhile, a portion of the non-display area NA of the substrate 111 can be bent in the bending direction as shown by the arrow to form a bending area BA.

[0063] The non-display area NA of the substrate 111 is an area where wiring and driving circuits for driving a screen are arranged. The non-display area NA is not an area where an image is displayed, and therefore does not need to be viewed from the top surface of the substrate 111. That is, the non-display area NA does not include pixels that emit light, and therefore may be arranged in a curved shape that cannot be seen by a user. Therefore, a portion of the non-display area NA of the substrate 111 may be bent to reduce the bezel area while still securing an area for wiring and driving circuits.

[0064] For example, various wirings may be formed on the substrate 111. The wirings may be formed in the display area AA of the substrate 111, and the wirings 140 formed in the non-display area NA may connect driving circuits, gate drivers, data drivers, etc. to each other to transmit signals.

[0065] For example, the wiring 140 may be formed of a conductive material having excellent ductility to reduce the occurrence of cracks when bending the substrate 111. For example, the wiring 140 may be formed of a conductive material having excellent ductility such as gold (Au), silver (Ag), aluminum (Al), etc., or may be formed of one of various conductive materials used in the display area AA. The wiring 140 may also be made of molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), an alloy of silver (Ag) and magnesium (Mg), etc.

[0066] The wiring 140 may be configured in a multi-layer structure including various conductive materials, for example, a three-layer structure of titanium (Ti) / aluminum (Al) / titanium (Ti), but is not limited thereto.

[0067] The wiring 140 formed in the bending area BA is subjected to a tensile force when it is bent. For example, the wiring 140 extending in the same direction as the bending direction is subjected to the largest tensile force, which may cause cracks or breaks. Therefore, instead of arranging the wiring 140 to extend in the bending direction, at least a portion of the wiring 140 arranged including the bending area BA may be arranged to extend in a direction different from the bending direction, for example, in a diagonal direction, thereby minimizing the tensile force.

[0068] The wiring 140 arranged including the bending region BA may be formed in various shapes, such as a trapezoidal wave shape, a triangular wave shape, a sawtooth wave shape, a sine wave shape, an omega (Ω) shape, a diamond shape, and the like.

[0069] FIG. 4 is a perspective view of a flexible display device according to an embodiment of the present disclosure.

[0070] FIG. 5 is a perspective view illustrating a bending state of a flexible display device according to an embodiment of the present disclosure.

[0071] 4 and 5 show a case where one side, for example the bottom side, of the flexible display device is bent.

[0072] Referring to FIG. 4, the flexible display device of the embodiment herein may include a substrate 111 and a circuit element 161 .

[0073] The substrate 111 can be partitioned into a display area AA and a non-display area NA, which is a bezel area surrounding the edge of the display area AA.

[0074] The non-display area NA may further include a pad area PA located outside the bending area BA.

[0075] A plurality of sub-pixels may be arranged in the display area AA. The sub-pixels may be arranged in the display area AA in the form of R (red), G (green) and B (blue) or R, G, B and W (white) to realize full colors. The sub-pixels may be partitioned by gate lines and data lines intersecting each other.

[0076] The circuit element 161 may include bumps (or terminals). The bumps of the circuit element 161 may be in contact with the pads of the pad area PA through an anisotropic conductive film (ACF). The anisotropic conductive film is a type of adhesive that allows electrical conduction only in the thickness direction, and has good mechanical strength and high electrical conductivity.

[0077] The circuit element 161 may be a chip on film (COF) in which a driving integrated circuit (IC) is mounted on a flexible film. The circuit element 161 may also be implemented as a chip on glass (COG) type in which the circuit element 161 is directly bonded to a pad on the substrate 111 in a COG process. The COG process is a manufacturing process of a display device in which a display driver electronic device is integrated into a glass substrate of the display device. Therefore, a separate printed circuit board PCB is not required. The circuit element 161 may also be a flexible circuit such as a flexible flat cable (FFC) or a flexible printed circuit (FPC). However, in the following embodiments, the circuit element 161 will be described mainly in the form of a COF as an example, but the present specification is not limited thereto.

[0078] Driving signals, such as gate signals and data signals, supplied through the circuit elements 161 can be supplied to gate lines and data lines of the display area AA through wiring 140 such as routing lines.

[0079] In a flexible display device, in addition to a display area AA where an input image is realized, a sufficient space must be provided for locating a pad area PA and circuit elements 161, etc. The pad area PA, i.e., the space for locating the circuit elements 161, may correspond to a bezel area, which is recognized by a user as being located in front of the flexible display device and may somewhat reduce aesthetics. That is, the bezel area may potentially constitute the front of the flexible display device that is undesirable to the user.

[0080] Referring to FIG. 5, in the case of a flexible display device according to an embodiment of the present disclosure, the lower edge of the substrate 111 may be bent toward the rear side to have a predetermined curvature.

[0081] The lower edge of the substrate 111 may be outside the display area AA and may correspond to the area where the pad area PA is located. By bending the substrate 111, the pad area PA may be positioned so as to overlap the display area AA on the rear side of the display area AA. Therefore, the bezel area recognized on the front side of the flexible display device may be minimized. As a result, the bezel width may be reduced and the aesthetics may be improved.

[0082] For this purpose, the substrate 111 may be made of a flexible material. For example, the substrate 111 may be made of a plastic material such as PI (Polyimide). Also, the wiring 140 may be made of a flexible material. For example, the wiring 140 may be made of a material such as a metal nano wire, a metal mesh, or a carbon nanotube (CNT). However, the wiring 140 is not limited thereto.

[0083] In addition, the wiring 140 according to an embodiment of the present specification may be arranged in a multi-layer structure (or a double wiring structure) in the non-display area NA including the bending area BA. This allows for more room in the wiring arrangement, making it easier to design the wiring / electrode arrangement.

[0084] Meanwhile, in order to reduce the bezel area, an outer frame of a flexible display device is formed using a UV or heat curing resin instead of a conventional metal frame. However, when curing the resin using UV, the resin may get into the inside of the bent flexible display device and may not be cured. In addition, the bezel area has wiring 140 passing through it, and the wiring 140 may hinder the curing of the resin that has gotten into the flexible display device.

[0085] Therefore, according to one embodiment of the present specification, a reflective layer 150 is added to the bottom of the wiring 140 in the bezel area to reflect UV light and uniformly and completely harden the resin for the inner side sealing and outer side sealing in the bending area BA, thereby preventing assembly defects due to leakage of uncured resin, which will be described in detail with reference to the drawings.

[0086] FIG. 6a is a cross-sectional view taken along line II' in FIG.

[0087] FIG. 6b is a cross-sectional view taken along line II-II' in FIG.

[0088] FIG. 7 is a partial cross-sectional view of a flexible display device according to an embodiment of the present disclosure.

[0089] FIG. 8 is a side view of the flexible display device of FIG.

[0090] In FIG. 8, for the sake of convenience, the display panel 110, wiring 140, and reflective layer 150 are shown as being exposed, but in reality, the display panel 110, wiring 140, and reflective layer 150 may be covered by the microcoating layer 160 and the outer sealant 185 and may not be exposed.

[0091] FIG. 6a shows in detail the cross-sectional structure of the display area AA described in FIG. 3, and FIG. 6b shows in detail the cross-sectional structure of the non-display area NA between the display area AA and the bending area BA.

[0092] FIG. 7 illustrates a bottom cross section of a flexible display device according to an embodiment of the present disclosure being bent.

[0093] FIG. 8 is a right side view of the flexible display device of FIG.

[0094] Referring to FIG. 6a, a substrate 111 serves to support and protect components of a flexible display device disposed thereon.

[0095] Recently, flexible substrate 111 has been used as a ductile material with flexible properties such as plastic, that is, substrate 111 can have a certain elastic deformation to allow a certain degree of warping.

[0096] The substrate 111 may be in the form of a film including one selected from the group consisting of polyester-based polymers, silicone-based polymers, acrylic-based polymers, polyolefin-based polymers, and copolymers thereof.

[0097] The substrate 111 may include a first substrate 111a, a second substrate 111b, and an insulating layer 111c. The insulating layer 111c may be disposed between the first substrate 111a and the second substrate 111b. By configuring the substrate 111 with the first substrate 111a, the second substrate 111b, and the insulating layer 111c, moisture penetration may be prevented. For example, the first substrate 111a and the second substrate 111b may be polyimide (PI) substrates. The insulating layer 111c may be in the form of a film, and may provide soundproofing and vibration blocking functions, and may insulate the flexible display device (e.g., substrate 111) from external elements such as water and particulate matter.

[0098] A buffer layer may further be disposed on the substrate 111. The buffer layer can prevent external moisture and other impurities from penetrating through the substrate 111 and can flatten the surface of the substrate 111. The buffer layer is not necessarily a necessary configuration and may be omitted depending on the type of the thin film transistor 120 disposed on the substrate 111.

[0099] A thin film transistor 120 may be disposed on top of the substrate 111 .

[0100] For example, the thin film transistor 120 may include a gate electrode 121 , a semiconductor layer 124 , a source electrode 122 and a drain electrode 123 .

[0101] For example, the semiconductor layer 124 may be made of, but is not limited to, amorphous silicon or polycrystalline silicon. Polycrystalline silicon has better mobility than amorphous silicon, has lower energy consumption, and is more reliable, and can be applied to driving thin film transistors in pixels.

[0102] Furthermore, for example, the semiconductor layer 124 can be made of an oxide semiconductor. An oxide semiconductor has excellent properties in terms of mobility and uniformity.

[0103] The oxide thin film transistor 120, which has a semiconductor layer 124 made of an oxide semiconductor, can be driven in a GIP mode at 1-10 Hz based on its excellent off-current characteristics compared to existing LTPS (Low Temperature Polycrystalline Silicon) thin film transistors, thereby enabling low-power driving.

[0104] The semiconductor layer 124 may include source and drain regions containing p-type or n-type impurities and a channel region between the source and drain regions, and may further include a lightly doped region between the channel region and the adjacent source and drain regions.

[0105] The source region and the drain region are regions doped with impurities at a high concentration, and a source electrode 122 and a drain electrode 123 of the thin film transistor 120 may be connected thereto, respectively.

[0106] The impurity ions can be p-type or n-type impurities, where the p-type impurity can be one of boron (B), aluminum (Al), gallium (Ga), and indium (In), and the n-type impurity can be one of phosphorus (P), arsenic (As), and antimony (Sb).

[0107] In addition, the channel region of the semiconductor layer 124 may be doped with n-type impurities or p-type impurities depending on the structure of the NMOS or PMOS thin film transistor, and the thin film transistor included in the flexible display device according to one embodiment of the present specification may be an NMOS or PMOS thin film transistor.

[0108] A first insulating layer 115a may be disposed on the semiconductor layer 124.

[0109] The first insulating layer 115a may be composed of a single layer of silicon oxide (SiOx) or silicon nitride (SiNx) or multiple layers thereof, and may be arranged so that a current flowing through the semiconductor layer 124 does not flow through the gate electrode 121. Silicon oxide is less ductile than metal but is more ductile than silicon nitride, and may be composed of a single layer or multiple layers depending on its characteristics.

[0110] A gate electrode 121 may be disposed on the first insulating layer 115a.

[0111] The gate electrode 121 acts as a switch that turns on or off the thin film transistor 120 based on an electrical signal transmitted from the outside through a gate line, and may be formed of a single layer or multiple layers of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), etc., or alloys thereof, but is not limited thereto.

[0112] A second insulating layer 115b may be disposed on the gate electrode 121.

[0113] For example, the second insulating layer 115b serves to insulate the gate electrode 121 from the source electrode 122 and the drain electrode 123, and may be composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx).

[0114] A source electrode 122 and a drain electrode 123 may be disposed on the second insulating layer 115b.

[0115] The source electrode 122 and the drain electrode 123 are connected to a data line so that an electrical signal transmitted from the outside can be transmitted from the thin film transistor 120 to the light emitting element 130. For example, the source electrode 122 and the drain electrode 123 may be formed as a single layer or multiple layers using conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), etc., or alloys thereof, but are not limited thereto.

[0116] A protective layer made of an inorganic insulating layer such as silicon oxide (SiOx) or silicon nitride (SiNx) may be further disposed on the thin film transistor 120 configured as above.

[0117] The protective layer can prevent unnecessary electrical connections between components disposed above and below the protective layer and can prevent contamination or damage from the outside, and may be omitted depending on the configuration and characteristics of the thin film transistor 120 and the light emitting device 130.

[0118] The thin film transistor 120 may be classified into an inverted staggered structure and a coplanar structure depending on the positions of the components constituting the thin film transistor 120. For example, in a thin film transistor having an inverted staggered structure, the gate electrode may be located on the opposite side of the source electrode and the drain electrode with respect to the semiconductor layer. For example, the inverted staggered structure is a type of TFT in which the gate electrode is located at the bottom of the device (e.g., a flexible display device), and the source electrode and the drain electrode may be located at the top of the device. In contrast, as shown in FIG. 6a, in a thin film transistor 120 having a coplanar structure, the gate electrode 121 may be located on the same side as the source electrode 122 and the drain electrode 123 with respect to the semiconductor layer 124.

[0119] In FIG. 6a, a thin film transistor 120 having a coplanar structure is shown, but is not limited thereto, and a flexible display device according to an embodiment of the present specification may include a thin film transistor having an inverted staggered structure.

[0120] For ease of explanation, only the driving thin film transistor 120 is shown among various thin film transistors that may be included in the flexible display device, but a switching thin film transistor, a capacitor, etc. may also be included in the flexible display device. When a signal is applied from a gate line, the switching thin film transistor can transmit a signal of a data line to a gate electrode 121 of the driving thin film transistor 120. In addition, the driving thin film transistor 120 can transmit a current transmitted through a power supply line to the anode 131 according to the signal transmitted from the switching thin film transistor, and can control light emission according to the current transmitted to the anode 131.

[0121] Planarization layers 115c and 115d may be disposed on the thin film transistor 120. The planarization layers 115c and 115d may be disposed to protect the thin film transistor 120, reduce a step caused by the thin film transistor 120, and reduce a parasitic capacitance generated between the thin film transistor 120 and the gate line, the data line, and the light emitting element 130.

[0122] For example, the planarization layers 115c and 115d may be formed of one or more materials including, but not limited to, acrylic resin, epoxy resin, phenolic resin, polyamides resin, polyimides resin, unsaturated polyesters resin, polyphenylene resin, polyphenylene sulfides resin, and benzo cyclobutene.

[0123] 6a, the planarization layers 115c and 115d may have a multi-layer structure composed of at least two layers, and may include, but are not limited to, a first planarization layer 115c and a second planarization layer 115d. The first planarization layer 115c may be disposed to cover the thin film transistor 120 and may expose a portion of the source electrode 122 and the drain electrode 123 of the thin film transistor 120.

[0124] The planarization layers 115c, 115d may be, but are not limited to, an overcoat layer.

[0125] In addition, an intermediate electrode 125 for electrically connecting the thin film transistor 120 and the light emitting element 130 may be disposed on the first planarization layer 115c. Although not shown in Fig. 6a, various metal layers serving as wiring / electrodes such as data lines and signal wiring may be disposed on the first planarization layer 115c.

[0126] In addition, a second planarization layer 115d may be disposed on the first planarization layer 115c and the intermediate electrode 125.

[0127] For example, in the first embodiment of the present specification, the planarization layers 115c and 115d are formed of two layers because various signal wirings have increased as the resolution of the display panel has increased. Since it is difficult to arrange all the wirings in one layer while ensuring the minimum spacing, an additional layer is provided. The addition of such an additional layer, for example, the second planarization layer 115d, provides more space for wiring arrangement, and may facilitate the design of wiring and electrode arrangement. In addition, when a dielectric material is used as the planarization layers 115c and 115d configured in multiple layers, the planarization layers 115c and 115d may be used to form capacitance between metal layers.

[0128] The second planarization layer 115d may be formed to expose a portion of the intermediate electrode 125, and the drain electrode 123 of the thin film transistor 120 and the anode 131 of the light emitting element 130 may be electrically connected through the intermediate electrode 125.

[0129] The light emitting element 130 may be disposed on the second planarization layer 115d.

[0130] The light emitting element 130 may include an anode 131 , a light emitting portion 132 , and a cathode 133 .

[0131] An anode 131 may be disposed on the second planarization layer 115d.

[0132] The anode 131 is an electrode that serves to supply holes to the light emitting portion 132, and is connected to the intermediate electrode 125 through a contact hole formed in the second planarization layer 115d, and can be electrically connected to the thin film transistor 120 therethrough.

[0133] The anode 131 may be made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), but is not limited thereto.

[0134] In the case where the flexible display device is a top emission type that emits light from above where the cathode 133 is disposed, a reflective layer may be further included so that the emitted light can be reflected by the anode 131 and more smoothly emitted toward the upper side where the cathode 133 is disposed. For example, the anode 131 may have a two-layer structure in which a transparent conductive layer and a reflective layer made of a transparent conductive material are laminated in order, or a three-layer structure in which a transparent conductive layer, a reflective layer, and a transparent conductive layer are laminated in order, and the reflective layer may be made of silver (Ag) or an alloy containing silver (Ag). However, the present invention is not limited thereto, and may also be applied to a bottom emission type.

[0135] A bank 115e may be disposed on the anode 131 and the second planarization layer 115d.

[0136] The bank 115e may define a subpixel by dividing an area that actually emits light. For example, the bank 115e may be formed by forming a photoresist on the anode 131 and then performing a photolithography process.

[0137] Photoresist refers to a photosensitive resin whose solubility in a developer changes due to the action of light, and a specific pattern can be obtained by exposing and developing the photoresist. Photoresist can be classified into positive photoresist and negative photoresist. Positive photoresist refers to a photoresist whose solubility in a developer of an exposed portion increases upon exposure, and a pattern in which the exposed portion is removed can be obtained by developing the positive photoresist. Negative photoresist refers to a photoresist whose solubility in a developer of an exposed portion decreases significantly upon exposure, and a pattern in which the unexposed portion is removed can be obtained by developing the negative photoresist.

[0138] In order to form the light emitting portion 132 of the light emitting element 130, a fine metal mask (FMM) which is a deposition mask can be used.

[0139] For example, in order to prevent damage that may occur due to contact with a deposition mask placed on the bank 115e and to maintain a certain distance between the bank 115e and the deposition mask, a spacer 115f made of one of polyimide, photoacrylic, and benzocyclobutene (BCB) may be placed on the top of the bank 115e.

[0140] The light emitting portion 132 may be disposed between the anode 131 and the cathode 133 .

[0141] The light emitting unit 132 emits light and may include at least one layer selected from the group consisting of a hole injection layer (HIL), a hole transport layer (HTL), an emissive layer (EML), an electron transport layer (ETL) and an electron injection layer (EIL), and some components may be omitted depending on the structure and characteristics of the flexible display device. Here, the light emitting layer may be an electroluminescent layer or an inorganic light emitting layer.

[0142] The hole injection layer is disposed on the anode 131 and serves to facilitate the injection of holes.

[0143] The hole transport layer is disposed on the hole injection layer and serves to smoothly transport holes to the light emitting layer.

[0144] The light-emitting layer is disposed on the hole-transporting layer and can emit light of a specific color by including a material capable of emitting light of a specific color, and the light-emitting material can be formed using a phosphorescent material or a fluorescent material.

[0145] An electron injection layer may be further disposed on the electron transport layer. The electron injection layer is an organic layer that facilitates the injection of electrons from the cathode 133, and may be omitted depending on the structure and characteristics of the flexible display device.

[0146] Meanwhile, an electron blocking layer (EBL) or hole blocking layer (HBL) for blocking the flow of holes or electrons can be further disposed adjacent to the light emitting layer to prevent the phenomenon that electrons, when injected into the light emitting layer, move from the light emitting layer to pass through the adjacent hole transport layer, or holes, when injected into the light emitting layer, move from the light emitting layer to pass through the adjacent electron transport layer, thereby improving light emitting efficiency. An electron blocking layer (EBL) is a semiconductor material layer used to prevent electrons from flowing from one region of the device to another. An electron blocking layer (EBL) can prevent electrons from flowing from the active region to the p-type layer. A hole blocking layer (HBL) is a semiconductor material layer used to prevent holes from flowing from one region of the device to another.

[0147] The cathode 133 is disposed on the light emitting portion 132 and serves to supply electrons to the light emitting portion 132. Since the cathode 133 must supply electrons, it may be made of a metal material having a low work function, such as magnesium (Mg), silver-magnesium, etc., but is not limited thereto.

[0148] When the flexible display device is a top emission type, the cathode 133 may be a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide (ZnO) and tin oxide (TO) series.

[0149] For example, an encapsulation portion 115g may be disposed on the top of the light-emitting element 130 to prevent the thin film transistor 120 and the light-emitting element 130, which are components of the flexible display device, from being oxidized or damaged due to moisture, oxygen or impurities flowing in from the outside, and may be formed by stacking a plurality of encapsulation layers, foreign matter compensation layers and a plurality of barrier films.

[0150] The encapsulation layer may be disposed on the upper front surface of the thin film transistor 120 and the light emitting device 130, and may be made of one of inorganic materials such as silicon nitride (SiNx) or aluminum oxide (AlyOz), but is not limited thereto.

[0151] The foreign matter compensation layer is disposed on the encapsulation layer and may be made of, but is not limited to, organic silicon oxycarbonate (SiOCz), acryl, or epoxy resin. When defects occur due to cracks caused by foreign matter or particles that may occur during processing, the foreign matter compensation layer can cover and compensate for the bends and foreign matter.

[0152] A barrier film is disposed on the encapsulation layer and the foreign matter compensation layer to retard the penetration of oxygen and moisture from the outside into the flexible display device. The barrier film is configured in the form of a film having translucency and double-sided adhesiveness, and may be made of any one of insulating materials of olefin series, acrylic series, and silicon series, or may further be laminated with a barrier film made of any one of materials such as COP (Cycloolefin Polymer), COC (Cycloolefin Copolymer), and PC (Polycarbonate), but is not limited thereto.

[0153] Although not shown, for example, a polarizing film may be disposed on top of sealing portion 115g.

[0154] In addition, a touch panel may be disposed on the polarizing film, but the present specification is not limited thereto, and the polarizing film may be disposed on the touch panel.

[0155] A touch panel is an input method that allows a user to directly input information onto a screen by pressing the display screen with their hand or a pen. For example, a touch panel allows a user to directly perform a desired task while looking at the screen, and since it is easy for anyone to operate, it is considered the most ideal input method in a GUI (Graphical User Interface) environment, and is currently widely used in various fields such as mobile phones, PDAs, banks and government offices, various medical equipment, and tourist and major organization guides.

[0156] Next, the cross-sectional structure of the non-display area will be described with reference to FIG. 6b.

[0157] As mentioned above, FIG. 6b details the cross-sectional structure of the non-display area between the display area and the bending area.

[0158] Some components in FIG. 6b are substantially the same as or similar to those described in FIG. 6a, and the description thereof will be omitted.

[0159] The gate signals and data signals described in Figures 1 to 3 can be transmitted from the outside to pixels arranged in the display area via wiring 140 arranged in the non-display area of ​​the flexible display device, thereby causing them to emit light.

[0160] For example, the wiring 140 may be formed of a conductive material having excellent ductility in order to reduce the occurrence of cracks when the substrate 111 is bent.

[0161] For example, the wiring 140 may be formed of a conductive material having excellent ductility, such as gold (Au), silver (Ag), aluminum (Al), etc. For example, the wiring 140 may be formed of one of various conductive materials used in the display region, and may be composed of an alloy of molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), silver (Ag), magnesium (Mg), etc. For example, the wiring 140 may be configured in a multi-layer structure including various conductive materials, and may be configured in a three-layer structure of titanium (Ti) / aluminum (Al) / titanium (Ti), but is not limited thereto.

[0162] In addition, in order to protect the wiring 140, a buffer layer made of an inorganic insulating layer may be disposed under the wiring 140, and a protective layer made of an inorganic insulating layer may be formed to surround the upper and sides of the wiring 140, thereby preventing the wiring 140 from reacting with moisture, etc., and being corroded.

[0163] The wiring 140 formed in the bending region receives a tensile force when bending. As described in FIG. 3, the wiring 140 extending in the same direction as the bending direction on the substrate 111 receives the largest tensile force, and cracks may occur, and if the cracks are severe, disconnection may occur. Therefore, instead of forming the wiring 140 to extend in the bending direction, at least a portion of the wiring 140 arranged including the bending region is formed to extend in a direction different from the bending direction, for example, in a diagonal direction, thereby minimizing the tensile force and reducing the occurrence of cracks. That is, by arranging the wiring 140 in a diagonal direction, when the wiring 140 is bent, it is not exposed to much tensile stress, and the occurrence of cracks can be reduced. In addition, the shape of the wiring 140 may be configured to be a rhombus shape, a triangular wave shape, a sine wave shape, a trapezoid shape, etc., but is not limited thereto.

[0164] A first planarization layer 115c may be disposed on top of the substrate 111.

[0165] Then, the wiring 140 can be disposed on the first planarization layer 115c.

[0166] In addition, a second planarization layer 115d may be disposed on the wiring 140. For example, the first planarization layer 115c and the second planarization layer 115d may be formed of one or more materials selected from the group consisting of acrylic resin, epoxy resin, phenolic resin, polyamides resin, polyimides resin, unsaturated polyesters resin, polyphenylene resin, polyphenylene sulfides resin, and benzo cyclobutene, but are not limited thereto.

[0167] On top of the second planarization layer 115d, banks 115e and / or a micro-coating layer (MLC) 160 may be disposed.

[0168] The micro-coating layer 160 is formed by coating a thin resin layer at the bending location to prevent cracks that may occur due to tensile force acting on the wiring 140 placed on the top of the substrate 111 during bending, and serves to protect the wiring 140.

[0169] Meanwhile, as display devices are becoming smaller, efforts are being made to reduce a bezel area, which is an outer periphery of a display area, in order to increase the size of an effective display screen within the same area of ​​the display device.

[0170] Also, in order to reduce the bezel area, an outer frame of a flexible display device is formed using a UV or heat curing resin instead of a conventional metal frame. However, when the resin is cured using UV, the resin may enter the inside of the bent flexible display device and not be cured. For example, the resin that entered the inside of the bent flexible display device during UV curing may not be cured and may leak out of the bending area, or the difference in curing of the resin inside and outside the bending area may cause a difference in bending stress, which may cause delamination of components such as an adhesive layer. That is, the curing time of the resin outside the bending area may differ from that inside the bending area due to, for example, air flow, temperature difference, etc. Also, wiring may pass through the bezel area, and the curing of the resin that entered the inside of the flexible display device may be hindered by the wiring. To prevent this problem, an additional process may be performed to seal the gaps on both sides of the bending area before UV curing, but the additional process may complicate the entire process, and the resin may still not be cured and the adhesive layer may still peel off.

[0171] Therefore, in one embodiment of the present specification, for example, a reflective layer 150 may be disposed under the wiring 140 in the non-display area between the display area and the bending area.

[0172] For example, but not limited to, the reflective layer 150 may be disposed in an entire electrode configuration across the non-display area adjacent to the bending area (see FIGS. 4-5). For example, when the flexible display device is viewed from above, the reflective layer 150 may be disposed between and along the traces 140 in an island configuration (e.g., a single "island" or strip of material).

[0173] For example, the reflective layer 150 may reflect UV light incident from the side and / or the bottom of the flexible display device, i.e., the bottom of the flexible display device where the bent substrate 111 is located, to uniformly and completely harden the inner sealant 180 and the outer sealant 185 in the bending region. The reflective layer 150 may be formed in a single layer or a multi-layer structure made of any one of opaque metals such as aluminum (Al), nickel (Ni), chromium (Cr), tungsten (W), titanium (Ti), neodymium (Nd), molybdenum (Mo), and copper (Cu), or an alloy thereof, and the embodiments of the present specification are not limited thereto.

[0174] For example, the reflective layer 150 can reflect UV light that has passed through the microcoating layer 160, the bank 115e, the first planarization layer 115c, and the second planarization layer 115d in the bending region and the non-display region around the bending region, thereby further hardening the inner sealant 180 inside the bending region. Thus, (for example, by forming the inner sealant 180 or the outer sealant 185) it is possible to prevent assembly defects caused by leakage of uncured resin, and it is possible to prevent assembly defects caused by a difference in hardening of the inner sealant 180 and the outer sealant 185 without an additional process.

[0175] For example, the reflective layer 150 is disposed on a flat portion of the non-display area between the display area and the bending area, so that UV light entering from the side of the bending area does not get in the bending area.

[0176] When UV light is incident from the lower part of the flexible display device, for example, the lower part of the bent substrate 111 where the pad region is located, the reflective layer 150 may be disposed in a direction opposite to the direction in which the UV light is incident. For example, the reflective layer 150 may be disposed on the upper part of the substrate 111 in the non-display region between the display region and the bent region, facing the bent substrate 111 so as not to obstruct the incidence of the UV light.

[0177] In this case, for example, the reflective layer 150 may be disposed under the wiring 140 on the substrate 111 in the non-display area between the display area and the bending area so as not to interfere with the incidence of UV light by the wiring 140. For example, the reflective layer 150 may be disposed between the substrate 111 and the first planarization layer 115c, but is not limited thereto.

[0178] 7 and 8, a barrier film 173 may be disposed on top of the display panel 110. As shown in FIG.

[0179] The barrier film 173 is configured to protect various components of the flexible display device, and may be disposed to correspond to at least the display area AA of the flexible display device.

[0180] For example, the barrier film 173 may be made of a material having adhesive properties, such as a pressure sensitive adhesive (PSA), and may serve to fix the polarizing plate 171 on the barrier film 173.

[0181] The barrier film 173 can be positioned to protect an area much larger than the display area AA.

[0182] The polarizing plate 171 disposed on the barrier film 173 can suppress reflection of external light above the display area AA. When the flexible display device is used outdoors, external natural light enters and may be reflected by a reflective layer included in the anode of the light emitting device, or by an electrode made of opaque metal disposed below the light emitting device. Such reflected light may make it difficult to view images on the flexible display device. The polarizing plate 171 polarizes the light entering from the outside in a specific direction and prevents the reflected light from being emitted outside the flexible display device.

[0183] The polarizing plate 171 may be disposed above the display area AA, but is not limited to this.

[0184] The polarizing plate 171 may be a polarizing plate formed of a polarizer and a protective film for protecting the polarizing plate, or may be formed by coating a polarizing material for flexibility.

[0185] A cover glass 175 for protecting the appearance of the flexible display device may be disposed on the polarizing plate 171 with an adhesive layer 177 interposed therebetween.

[0186] A light blocking layer 176 may be disposed on the bottom edge of the cover glass 175 .

[0187] A backplate 101 may be disposed below the display panel 110 .

[0188] In the case where the substrate of the display panel 110 is made of a plastic material such as polyimide, the manufacturing process of the flexible display device is carried out in a state where a supporting substrate made of glass is disposed under the display panel 110, and after the manufacturing process is completed, the supporting substrate can be separated and released.

[0189] Since components are required to support the display panel 110 even after the support substrate is released, a backplate 101 may be disposed under the display panel 110 to support the display panel 110 .

[0190] For example, the backplate 101 may be disposed adjacent to the bending area BA in other areas of the display panel 110 except the bending area BA.

[0191] For example, the backplate 101 may be made of a thin plastic film formed from polyimide, polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polymers, combinations of these polymers, and the like.

[0192] For example, the display panel 110 may include a first planar portion, a second planar portion, and a curved portion located between the first planar portion and the second planar portion.

[0193] The first plane portion corresponds to a display area AA having a plurality of sub-pixels and a part of a non-display area NA and is an area that maintains a flat state, and the second plane portion faces the first plane portion, corresponds to a pad portion having pads to be bonded to circuit elements, and is an area that maintains a flat state.

[0194] Moreover, the curved surface portion may correspond to a bending area BA that maintains a state in which it is bent at a predetermined curvature.

[0195] In this case, for example, the bending area BA may have a "⊃" shape. For example, the curved portion may extend from the first flat portion and be bent 180 degrees toward the rear surface, but the curved portion may be bent at an angle other than 0 degrees and 360 degrees. As a result, the second flat portion extending from the curved portion may be positioned so as to overlap the first flat portion on the rear surface of the first flat portion. Thus, the circuit element bonded to the display panel 110 at the second flat portion may be positioned toward the rear surface of the display panel 110 of the first flat portion. However, the present invention is not limited thereto.

[0196] For example, the backplate 101 may be composed of a first backplate 101a and a second backplate 101b located on the back surface of the first and second planar portions, respectively. The first backplate 101a reinforces the rigidity of the first planar portion so that the first planar portion can be maintained in a flat state. The second backplate 101b reinforces the rigidity of the second planar portion so that the second planar portion can be maintained in a flat state. Meanwhile, in order to ensure the flexibility of the curved portion and to facilitate the control of the neutral plane using the microcoating layer 160, it is preferable that the backplate 101 is not located on the back surface of a portion of the curved portion.

[0197] The first back plate 101a may be attached to a first plane portion of the display panel 110 by a first adhesive layer 172a, and the second back plate 101b may be attached to a second plane portion of the display panel 110 by a second adhesive layer 172b, but is not limited thereto.

[0198] For example, the support member 105 may be disposed between the first backplate 101a and the second backplate 101b, and the support member 105 may be attached to the first backplate 101a and the second backplate 101b by the third adhesive layer 172c and the fourth adhesive layer 172d, respectively. For example, the support member 105 may be formed of a plastic material such as polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polymers, combinations of these polymers, etc. The strength of the support member 105 formed of such a plastic material may be controlled by adding an additive to increase the thickness and strength of the support member 105. And, the support member 105 may be formed of glass, ceramic, metal, or other rigid material, or a combination of the aforementioned materials.

[0199] For example, an additional barrier film 178 may be disposed between the support member 105 and the second back plate 101b, and the additional barrier film 178 may be configured to include an adhesive material and may be attached to the support member 105 by a fifth adhesive layer 172e. The additional barrier film 178 may act as a buffer or cushion. However, the present specification is not limited thereto, and the additional barrier film 178 may not be disposed.

[0200] A microcoating layer 160 may be disposed on an upper portion of the bending area BA of the display panel 110. The microcoating layer 160 may be disposed to cover one side of the barrier film 173.

[0201] Since microcracks may occur due to tension acting on the wires 140 disposed on the display panel 110 during bending, the microcoating layer 160 can function to protect the wires 140 by coating a thin resin on the bent positions. That is, the microcoating layer 160 is made of resin and applied on the wires 140 to reinforce cracks in the wires 140.

[0202] The microcoating layer 160 can adjust the neutral plane of the bending region BA. For example, the neutral plane means an imaginary plane where the compressive force and tensile force applied to the structure cancel each other out when the structure is bent and no stress is applied. When two or more structures are stacked, an imaginary neutral plane may be formed between the structures. When the entire structure is bent in one direction, the structures arranged in the bending direction based on the neutral plane are compressed by bending and therefore receive compressive force. Conversely, the structures arranged in the opposite direction to the bending direction based on the neutral plane are stretched by bending and therefore receive tensile force. In general, a structure is more fragile when it receives tensile force out of the same compressive and tensile forces, and therefore the probability of cracks occurring when it receives tensile force is higher. The substrate disposed below the neutral plane is compressed and receives a compressive force, while the wiring 140 disposed above the neutral plane may receive a tensile force, which may cause cracks. Therefore, the wiring 140 may be positioned on the neutral plane to minimize the tensile force it receives.

[0203] By placing the microcoating layer 160 on the top of the bending area BA, the neutral plane can be raised upward, and the neutral plane can be formed at the same position as the wiring 140 or positioned higher than the neutral plane, so that it is not subjected to stress or compression force during bending, thereby suppressing the occurrence of cracks.

[0204] If the thickness of the microcoating layer 160 is too thick, the overall thickness of the flexible display device increases, which hinders the thinning of the flexible display device, and if the thickness is too thin, the neutral surface is not optimized and it may be difficult to realize sufficient adhesive strength, so the thickness may be 70 μm to 130 μm.

[0205] The microcoating layer 160 may be made of a resin, and may be made of an acrylic material or a urethane acrylate, but is not limited thereto.

[0206] As described above, driving signals, such as gate signals and data signals, supplied through the circuit elements can be supplied to the gate lines and data lines of the display area AA through the wiring 140 such as routing lines.

[0207] For example, the wiring 140 may include, but is not limited to, a plurality of first wirings 141 that transmit data signals to the data lines and a plurality of second wirings 142 that are signal wirings for transmitting gate signals to the GIP circuit.

[0208] In the non-display area NA including the bending area BA, for example, the first wirings 141 may be arranged in the center and the second wirings 142 may be arranged on the edge, but is not limited thereto. For example, the second wirings 142 may be arranged laterally outward from the first wirings 141.

[0209] For example, a reflective layer 150 may be disposed under the wiring 140 in the non-display area NA between the display area AA and the bending area BA.

[0210] The reflective layer 150 may be disposed in the form of a whole electrode over the entire wiring 140 disposed in the non-display area NA between the display area AA and the bending area BA. For example, the reflective layer 150 may be disposed over the entire first wiring 141 and the second wiring 142, but is not limited thereto. For example, when the flexible display device is viewed from above, the reflective layer 150 may be disposed in an island form between the wiring 140 along the length of the wiring 140. That is, the reflective layer 150 may be disposed in a series of islands between each wiring 140. That is, the reflective layer 150 may be disposed over the entire wiring 140 (the first wiring 141 and the second wiring 142) as the wiring 140 extends between the non-display area NA and the display area AA, but may cover only a portion of the length of the wiring 140.

[0211] For example, the reflective layer 150 may be disposed on a first planar portion of the display panel 110 between the display area AA and the bending area BA.

[0212] For example, the reflective layer 150 may be disposed below the wiring 140 in the first planar portion of the display panel 110 between the display area AA and the bending area BA.

[0213] For example, the reflective layer 150 may be disposed on the first planar portion of the display panel 110 between the substrate 111 and the first planarization layer 115c, but is not limited thereto.

[0214] Meanwhile, in one embodiment of the present disclosure, an outer sealant 185 may be disposed on the edge of the flexible display device as an outer frame.

[0215] For example, the outer sealant 185 may be made of, but is not limited to, an epoxy mold. For example, the outer sealant 185 may be made of, but is not limited to, a UV-curable material, such as epoxy acrylate, urethane acrylate, polyester acrylate, urethane, urethane acrylate, silicone acrylate, etc., to which a UV-curable oligomer is added.

[0216] For example, the outer sealant 185 may be disposed in a frame shape along the four edges of the flexible display device, that is, the outer sealant 185 may surround the entire edge of the flexible display device.

[0217] For example, an outer sealant 185 may be disposed on the bottom edge of the cover glass 175 to cover the bent display panel 110 and the exposed adhesive layer 177 and microcoating layer 160 .

[0218] In addition, the inner space of the bent display panel 110 may be filled with an inner sealant 180 .

[0219] For example, the inner sealant 180 may be made of, but is not limited to, an epoxy mold. For example, the inner sealant 180 may be made of, but is not limited to, a UV-curable material, such as epoxy acrylate, urethane acrylate, polyester acrylate, urethane, urethane acrylate, silicone acrylate, etc., to which a UV-curable oligomer is added.

[0220] For example, the inner sealant 180 may be disposed on one side edge of the flexible display device to which the display panel 110 is bent.

[0221] The inner sealant 180 can be fully cured during UV curing by the reflective layer 150 .

[0222] Meanwhile, as mentioned above, when the flexible display device is viewed from a planar view, the reflective layer according to the embodiments of the present specification may be arranged between and along the wiring in an island form, which will be described in detail with reference to the drawings.

[0223] FIG. 9 is a diagram illustrating a part of a cross section of a flexible display device according to another embodiment of the present specification.

[0224] The flexible display device of another embodiment of the present specification in Figure 9 differs from the flexible display device of another embodiment of the present specification in Figures 3 to 8 described above only in the configuration of the reflective layer 250, and the other configurations are essentially the same, so duplicated descriptions will be omitted.

[0225] As with FIG. 6b above, FIG. 9 shows in detail the cross-sectional structure of the non-display area between the display area and the bending area.

[0226] Referring to FIG. 9, gate signals and data signals can be transmitted from the outside to pixels arranged in the display area via wiring 140 arranged in the non-display area of ​​the flexible display device to cause the pixels to emit light.

[0227] A first planarization layer 115c may be disposed on top of the substrate 111.

[0228] Then, the wiring 140 can be disposed on the first planarization layer 115c.

[0229] In addition, a second planarization layer 115d may be disposed on the wiring 140.

[0230] On top of the second planarization layer 115d, banks 115e and / or a microcoating layer 160 may be disposed.

[0231] In another embodiment of the present disclosure, for example, a reflective layer 250 may be disposed under the wiring 140 in the non-display area between the display area and the bending area.

[0232] In another embodiment of the present specification, for example, the reflective layer 250 may be disposed between the wirings 140 in an island shape along the wirings 140. For example, the reflective layer 250 may be disposed so as not to overlap with the wirings 140 in order to avoid generating parasitic capacitance, but is not limited thereto.

[0233] For example, the reflective layer 250 may be disposed on a flat portion of the non-display area between the viewing area and the bending area.

[0234] For example, the reflective layer 250 may be disposed under the wiring 140 on the substrate 111 in the non-display area between the display area and the bending area. For example, the reflective layer 250 may be disposed between the substrate 111 and the first planarization layer 115c, but is not limited thereto.

[0235] For example, the reflective layer 250 may be disposed in front of the bending area in a non-display area between the display area and the bending area, but is not limited thereto.

[0236] Hereinafter, a method for manufacturing the flexible display device 100 according to another embodiment of the present specification will be further described.

[0237] As shown in Fig. 3, the flexible display device 100 may include a display panel 110. The display panel 110 may include a display area AA and a non-display area NA. The non-display area NA may include a bending area BA. The bending area BA may be formed by bending a part of the non-display area NA in a bending direction. A plurality of light emitting elements 130 may be arranged in the display area AA of the display panel 110.

[0238] A manufacturing method of a flexible display device 100 according to one embodiment of the present specification may include a step of forming a plurality of wirings 140 extending to a display area AA in a non-display area NA of a display panel 110, and a step of forming a reflective layer (such as, for example, the reflective layer 150 shown in Figures 4-5 or the reflective layer 250 shown in Figure 9) under the plurality of wirings 140 in the non-display area NA between the display area AA and the bending area BA.

[0239] A flexible display device according to an embodiment of the present specification can be described as follows.

[0240] A flexible display device according to an embodiment of the present specification includes a display area and a non-display area, and the non-display area may include a display panel including a bending area, a plurality of light-emitting elements arranged on the display panel of the display area, a plurality of wirings arranged on the display panel of the non-display area and extending into the display area, and a reflective layer arranged under the wirings in the non-display area between the display area and the bending area.

[0241] According to some embodiments of the present disclosure, the flexible display device may further include a planarization layer disposed on top of the wiring, and a microcoating layer disposed on top of the planarization layer in the bending region.

[0242] According to some embodiments herein, the reflective layer may be disposed over the plurality of traces.

[0243] According to some embodiments of the present disclosure, the reflective layer may be formed in the form of a full electrode.

[0244] According to some embodiments of the present disclosure, when the flexible display device is viewed from above in a plan view, the reflective layer may be disposed over the entire non-display area.

[0245] According to some embodiments herein, the reflective layer may be formed in an island form.

[0246] According to some embodiments of the present disclosure, the display panel may include a first planar portion, a second planar portion, and a curved portion between the first planar portion and the second planar portion.

[0247] According to some embodiments of the present specification, the first planar portion corresponds to a first region of the display region and the non-display region and is maintained in a flat state, the second planar portion corresponds to a second region different from the first region of the non-display region and faces the first planar portion, and the curved portion corresponds to the bending region and is capable of maintaining a bent state with a predetermined curvature.

[0248] According to some embodiments herein, the reflective layer may be disposed on a first planar portion of the display panel between the display area and the bending area.

[0249] According to some embodiments of the present disclosure, the flexible display device may further include a cover glass disposed on the display panel.

[0250] According to some embodiments of the present disclosure, the flexible display device may further include an outer sealant disposed on a lower edge of the cover glass and arranged to cover an outer surface of the bending region.

[0251] According to some embodiments of the present disclosure, the flexible display device may further include a light-shielding layer disposed on a lower edge of the cover glass.

[0252] According to some embodiments herein, the outer sealant may be disposed to cover the bent display panel and the exposed microcoating layer.

[0253] According to some embodiments of the present disclosure, the flexible display device may further include an inner sealant that fills an inner space of the bent display panel and is disposed on an inner surface of the bending area.

[0254] According to some embodiments herein, the inner sealant may be disposed on one side edge of the flexible display device where the display panel is bent.

[0255] According to some embodiments herein, the traces may be formed of a ductile conductive material.

[0256] According to some embodiments of the present specification, the bending area may be formed by bending a portion of the non-display area in a bending direction, and at least a portion of the wiring is arranged to extend in a diagonal direction at least in the bending area, and the diagonal direction may be different from the bending direction.

[0257] According to some embodiments herein, the thickness of the microcoating layer at the bending location of the bending region may be less than the thickness at other locations.

[0258] According to some embodiments herein, the microcoating layer may have a thickness of 70 μm to 130 μm.

[0259] A flexible display device according to another embodiment of the present specification may include a display panel including a display region, a non-display region including a curved bending region, a plurality of wirings extending into the bending region and a plurality of sub-pixels arranged in the display region, and a circuit element including terminals connected to the display panel by the plurality of wirings.

[0260] According to some embodiments herein, the plurality of wires may include metal nanowires, metal mesh, or carbon nanotubes (CNTs).

[0261] According to some embodiments of the present disclosure, each of the plurality of traces may be formed in one of a trapezoidal wave shape, a triangular wave shape, a sawtooth wave shape, a sine wave shape, an omega (Ω) shape, and a diamond shape.

[0262] According to some embodiments of the present disclosure, the flexible display device may further include a cover glass, and an outer sealant disposed on the cover glass and covering an outer surface of the bending region.

[0263] According to some embodiments of the present disclosure, the flexible display device may further include an inner sealant, the inner surface of the bending area being located opposite the outer surface of the bending area and sealing the inner surface of the bending area.

[0264] According to some embodiments of the present disclosure, the display panel may further include a thin film transistor and a planarization layer disposed on the thin film transistor.

[0265] According to some embodiments of the present disclosure, the display panel may further include a light emitting element, and an intermediate electrode that connects the thin film transistor and the light emitting element and is disposed on any one of the planarization layers.

[0266] A manufacturing method for a flexible display device according to an embodiment of the present specification may include a step of forming a plurality of wirings in a non-display area of ​​the display panel extending to the display area, and a step of forming a reflective layer under the plurality of wirings in the non-display area between the display area and the bending area.

[0267] Although the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications can be made within the scope of the technical idea of ​​the present invention. Therefore, the embodiments disclosed in the present invention are for illustration purposes, not for 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. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not limiting. The scope of protection of the present invention should be interpreted by the scope of the claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention. [Explanation of symbols]

[0268] 100 Flexible display device 110 Display Panel 111 Substrate

Claims

1. a display panel including a display area and a non-display area, the non-display area including a bending area; A plurality of light-emitting elements arranged in the display area of ​​the display panel; a plurality of wirings disposed in the non-display area of ​​the display panel and extending into the display area; a reflective layer disposed under the wiring in the non-display region between the display region and the bending region; Including, the display panel includes a first planar portion, a second planar portion, and a curved portion between the first planar portion and the second planar portion, the reflective layer is disposed only on a portion of the first planar portion of the display panel between the display area and the bending area; Flexible display devices.

2. a planarization layer disposed on top of the wiring; a microcoating layer disposed on top of the planarization layer in the bending region; The flexible display device of claim 1 further comprising:

3. The flexible display device of claim 1 , wherein the reflective layer is disposed over the plurality of traces.

4. The flexible display device according to claim 1 , wherein the reflective layer is disposed over the entire non-display area in a plan view of the flexible display device.

5. the first flat portion corresponds to the display area and a first area of ​​the non-display area and maintains a flat state; the second planar portion corresponds to a second region different from the first region of the non-display region and faces the first planar portion; The flexible display device of claim 1 , wherein the curved surface portion corresponds to the bending region and maintains a bent state with a predetermined curvature.

6. The flexible display device of claim 2 , further comprising a cover glass disposed on the display panel.

7. The flexible display device of claim 6 , further comprising an outer sealant disposed on a lower edge of the cover glass and disposed to cover an outer surface of the bending area.

8. The flexible display device of claim 7 , further comprising a light-shielding layer disposed on the bottom edge of the cover glass.

9. The flexible display of claim 7 , wherein the outer sealant is disposed over the exposed microcoating layer.

10. The flexible display device of claim 9 , further comprising an inner sealant that fills an inner space of the bent display panel and is disposed on an inner surface of the bending area.

11. The flexible display device of claim 10 , wherein the inner sealant is disposed on one side edge of the flexible display device where the display panel is bent.

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