Display device

Abstract

The utility model provides a display device. The display device defines a display area, and includes: a display panel in the display area; a cover window disposed on an upper surface of the display panel; and a protective member disposed on a lower surface of the display panel in the display area. The material of the protective member has an elastic modulus of 4 GPa or less at the glass transition temperature of the material and a shrinkage rate of 20% or more at the glass transition temperature.

Description

Technical Field

[0001] The present disclosure relates to a display device. Background Art

[0002] As information-oriented society develops, various demands on display devices are increasing. For example, display devices are being adopted by various electronic devices such as smart phones, digital cameras, laptop computers, navigation devices, and smart TVs.

[0003] Various display devices such as liquid crystal display (LCD) devices and organic light emitting display (OLED) devices are currently being used. Organic light emitting display devices display images by using organic light emitting elements that emit light through the recombination of electrons and holes. Such organic light emitting display devices include transistors for providing driving current to the organic light emitting elements.

[0004] Various designs of the appearance of the display device are adopted in the electronic device. For example, the display device may have a front surface with a curved edge and a corner in which an image may be displayed. The curved edge and corner of the display device may be formed by deforming the edge and corner using an extrusion process. Since the layers of the display device are bent in the extrusion process, wrinkles may appear on the deformed surface of the corner in the display device. Utility Model Content

[0005] Aspects of the present disclosure provide a display device capable of preventing adhesion failure at a corner and a method of manufacturing the display device.

[0006] It should be noted that the objects of the present disclosure are not limited to the above objects; and other objects of the present disclosure will be apparent to those skilled in the art from the following description.

[0007] According to aspects of the present disclosure, a display device defines a display area and includes: a display panel in the display area; a cover window disposed on an upper surface of the display panel; and a protective member disposed on a lower surface of the display panel in the display area. The material of the protective member has an elastic modulus of 4 GPa or less at a glass transition temperature of the material and a shrinkage rate of 20% or more at the glass transition temperature.

[0008] In an embodiment, the display area includes: a flat front surface; a pair of first side surfaces, respectively extending outward from first relative edges of the flat front surface and curved with a first curvature; a pair of second side surfaces, respectively extending outward from second relative edges of the flat front surface and curved with a second curvature, the first relative edges are spaced apart from each other in a first direction, and the second relative edges are spaced apart from each other in a second direction intersecting the first direction; and a plurality of corner portions, each corner portion being located in a space between a corresponding one of the pair of first side surfaces and a corresponding one of the pair of second side surfaces, and including a first curvature and a second curvature, a corresponding one of the pair of first side surfaces being adjacent to a corresponding one of the pair of second side surfaces.

[0009] In an embodiment, the protection member is attached to the lower surface of the display panel corresponding to the flat front surface, the pair of first side surfaces, the pair of second side surfaces, and the plurality of corner portions.

[0010] In an embodiment, the display device further includes a first coupling layer disposed in a space between the display panel and the protection member, and a second coupling layer disposed in a space between the display panel and the cover window.

[0011] In an embodiment, the glass transition temperature of the protection member is selected from the range of 50 to 150 degrees Celsius.

[0012] In an embodiment, at a glass transition temperature selected from the range of 74 to 78 degrees Celsius, the elastic modulus of the protection member corresponds to an elastic modulus selected from the range of 0.6 to 0.9 GPa.

[0013] In an embodiment, the material of the protection member includes at least one of a polyolefin-based resin, a polyethylene-based resin, a polyethylene-based resin, and a polyester-based resin.

[0014] In an embodiment, the protection member has a thickness selected from the range of 25 μm to 100 μm.

[0015] According to an aspect of the present disclosure, a display device is defined with a display area and a bonding area spaced apart from the display area, and includes: a display panel in the display area and the bonding area; a cover window disposed on the display panel in the display area; a first protective member disposed under the display panel in the display area; and a second protective member disposed under the display panel in the bonding area and spaced apart from the first protective member. The shrinkage rate of the second protective member is less than the shrinkage rate of the first protective member.

[0016] In an embodiment, the shrinkage rate of the second protective member and the shrinkage rate of the first protective member are measured at a temperature selected from a temperature range of 50 to 150 degrees Celsius.

[0017] In an embodiment, a shrinkage rate of the second protective member is 1% or less at a temperature selected from a temperature range of 50 to 150 degrees Celsius.

[0018] In an embodiment, the second protective member has a thermal expansion coefficient of 30 ppm / ° C. or less at a temperature selected from a temperature range of room temperature to 180 degrees Celsius.

[0019] In an embodiment, the melting point of the second protective member is equal to or greater than 180 degrees Celsius.

[0020] In an embodiment, at a temperature selected from a temperature range of 50 to 150 degrees Celsius, an elastic modulus of the second protective member is greater than an elastic modulus of the first protective member.

[0021] In an embodiment, the second protective member has an elastic modulus of 4.5 GPa or more at a temperature selected from a temperature range of 50 to 150 degrees Celsius.

[0022] According to aspects of the present disclosure, a method for manufacturing a display device includes: preparing a display panel, a first protective member, and a second protective member; attaching the first protective member and the second protective member to the lower surface of the display panel so that the first protective member is separated from the second protective member on the lower surface of the display panel; aligning a cover window on the upper surface of the display panel and aligning a guide member on the lower surface of the display panel; pressing the cover window and the guide member against the upper and lower surfaces of the display panel, respectively; after pressing, heating the display panel and the first protective member by the guide member; and removing the guide member. The elastic modulus of the second protective member is greater than the elastic modulus of the first protective member.

[0023] In an embodiment, the guide member includes: a flat portion; a pair of first curved portions extending outward from first relative edges of the flat portion and curved with a first curvature; a pair of second curved portions extending outward from second relative edges of the flat portion and curved with a second curvature, the first relative edges being spaced apart from each other in a first direction, and the second relative edges being spaced apart from each other in a second direction intersecting the first direction; and a plurality of hyperbolic portions, each hyperbolic portion being located in a space between a corresponding one of the pair of first curved portions and a corresponding one of the pair of second curved portions, and including a first curvature and a second curvature, and a corresponding one of the pair of first curved portions and a corresponding one of the pair of second curved portions being adjacent to each other.

[0024] In an embodiment, the guide member includes a plurality of first heaters disposed at the plurality of hyperbolic portions, and the plurality of first heaters apply heat to the display panel and the first protection member.

[0025] In an embodiment, the guide member further includes a plurality of second heaters disposed at the pair of first bent portions and the pair of second bent portions, and the plurality of second heaters apply heat to the display panel and the first protective member.

[0026] In an embodiment, at a temperature selected from a temperature range of 50 to 150 degrees Celsius, a shrinkage rate of the second protective member is smaller than a shrinkage rate of the first protective member.

[0027] According to the embodiments of the present disclosure, it is possible to prevent adhesion failure between a display panel and a protective member in a display device when the protective member is deformed at a corner having a double curvature. Therefore, it is possible to prevent warping defects between the display panel and the protective member, thereby preventing cracks and disconnections of the display panel.

[0028] It should be noted that the effects of the present disclosure are not limited to those described above, and other effects of the present disclosure will be apparent to those skilled in the art from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and other aspects and features of the present disclosure will become more apparent by describing in detail embodiments of the present disclosure with reference to the attached drawings.

[0030] Figure 1 is a perspective view showing a display device according to an embodiment of the present disclosure.

[0031] Figure 2 is a plan view showing a display device according to an embodiment of the present disclosure.

[0032] Figure 3 is a diagram showing an embodiment of the present disclosure Figure 2 1 is a cross-sectional view of the display panel taken along line Q1 - Q1 ′.

[0033] Figure 4 is a plan view schematically showing pixels of a display area of ​​a display device according to an embodiment of the present disclosure.

[0034] Figure 5 According to the embodiment of the present disclosure, Figure 4 A cross-sectional view taken along line Q2-Q2'.

[0035] Figure 6 is a plan view showing a display panel of a display device according to an embodiment of the present disclosure.

[0036] Figure 7 According to the embodiment of the present disclosure, Figure 6 A cross-sectional view taken along line Q3-Q3'.

[0037] Figure 8According to the embodiment of the present disclosure, Figure 6 A cross-sectional view taken along line Q3-Q3'.

[0038] Fig. 9 is a flowchart for illustrating a method for manufacturing a display device according to an embodiment of the present disclosure.

[0039] Fig.10 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure.

[0040] Fig.11 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure.

[0041] Fig.12 is a perspective view showing a guide member according to an embodiment.

[0042] Fig.13 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure.

[0043] Fig.14 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure.

[0044] Fig.15 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure.

[0045] Fig.16 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure.

[0046] Fig.17 is a perspective view showing a guide member according to an embodiment.

[0047] Fig.18 is a graph showing glass transition temperatures of samples of protection members according to an embodiment of the present disclosure.

[0048] Fig.19 is a graph showing elastic modulus at glass transition temperature of samples of the protection member according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0049] The present application will now be described more fully below with reference to the accompanying drawings, in which preferred embodiments of the present application are shown. However, the present application may be implemented in different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure will be thorough and complete, and the scope of the present application will be fully conveyed to those skilled in the art.

[0050] It will also be understood that when a layer is referred to as being 'on' another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Like reference numerals refer to like components throughout the specification.

[0051] It will be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the teachings of the present application, the first element discussed below may be referred to as the second element. Similarly, the second element may also be referred to as the first element.

[0052] Each of the features of the various embodiments of the present disclosure can be combined in part or in whole or in combination with each other, and can be technically interlocked and driven in various ways. Each embodiment can be implemented independently of each other, or can be implemented together in association.

[0053] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0054] Figure 1 is a perspective view showing a display device according to an embodiment of the present disclosure. Figure 2 is a plan view showing a display device according to an embodiment of the present disclosure.

[0055] refer to Figure 1 and Figure 2 , the display device 10 according to the present embodiment may include various devices for displaying images or videos. For example, in addition to smart phones, the display device 10 according to the embodiment of the present disclosure may also be applied to mobile phones, tablet PCs, personal digital assistants (PDAs), portable multimedia players (PMPs), television sets, game consoles, watch-type electronic devices, head-mounted displays, personal computer monitors, laptop computers, car navigation systems, car dashboards, digital cameras, video cameras, outdoor billboards, electronic billboards, various medical devices, various home appliances such as refrigerators and washing machines, Internet of Things (IoT) devices, etc.

[0056] As used herein, when viewed from the top, the shorter side of the display device 10 may extend in parallel to the first direction DR1, and the longer side of the display device 10 may extend in parallel to the second direction DR2. For example, the first direction DR1 and the second direction DR2 may intersect each other so that they are perpendicular to each other, the first direction DR1 may correspond to the horizontal direction of the display device 10 when viewed from the top, and the second direction DR2 may correspond to the vertical direction of the display device 10 when viewed from the top. For example, the third direction DR3 may be perpendicular to the first direction DR1 and the second direction DR2, and may refer to the thickness direction of the display device 10.

[0057] The display device 10 may include a display area DA and a non-display area NDA.

[0058] In the display area DA, an image may be displayed. The display area DA may include pixels and / or emission areas. The display area DA may include a front surface FS, a side surface SS, and a corner portion CS, the side surface SS may include a first side surface SS1, a second side surface SS2, a third side surface SS3, and a fourth side surface SS4, and the corner portion CS may include a first corner portion CS1, a second corner portion CS2, a third corner portion CS3, and a fourth corner portion CS4. The front surface FS, the side surface SS, and the corner portion CS may basically include a cover window CW (see FIG. 1 ) to be described below. Figure 3 )middle.

[0059] The entire front surface FS may be substantially flat, but the present disclosure is not limited thereto. At least a portion of the front surface FS may include a convex shape or a concave shape in the thickness direction (third direction DR3). The front surface FS may include a rectangular shape having a shorter side in the first direction DR1 and a longer side in the second direction DR2. When viewed from the top, the front surface FS may have rounded corners. When viewed from the top, the front surface FS may have rounded polygonal corners. For example, Figure 1 As shown in , the front surface FS may have a rectangular shape with rounded corners, but the present disclosure is not limited thereto.

[0060] The side surface SS may extend outward from the edges BL1, BL2, BL3, and BL4 of the front surface FS, and may be bent downward at a predetermined angle. For example, the side surface SS may be bent downward from the front surface FS at an angle equal to or greater than 90 degrees and less than 180 degrees. In the case where the front surface FS has a rectangular shape when viewed from the top, the side surface SS may include a first side surface SS1 and a third side surface SS3 extending in a first direction DR1 from two opposite sides of the front surface FS, respectively, and may include a second side surface SS2 and a fourth side surface SS4 extending from two opposite sides of the front surface FS, respectively. The first side surface SS1 and the third side surface SS3 may refer to a first pair of side surfaces, and the second side surface SS2 and the fourth side surface SS4 may refer to a second pair of side surfaces. Except for the position, the first side surface SS1, the second side surface SS2, the third side surface SS3, and the fourth side surface SS4 may have substantially the same function or configuration.

[0061] When viewed from the top, each of the first side surface SS1, the second side surface SS2, the third side surface SS3, and the fourth side surface SS4 may have, but is not limited to, a rounded shape. For example, the first side surface SS1 may include a rounded shape on one side and an opposite side in the second direction DR2, respectively. However, the present disclosure is not limited thereto.

[0062] The first side surface SS1, the second side surface SS2, the third side surface SS3, and the fourth side surface SS4 may extend from the front surface FS to have a predetermined curvature and may have a rounded shape. The first side surface SS1, the second side surface SS2, the third side surface SS3, and the fourth side surface SS4 may have a convex shape toward the outside of the display device 10. For example, the first side surface SS1 may include a first curvature, and the second side surface SS2 may include a second curvature. The third side surface SS3 may include a third curvature, and the fourth side surface SS4 may include a fourth curvature. The first to fourth curvatures may all be equal, but the present disclosure is not limited thereto. The first to fourth curvatures may be different from each other, or only some of the first to fourth curvatures may be equal to each other. In some embodiments, the first curvature and the third curvature may be the same. In some embodiments, the second curvature and the fourth curvature may be the same.

[0063] A portion bent outward from the front surface FS of the display device 10 between adjacent side surfaces SS is defined as a corner portion CS. The first side surface SS1, the second side surface SS2, the third side surface SS3, and the fourth side surface SS4 may be spaced apart from each other at a corner of the front surface FS. The corner portion CS may be located at a corner where the first side surface SS1, the second side surface SS2, the third side surface SS3, and the fourth side surface SS4 are spaced apart from each other.

[0064] For example, the first corner portion CS1 may be disposed in a space between the first side surface SS1 and the second side surface SS2, the second corner portion CS2 may be disposed in a space between the second side surface SS2 and the third side surface SS3, the third corner portion CS3 may be disposed in a space between the third side surface SS3 and the fourth side surface SS4, and the fourth corner portion CS4 may be disposed in a space between the fourth side surface SS4 and the first side surface SS1. The first corner portion CS1 may connect the first side surface SS1 and the second side surface SS2 to each other. The second corner portion CS2 may connect the second side surface SS2 and the third side surface SS3 to each other. The third corner portion CS3 may connect the third side surface SS3 and the fourth side surface SS4 to each other. The fourth corner portion CS4 may connect the fourth side surface SS4 and the first side surface SS1 to each other. Except for the position, the first corner portion CS1, the second corner portion CS2, the third corner portion CS3, and the fourth corner portion CS4 may have substantially the same function or configuration.

[0065] The first corner portion CS1, the second corner portion CS2, the third corner portion CS3 and the fourth corner portion CS4 may all include the curvature of the adjacent side surfaces and may have a rounded shape. For example, the first corner portion CS1 may be located between the first side surface SS1 and the second side surface SS2. In this case, the first corner portion CS1 may have a double curvature including a first curvature of the first side surface SS1 and a second curvature of the second side surface SS2 that is different from the first curvature. For example, the curvature of the first corner portion CS1 may vary from the first curvature to the second curvature. At the first boundary between the first corner portion CS1 and the first side surface SS1, the curvature of the first corner portion CS1 may correspond to the first curvature. At the second boundary between the first corner portion CS1 and the second side surface SS2, the curvature of the first corner portion CS1 may correspond to the second curvature. Between the first boundary and the second boundary, the curvature of the first corner portion CS1 may correspond to the curvature between the first curvature and the second curvature. The foregoing description of the first corner portion CS1 may also be applied to the second corner portion CS2, the third corner portion CS3, and the fourth corner portion CS4. However, the present disclosure is not limited thereto. The first curvature and the second curvature may be the same, and the entire first corner portion CS1 may have the same curvature.

[0066] Pixels may be provided at the corner portion CS as well as the front surface FS and the side surface SS of the display device 10, and an image may be displayed at the corner portion CS. Therefore, when a user views the display device 10 from the front, the user may recognize that an image is displayed in the entire area of ​​the display device 10. The user may recognize the display device 10 as if there is substantially no frame and may experience more immersive content.

[0067] The image may not be displayed in the non-display area NDA. The non-display area NDA may not include pixels or emission areas. In the non-display area NDA, a signal line or a scan driver for driving the pixels or emission areas may be provided. The non-display area NDA may surround the display area DA. The non-display area NDA may be provided outside the front surface FS and the side surface SS and outside the corner portion CS. The non-display area NDA may form a frame of the display device 10.

[0068] Figure 3 It is shown along Figure 2 1 is a cross-sectional view of an example of a display panel taken along line Q1 - Q1 ′.

[0069] refer to Figure 3 , the display device 10 may include a protection member PRL, a substrate SUB, a display layer DISL, a sensor layer SENL and / or a cover window CW.

[0070] The substrate SUB may be made of a flexible insulating material such as a polymer resin and glass. For example, the substrate SUB may be a flexible substrate that can be bent, folded, or curled. In some embodiments, the substrate SUB may include or may be formed of polyimide. The substrate SUB may provide a space in which other elements disposed on the substrate SUB may be positioned, and may support other elements disposed thereon.

[0071] The display layer DISL may be disposed on the substrate SUB. The display layer DISL may include a display area DA and a non-display area NDA. In addition to the emission area, a scan line, a data line, a power line, etc. for driving the light emitting element may be disposed in the display area DA of the display layer DISL. In the non-display area NDA of the display layer DISL, a scan driver circuit for outputting a scan signal to the scan line, a fan-out line connecting the data line to the driver circuit, etc. may be disposed.

[0072] The display layer DISL may include a pixel circuit layer in which a thin film transistor to be described later is formed, an emission material layer in which a light emitting element emitting light is provided in an emission region, and an encapsulation layer for encapsulating the emission material layer.

[0073] The sensor layer SENL may be disposed on the display layer DISL. The sensor layer SENL may include sensor electrodes. The sensor layer SENL may sense whether there is a touch of a person or an object using the sensor electrodes.

[0074] The cover window CW may be disposed on the sensor layer SENL. The cover window CW may be attached to the sensor layer SENL by a transparent adhesive such as an optically clear adhesive (OCA) and an optically clear resin (OCR). The cover window CW may be either an inorganic material such as glass or an organic material such as plastic and a polymer material. The cover window CW may include a front surface FS, a side surface SS, and a corner portion CS. In some embodiments, the cover window CW may cover the display layer DISL without covering the bonding area BON (see Figure 6 In some embodiments, the cover window CW may cover the entire area of ​​the display layer DISL without covering any area of ​​the bonding area BON.

[0075] The protection member PRL may protect the lower surface of the display panel 300 from external influences and may maintain the shape of the display panel 300. In some embodiments, the protection member PRL may be a rigid layer to prevent the shape of the display panel 300 from being deformed during the manufacturing process of the display device 10.

[0076] Figure 4 is a plan view schematically showing a pixel in a display region of the display device according to the present embodiment. Figure 5 It is along Figure 4A cross-sectional view taken along line Q2-Q2'.

[0077] refer to Figure 4 , the display area DA of the display panel 300 may include a plurality of pixels PX. Each of the pixels PX may include a plurality of emission areas EA1, EA2, EA3, and EA4. For example, each of the pixels PX may include a first emission area EA1, a second emission area EA2, a third emission area EA3, and a fourth emission area EA4. The first emission area EA1, the second emission area EA2, the third emission area EA3, and the fourth emission area EA4 may emit light of different colors. However, it should be understood that the present disclosure is not limited thereto. For example, the first emission area EA1 may emit red light, the third emission area EA3 may emit blue light, and the second emission area EA2 and the fourth emission area EA4 may emit green light.

[0078] Reference Figure 5 Describe the cross-sectional structure of the pixel PX. The first coupling layer 401 may be disposed on the protection member PRL, and the substrate SUB may be disposed on the first coupling layer 401. The display layer DISL including the pixel circuit layer PCL, the emission material layer EML, and the encapsulation layer TFEL may be disposed on the substrate SUB, and the sensor layer SENL including the driving electrode TE, the sensing electrode RE, and the contact bridge electrode BE may be disposed on the display layer DISL.

[0079] The protection member PRL may protect the lower surface of the display panel 300 from external influences and may help maintain the shape of the display panel 300. In some embodiments, the protection member PRL may be used to maintain the shape of the display panel 300 during the manufacturing process of the display device 10.

[0080] The first coupling layer 401 may adhere the protection member PRL to other elements. The first coupling layer 401 may be made of a material capable of adhering to the protection member PRL. For example, the lower surface of the first coupling layer 401 may be in direct contact with the upper surface of the protection member PRL and may be attached to the upper surface of the protection member PRL. The first coupling layer 401 may be an adhesive layer. The first coupling layer 401 may include or may be formed of an optically transparent material made of silicon, but is not limited thereto. For example, the first coupling layer 401 may include or may be formed of a silicon-based optically transparent adhesive (OCA).

[0081] The substrate SUB may include a flexible substrate capable of being bent, folded, rolled, and / or stretched as described above.

[0082] The pixel circuit layer PCL may be disposed on the substrate SUB and may include a first thin film transistor ST1, a pixel connection electrode ANDE1, a capacitor CAP, a buffer layer BF1, a gate insulator 130, a first interlayer dielectric layer 141, a second interlayer dielectric layer 142, a first planarization layer 150, and a second planarization layer 160.

[0083] The buffer layer BF1 may be disposed on the substrate SUB. The buffer layer BF1 may be formed of a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0084] The first thin film transistor ST1 may be disposed on the buffer layer BF1. The first thin film transistor ST1 may include a first active layer ACT1, a first gate electrode G1, a first source electrode S1, and a first drain electrode D1.

[0085] The first active layer ACT1 of the first thin film transistor ST1 may be disposed on the buffer layer BF1. The first active layer ACT1 may include or may be formed of a silicon semiconductor such as polycrystalline silicon, single crystal silicon, low temperature polycrystalline silicon, or amorphous silicon. A portion of the first active layer ACT1 that overlaps with the first gate electrode G1 in the third direction DR3 may be defined as a channel region. Another portion of the first active layer ACT1 that does not overlap with the first gate electrode G1 in the third direction DR3 may be defined as a conductive region. By doping the silicon semiconductor with ions or impurities, the conductive region of the first active layer ACT1 may have conductivity.

[0086] The gate insulator 130 may be disposed on the first active layer ACT1 of the first thin film transistor ST1. The gate insulator 130 may be formed of an inorganic layer (eg, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer).

[0087] The first gate electrode G1 of the first thin film transistor ST1 and the first capacitor electrode CAE1 of the capacitor CAP may be disposed on the gate insulator 130. The first gate electrode G1 of the first thin film transistor ST1 may overlap the first active layer ACT1 in the third direction DR3. The first capacitor electrode CAE1 may overlap the second capacitor electrode CAE2 of the capacitor CAP in the third direction DR3 (e.g., z-axis direction). The first gate electrode G1 and the first capacitor electrode CAE1 may be formed of a single layer or a multilayer thereof formed of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), and alloys thereof. In some embodiments, the first gate electrode G1 and the first capacitor electrode CAE1 may be formed of the same material. In some embodiments, the first gate electrode G1 and the first capacitor electrode CAE1 may be patterned by the same layer in the same process.

[0088] The first interlayer dielectric layer 141 may be disposed on the first gate electrode G1 and the first capacitor electrode CAE1. The first interlayer dielectric layer 141 may be formed of an inorganic layer (eg, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer). The first interlayer dielectric layer 141 may include a plurality of inorganic layers.

[0089] The second capacitor electrode CAE2 may be disposed on the first interlayer dielectric layer 141. The second capacitor electrode CAE2 may overlap the first capacitor electrode CAE1 in the third direction DR3. Since the first interlayer dielectric layer 141 has a predetermined dielectric constant, a capacitor CAP may be formed by the first capacitor electrode CAE1, the second capacitor electrode CAE2, and the first interlayer dielectric layer 141. The second capacitor electrode CAE2 may be formed of a single layer or a multilayer formed of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), and alloys thereof.

[0090] The second interlayer dielectric layer 142 may be disposed throughout the second capacitor electrode CAE2. The second interlayer dielectric layer 142 may be formed of an inorganic layer (eg, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer).

[0091] The first source electrode S1 and the first drain electrode D1 of the first thin film transistor ST1 may be disposed on the second interlayer dielectric layer 142. The first source electrode S1 and the first drain electrode D1 may be formed of a single layer or a multilayer of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), and alloys thereof. In some embodiments, the first source electrode S1 and the first drain electrode D1 may be formed of the same material. In some embodiments, the first source electrode S1 and the first drain electrode D1 may be formed of the same layer using the same process.

[0092] The first source electrode S1 of the first thin film transistor ST1 may be connected to a conductive region located on one side of the channel region of the first active layer ACT1 through a contact hole passing through the gate insulator 130, the first interlayer dielectric layer 141, and the second interlayer dielectric layer 142. The first drain electrode D1 of the first thin film transistor ST1 may be connected to a conductive region located on an opposite side of the channel region of the first active layer ACT1 through a contact hole passing through the gate insulator 130, the first interlayer dielectric layer 141, and the second interlayer dielectric layer 142.

[0093] The first planarization layer 150 may be disposed on the first source electrode S1 and the first drain electrode D1 to provide a flat surface throughout the thin film transistors having different heights. The first planarization layer 150 may be formed of an organic layer such as acrylic resin, epoxy resin, phenolic resin, polyamide resin, or polyimide resin.

[0094] The pixel connection electrode ANDE1 may be disposed on the first planarization layer 150. The pixel connection electrode ANDE1 may be connected to the first source electrode S1 or the first drain electrode D1 of the first thin film transistor ST1 through a contact hole penetrating the first planarization layer 150. The pixel connection electrode ANDE1 may be formed of a single layer or a multilayer formed of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), and alloys thereof.

[0095] The second planarization layer 160 may be disposed on the pixel connection electrode ANDE1. The second planarization layer 160 may be formed of an organic layer such as acrylic resin, epoxy resin, phenol resin, polyamide resin, or polyimide resin.

[0096] The barrier layer 161 may be disposed on the second planarization layer 160. The barrier layer 161 may be formed of a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0097] The emission material layer EML may be disposed on the pixel circuit layer PCL. The emission material layer EML may include a light emitting element 170 and a bank 180.

[0098] Each of the light emitting elements 170 may include a pixel electrode 171, an emission layer 172, and a common electrode 173. In each of the emission regions EA1, EA2, EA3, and EA4, the pixel electrode 171, the emission layer 172, and the common electrode 173 are sequentially stacked on each other so that holes from the pixel electrode 171 and electrons from the common electrode 173 are recombined with each other in the emission layer 172 to emit light. In this case, the pixel electrode 171 may be an anode electrode, and the common electrode 173 may be a cathode electrode. The first emission region EA1 and the fourth emission region EA4 may be substantially the same as the third emission region EA3.

[0099] The pixel electrode 171 may be disposed on the barrier layer 161. The pixel electrode 171 may be connected to the pixel connection electrode ANDE1 through a contact hole penetrating the barrier layer 161 and the second planarization layer 160.

[0100] In a top emission structure in which light is emitted from the emission layer 172 toward the common electrode 173, the pixel electrode 171 may be composed of a stacked structure (ITO / Al / ITO) of an ITO (indium tin oxide) layer having a high work function, an aluminum layer for reflecting light, and an ITO layer having high adhesion. In some embodiments, the ITO layer disposed on the opposite side of the Al layer may have both a high work function and high adhesion.

[0101] The bank 180 is used to define each of the emission areas EA1, EA2, EA3, and EA4 of the display pixel. To this end, the bank 180 may be formed on the barrier layer 161 to expose a portion of the pixel electrode 171. The bank 180 may cover the edge of the pixel electrode 171. The bank 180 may be formed of an organic layer such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0102] The emission layer 172 may be disposed on the pixel electrode 171. The emission layer 172 may include an organic material or may be formed therefrom to emit light of a specific color. For example, the emission layer 172 may include a hole transport layer, an organic material layer, and an electron transport layer. The organic material layer may include a host and a dopant. The organic material layer may include a material that emits a predetermined light and may be formed using a phosphor or a fluorescent material.

[0103] The common electrode 173 may be disposed on the emission layer 172. The common electrode 173 may cover the emission layer 172. The common electrode 173 may be a common layer formed across the display pixels. In some embodiments, the display pixels may share the common electrode 173. A capping layer may be formed on the common electrode 173.

[0104] In the top emission structure, the common electrode 173 may be thinly formed of a transparent conductive material (TCO) capable of reducing resistance and transmitting light and a metal having a low work function. For example, the TCO may include ITO or IZO (indium zinc oxide), and the metal having a low work function may include magnesium (Mg), silver (Ag), or an alloy of magnesium (Mg) and silver (Ag).

[0105] The encapsulation layer TFEL may be formed on the emission material layer EML. The encapsulation layer TFEL may include at least one inorganic layer to prevent oxygen or moisture from penetrating into the emission material layer EML. The encapsulation layer TFEL may include at least one organic layer to protect the emission material layer EML from particles. In some embodiments, the encapsulation layer TFEL may include at least one inorganic layer and at least one organic layer stacked on each other.

[0106] For example, the thin film encapsulation layer TFEL may include a first inorganic encapsulation film 191 disposed on the common electrode 173, an organic encapsulation film 192 disposed on the first inorganic encapsulation film 191, and a second inorganic encapsulation film 193 disposed on the organic encapsulation film 192. The first inorganic encapsulation film 191 and the second inorganic encapsulation film 193 may be composed of a single layer formed of a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer, or a multilayer stacked alternately with each other. The organic encapsulation film 192 may include an organic layer formed of an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin or may be formed thereof.

[0107] The sensor layer SENL is disposed on the encapsulation layer TFEL. The sensor layer SENL may include driving electrodes TE, sensing electrodes RE and contact bridge electrodes BE.

[0108] The first touch inorganic layer TINS1 may be disposed on the encapsulation layer TFEL. The first touch inorganic layer TINS1 may be formed as a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0109] The contact bridge electrode BE may be disposed on the first touch inorganic layer TINS1. The contact bridge electrode BE may be formed of a stack structure (ITO / Al / ITO) of an aluminum layer and an ITO layer.

[0110] The second touch inorganic layer TINS2 may be disposed on the contact bridge electrode BE. The second touch inorganic layer TINS2 may be formed as a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0111] The driving electrode TE and the sensing electrode RE may be disposed on the second touch inorganic layer TINS2. When overlapping with the emission areas EA1, EA2, EA3, and EA4, the driving electrode TE and the sensing electrode RE may block light and reduce the brightness of the light emitted from the emission areas EA1, EA2, EA3, and EA4. In order to prevent the light emitted from the emission areas EA1, EA2, EA3, and EA4 from being blocked by the driving electrode TE and the sensing electrode RE, the driving electrode TE and the sensing electrode RE do not overlap with the emission areas EA1, EA2, EA3, and EA4. The driving electrode TE and the sensing electrode RE may be formed of a stacked structure (Ti / Al / Ti) of an aluminum layer and a titanium layer.

[0112] The touch organic layer TINS3 may be disposed on the driving electrode TE and the sensing electrode RE. The touch organic layer TINS3 may include or be formed of acrylic resin, epoxy resin, phenol resin, polyamide resin, or polyimide resin.

[0113] The cover window CW may be disposed on the display panel 300. The cover window CW may be attached to the display panel 300 by a second coupling layer 402 disposed between the display panel 300 and the cover window CW. The second coupling layer 402 may include or may be formed of an acrylic optically clear adhesive (OCA). Therefore, the second coupling layer 402 may be optically transparent. The upper surface of the second coupling layer 402 may be in direct contact with the lower surface of the cover window CW, and may have the same area and shape as the lower surface of the cover window CW.

[0114] The protection member PRL may be disposed at the rear side of the display panel 300. The protection member PRL may overlap the display area DA of the display panel 300 to protect the lower surface of the display panel 300 from the outside and may maintain the shape of the display panel 300.

[0115] As described above, the display device 10 may include a side surface and a corner portion having a curvature. The corner portion of the display device 10 may have a double curvature with the curvature of the left and right surfaces and the curvature of the upper and lower surfaces, and therefore, such a shape of the display device 10 may require strain (i.e., deformation) on the protection member PRL and the display layer DISL. For example, in the process of attaching the protection member PRL to the display layer DISL, the protection member PRL and the display layer DISL may be deformed to align with each other at the corner portion having a double curvature. In such deformation of the protection member PRL, wrinkles may be formed on the deformed surface of the protection member PRL. During the process of attaching the display panel 300 to the protection member PRL, heat is applied to remove such wrinkles. Due to the difference in elastic modulus and shrinkage between the protection member PRL and the display panel 300, the protection member PRL may be detached from the display panel 300, thereby generating bubbles, i.e., warping may occur. If warping occurs in the protection member PRL, cracks may be generated in the display panel 300, and the line may be disconnected. As a result, display defects may occur.

[0116] According to an embodiment of the present disclosure, the protective member PRL may include or may be formed of a material having elasticity, so that the strain concentrated at the corner portion may be alleviated. For example, the protective member PRL may include a material that shrinks in a specific temperature environment so that it can be easily attached to the side surface and corner portion of the display device 10 having a curvature. For example, the protective member PRL may include or may be formed of one of a polyolefin-based resin, a polyethylene-based resin, a polyethylene-based resin, and a polyester-based resin. The protective member PRL may include or may be formed of a stretched polyester (e.g., polyethylene terephthalate (PET)). In some embodiments, the protective member PRL may include or may be formed of an elastic material to alleviate or straighten the wrinkles formed on the protective member PRL at the deformed portion of the protective member PRL corresponding to the corner portion of the display device 10 after heating.

[0117] The protection member PRL may have a predetermined thickness to support and protect the display panel 300. The protection member PRL may have a thickness of 100 μm or less (eg, 25 μm to 100 μm).

[0118] When heat is applied to the protective member PRL, the protective member PRL may shrink. The protective member PRL may have a shrinkage rate of 20% or more in a temperature range of 50 degrees Celsius to 150 degrees Celsius. For example, when heat is applied at a temperature of 85 degrees Celsius for about 10 minutes, the protective member PRL may exhibit a shrinkage rate of 30% or more. If the protective member PRL has a shrinkage rate of less than 20% in a temperature range of 50 to 150 degrees Celsius, there may be bending at the corner portion of the display device 10, resulting in warping between the display panel 300 and the protective member PRL. Therefore, the protective member PRL may have a shrinkage rate of 20% or more in a temperature range of 50 to 150 degrees Celsius to prevent warping. In some embodiments, the protective member PRL may have a shrinkage rate of 30% or more in a temperature range of 50 to 150 degrees Celsius to more effectively remove or straighten wrinkles caused by warping.

[0119] The protection member PRL shrinks together with other layers attached to the upper surface or the lower surface of the protection member PRL. For example, when the protection member PRL shrinks, the distance between molecules in the shrinking portion decreases. Therefore, the distance between molecules in the shrinking portion of the protection member PRL may be smaller than the distance between molecules in the non-shrinking portion of the protection member PRL. Therefore, the protection member PRL that has shrunk by receiving heat may have a higher density per unit volume than the protection member PRL that has not yet shrunk by receiving heat.

[0120] The protection member PRL may have a glass transition temperature (Tg) corresponding to a temperature selected from a range of 50 degrees Celsius to 150 degrees Celsius. For example, the material of the protection member PRL may have a glass transition temperature selected from a range of 50 degrees Celsius to 150 degrees Celsius. The protection member PRL may have an elastic modulus of 4 GPa or less in the range of the glass transition temperature (Tg) (e.g., a temperature range of 50 to 150 degrees Celsius). In some embodiments, the protection member PRL may have an elastic modulus of 4 GPa or less at the glass transition temperature (Tg). If the elastic modulus of the protection member PRL is equal to or less than 4 GPa, it has flexibility when heat is applied to the protection member PRL. Therefore, the bending at the corner of the display device 10 due to the double curvature can be prevented, and adhesion failure can be prevented. In some embodiments, the protection member PRL may have an elastic modulus of 3.6 GPa at room temperature (25 degrees Celsius). In some embodiments, the protection member PRL may exhibit a glass transition temperature corresponding to a temperature selected from the range of 74 to 78 degrees Celsius, and may have an elastic modulus of 2.5 GPa or less (more specifically, 0.6 to 0.9 GPa) in the temperature range of 74 to 78 degrees Celsius. In some embodiments, the protection member PRL having a glass transition temperature selected from the range of 74 to 78 degrees Celsius may have an elastic modulus selected from the range of 0.6 to 0.9 GPa at the glass transition temperature.

[0121] Therefore, the protection member PRL according to the present embodiment may satisfy the following characteristic conditions:

[0122] 1) a glass transition temperature corresponding to a temperature selected from the range of 50 to 150 degrees Celsius;

[0123] 2) an elastic modulus of 4 GPa or less at a temperature selected from the range of 50 to 150 degrees Celsius (in some embodiments, an elastic modulus of 4 GPa or less at the glass transition temperature); and

[0124] 3) A shrinkage of 20% or more at a temperature selected from the range of 50 to 150 degrees Celsius (in some embodiments, a shrinkage of 20% or more at the glass transition temperature).

[0125] As described above, according to the present embodiment, by using the protection member PRL satisfying the above-mentioned characteristic conditions, the generation of bubbles due to adhesion failure (ie, warpage) can be prevented, and the problems of cracks and disconnections in the display panel 300 can be improved.

[0126] Figure 6 is a plan view showing a display panel of a display device according to an embodiment of the present disclosure. Figure 7 It is along Figure 6A cross-sectional view taken along line Q3-Q3'.

[0127] Figure 6 and Figure 7 The implementation method and Figures 1 to 5 The embodiment of FIG. 4 is different in that the first protective member PRL1 is disposed on the display panel 300 in the display area DA, and the second protective member PRL2 is disposed on the display panel 300 in the bonding area BON.

[0128] The display device 10 according to the present embodiment may include a display panel 300. The display panel 300 may include a display area DA and a bonding area BON. The bonding area BON may be spaced apart from the display area DA and may overlap with a substrate SUB extending from the display area DA. As the flexible substrate SUB is bent, the display panel 300 corresponding to the bonding area BON may be located on the rear surface of the display panel 300 corresponding to the display area DA. The bonding area BON may include a driver circuit DIC. The driver circuit DIC may transmit a driving signal from an external device to the display area DA.

[0129] A first protective member PRL1 overlapping the display area DA and a second protective member PRL2 overlapping the bonding area BON may be disposed on the rear side of the substrate SUB. The first protective member PRL1 and the second protective member PRL2 may be spaced apart from each other. In some embodiments, the first protective member PRL1 and the second protective member PRL2 may be separated from each other. The first protective member PRL1 may support the display area DA to protect the lower surface of the display panel 300 from external influences, and the second protective member PRL2 may support the bonding area BON to protect the lower surface of the bonding area BON from external influences.

[0130] The first protective member PRL1 may be as described above with reference to Figures 1 to 5 The protective member PRL described. The second protective member PRL2 may include a resin having heat resistance or may be formed thereof. For example, the second protective member PRL2 may include a polyester-based resin or a polyimide-based resin or may be formed thereof. The polyester-based resin may include polyethylene terephthalate (PET) or may be formed thereof.

[0131] The driver circuit DIC may be mounted on the substrate SUB in the bonding area BON via an extrusion process. Because heat is applied to the bonding area BON in the extrusion process, the second protection member PRL2 may have heat resistance so that the shape of the second protection member PRL2 is not damaged (i.e., deformed) by heat. When the shape of the second protection member PRL2 is damaged or deformed by heat, the driver circuit DIC and the terminal in the bonding area BON may be misaligned, and thus a driving failure may occur.

[0132] According to an embodiment of the present disclosure, the second protective member PRL2 may have heat resistance and a low coefficient of thermal expansion (CTE). The coefficient of thermal expansion of the second protective member PRL2 may be equal to or less than 30ppm / °C at a temperature selected from the range from room temperature to 180 degrees Celsius. In some embodiments, the coefficient of thermal expansion of the second protective member PRL2 may be equal to or less than 30ppm / °C at a temperature selected from the range from room temperature to the melting temperature of the material of the second protective member PRL2. The lower the coefficient of thermal expansion, the smaller the volume changes as the temperature increases. Because the second protective member PRL2 has a low coefficient of thermal expansion of 30ppm / °C or less, it is possible to prevent deformation due to heat during the process of extruding the driver circuit DIC, thereby preventing misalignment of the driver circuit DIC.

[0133] The melting point of the second protection member PRL2 may be equal to or greater than 180 degrees Celsius. The melting point of a substance is the temperature at which it changes from a solid state to a liquid state. The higher the melting point of a substance, the stronger its heat resistance. Because the second protection member PRL2 has a melting point of 180 degrees Celsius or higher, it is possible to prevent the second protection member PRL2 from being damaged by heat during the extrusion process of the driver circuit DIC.

[0134] The second protection member PRL2 may have a smaller shrinkage rate than the first protection member PRL1. According to an embodiment of the present disclosure, the shrinkage rate of the second protection member PRL2 may be equal to or less than 1% in a temperature range of 50 to 150 degrees Celsius. The first protection member PRL1 should have a high shrinkage rate so as to be reliably attached to the lower surface of the substrate SUB, such as the side surface and the corner portion having a curvature. In contrast, the second protection member PRL2 should have a low shrinkage rate so as to withstand the heat applied during the process of pressing the driver circuit DIC while being attached to the lower surface of the substrate SUB, and so as to prevent misalignment between the driver circuit DIC and the terminal.

[0135] As a comparative example, when the second protective member PRL2 shrinks, other layers attached to the upper surface of the second protective member PRL2 may also shrink. In this case, during the above-mentioned process of squeezing the driver circuit DIC, the substrate SUB shrinks along with the second protective member PRL2, so that the terminals of the driver circuit DIC and the substrate SUB may be misaligned. According to an embodiment of the present disclosure, the second protective member PRL2 has a shrinkage rate of 1% or less in a temperature range of 50 to 150 degrees Celsius, and therefore, it is possible to prevent misalignment between the terminals of the driver circuit DIC and the substrate SUB during the process of squeezing the driver circuit DIC. For example, within the process margin of aligning the driver circuit DIC with the terminals of the substrate SUB, the shrinkage amount of the second protective member PRL2 with a shrinkage rate of 1% or less can be allowed.

[0136] The second protection member PRL2 may have a larger elastic modulus than the first protection member PRL1. The larger the elastic modulus, the smaller the strain may be even if the tensile stress increases. For example, as the elastic modulus increases, the protection member may become harder. The second protection member PRL2 may have a high elastic modulus so as to prevent misalignment between the terminal of the substrate SUB disposed thereon and the driver circuit DIC.

[0137] According to an embodiment of the present disclosure, the second protection member PRL2 may have an elastic modulus of 4.5 GPa or more at a process temperature (e.g., a temperature range of 50 to 150 degrees Celsius). In some embodiments, the elastic modulus of the second protection member PRL2 may be in the range of 4.5 to 5.5 GPa. If the elastic modulus of the second protection member PRL2 is equal to or greater than 4.5 GPa, the strain (or deformation) of the second protection member PRL2 may be reduced, and the deformation of the substrate SUB attached to the second protection member PRL2 may also be reduced. Therefore, misalignment between the terminal formed on the substrate SUB and the driver circuit DIC can be prevented, and thus driving defects can be prevented.

[0138] Therefore, the second protective member PRL2 according to the present embodiment may satisfy the following characteristic conditions:

[0139] 1) a melting point of the second protective member PRL2 corresponding to a temperature selected from the range of 180° C. or higher;

[0140] 2) a coefficient of thermal expansion of 30 ppm / °C or less at a first temperature selected from the range of room temperature to 180 degrees Celsius (in some embodiments, a coefficient of thermal expansion of 30 ppm / °C or less at a first temperature selected from the range of room temperature to the melting point);

[0141] 3) an elastic modulus of 4.5 GPa or more at a temperature selected from the range of 50 to 150 degrees Celsius (in some embodiments, an elastic modulus of 4.5 GPa or more at a glass transition temperature of the second protective member PRL2 corresponding to a temperature selected from the range of 50 to 150 degrees Celsius); and

[0142] 4) A shrinkage of 1% or less at a temperature selected from the range of 50 to 150 degrees Celsius (in some embodiments, a shrinkage of 1% or less at the glass transition temperature).

[0143] As described above, according to the present embodiment, by using the second protective member PRL2 satisfying the above-mentioned characteristic conditions, it is possible to prevent misalignment between the driver circuit DIC and the terminal in the bonding area BON during the process of bonding the driver circuit DIC, and thus driving defects caused by misalignment between the driver circuit DIC and the terminal of the substrate SUB can be avoided.

[0144] Figure 8 According to an exemplary embodiment, Figure 6 A cross-sectional view taken along line Q3-Q3'.

[0145] Figure 8 The implementation method and Figures 1 to 7 The embodiment of FIG. 3 is different in that a single protection member PRL is disposed at the rear side of the substrate SUB in the display area DA and the bonding area BON of the display panel 300 .

[0146] The display device 10 according to the present embodiment may include a protective member PRL overlapping the display area DA and the bonding area BON at the rear side of the substrate SUB of the display panel 300. The protective member PRL may extend from the display area DA of the display panel 300 to the bonding area BON of the display panel 300. The protective member PRL may support the display panel 300 in the display area DA and the bonding area BON, and may protect the lower surface of the display panel 300 from external influences.

[0147] As described above, the protective member PRL used in the display area DA requires a low thermal expansion coefficient and a low elastic modulus, while the protective member PRL used in the bonding area BON requires a low thermal expansion coefficient and a high melting point. According to this embodiment, the display device 10 is manufactured using a low temperature process in which the bonding process temperature of the driver circuit DIC is equal to or less than 50 degrees Celsius.

[0148] According to an embodiment of the present disclosure, a single protection member PRL is disposed at the rear side of the display panel 300 to simplify the structure and process, and the protection member PRL may satisfy the following features:

[0149] 1) A melting point corresponding to a temperature of 180°C or higher;

[0150] 2) a coefficient of thermal expansion of 30 ppm / °C or less at a temperature selected from the range of room temperature to 180 degrees Celsius (in some embodiments, a coefficient of thermal expansion of 30 ppm / °C or less at a temperature selected from the range of room temperature to the melting temperature);

[0151] 3) an elastic modulus of 2.5 GPa or less at a temperature selected from the range of 50 to 150 degrees Celsius (in some embodiments, an elastic modulus of 2.5 GPa or less at a glass transition temperature of the material of the protection member PRL corresponding to a temperature selected from the range of 50 to 150 degrees Celsius); and

[0152] 4) A shrinkage of 20% or less at a temperature selected from the range of 50 to 150 degrees Celsius (in some embodiments, a shrinkage of 20% or less at the glass transition temperature).

[0153] Fig. 9 is a flowchart for illustrating a method for manufacturing a display device according to an embodiment of the present disclosure.

[0154] refer to Fig. 9 , the method of manufacturing the display device 10 may include: preparing a display panel 300, a first protective member PRL1, and a second protective member PRL2 (step S100); attaching the first protective member PRL1 and the second protective member PRL2 to the display panel 300 (step S200); aligning the cover window CW on the display panel 300, and attaching a guide member HG (see Fig.13 ) is aligned under the display panel 300 (step S300); the cover window CW, the display panel 300 and the guide member HG are pressed (step S400); the display panel 300 and the first protective member PRL1 are heated by the guide member HG (step S500); and the guide member HG is removed (step S600).

[0155] In the following, we will combine Fig. 9 Flowchart reference Figures 10 to 17 A method of manufacturing the display device 10 will be described in detail.

[0156] Fig.10 is a view showing process steps of a method for manufacturing a display device according to an embodiment of the present disclosure; Fig.11 is a view showing process steps of a method for manufacturing a display device according to an embodiment of the present disclosure; Fig.12 is a perspective view showing a guide member according to an embodiment; Fig.13 is a view showing process steps of a method for manufacturing a display device according to an embodiment of the present disclosure; Fig.14is a view showing process steps of a method for manufacturing a display device according to an embodiment of the present disclosure; Fig.15 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure; and Fig.16 are views showing process steps of a method of manufacturing a display device according to an embodiment of the present disclosure.

[0157] refer to Fig.10 , the display panel 300 , the first protection member PRL1 , and the second protection member PRL2 are prepared (step S100 ). The first protection member PRL1 and the second protection member PRL2 may be aligned at the rear side of the display panel 300 .

[0158] The first protective member PRL1 may be as described above with reference to Figures 1 to 5 The protective member PRL described above, and the second protective member PRL2 may be as described above with reference to Figure 6 and Figure 7 The second protective member PRL2 described. For example, the first protective member PRL1 may have a shrinkage of 20% or more in a temperature range of 50 to 150 degrees Celsius, may exhibit a glass transition temperature (Tg) of 50 to 150 degrees Celsius, and may have an elastic modulus of 4 GPa or less in a temperature range of 50 to 150 degrees Celsius. The second protective member PRL2 may have a thermal expansion coefficient of 30 ppm / °C or less at a temperature selected from a range of room temperature to 180 degrees Celsius, may have a melting point of 180 degrees Celsius or more, and may have a shrinkage of 1% or less at a temperature selected from a temperature range of 50 to 150 degrees Celsius. In some embodiments, the second protective member PRL2 may have a thermal expansion coefficient of 30 ppm / °C or less at a temperature selected from a range of room temperature to a melting point, and may have a shrinkage of 1% or less at a first temperature selected from a temperature range of 50 to 150 degrees Celsius. In some embodiments, the first temperature selected from the temperature range may correspond to the glass transition temperature of the second protective member PRL2.

[0159] Subsequently, the first protection member PRL1 and the second protection member PRL2 are attached to the display panel 300 (step S200). The first protection member PRL1 may be attached to the rear side of the display panel 300 in the display area DA, and the second protection member PRL2 may be attached to the rear side of the display panel 300 in the bonding area BON. The adhesion between the first protection member PRL1 and the display panel 300 may be pre-bonded. They may be fully bonded during the bonding process to be described later. The first coupling layer 401 (see Figure 5) may be disposed on an upper surface of each of the first protection member PRL1 and the second protection member PRL2 so that the first protection member PRL1 and the second protection member PRL2 may be attached to the rear side of the display panel 300. The first coupling layer 401 may be, for example, a pressure sensitive adhesive (PSA).

[0160] Then, refer to Fig.11 , aligning the cover window CW on the display panel 300, and aligning the guide member HG under the display panel 300 (step S300). The cover window CW and the display panel 300 have been described above, and thus will not be described again to avoid redundancy. For example, the cover window CW may have a Figure 2 The front surface FS, the side surface SS, and the corner portion CS. In some embodiments, the cover window CW may be aligned to the upper surface of the display panel 300 corresponding to the display area DA, and the guide member HG may be aligned to the lower surface of the display panel 300 corresponding to the display area DA, and thus the cover window CW and the guide member HG may be pressed against the display panel 300 corresponding to the display area DA. In some embodiments, the cover window CW and the guide member HG may not cover the upper surface and the lower surface of the display panel 300 corresponding to the bonding area BON, respectively.

[0161] like Fig.12 As shown in , the guide member HG may have a shape similar to that of the cover window CW. For example, the guide member HG may include a base BS, a flat portion FFS, a curved portion SO, and a hyperbolic portion CO, the curved portion SO may include a first curved portion SO1, a second curved portion SO2, a third curved portion SO3, and a fourth curved portion SO4, and the hyperbolic portion CO may include a first hyperbolic portion CO1, a second hyperbolic portion CO2, a third hyperbolic portion CO3, and a fourth hyperbolic portion CO4. In some embodiments, the guide member HG may have a shape substantially the same as that of the cover window CW, and the size of the guide member HG may be smaller than that of the cover window CW, so that the guide member HG can be fitted into a space defined by the inner surface of the cover window CW under a pressure state of the cover window CW, the guide member HG, and the display panel 300, and the display panel 300 is between the guide member HG and the inner surface of the cover window CW.

[0162] The base BS may correspond to a body serving as a base for the flat portion FFS, the curved portion SO, and the hyperbolic portion CO. The base BS may form a bottom of the guide member HG.

[0163] The flat portion FFS may be a substantially flat area and may be aligned with the front surface FS of the cover window CW (see Figure 2). The flat portion FFS may include a rectangular shape having shorter sides in the first direction DR1 and longer sides in the second direction DR2. When viewed from the top, the flat portion FFS may have rounded corners.

[0164] The bent portion SO may extend outward from the edge of the flat portion FFS and may be bent downward at a predetermined angle. When the flat portion FFS has a rectangular shape when viewed from the top, the bent portion SO may include a first bent portion SO1 and a third bent portion SO3 extending from two opposite sides of the flat portion FFS in the first direction DR1, respectively, and may include a second bent portion SO2 and a fourth bent portion SO4 extending from two opposite sides of the flat portion FFS in the second direction DR2, respectively. The first bent portion SO1, the second bent portion SO2, the third bent portion SO3, and the fourth bent portion SO4 may be associated with the first side surface SS1, the second side surface SS2, the third side surface SS3, and the fourth side surface SS4 of the cover window CW, respectively. The first bent portion SO1, the second bent portion SO2, the third bent portion SO3, and the fourth bent portion SO4 may extend from the flat portion FFS to have a predetermined curvature and may have a rounded shape.

[0165] A portion of the guide member HG that is bent outward from the flat portion FFS between adjacent curved portions SO is defined as a hyperbolic portion CO. The first curved portion SO1, the second curved portion SO2, the third curved portion SO3, and the fourth curved portion SO4 may be spaced apart from each other at a corner of the flat portion FFS. The hyperbolic portion CO may be located at a corner where the first curved portion SO1, the second curved portion SO2, the third curved portion SO3, and the fourth curved portion SO4 are spaced apart from each other.

[0166] For example, the first hyperbolic portion CO1 may be disposed in a space between the first curved portion SO1 and the second curved portion SO2, the second hyperbolic portion CO2 may be disposed in a space between the second curved portion SO2 and the third curved portion SO3, the third hyperbolic portion CO3 may be disposed in a space between the third curved portion SO3 and the fourth curved portion SO4, and the fourth hyperbolic portion CO4 may be disposed in a space between the fourth curved portion SO4 and the first curved portion SO1. The first hyperbolic portion CO1 may connect the first curved portion SO1 and the second curved portion SO2 to each other, the second hyperbolic portion CO2 may connect the second curved portion SO2 and the third curved portion SO3 to each other, the third hyperbolic portion CO3 may connect the third curved portion SO3 and the fourth curved portion SO4 to each other, and the fourth hyperbolic portion CO4 may connect the fourth curved portion SO4 and the first curved portion SO1 to each other. The first hyperbolic portion CO1, the second hyperbolic portion CO2, the third hyperbolic portion CO3, and the fourth hyperbolic portion CO4 may be associated with the corner portion CS of the cover window CW, respectively.

[0167] The first hyperbolic portion CO1, the second hyperbolic portion CO2, the third hyperbolic portion CO3, and the fourth hyperbolic portion CO4 may include a hyperbolic curvature including the curvature of the adjacent curved portion SO, and may have a rounded shape. For example, the first hyperbolic portion CO1 may be located between the first curved portion SO1 and the second curved portion SO2. In this case, the first hyperbolic portion CO1 may have a hyperbolic curvature including a first curvature of the first curved portion SO1 and a second curvature of the second curved portion SO2 that is different from the first curvature. For example, the curvature of the first hyperbolic portion CO1 may change from the first curvature to the second curvature. At the first boundary between the first hyperbolic portion CO1 and the first curved portion SO1, the curvature of the first hyperbolic portion CO1 may correspond to the first curvature. At the second boundary between the first hyperbolic portion CO1 and the second curved portion SO2, the curvature of the first hyperbolic portion CO1 may correspond to the second curvature. Between the first boundary and the second boundary, the curvature of the first hyperbolic portion CO1 may correspond to the curvature between the first curvature and the second curvature.

[0168] The guide member HG as described above has a shape similar to that of the cover window CW, and as will be described later, presses the display panel 300 from below to reliably attach the first protective member PRL1 to the rear surface of the display panel 300 .

[0169] The guide member HG may further include a heater HT. The heater HT is used to radiate heat, and may include a component for radiating heat such as a coil and an infrared irradiation device. The heater HT may be provided at the curved portion SO and the hyperbolic portion CO of the guide member HG.

[0170] In some embodiments, the heater HT may include a first heater HT1 disposed at the hyperbolic portion CO and a second heater HT2 disposed at a portion of the curved portion SO. The first heater HT1 may be disposed at the hyperbolic portions CO, respectively. For example, the first heater HT1 may be disposed at the first hyperbolic portion CO1, the second hyperbolic portion CO2, the third hyperbolic portion CO3, and the fourth hyperbolic portion CO4, respectively. The area of ​​the first heater HT1 may be equal to the area of ​​each of the first hyperbolic portion CO1, the second hyperbolic portion CO2, the third hyperbolic portion CO3, and the fourth hyperbolic portion CO4, but the present disclosure is not limited thereto. The area of ​​the first heater HT1 may be greater than or less than the area of ​​each of the first hyperbolic portion CO1, the second hyperbolic portion CO2, the third hyperbolic portion CO3, and the fourth hyperbolic portion CO4. The second heater HT2 may be disposed at the curved portion SO, respectively. The second heater HT2 may be disposed at a portion of the curved portion SO. For example, the second heater HT2 may be disposed where the first curved portion SO1, the second curved portion SO2, the third curved portion SO3, and the fourth curved portion SO4 intersect with the flat portion FFS. The second heater HT2 may be arranged in a shape completely surrounding the flat portion FFS.

[0171] Then, refer to Figures 13 to 15 , pressing the cover window CW, the display panel 300 and the guide member HG (step S400). For example, the cover window CW may be pressed against the display panel 300 at the front side of the display panel 300, and the guide member HG may be pressed against the display panel 300 at the rear side of the display panel 300.

[0172] When the cover window CW and the guide member HG are pressed above and below the display panel 300, the display panel 300 may be attached to the lower surface of the cover window CW in conformity with the shape of the cover window CW. In this case, the lower surface of the cover window CW may be coated with a pressure sensitive adhesive (PSA), and the upper surface of the display panel 300 and the lower surface of the cover window CW may be attached together by the pressure sensitive adhesive (PSA). As described above, the cover window CW may include a front surface FS, a side surface SS, and a corner portion CS, and the flat display panel 300 may be closely attached to the front surface FS, the side surface SS, and the corner portion CS of the cover window CW.

[0173] When the guide member HG presses the rear side of the display panel 300, the first protective member PRL1 adhered to the lower surface of the display panel 300 may be deformed at the side surface SS and the corner portion CS of the cover window CW having a curvature. For example, when pressed between the cover window CW and the guide member HG, the first protective member PRL1 may be deformed along the shape of the side surface SS of the cover window CW and the corner portion CS thereof. The deformation of the first protective member PRL1 on the corner portion CS may cause the first protective member PRL1 to warp, which may cause wrinkles on the deformed surface of the first protective member PRL1 at the corner portion CS. According to this embodiment, such wrinkles of the first protective member PRL1 can be eliminated by heating the first protective member PRL1 and the display panel 300 using the guide member HG, which will be described later. Heating the first protective member PRL1 may shrink or straighten the wrinkles of the first protective member PRL1, thereby eliminating the wrinkles.

[0174] Subsequently, the display panel 300 and the first protective member PRL1 are heated by the guide member HG (step S500 ). In this step, heat may be applied to the first protective member PRL1 by the heating guide member HG, and thus the first protective member PRL1 contracts.

[0175] In some embodiments, the temperature of the first protective member PRL1 may be increased by applying heat from the heater HT of the guide member HG. The heater HT may apply heat in a temperature range of 50 to 150 degrees Celsius. As described above, the first protective member PRL1 has a shrinkage rate of 20% or more in a temperature range of 50 to 150 degrees Celsius, so that it may shrink as the temperature rises. Because the first protective member PRL1 is coupled to the display panel 300 through a coupling layer, when the first protective member PRL1 shrinks, the display panel 300 coupled thereto also shrinks, and thus the corner portion CS of the display device 10 (i.e., the corner of the cover window CW) may shrink completely.

[0176] Since the side surface SS of the display device 10 adjacent to the corner portion CS is bent downward after the above-mentioned pressing step, the corner portion CS may shrink so that the distance between the molecules of the first protective member PRL1 is reduced. Therefore, the corner portion CS may shrink in the same direction as the center direction between the directions in which the adjacent side surfaces SS of the display device 10 are bent.

[0177] like Fig.15As shown in , during the above-mentioned pressing step, the deformed portion of the first protective member PRL1 may have wrinkles at the corners of the display panel 300. When this occurs, by heating the guide member HG, the display panel 300 contracts together with the first protective member PRL1, so that the strain can be relieved. As discussed above, the deformed surface of the first protective member PRL1 and the wrinkles on the display panel 300 can be relieved or straightened by heating using the guide member HG.

[0178] As described above, the corner portion CS of the display device 10 is shrunk by heating of the guide member HG, and thus the difference between the shape and curvature of the lower surface of the cover window CW disposed on the upper surface of the display panel 300 and the shape and curvature of the upper surface of the display panel 300 can be reduced.

[0179] Then, refer to Fig.16 , remove the guide member HG (step S600). In this step, after the cover window CW and the display panel 300 are attached together, the guide member HG may be removed. In this way, the display device 10 according to the present embodiment may be manufactured.

[0180] Fig.17 is a perspective view showing a guide member according to an embodiment.

[0181] Fig.17 The implementation method and Fig.12 The embodiment of FIG. 4 is different in that the second heater HT2 disposed at the bent portion SO is removed from the guide member HG.

[0182] The side surface SS of the display device 10 has a curvature in one direction so that strain applied to the display panel 300 and the first protective member PRL1 may be minute. By removing the second heater HT2 applying heat to the side surface SS of the display device 10 from the guide member HG, the complicated structure of the guide member HG can be simplified.

[0183] Fig.18 is a graph showing glass transition temperatures of samples of protection members according to the embodiment. Fig.19 : is a graph showing the elastic modulus of the samples of the protection member according to the present embodiment at the glass transition temperature.

[0184] The glass transition temperature and elastic modulus were measured using a dynamic mechanical analyzer (DMA) available from Perkin Elmer Inc. under the conditions of a heating rate of 2° C. / min and a frequency of 2 Hz.

[0185] Fig.18 or Fig.19 The samples of the protective members shown in are as follows:

[0186] Sample 1: MD stretched PET with an elastic modulus of 4.5 GP and a thickness of 75 μm;

[0187] Sample 2: TD stretched PET with an elastic modulus of 4.5 GP and a thickness of 75 μm;

[0188] Sample 3: MD stretched PET with an elastic modulus of 1.6 GP and a thickness of 50 μm;

[0189] Sample 4: TD stretched PET with an elastic modulus of 1.6 GP and a thickness of 50 μm;

[0190] Sample 5: MD stretched PET with an elastic modulus of 3.6 GP and a thickness of 50 μm;

[0191] Sample 6: TD stretched PET with an elastic modulus of 3.6 GP and a thickness of 50 μm,

[0192] Herein, MD (machine direction) elongation refers to elongation in the longitudinal direction of the film, and TD (transverse direction) elongation refers to elongation in the width direction of the film.

[0193] exist Fig.18 In the graph shown in , the horizontal axis represents temperature, and the vertical axis represents tangent δ (tan d) which is a ratio of loss modulus to storage modulus. The glass transition temperature of each sample may be a temperature at a point (or range) where tan δ becomes maximum.

[0194] refer to Fig.18 , the glass transition temperatures of Samples 5 and 6 are in the range of 70 to 80 degrees Celsius, and the glass transition temperatures of Samples 1 to 4 are in the range of 105 to 115 degrees Celsius.

[0195] The protective members according to Samples 1 to 6 exhibit glass transition temperatures in the range of 50 to 150 degrees Celsius, and thus they can be used as protective members of the display device 10 according to an embodiment of the present disclosure. In particular, the protective members according to Samples 3 to 6 exhibit a low elastic modulus of 4 GPa or less, and thus can be applied to the first protective member PRL1 overlapping the display area DA of the display device 10, and the protective members according to Samples 1 and 2 exhibit a high modulus of 4.5 GPa or more, and thus can be applied to the second protective member PRL2 overlapping the bonding area BON of the display device 10.

[0196] refer to Fig.19, Samples 3 and 4 exhibit elastic moduli of 0.6 to 0.9 GPa at a glass transition temperature of approximately 75 degrees Celsius. For example, a single protective member PRL according to this embodiment (see Figure 8 ) may have an elastic modulus of 2.5 GPa or less in the range of the glass transition temperature. Therefore, the protective members according to Samples 3 and 4 exhibit a low elastic modulus of 2.5 GPa or less, and thus may be suitable for use as a protective member PRL overlapping both the display area DA and the bonding area BON of the display device 10.

[0197] Hereinafter, an experimental example of the display device according to the above-described embodiment will be described.

[0198] <Experimental Example: Evaluation of Lighting and Visual Inspection of Joint Areas of Different Protection Members>

[0199] The display device according to the comparative example was manufactured by attaching a PET film having a modulus of 4.5 GPa to a lower surface of the display panel corresponding to each of the display region and the bonding region using acrylic PSA and coupling it to the cover window.

[0200] The display device according to the example is manufactured by attaching a PET film having a modulus of 2.5 GPa to the lower surface of the display panel corresponding to the display area and attaching a PET film having a modulus of 4.5 GPa to the lower surface of the display panel corresponding to the bonding area using acrylic PSA, and connecting them to the cover window.

[0201] The illumination of the display devices according to the comparative example and the example was evaluated, and then a visual inspection was performed after bonding the driver circuit to check for cracks or disconnections in the bonding area. The results are shown in the following Table 1:

[0202] [Table 1]

[0203] Lighting percentage (%) Visual inspection Comparison Examples 100 No cracks or breaks Example 100 No cracks or breaks

[0204] Referring to Table 1, the display panel of the display device according to the example in which a PET film having a low elastic modulus of 2.5 GPa is attached to the lower surface of the display panel corresponding to the display area operates normally like the display panel of the comparative example, and no cracks or disconnections occur at the bonding area.

[0205] From the results, it can be seen that a good display device can be manufactured even by using different protective members having different elastic moduli respectively provided in the display region and the bonding region of the display panel.

[0206] At the end of the detailed description, those skilled in the art will appreciate that many changes and modifications may be made to the preferred embodiment without departing substantially from the principles of the present application. Therefore, the disclosed preferred embodiments of the present application are used only in a general and descriptive sense and not for the purpose of limitation.

Claims

1. A display device, characterized in that The display device defines a display area and includes: a display panel, in the display area; a cover window, disposed on an upper surface of the display panel; and a protective member disposed on a lower surface of the display panel in the display area, Wherein, the material of the protection component is: an elastic modulus of 4 GPa or less at the glass transition temperature of the material, and A shrinkage of 20% or more at the glass transition temperature.

2. The display device according to claim 1, It is characterized in that The display area includes: Flat front surface; a pair of first side surfaces, respectively extending outward from first opposite edges of the flat front surface and curved with a first curvature; a pair of second side surfaces respectively extending outward from second opposite edges of the flat front surface and curved with a second curvature, the first opposite edges being spaced apart from each other in a first direction, and the second opposite edges being spaced apart from each other in a second direction intersecting the first direction; and A plurality of corner portions, each of the corner portions being located in a space between a corresponding one of the pair of first side surfaces and a corresponding one of the pair of second side surfaces and including the first curvature and the second curvature, the corresponding one of the pair of first side surfaces being adjacent to the corresponding one of the pair of second side surfaces.

3. The display device according to claim 2, It is characterized in that The protection member is attached to the lower surface of the display panel corresponding to the flat front surface, the pair of first side surfaces, the pair of second side surfaces, and the plurality of corner portions.

4. The display device according to claim 1, It is characterized in that The glass transition temperature of the protection member is selected from a range of 50 to 150 degrees Celsius.

5. The display device according to claim 1, It is characterized in that At the glass transition temperature selected from the range of 74 to 78 degrees Celsius, the elastic modulus of the protection member corresponds to an elastic modulus selected from the range of 0.6 to 0.9 GPa.

6. A display device, characterized in that The display device defines a display area and a bonding area spaced apart from the display area, and includes: a display panel in the display area and the bonding area; a cover window, arranged on the display panel in the display area; a first protection member disposed below the display panel in the display area; and a second protective member disposed under the display panel in the bonding area and spaced apart from the first protective member, and Wherein, the shrinkage rate of the second protective member is smaller than the shrinkage rate of the first protective member.

7. The display device according to claim 6, It is characterized in that The shrinkage rate of the second protective member is 1% or less at a temperature selected from a temperature range of 50 to 150 degrees Celsius.

8. The display device according to claim 6, It is characterized in that The second protective member has a thermal expansion coefficient of 30 ppm / ° C. or less at a temperature selected from a temperature range of room temperature to 180 degrees Celsius.

9. The display device according to claim 6, It is characterized in that The melting point of the second protective member is equal to or greater than 180 degrees Celsius.

10. The display device according to claim 6, It is characterized in that The elastic modulus of the second protective member is greater than the elastic modulus of the first protective member at a temperature selected from a temperature range of 50 to 150 degrees Celsius.

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