Display device and method of manufacturing same

Abstract

A display device and a method of manufacturing the same are provided in which a portion of a member attached to a cover window is not detached from the cover window when the display device is folded. The display device includes: a display panel including a display element; and a cover window disposed on the display panel and including a window, a first protective layer, and a second protective layer. The window includes a first non-folding region, a second non-folding region, and a foldable region between the first non-folding region and the second non-folding region, and a plurality of grooves are formed in the foldable region. A depth of a trench formed adjacent to the first non-folding region and a depth of a trench formed adjacent to the second non-folding region are greater than a depth of a trench formed in a central region of the foldable region.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2023 - 0193405, filed with the Korean Intellectual Property Office on December 27, 2023, the entire contents of which are incorporated herein by reference. Technical field

[0003] One or more embodiments relate to a display device, and more particularly, to a display device in which a part of a component attached to a cover window does not separate from the cover window when the display device is folded, and a method of manufacturing the display device. Background art

[0004] A display device may be formed by combining various components with each other. Specifically, a display device may be formed by combining a display panel including display elements with a cover window that protects the display panel and combining the cover window with a protective film that protects the cover window.

[0005] A display device may be used as various electronic devices. For example, the display device may be a mobile electronic device such as a smart phone. The electronic device may be a foldable electronic device in which a part of its display surface is folded to increase the area of its display region while reducing its overall size.

[0006] However, when the display device is folded, a part of a component attached to the cover window of such a display device may separate from the cover window. Summary of the invention

[0007] One or more embodiments include a display device in which a part of a component attached to a cover window does not separate from the cover window when the display device is folded, and a method of manufacturing the display device. The embodiments described herein are examples, and the embodiments of the present disclosure are not limited thereto.

[0008] According to one or more embodiments, a display device includes: a display panel including display elements; and a cover window disposed on the display panel, and the cover window includes a window, a first protective layer, and a second protective layer. The window includes a first non - foldable region, a second non - foldable region, and a foldable region located between the first non - foldable region and the second non - foldable region, and a plurality of grooves are formed in the foldable region. The depth of the grooves formed adjacent to the first non - foldable region and the depth of the grooves formed adjacent to the second non - foldable region are greater than the depth of the grooves formed in the central region of the foldable region.

[0009] The window may include a first window surface in a direction facing the display panel and a second window surface in a direction opposite to the direction facing the display panel. The plurality of grooves may include a first groove formed in the first window surface and a second groove formed in the second window surface, and in a plan view, the first groove and the second groove may be alternately arranged.

[0010] The foldable region may include a first foldable region adjacent to the first non-foldable region, a second foldable region adjacent to the second non-foldable region, and a third foldable region located between the first foldable region and the second foldable region. The first groove may include a 1-1 groove formed in the first foldable region, a 2-1 groove formed in the second foldable region, and a 3-1 groove formed in the third foldable region. The depth of the 1-1 groove and the depth of the 2-1 groove may each be greater than the depth of the 3-1 groove.

[0011] The first protective layer may be disposed in the foldable region, and a part of the first protective layer may have an inclined surface.

[0012] The part of the first protective layer disposed in the first foldable region may have a 1-1 inclined surface, and the part of the first protective layer disposed in the second foldable region may have a 2-1 inclined surface.

[0013] The 1-1 groove may include a 1-1-1 groove, a 1-1-2 groove, and a 1-1-3 groove. The 1-1-1 groove may be formed in a part of the first foldable region adjacent to the first non-foldable region, the 1-1-2 groove may be formed in a part of the first foldable region adjacent to the third foldable region, and the 1-1-3 groove may be formed in a part of the first foldable region located between the part of the first foldable region where the 1-1-1 groove is formed and the part of the first foldable region where the 1-1-2 groove is formed. The depth of the 1-1-3 groove may be greater than the depth of the 1-1-2 groove, and the depth of the 1-1-1 groove may be greater than the depth of the 1-1-3 groove.

[0014] The second-1 groove may include a second-1-1 groove, a second-1-2 groove, and a second-1-3 groove. The second-1-1 groove may be formed in a portion of the second foldable region adjacent to the second non-foldable region, the second-1-2 groove may be formed in a portion of the second foldable region adjacent to the third foldable region, and the second-1-3 groove may be formed in a portion of the second foldable region that is between the portion of the second foldable region where the second-1-1 groove is formed and the portion of the second foldable region where the second-1-2 groove is formed. The depth of the second-1-3 groove may be greater than the depth of the second-1-2 groove, and the depth of the second-1-1 groove may be greater than the depth of the second-1-3 groove.

[0015] The display device may further include: a lower adhesive layer disposed between the display panel and the cover window.

[0016] The second groove may include a 1-2 groove formed in the first foldable region, a 2-2 groove formed in the second foldable region, and a 3-2 groove formed in the third foldable region. The depth of the 1-2 groove and the depth of the 2-2 groove may each be greater than the depth of the 3-2 groove.

[0017] The second protective layer may be disposed in the foldable region, and a portion of the second protective layer may have an inclined surface.

[0018] The portion of the second protective layer disposed in the first foldable region may have a 1-2 inclined surface, and the portion of the second protective layer disposed in the second foldable region may have a 2-2 inclined surface.

[0019] The 1-2 groove may include a 1-2-1 groove, a 1-2-2 groove, and a 1-2-3 groove. The 1-2-1 groove may be formed in a portion of the first foldable region adjacent to the first non-foldable region, the 1-2-2 groove may be formed in a portion of the first foldable region adjacent to the third foldable region, and the 1-2-3 groove may be formed in a portion of the first foldable region that is between the portion of the first foldable region where the 1-2-1 groove is formed and the portion of the first foldable region where the 1-2-2 groove is formed. The depth of the 1-2-3 groove may be greater than the depth of the 1-2-2 groove, and the depth of the 1-2-1 groove may be greater than the depth of the 1-2-3 groove.

[0020] The second - 2 groove may include a second - 2 - 1 groove, a second - 2 - 2 groove, and a second - 2 - 3 groove. The second - 2 - 1 groove may be formed in a portion of the second foldable region adjacent to the second non - foldable region, the second - 2 - 2 groove may be formed in a portion of the second foldable region adjacent to the third foldable region, and the second - 2 - 3 groove may be formed in a portion of the second foldable region that is between the portion of the second foldable region where the second - 2 - 1 groove is formed and the portion of the second foldable region where the second - 2 - 2 groove is formed. The depth of the second - 2 - 3 groove may be greater than the depth of the second - 2 - 2 groove, and the depth of the second - 2 - 1 groove may be greater than the depth of the second - 2 - 3 groove.

[0021] The display device may further include: a protective film disposed on the cover window, and an upper adhesive layer disposed between the cover window and the protective film.

[0022] According to one or more embodiments, a method of manufacturing a display device includes: providing a window including a first non - foldable region, a second non - foldable region, and a foldable region located between the first non - foldable region and the second non - foldable region, wherein a plurality of grooves are formed in the foldable region; attaching a release film to the window by using a release film adhesive layer; filling a space with a protective layer composition, wherein the space is surrounded by the release film adhesive layer, the release film, and the portion of the window in which the plurality of grooves are formed; irradiating ultraviolet light onto the protective layer composition; and removing the release film adhesive layer and the release film from the window. The depth of the grooves formed adjacent to the first non - foldable region and the depth of the grooves formed adjacent to the second non - foldable region are greater than the depth of the grooves formed in the central region of the foldable region.

[0023] The window may include a first window surface and a second window surface opposite to the first window surface. The plurality of grooves may include a first groove formed in the first window surface and a second groove formed in the second window surface, and in a plan view, the first groove and the second groove may be alternately arranged.

[0024] The foldable region may include a first foldable region adjacent to the first non - foldable region, a second foldable region adjacent to the second non - foldable region, and a third foldable region located between the first foldable region and the second foldable region. The first groove may include a 1 - 1 groove formed in the first foldable region, a 2 - 1 groove formed in the second foldable region, and a 3 - 1 groove formed in the third foldable region. The depth of the 1 - 1 groove and the depth of the 2 - 1 groove may each be greater than the depth of the 3 - 1 groove.

[0025] The second grooves may include a 1-2 groove formed in the first foldable region, a 2-2 groove formed in the second foldable region, and a 3-2 groove formed in the third foldable region. The depth of the 1-2 groove and the depth of the 2-2 groove may each be greater than the depth of the 3-2 groove.

[0026] The attachment release film may include: a first release film adhesive layer disposed on the first window surface by using the first non-foldable region and the second non-foldable region to attach the first release film to the window; and a second release film adhesive layer disposed on the second window surface by using the first non-foldable region and the second non-foldable region to attach the second release film to the window.

[0027] Filling the space with the protective layer composition may include: filling the first space with a first protective layer composition, wherein the first space is surrounded by the first release film adhesive layer, the first release film, and the portion of the window in which the first groove is formed; and filling the second space with a second protective layer composition, wherein the second space is surrounded by the second release film adhesive layer, the second release film, and the portion of the window in which the second groove is formed.

[0028] Irradiating ultraviolet light may include: forming a first protective layer by irradiating ultraviolet light onto the first protective layer composition; and forming a second protective layer by irradiating ultraviolet light onto the second protective layer composition.

[0029] The portion of the first protective layer disposed in the part of the foldable region adjacent to the first non-foldable region may have a first inclined surface, and the portion of the first protective layer disposed in the part of the foldable region adjacent to the second non-foldable region may have a second inclined surface.

[0030] The portion of the second protective layer disposed in the part of the foldable region adjacent to the first non-foldable region may have a first inclined surface, and the portion of the second protective layer disposed in the part of the foldable region adjacent to the second non-foldable region may have a second inclined surface.

[0031] According to one or more embodiments, a display device includes: a display panel including display elements; and a cover window disposed on the display panel, and the cover window includes a window. The window includes a first window surface in the direction facing the display panel and a second window surface in the direction opposite to the direction facing the display panel, and includes a first non-foldable region, a second non-foldable region, and a foldable region between the first non-foldable region and the second non-foldable region. A plurality of grooves are formed in one of the first window surface and the second window surface, and the depth of the grooves formed adjacent to the first non-foldable region and the depth of the grooves formed adjacent to the second non-foldable region are greater than the depth of the grooves formed in the central region of the foldable region.

[0032] The cover window may further include a first protective layer and a second protective layer. The first protective layer is disposed in the foldable region, the second protective layer is disposed in the foldable region, and a portion of one of the first protective layer and the second protective layer corresponding to the formation of the plurality of grooves may have an inclined surface.

[0033] These and / or other aspects will become apparent and more readily understood from the following description of the embodiments, the drawings, and the claims. Description of the Drawings

[0034] Figure 1 is a schematic perspective view of a display device according to an embodiment.

[0035] Figure 2 is a schematic cross-sectional view of a display device according to an embodiment.

[0036] Figure 3 is taken along Figure 1 line I-I' of Figure 1 a schematic cross-sectional view of the display device.

[0037] Figure 4 is a schematic plan view of a part of a display device according to an embodiment.

[0038] Figure 5 is Figure 3 a schematic enlarged cross-sectional view of region A of the display device of

[0039] Figure 6 is Figure 3 a schematic enlarged cross-sectional view of region A of the display device of

[0040] Figure 7 is a schematic cross-sectional view of a display device according to a comparative example.

[0041] Figure 8 Illustrates the deformation of the lower adhesive layer when the display device according to the comparative example is folded.

[0042] Figure 9 Illustrates the deformation of the lower adhesive layer when the display device according to the embodiment is folded.

[0043] Figure 10 is a schematic cross-sectional view of a part of a display device according to an embodiment.

[0044] Figure 11 is a schematic cross-sectional view of a part of a display device according to an embodiment.

[0045] Figure 12 is a schematic cross-sectional view of a part of a display panel in a display device according to an embodiment.

[0046] Figures 13 to 18 is a schematic cross-sectional view of a process of manufacturing Figure 3 the illustrated display device.

[0047] Figure 19 is a schematic plan view of a part of a display device according to an embodiment.

[0048] Figure 20 is a schematic plan view of a part of a display device according to an embodiment. DETAILED DESCRIPTION

[0049] Now, embodiments will be described in detail with reference to examples illustrated in the drawings, in which the same reference numerals may refer to the same elements throughout. In this regard, the present embodiments may have different forms and should not be construed as limited to the description set forth herein. Accordingly, the embodiments are described below only by referring to the drawings to illustrate aspects of the present description.

[0050] In this specification, it will be understood that when a layer, region, or component is referred to as being "on" another layer, region, or component, it may be directly or indirectly formed on the other layer, region, or component.

[0051] In this specification, when layers, regions, or components are connected to each other, the layers, regions, or components may be directly connected to each other, or another layer, another region, or another component may be interposed between these layers, regions, or components, and thus, these layers, regions, or components may be indirectly connected to each other.

[0052] In this specification, the x-axis, y-axis, and z-axis are not limited to the three axes of a rectangular coordinate system and may be interpreted in a broader sense. For example, the x-axis, y-axis, and z-axis may be perpendicular to each other, or may represent different directions that are not perpendicular to each other.

[0053] In this specification, "in a plan view" means when the target part is observed from above. That is, in this specification, "in a plan view" may mean "when observed from a direction perpendicular to the window W".

[0054] Hereinafter, exemplary embodiments will be described in detail with reference to the drawings, and in the description with reference to the drawings, the same or corresponding components may be denoted by the same reference numerals and redundant descriptions thereof may be omitted.

[0055] Figure 1 is a schematic perspective view of a display device 1 according to an embodiment, and Figure 2 is a schematic cross-sectional view of a display device 1 according to an embodiment. For example, Figure 1 is a perspective view of the display device 1 in an unfolded state, and Figure 2 is a cross-sectional view of the display device 1 in a folded state.

[0056] The display device 1 may have a polygonal shape such as a rectangle. For example, the display device 1 has a rectangular shape in which its horizontal length is greater than its vertical length, a rectangular shape in which its horizontal length is less than its vertical length, or a square shape. In some embodiments, the display device 1 has various other shapes such as an oval shape or a circular shape. Although Figure 1 the display device 1 is shown having a rectangular shape in which the horizontal length is greater than the vertical length, the embodiments of the present disclosure are not necessarily limited thereto.

[0057] The display device 1 has a first surface S1 and a second surface S2 opposite to the first surface S1. In an embodiment, the first surface S1 is the lower surface (in the -z direction) of the display device 1, and the second surface S2 is the upper surface (in the +z direction) of the display device 1. The display device 1 displays an image on the second surface S2. For example, the second surface S2 includes a display surface. In some embodiments, the display device 1 also displays an image on the first surface S1.

[0058] The display device 1 can be folded. For example, at least a part of the display device 1 is flexible, and when the flexible part is bent, the display device 1 can be folded. Accordingly, the display device 1 includes a foldable area and a non-foldable area on at least one side of the foldable area. In this specification, "non-folded" means not folded, which includes not only the case where it is non-flexible and difficult to fold, but also the case where it is flexible but not folded. The display device 1 can display an image not only in the non-foldable area but also in the foldable area.

[0059] As Figure 1 shown, the display device 1 includes a first non-foldable area NFA1, a second non-foldable area NFA2, and a foldable area FA. The first non-foldable area NFA1 and the second non-foldable area NFA2 are non-foldable areas, and the foldable area FA is a foldable flexible area.

[0060] The foldable area FA extends in a direction crossing a virtual straight line connecting the first non-foldable area NFA1 and the second non-foldable area NFA2. For example, when the display device 1 is in an unfolded state, the first non-foldable area NFA1 and the second non-foldable area NFA2 are spaced apart from each other in a first direction such as the x-axis direction. The foldable area FA is located between the first non-foldable area NFA1 and the second non-foldable area NFA2. For example, the first non-foldable area NFA1 is adjacent to one side of the foldable area FA, and the second non-foldable area NFA2 is adjacent to the other side of the foldable area FA. When the display device 1 is in an unfolded state, the foldable area FA extends in a second direction such as the y-axis direction crossing the first direction such as the x-axis direction.

[0061] The folding line FL may be defined in the foldable region FA that extends in a second direction such as the y-axis direction, which is the extending direction of the foldable region FA. Accordingly, the display device 1 may be folded in the foldable region FA. The foldable region FA and the folding line FL of the foldable region FA overlap with the region where the image of the display device 1 is displayed. When the display device 1 is folded, the part where the image is displayed is folded.

[0062] For ease of description, although Figure 1 it is shown that the first non-foldable region NFA1 and the second non-foldable region NFA2 have the same or similar areas and the display device 1 includes one foldable region FA, the embodiments of the present disclosure are not necessarily limited thereto. For example, in other embodiments, the first non-foldable region NFA1 and the second non-foldable region NFA2 have different areas. In other embodiments, the display device 1 includes a plurality of foldable regions FA. For example, the plurality of non-foldable regions are spaced apart from each other, and each of the plurality of foldable regions FA is disposed between the non-foldable regions. Each foldable region FA may be folded with respect to the folding line FL, and a plurality of folding lines FL are provided.

[0063] Although Figure 1 it is shown that the folding line FL passes through the center of the foldable region FA and the foldable region FA is symmetric with respect to the folding line FL, the embodiments of the present disclosure are not necessarily limited thereto. In some embodiments, the folding line FL is asymmetrically located in the foldable region FA.

[0064] As Figure 2 shown, the display device 1 may be folded such that the second surface S2 of the first non-foldable region NFA1 faces the second surface S2 of the second non-foldable region NFA2. For example, when the foldable region FA of the display device 1 is bent, the second surface S2 of the first non-foldable region NFA1 and the second surface S2 of the second non-foldable region NFA2 face each other. Even when the display device 1 is folded, the foldable region FA extends in a direction intersecting the virtual straight line connecting the first non-foldable region NFA1 and the second non-foldable region NFA2. For example, when the display device 1 is folded, the foldable region FA extends in a second direction (such as the y-axis direction) intersecting the virtual straight line (such as a straight line parallel to the z-axis direction) connecting the first non-foldable region NFA1 and the second non-foldable region NFA2. The foldable region FA may be folded and then unfolded. For example, the display device 1 is a foldable display device.

[0065] In this specification, the term "folding" means that the shape is not fixed but changes from the original shape to a different shape, and includes being folded, bent, or bent along at least one specific line such as the folding line FL. Accordingly, although Figure 2Shows a state in which the second surface S2 of the first non-folded area NFA1 and the second surface S2 of the second non-folded area NFA2 are folded to be parallel to each other and face each other, but embodiments of the present disclosure are not necessarily limited thereto. For example, the second surface S2 of the first non-folded area NFA1 and the second surface S2 of the second non-folded area NFA2 may be folded to form a preset angle such as an acute angle, a right angle, or an obtuse angle, with the foldable area FA therebetween.

[0066] In addition, although Figure 2 shows the display device 1 being folded inward such that a part of the second surface S2 and another part of the second surface S2 face each other, embodiments of the present disclosure are not necessarily limited thereto. For example, the display device 1 may be folded outward such that a part of the first surface S1 and another part of the first surface S1 face each other. For example, when a part of the display surface is folded to face each other, the display device 1 is in an inward-folded state, or when the display surface is folded to be exposed outward, the display device 1 is in an outward-folded state. Hereinafter, for convenience of description, the description will focus on the case where the display device 1 is in an inward-folded state.

[0067] Figure 3 is a schematic cross-sectional view of the display device 1 taken along Figure 1 line I-I'. Figure 1 Figure 4 is a schematic plan view of a part of the display device 1 according to an embodiment. For convenience, Figure 4 shows a plan view of the window W. For ease of illustration, Figure 4 the second groove T2 is shown together.

[0068] As Figure 3 shown, in an embodiment, the display device 1 includes a display panel 10, a cover window CW, and a protective film PF. The display panel 10 displays an image. For example, the display panel 10 includes a plurality of display elements, and the plurality of display elements emit light. Accordingly, the display panel 10 displays an image by the light emitted from the plurality of display elements. In an embodiment, each of the display elements is an organic light-emitting diode including an organic emission layer. In an embodiment, the display element is a light-emitting diode. The size of the light-emitting diode is at the micro level or the nano level. For example, the light-emitting diode is a micro light-emitting diode. In some embodiments, the light-emitting diode is a nanorod light-emitting diode. The nanorod light-emitting diode includes gallium nitride (GaN). In an embodiment, a color conversion layer is provided on the nanorod light-emitting diode. The color conversion layer includes quantum dots. In an embodiment, the display element is a quantum dot light-emitting diode including a quantum dot emission layer. In an embodiment, the display element is an inorganic light-emitting diode including an inorganic semiconductor. A detailed description of the components included in the display panel 10 is provided below.

[0069] ​The cover window CW is disposed on the display panel 10. The cover window CW covers the upper surface (in the +z direction) of the display panel 10. The cover window CW protects the upper surface (in the +z direction) of the display panel 10. The cover window CW has a high transmittance for transmitting light emitted from the display panel 10 and has a small thickness for reducing the weight of the display device 1. In addition, the cover window CW has a high strength and high hardness for protecting the display panel 10 from external impacts. The lower adhesive layer LAL is disposed between the display panel 10 and the cover window CW. The cover window CW is attached to the display panel 10 through the lower adhesive layer LAL. The lower adhesive layer LAL includes an adhesive member such as an optically clear adhesive (OCA) or a pressure sensitive adhesive (PSA).

[0070] The cover window CW includes a window W, a first protective layer R1, and a second protective layer R2. The window W is disposed in each of a first non-foldable region NFA1, a second non-foldable region NFA2, and a foldable region FA, and the first protective layer R1 and the second protective layer R2 are disposed in the foldable region FA. The window W is flexible. The window W protects the display panel 10 by being easily bent in response to an external force without causing cracks or the like. The window W may include glass or plastic. In an embodiment, the window W includes ultra-thin glass (UTG) that has been strengthened by chemical strengthening or thermal strengthening. In an embodiment, the window W includes a polymer resin. As described above, the display device 1 includes a first non-foldable region NFA1, a second non-foldable region NFA2, and a foldable region FA. Since the display device 1 includes the cover window CW and the cover window CW includes the window W, the window W includes the first non-foldable region NFA1 and the second non-foldable region NFA2 and the foldable region FA as described above. Hereinafter, for convenience, the window W will be described as including the first non-foldable region NFA1, the second non-foldable region NFA2, and the foldable region FA.

[0071] The window W includes a first window surface WS1 and a second window surface WS2. The first window surface WS1 corresponds to the first surface S1 of the display device 1, and the second window surface WS2 corresponds to the second surface S2 of the display device 1. For example, the first window surface WS1 of the window W faces the same direction (such as the -z direction) as the first surface S1 of the display device 1, and the second window surface WS2 of the window W faces the same direction (such as the +z direction) as the second surface S2 of the display device 1. For example, the second window surface WS2 is opposite to the first window surface WS1. For example, the first window surface WS1 faces the display panel 10, and the second window surface WS2 faces the direction opposite to the direction facing the display panel 10.

[0072] For example, when the window W is in an expanded state, the first non-foldable region NFA1 and the second non-foldable region NFA2 are spaced apart from each other in a first direction, such as the x-axis direction, which intersects a second direction, such as the y-axis direction. The foldable region FA is located between the first non-foldable region NFA1 and the second non-foldable region NFA2 and extends in a second direction, such as the y-axis direction, which intersects a virtual straight line connecting the first non-foldable region NFA1 to the second non-foldable region NFA2.

[0073] The fold line FL is defined in the foldable region FA and extends in a second direction, such as the y-axis direction, which is the extension direction of the foldable region FA. Accordingly, the window W can be folded in the foldable region FA. The window W can be folded such that the second window surface WS2 of the first non-foldable region NFA1 and the second window surface WS2 of the second non-foldable region NFA2 face each other based on the fold line FL. For example, when the foldable region FA of the window W is bent, the second window surface WS2 of the first non-foldable region NFA1 and the second window surface WS2 of the second non-foldable region NFA2 come together to face each other.

[0074] A plurality of grooves T are formed in the foldable region FA of the window W. For example, the window W includes a plurality of grooves T, and the plurality of grooves T are formed in the foldable region FA. The number of grooves T formed in the foldable region FA of the window W can be changed in various ways. The plurality of grooves T are alternately located on both sides of the window W. For example, a part of the plurality of grooves T is formed in the first window surface WS1, and another part of the plurality of grooves T is formed in the second window surface WS2. For example, as Figure 4 shown, the plurality of grooves T include a first groove T1 and a second groove T2. The first groove T1 is formed in the first window surface WS1, and the second groove T2 is formed in the second window surface WS2.

[0075] Each of the grooves T is a region where a part of the window W has been removed. For example, forming a groove T in one surface of the window W includes: removing a part of the window W from one surface of the window W in the thickness direction of the window W such that only a part of the window W adjacent to the other surface of the window W is retained. For example, each of the first grooves T1 is formed at a position where a part of the window W has been removed from the first window surface WS1 in a third direction, such as the z-axis direction. A part of the window W adjacent to the second window surface WS2 corresponding to the first groove T1 is retained. Each of the second grooves T2 is formed at a position where a part of the window W has been removed from the second window surface WS2 in a third direction, such as the z-axis direction. A part of the window W adjacent to the first window surface WS1 corresponding to the second groove T2 is retained.

[0076] In a plan view, the grooves T formed in the first window surface WS1 and the grooves T formed in the second window surface WS2 are alternately arranged. For example, as Figure 4 shown, the first groove T1 and the second groove T2 are alternately arranged in a plan view. When a plurality of grooves T are formed in the foldable region FA of the window W, the folding operation of the window W becomes easier.

[0077] Each of the first groove T1 and the second groove T2 extends in a second direction, such as the y-axis direction, which intersects a first direction, such as the x-axis direction. The longitudinal direction of each of the first groove T1 and the second groove T2 is the second direction, such as the y-axis direction. In an embodiment, as Figure 4 shown, the length of each of the first groove T1 and the second groove T2 in the second direction, such as the y-axis direction, is equal to the width of the window W in the second direction, such as the y-axis direction. In an embodiment, the length of each of the first groove T1 and the second groove T2 in the second direction, such as the y-axis direction, is different from the width of the window W in the second direction, such as the y-axis direction. In an embodiment, the depth of each of the first groove T1 and the second groove T2 in a third direction, such as the z-axis direction, is less than the thickness of the window W in the third direction, such as the z-axis direction. The depth direction of each of the first groove T1 and the second groove T2 is the third direction, such as the z-axis direction. A detailed description of the depth of each of the first groove T1 and the second groove T2 is provided below.

[0078] A first protective layer R1 is provided in the foldable region FA. For example, the first protective layer R1 is provided on the first window surface WS1 in the foldable region FA. Additionally, the first protective layer R1 fills the first groove T1 formed in the first window surface WS1. The first protective layer R1 includes an optically transparent material having low physical strength and hardness. The first protective layer R1 includes a flexible material. Accordingly, the first protective layer R1 can be stretched or compressed by an external force. For example, the first protective layer R1 includes at least one of a silicone-based resin, an optically transparent resin (OCR), and an OCA. The modulus of the first protective layer R1 is less than the modulus of the window W. The first protective layer R1 has a refractive index substantially the same as the refractive index of the window W.

[0079] The second protective layer R2 is disposed in the foldable region FA. For example, the second protective layer R2 is disposed on the second window surface WS2 in the foldable region FA. Additionally, the second protective layer R2 fills the second trench T2 formed in the second window surface WS2. The second protective layer R2 includes a material that is the same as or substantially similar to that of the first protective layer R1. For example, the second protective layer R2 includes an optically transparent material having low physical strength and hardness. The second protective layer R2 includes a flexible material. Accordingly, the second protective layer R2 can be stretched or compressed by an external force. For example, the second protective layer R2 includes at least one of a silicone resin, an OCR, and an OCA. The modulus of the second protective layer R2 is less than that of the window W. The second protective layer R2 has a refractive index that is substantially the same as that of the window W.

[0080] The protective film PF is disposed on the cover window CW. The protective film PF protects the cover window CW and prevents or reduces scratches on the upper surface (in the +z direction) of the cover window CW. In an embodiment, the protective film PF includes a polymer resin. In an embodiment, the protective film PF includes an inorganic material. The upper adhesive layer UAL is disposed between the cover window CW and the protective film PF. The protective film PF is attached to the cover window CW through the upper adhesive layer UAL. The upper adhesive layer UAL includes an adhesive member such as an OCA or a PSA.

[0081] Figure 5 is Figure 3 A schematic enlarged cross-sectional view of the region A of the display device 1. Figure 6 is Figure 3 A schematic enlarged cross-sectional view of the region A of the display device 1. As Figure 5 and Figure 6 shown, the depth of each trench T can vary depending on its position in the foldable region FA.

[0082] For example, as Figure 5 shown, the foldable region FA includes a first foldable region FA1, a second foldable region FA2, and a third foldable region FA3. The first foldable region FA1 is adjacent to the first non-foldable region NFA1, and the second foldable region FA2 is adjacent to the second non-foldable region NFA2. The third foldable region FA3 is located between the first foldable region FA1 and the second foldable region FA2. For example, the third foldable region FA3 includes the central region of the foldable region FA. The central region of the foldable region FA includes the center of the foldable region FA.

[0083] As described above, the first non-foldable region NFA1 and the second non-foldable region NFA2 are spaced apart from each other in a first direction such as the x-axis direction. The first non-foldable region NFA1 is adjacent to one side of the foldable region FA, and the second non-foldable region NFA2 is adjacent to the other side of the foldable region FA. For example, the distance in the first direction such as the x-axis direction between one end of the foldable region FA in contact with the first non-foldable region NFA1 and the center of the foldable region FA is equal to the distance in the first direction such as the x-axis direction between the other end of the foldable region FA in contact with the second non-foldable region NFA2 and the center of the foldable region FA. For example, the center of the foldable region FA is the portion of the foldable region FA where the distance from the first non-foldable region NFA1 in the first direction such as the x-axis direction is equal to the distance from the second non-foldable region NFA2 in the first direction such as the x-axis direction. For example, the center of the foldable region FA is the portion of the foldable region FA that is positioned farthest from the first non-foldable region NFA1 and the second non-foldable region NFA2 in the first direction such as the x-axis direction.

[0084] As described above, the plurality of grooves T include a first groove T1 and a second groove T2. The first groove T1 includes a 1-1 groove T11, a 2-1 groove T21, and a 3-1 groove T31. The 1-1 groove T11 is formed in the first foldable region FA1, the 2-1 groove T21 is formed in the second foldable region FA2, and the 3-1 groove T31 is formed in the third foldable region FA3. For example, the 1-1 groove T11 is formed in the first window surface WS1 of the first foldable region FA1, the 2-1 groove T21 is formed in the first window surface WS1 of the second foldable region FA2, and the 3-1 groove T31 is formed in the first window surface WS1 of the third foldable region FA3.

[0085] Similarly, the second groove T2 includes a 1-2 groove T12, a 2-2 groove T22, and a 3-2 groove T32. The 1-2 groove T12 is formed in the first foldable region FA1, the 2-2 groove T22 is formed in the second foldable region FA2, and the 3-2 groove T32 is formed in the third foldable region FA3. For example, the 1-2 groove T12 is formed in the second window surface WS2 of the first foldable region FA1, the 2-2 groove T22 is formed in the second window surface WS2 of the second foldable region FA2, and the 3-2 groove T32 is formed in the second window surface WS2 of the third foldable region FA3.

[0086] As Figure 5As shown, the depth of the trench T adjacent to the first non-foldable region NFA1 is greater than the depth of the trench T in the central region of the foldable region FA. For example, the depth of the first trench T1 in the first foldable region FA1 is greater than the depth of the first trench T1 in the third foldable region FA3. For example, the 1-1 trench T11 has a 1-1 depth d11, and the 3-1 trench T31 has a 3-1 depth d31. The 1-1 depth d11 is greater than the 3-1 depth d31.

[0087] The depth of the trench T adjacent to the second non-foldable region NFA2 is greater than the depth of the trench T formed in the central region of the foldable region FA. For example, the depth of the first trench T1 in the second foldable region FA2 is greater than the depth of the first trench T1 in the third foldable region FA3. For example, the 2-1 trench T21 has a 2-1 depth d21, and the 2-1 depth d21 is greater than the 3-1 depth d31.

[0088] In this specification, the depth of the first trench T1 refers to the shortest distance between the bottom surface of the first trench T1 and a virtual extension surface parallel to the first window surface WS1. For example, the 1-1 depth d11 refers to the shortest distance between the bottom surface of the 1-1 trench T11 and a virtual extension surface parallel to the first window surface WS1, the 2-1 depth d21 refers to the shortest distance between the bottom surface of the 2-1 trench T21 and a virtual extension surface parallel to the first window surface WS1, and the 3-1 depth d31 refers to the shortest distance between the bottom surface of the 3-1 trench T31 and a virtual extension surface parallel to the first window surface WS1.

[0089] However, in this specification, the depth of the first trench T1 also refers to the shortest distance between the first window surface WS1 and the bottom surface of the first trench T1 in the thickness direction of the window W, such as the z-axis direction. For example, the 1-1 depth d11 refers to the shortest distance between the first window surface WS1 and the bottom surface of the 1-1 trench T11 in the thickness direction of the window W, such as the z-axis direction, the 2-1 depth d21 refers to the shortest distance between the first window surface WS1 and the bottom surface of the 2-1 trench T21 in the thickness direction of the window W, such as the z-axis direction, and the 3-1 depth d31 refers to the shortest distance between the first window surface WS1 and the bottom surface of the 3-1 trench T31 in the thickness direction of the window W, such as the z-axis direction.

[0090] Similarly, as Figure 6As shown, the depth of the second groove T2 formed in the first foldable region FA1 is greater than the depth of the second groove T2 formed in the third foldable region FA3. For example, the 1-2 groove T12 has a 1-2 depth d12, and the 3-2 groove T32 has a 3-2 depth d32. The 1-2 depth d12 is greater than the 3-2 depth d32. The depth of the second groove T2 formed in the second foldable region FA2 is greater than the depth of the second groove T2 formed in the third foldable region FA3. For example, the 2-2 groove T22 has a 2-2 depth d22, and the 2-2 depth d22 is greater than the 3-2 depth d32.

[0091] In this specification, the depth of the second groove T2 refers to the shortest distance between the bottom surface of the second groove T2 and a virtual extension surface parallel to the second window surface WS2. For example, the 1-2 depth d12 refers to the shortest distance between the bottom surface of the 1-2 groove T12 and a virtual extension surface parallel to the second window surface WS2, the 2-2 depth d22 refers to the shortest distance between the bottom surface of the 2-2 groove T22 and a virtual extension surface parallel to the second window surface WS2, and the 3-2 depth d32 refers to the shortest distance between the bottom surface of the 3-2 groove T32 and a virtual extension surface parallel to the second window surface WS2.

[0092] However, in this specification, the depth of the second groove T2 also refers to the shortest distance between the second window surface WS2 and the bottom surface of the second groove T2 in the thickness direction of the window W, such as the z-axis direction. For example, the 1-2 depth d12 refers to the shortest distance between the second window surface WS2 and the bottom surface of the 1-2 groove T12 in the thickness direction of the window W, such as the z-axis direction, the 2-2 depth d22 refers to the shortest distance between the second window surface WS2 and the bottom surface of the 2-2 groove T22 in the thickness direction of the window W, such as the z-axis direction, and the 3-2 depth d32 refers to the shortest distance between the second window surface WS2 and the bottom surface of the 3-2 groove T32 in the thickness direction of the window W, such as the z-axis direction.

[0093] As described above, the first protective layer R1 is disposed on the first window surface WS1 of the foldable region FA and fills the first groove T1 formed in the first window surface WS1. A part of the first protective layer R1 has an inclined surface such as an inclined surface. For example, the part of the first protective layer R1 adjacent to the first non-foldable region NFA1 has an inclined surface, and the part of the first protective layer R1 adjacent to the second non-foldable region NFA2 has an inclined surface. For example, the part of the first protective layer R1 disposed in the first foldable region FA1 has a 1-1 inclined surface SL11, and the part of the first protective layer R1 disposed in the second foldable region FA2 has a 2-1 inclined surface SL21.

[0094] The first inclined surface SL11 of the first - 1 is inclined with respect to a virtual extended surface parallel to the first window surface WS1 of the first non - folding region NFA1 of the window W, and the first inclined surface SL12 of the first - 2 is inclined with respect to a virtual extended surface parallel to the first window surface WS1 of the second non - folding region NFA2 of the window W. For example, the angle at which the first inclined surface SL11 of the first - 1 is inclined with respect to the virtual extended surface parallel to the first window surface WS1 of the first non - folding region NFA1 is the first - 1 angle θ11. The first - 1 angle θ11 is greater than 0° and less than 90°. The angle at which the second inclined surface SL21 of the second - 1 is inclined with respect to the virtual extended surface parallel to the first window surface WS1 of the second non - folding region NFA2 is the second - 1 angle θ21. The second - 1 angle θ21 is greater than 0° and less than 90°. For example, each of the first - 1 angle θ11 and the second - 1 angle θ21 is an acute angle. For example, the first protective layer R1 has a forward - facing tapered inclined surface.

[0095] As described above, the second protective layer R2 is disposed on the second window surface WS2 of the foldable region FA and fills the second groove T2 formed in the second window surface WS2. Similarly, as Figure 6 shown, a part of the second protective layer R2 has an inclined surface. For example, the part of the second protective layer R2 adjacent to the first non - folding region NFA1 has an inclined surface, and the part of the second protective layer R2 adjacent to the second non - folding region NFA2 has an inclined surface. For example, the part of the second protective layer R2 disposed in the first foldable region FA1 has the first - 2 inclined surface SL12, and the part of the second protective layer R2 disposed in the second foldable region FA2 has the second - 2 inclined surface SL22.

[0096] The first inclined surface SL12 of the first - 2 is inclined with respect to a virtual extended surface parallel to the second window surface WS2 of the first non - folding region NFA1 of the window W, and the second inclined surface SL22 of the second - 2 is inclined with respect to a virtual extended surface parallel to the second window surface WS2 of the second non - folding region NFA2 of the window W. For example, the angle at which the first inclined surface SL12 of the first - 2 is inclined with respect to the virtual extended surface parallel to the second window surface WS2 of the first non - folding region NFA1 is the first - 2 angle θ12. The first - 2 angle θ12 is greater than 0° and less than 90°. The angle at which the second inclined surface SL22 of the second - 2 is inclined with respect to the virtual extended surface parallel to the second window surface WS2 of the second non - folding region NFA2 is the second - 2 angle θ22. The second - 2 angle θ22 is greater than 0° and less than 90°. For example, each of the first - 2 angle θ12 and the second - 2 angle θ22 is an acute angle. For example, the first protective layer R2 has a forward - facing tapered inclined surface.

[0097] Figure 7It is a schematic cross-sectional view of the display device according to the comparative example. Since the display device according to the comparative example is similar to the display device 1 according to the embodiment, the following description will focus on the differences from the display device 1 according to the embodiment.

[0098] As Figure 7 shown, for the display device according to the comparative example, a plurality of grooves T are formed in the foldable area FA of the window W. The plurality of grooves T include a first groove T1 and a second groove T2. The first groove T1 is formed in the first window surface WS1, and the second groove T2 is formed in the second window surface WS2. A first protective layer R1 is provided on the first window surface WS1 of the foldable area FA and fills the first groove T1 formed in the first window surface WS1. A second protective layer R2 is provided on the second window surface WS2 of the foldable area FA and fills the second groove T2 formed in the second window surface WS2.

[0099] The first groove T1 includes a 1-1 groove T11, a 2-1 groove T21, and a 3-1 groove T31. For example, the 1-1 groove T11 is formed in the first window surface WS1 of the first foldable area FA1, the 2-1 groove T21 is formed in the first window surface WS1 of the second foldable area FA2, and the 3-1 groove T31 is formed in the first window surface WS1 of the third foldable area FA3. The second groove T2 includes a 1-2 groove T12, a 2-2 groove T22, and a 3-2 groove T32. For example, the 1-2 groove T12 is formed in the second window surface WS2 of the first foldable area FA1, the 2-2 groove T22 is formed in the second window surface WS2 of the second foldable area FA2, and the 3-2 groove T32 is formed in the second window surface WS2 of the third foldable area FA3.

[0100] However, for the display device according to the comparative example, the depth of the first-1 groove T11 and the depth of the second-1 groove T21 are each the same as or substantially similar to the depth de1 of the third-1 groove T31. Similarly, the depth of the first-2 groove T12 and the depth of the second-2 groove T22 are each the same as or substantially similar to the depth de2 of the third-2 groove T32. For example, one end of the first protective layer R1 adjacent to the first non-folded area NFA1 and a virtual extension surface parallel to the first window surface WS1 of the first non-folded area NFA1 form a first-1 comparison angle θ11'. The other end of the first protective layer R1 adjacent to the second non-folded area NFA2 and a virtual extension surface parallel to the first window surface WS1 of the second non-folded area NFA2 form a second-1 comparison angle θ21'. Each of the first-1 comparison angle θ11' and the second-1 comparison angle θ21' is approximately 90°. Similarly, one end of the second protective layer R2 adjacent to the first non-folded area NFA1 and a virtual extension surface parallel to the second window surface WS2 of the first non-folded area NFA1 form a first-2 comparison angle θ12'. The other end of the second protective layer R2 adjacent to the second non-folded area NFA2 and a virtual extension surface parallel to the second window surface WS2 of the second non-folded area NFA2 form a second-2 comparison angle θ22'. Each of the first-2 comparison angle θ12' and the second-2 comparison angle θ22' is approximately 90°.

[0101] Figure 8 Illustrated is the deformation of the lower adhesive layer LAL when the display device according to the comparative example is folded. As Figure 8 shown, when the display device according to the comparative example is folded, the thickness of a part of the lower adhesive layer LAL attached to the first window surface WS1 of the window W is reduced. For example, when folding the display device, tensile stress is applied to the lower adhesive layer LAL. Accordingly, the thickness of the part of the lower adhesive layer LAL disposed adjacent to the part where the first protective layer R1 has a step is reduced. Accordingly, the adhesive strength of the part of the lower adhesive layer LAL having a reduced thickness is lowered, and thus, a part of a component such as the display panel 10 attached to the cover window CW through the lower adhesive layer LAL may be detached from the cover window CW.

[0102] However, for the display device 1 according to the present embodiment, the first protective layer R1 has an inclined surface. Accordingly, when the display device 1 is folded inward, even when tensile stress is applied to the lower adhesive layer LAL, the lower adhesive layer LAL moves along the inclined surface of the first protective layer R1. Accordingly, as illustrated is the deformation of the lower adhesive layer LAL when folding the display device 1 according to the embodiment Figure 9As shown, the thickness of a part of the lower adhesive layer LAL is not reduced, and the lower adhesive layer LAL has a uniform thickness as a whole. For example, the adhesive strength of this part of the lower adhesive layer LAL is not reduced, and a part of a component such as the display panel 10 attached to the cover window CW through the lower adhesive layer LAL does not detach from the cover window CW. For example, when the display device 1 is folded inward, a part of a component such as the display panel 10 attached to the cover window CW does not detach from the cover window CW.

[0103] In addition, for the display device 1 according to the present embodiment, the second protective layer R2 also has an inclined surface. Accordingly, even when the display device 1 is in an outwardly folded state in which the display surface is exposed outward, the upper adhesive layer UAL moves along the inclined surface of the second protective layer R2. Accordingly, the thickness of a part of the upper adhesive layer UAL is not reduced, and the upper adhesive layer UAL has a uniform thickness as a whole. For example, the adhesive strength of a part of the upper adhesive layer UAL is not reduced, and a part of a component such as the protective film PF attached to the cover window CW through the upper adhesive layer UAL does not detach from the cover window CW. For example, when the display device 1 is folded outward, a part of a component such as the protective film PF attached to the cover window CW does not detach from the cover window CW.

[0104] Although Figure 5 and Figure 6 it is shown that there is one first groove T11, one second groove T12, one third groove T21, and one fourth groove T22, the embodiments of the present disclosure are not necessarily limited thereto. For example, a plurality of each of the first groove T11, the second groove T12, the third groove T21, and the fourth groove T22 may be provided.

[0105] Figure 10 is a schematic cross-sectional view of a part of the display device 1 according to the embodiment. Figure 11 is a schematic cross-sectional view of a part of the display device 1 according to the embodiment.

[0106] As Figure 10As shown, in the embodiment, the first trench T11 includes a first sub-trench T111, a first sub-trench T112, and a first sub-trench T113. The first sub-trench T111 is formed in a portion of the first foldable region FA1 adjacent to the first non-foldable region NFA1, and the first sub-trench T112 is formed in a portion of the first foldable region FA1 adjacent to the third foldable region FA3. The first sub-trench T113 is formed in a portion of the first foldable region FA1 between the portion of the first foldable region FA1 where the first sub-trench T111 is formed and the portion of the first foldable region FA1 where the first sub-trench T112 is formed. For example, in a plan view, the first sub-trench T111 is formed adjacent to the first non-foldable region NFA1, the first sub-trench T112 is formed adjacent to the third foldable region FA3, and the first sub-trench T113 is formed between the first sub-trench T111 and the first sub-trench T112.

[0107] The second trench T21 includes a second sub-trench T211, a second sub-trench T212, and a second sub-trench T213. The second sub-trench T211 is formed in a portion of the second foldable region FA2 adjacent to the second non-foldable region NFA2, and the second sub-trench T212 is formed in a portion of the second foldable region FA2 adjacent to the third foldable region FA3. The second sub-trench T213 is formed in a portion of the second foldable region FA2 between the portion of the second foldable region FA2 where the second sub-trench T211 is formed and the portion of the second foldable region FA2 where the second sub-trench T212 is formed. For example, in a plan view, the second sub-trench T211 is formed adjacent to the second non-foldable region NFA2, the second sub-trench T212 is formed adjacent to the third foldable region FA3, and the second sub-trench T213 is formed between the second sub-trench T211 and the second sub-trench T212.

[0108] The first-first-first groove T111 has a first-first-first depth d111, the first-first-second groove T112 has a first-first-second depth d112, and the first-first-third groove T113 has a first-first-third depth d113. The first-first-third depth d113 is greater than the first-first-second depth d112, and the first-first-first depth d111 is greater than the first-first-third depth d113. Additionally, the first-first-second depth d112 is greater than the third-first depth d31. The second-first-first groove T211 has a second-first-first depth d211, the second-first-second groove T212 has a second-first-second depth d212, and the second-first-third groove T213 has a second-first-third depth d213. The second-first-third depth d213 is greater than the second-first-second depth d212, and the second-first-first depth d211 is greater than the second-first-third depth d213.

[0109] For example, the depth of the first-first groove T11 increases from the third foldable region FA3 towards the first non-foldable region NFA1, and the depth of the second-first groove T21 increases from the third foldable region FA3 towards the second non-foldable region NFA2. For example, the depth of the first-first groove T11 decreases from the first non-foldable region NFA1 towards the third foldable region FA3, and the depth of the second-first groove T21 decreases from the second non-foldable region NFA2 towards the third foldable region FA3. Additionally, the first-first angle θ11 of the first-first slope SL11 is further decreased, and the second-first angle θ21 of the second-first slope SL21 is further decreased. Accordingly, the lower adhesive layer LAL can move more easily along the slope of the first protective layer R1. For example, when the display device 1 is folded, a part of a component such as the display panel 10 attached to the cover window CW does not detach from the cover window CW.

[0110] As Figure 11As shown, in the embodiment, the first to second trenches T12 include the first to second sub-trenches T121, T122, and T123. The first to second sub-trench T121 is formed in a portion of the first foldable region FA1 adjacent to the first non-foldable region NFA1, and the first to second sub-trench T122 is formed in a portion of the first foldable region FA1 adjacent to the third foldable region FA3. The first to second sub-trench T123 is formed in a portion of the first foldable region FA1 between the portion of the first foldable region FA1 where the first to second sub-trench T121 is formed and the portion of the first foldable region FA1 where the first to second sub-trench T122 is formed. For example, in a plan view, the first to second sub-trench T121 is formed adjacent to the first non-foldable region NFA1, the first to second sub-trench T122 is formed adjacent to the third foldable region FA3, and the first to second sub-trench T123 is formed between the first to second sub-trench T121 and the first to second sub-trench T122.

[0111] The second to second trench T22 includes the second to second sub-trenches T221, T222, and T223. The second to second sub-trench T221 is formed in a portion of the second foldable region FA2 adjacent to the second non-foldable region NFA2, and the second to second sub-trench T222 is formed in a portion of the second foldable region FA2 adjacent to the third foldable region FA3. The second to second sub-trench T223 is formed in a portion of the second foldable region FA2 between the portion of the second foldable region FA2 where the second to second sub-trench T221 is formed and the portion of the second foldable region FA2 where the second to second sub-trench T222 is formed. For example, in a plan view, the second to second sub-trench T221 is formed adjacent to the second non-foldable region NFA2, the second to second sub-trench T222 is formed adjacent to the third foldable region FA3, and the second to second sub-trench T223 is formed between the second to second sub-trench T221 and the second to second sub-trench T222.

[0112] The first-second-first groove T121 has a first-second-first depth d121, the first-second-second groove T122 has a first-second-second depth d122, and the first-second-third groove T123 has a first-second-third depth d123. The first-second-third depth d123 is greater than the first-second-second depth d122, and the first-second-first depth d121 is greater than the first-second-third depth d123. Additionally, the first-second-second depth d122 is greater than the third-second depth d32. The second-second-first groove T221 has a second-second-first depth d221, the second-second-second groove T222 has a second-second-second depth d222, and the second-second-third groove T223 has a second-second-third depth d223. The second-second-third depth d223 is greater than the second-second-second depth d222, and the second-second-first depth d221 is greater than the second-second-third depth d223.

[0113] For example, the depth of the first-second groove T12 increases from the third foldable region FA3 towards the first non-foldable region NFA1, and the depth of the second-second groove T22 increases from the third foldable region FA3 towards the second non-foldable region NFA2. For example, the depth of the first-second groove T12 decreases from the first non-foldable region NFA1 towards the third foldable region FA3, and the depth of the second-second groove T22 decreases from the second non-foldable region NFA2 towards the third foldable region FA3. Additionally, the first-second angle θ12 of the first-second slope SL12 is further decreased, and the second-second angle θ22 of the second-second slope SL22 is further decreased. Accordingly, the upper adhesive layer UAL can move more easily along the slope of the second protective layer R2. For example, when the display device 1 is folded, a part of a component such as the protective film PF attached to the cover window CW does not detach from the cover window CW.

[0114] Figure 12 is a schematic cross-sectional view of a part of the display panel 10 in the display device 1 according to an embodiment. As will be appreciated by those of ordinary skill in the art, the display panel 10 may have various configurations other than the Figure 12 configuration shown.

[0115] As Figure 12As shown in the figure, in the embodiment, the display panel 10 includes a substrate 100, a pixel circuit layer 200, a display element layer 300, and a packaging layer 400. The substrate 100 includes at least one of glass, metal, and polymer resin. The substrate 100 is flexible or bendable. For example, the substrate 100 includes at least one polymer resin such as polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, and cellulose acetate propionate. The substrate 100 may have a multilayer structure including two layers each including a polymer resin and a barrier layer including an inorganic material such as silicon oxide (SiO x ), silicon nitride (SiN x ), and silicon oxynitride (SiO x N y ) between the two layers. However, the embodiment is not limited thereto, and various modifications may be made in other embodiments.

[0116] The pixel circuit layer 200 is disposed on the substrate 100. The pixel circuit layer 200 includes a thin film transistor TFT, an inorganic insulating layer IIL, and an organic insulating layer OIL. The thin film transistor TFT includes a semiconductor layer Act, a gate electrode GE, a source electrode SE, and a drain electrode DE. The inorganic insulating layer IIL includes a gate insulating layer IIL1, a first interlayer insulating layer IIL2, and a second interlayer insulating layer IIL3.

[0117] The semiconductor layer Act is disposed on the substrate 100. In the embodiment, the semiconductor layer Act includes polysilicon. In other embodiments, the semiconductor layer Act includes at least one of amorphous silicon, oxide semiconductor, and organic semiconductor. In the embodiment, the semiconductor layer Act includes a channel region and a source region and a drain region respectively disposed on each side of the channel region.

[0118] The gate insulating layer IIL1 is disposed on the semiconductor layer Act and the substrate 100. The gate insulating layer IIL1 includes at least one inorganic insulating material such as silicon oxide (SiO x ), silicon nitride (SiN x ), silicon oxynitride (SiO x N y ), aluminum oxide (Al2O3), titanium oxide (TiO2), tantalum oxide (Ta2O5), hafnium oxide (HfO2), and zinc oxide (ZnO x ). Zinc oxide (ZnO x ) includes at least one of zinc oxide (ZnO) and zinc peroxide (ZnO2).

[0119] The gate electrode GE is disposed on the gate insulating layer IIL1. For example, since the gate insulating layer IIL1 is disposed between the semiconductor layer Act and the gate electrode GE, insulation between the semiconductor layer Act and the gate electrode GE is ensured. The gate electrode GE overlaps with the channel region of the semiconductor layer Act. The gate electrode GE includes a low-resistance metal. In an embodiment, the gate electrode GE includes a conductive material containing at least one of molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), etc., and may have a single-layer or multi-layer structure including the conductive material.

[0120] The first interlayer insulating layer IIL2 is disposed on the gate electrode GE and the gate insulating layer IIL1. The first interlayer insulating layer IIL2 includes an inorganic insulating material such as SiO x , SiN x , SiO x N y , Al2O3, TiO2, Ta2O5, HfO2, and ZnO x and at least one of them.

[0121] The source electrode SE and the drain electrode DE are disposed on the first interlayer insulating layer IIL2. Each of the source electrode SE and the drain electrode DE is connected to the semiconductor layer Act through a contact hole formed in the gate insulating layer IIL1 and the first interlayer insulating layer IIL2. At least one of the source electrode SE and the drain electrode DE includes a conductive material such as at least one of Mo, Al, Cu, and Ti, and may have a single-layer or multi-layer structure including the conductive material. In an embodiment, at least one of the source electrode SE and the drain electrode DE has a multi-layer structure including a Ti / Al / Ti layer.

[0122] The second interlayer insulating layer IIL3 is disposed on the source electrode SE, the drain electrode DE, and the first interlayer insulating layer IIL2. The second interlayer insulating layer IIL3 includes an inorganic insulating material such as SiO x , SiN x , SiO x N y , Al2O3, TiO2, Ta2O5, HfO2, and ZnO x and at least one of them.

[0123] The organic insulating layer OIL is disposed on the second interlayer insulating layer IIL3. The organic insulating layer OIL substantially planarizes the upper part of the pixel circuit layer 200. The organic insulating layer OIL includes an organic material such as at least one of acrylic acid, benzocyclobutene (BCB), and hexamethyldisiloxane (HMDSO). Although Figure 10 it is shown that the organic insulating layer OIL includes a single layer, various modifications such as multiple layers can be made.

[0124] In addition, the pixel circuit layer 200 may include a storage capacitor. Although Figure 12 the pixel circuit layer 200 is shown to include one transistor, embodiments of the present disclosure are not necessarily limited thereto. For example, the number of transistors or the number of storage capacitors may vary depending on the design of the pixel circuit layer 200.

[0125] The display element layer 300 is disposed on the pixel circuit layer 200. The display element layer 300 includes a display element 310 and a pixel defining layer 320. The display element 310 is electrically connected to the thin film transistor TFT. The display element 310 may be, for example, an organic light emitting diode including a pixel electrode 311, a counter electrode 313, and an intermediate layer 312 disposed between the pixel electrode 311 and the counter electrode 313 and including an emission layer. The fact that the display element 310 is electrically connected to the thin film transistor TFT may be understood as the fact that the pixel electrode 311 of the organic light emitting diode is electrically connected to the thin film transistor TFT.

[0126] The pixel electrode 311 is electrically connected to the thin film transistor TFT by contacting the source electrode SE or the drain electrode DE through a contact hole formed in the second interlayer insulating layer IIL3 and the organic insulating layer OIL. The pixel electrode 311 includes at least one conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide (In2O3), indium gallium oxide (IGO), and aluminum zinc oxide (AZO). In an embodiment, the pixel electrode 311 includes a reflective layer including at least one of silver (Ag), magnesium (Mg), aluminum (Al), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), and compounds thereof. In an embodiment, the pixel electrode 311 further includes a layer including at least one of ITO, IZO, ZnO, and In2O3 above / below the reflective layer.

[0127] The pixel defining layer 320 covers the edge of the pixel electrode 311. The pixel defining layer 320 includes a pixel opening, and the pixel opening overlaps with the pixel electrode 311. The pixel opening defines an emission region of light emitted from the display element 310. The pixel defining layer 320 includes an organic insulating material and / or an inorganic insulating material. In some embodiments, the pixel defining layer 320 includes a light-shielding material.

[0128] The intermediate layer 312 is disposed on the pixel electrode 311 and the pixel defining layer 320. The intermediate layer 312 includes a low molecular weight or high molecular weight material. When the intermediate layer 312 includes a low molecular weight material, the intermediate layer 312 has a structure in which a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), an electron injection layer (EIL), etc. are stacked in a single or complex structure and formed by a vacuum deposition method. When the intermediate layer 312 includes a high molecular weight material, the intermediate layer 312 has a structure including an HTL and an EML. For example, the HTL includes PEDOT, and the EML includes a high molecular weight material such as at least one of polystyrene (PPV) and polyfluorene. The intermediate layer 312 can be formed by screen printing, inkjet printing, laser induced thermal imaging (LITI), etc. The intermediate layer 312 is not limited thereto, and in other embodiments, it can have various other structures. In addition, the intermediate layer 312 can include a layer extending across a plurality of pixel electrodes 311, or can include a layer patterned to correspond to each of the plurality of pixel electrodes 311.

[0129] The counter electrode 313 is disposed on the intermediate layer 312 and the pixel defining layer 320. The counter electrode 313 is integrally formed in a plurality of organic light emitting diodes and corresponds to the plurality of pixel electrodes 311. The counter electrode 313 includes a light-transmissive conductive layer including at least one of ITO, In2O3, and IZO, and may further include a semi-transmissive layer including a metal such as Al or Ag. For example, the counter electrode 313 is a semi-transmissive layer including Mg or Ag.

[0130] The display element 310 may be easily damaged by external moisture or oxygen, and thus, the encapsulation layer 400 covers the display element 310 to protect the display element 310. As Figure 12 shown, the encapsulation layer 400 includes a first inorganic encapsulation layer 410, an organic encapsulation layer 420, and a second inorganic encapsulation layer 430.

[0131] The first inorganic encapsulation layer 410 covers the counter electrode 313 and includes SiO x , SiN x , and SiO x N y at least one of. As needed, other layers such as a capping layer can be disposed between the first inorganic encapsulation layer 410 and the counter electrode 313. As Figure 12As shown, since the first inorganic encapsulation layer 410 is formed along the structure thereunder, the upper surface of the first inorganic encapsulation layer 410 is not flat. The organic encapsulation layer 420 covers the first inorganic encapsulation layer 410, and different from the first inorganic encapsulation layer 410, the upper surface of the organic encapsulation layer 420 is substantially flat. The organic encapsulation layer 420 includes one or more of polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, and hexamethyldisiloxane. The second inorganic encapsulation layer 430 covers the organic encapsulation layer 420 and includes SiO x , SiN x and SiO x N y at least one of.

[0132] As described above, the encapsulation layer 400 includes the first inorganic encapsulation layer 410, the organic encapsulation layer 420, and the second inorganic encapsulation layer 430, and thus, even when cracks occur due to the multi-layer structure of the encapsulation layer 400, the cracks can be interrupted between the first inorganic encapsulation layer 410 and the organic encapsulation layer 420 or between the organic encapsulation layer 420 and the second inorganic encapsulation layer 430. Accordingly, the formation of paths through which external moisture or oxygen can penetrate into the display panel 10 can be prevented or reduced.

[0133] Although the display device 1 has been described above, embodiments of the present disclosure are not necessarily limited thereto. It can be said that the method of manufacturing the display device 1 also falls within the scope of the present disclosure. Hereinafter, the method of manufacturing the display device 1 will be described.

[0134] Figures 13 to 18 is a schematic cross-sectional view illustrating the process of manufacturing Figure 3 the display device 1. For example, Figures 13 to 18 is a schematic cross-sectional view illustrating the process of forming Figure 3 the cover window CW of the display device 1. In Figures 13 to 18 , for ease of explanation, the method of manufacturing the display device 1 will be described based on Figure 3 the area A of the display device 1. Hereinafter, when describing the process of manufacturing Figures 13 to 18 the display device 1 with reference to Figure 3 , reference numerals identical to those in Figures 1 to 6 the drawings may represent the same components, and repeated descriptions may be omitted.

[0135] First, as shown in Figure 13 and Figure 14As shown, a window W is provided. The window W includes a first non-foldable region NFA1, a second non-foldable region NFA2, and a foldable region FA, and the window W has a first window surface WS1 and a second window surface WS2 opposite to the first window surface WS1. A plurality of grooves T are formed in the foldable region FA of the window W.

[0136] For example, the plurality of grooves T include a first groove T1 and a second groove T2. The first groove T1 is formed in the first window surface WS1, and the second groove T2 is formed in the second window surface WS2. In a plan view, the grooves T formed in the first window surface WS1 and the grooves T formed in the second window surface WS2 are alternately arranged. For example, in the plan view, the first groove T1 and the second groove T2 are alternately arranged.

[0137] The depth of the grooves T formed adjacent to the first non-foldable region NFA1 and the depth of the grooves T formed adjacent to the second non-foldable region NFA2 are greater than the depth of the grooves T formed in the central region of the foldable region FA. As described above, the foldable region FA includes a first foldable region FA1, a second foldable region FA2, and a third foldable region FA3. The first foldable region FA1 is adjacent to the first non-foldable region NFA1, and the second foldable region FA2 is adjacent to the second non-foldable region NFA2. The third foldable region FA3 is disposed between the first foldable region FA1 and the second foldable region FA2.

[0138] The first groove T1 includes a 1-1 groove T11 formed in the first foldable region FA1, a 2-1 groove T21 formed in the second foldable region FA2, and a 3-1 groove T31 formed in the third foldable region FA3. As Figure 13 shown, the 1-1 groove T11 has a 1-1 depth d11, and the 3-1 groove T31 has a 3-1 depth d31. The 1-1 depth d11 is greater than the 3-1 depth d31. The 2-1 groove T21 has a 2-1 depth d21, and the 2-1 depth d21 is greater than the 3-1 depth d31. As Figure 14 shown, the second groove T2 includes a 1-2 groove T12 formed in the first foldable region FA1, a 2-2 groove T22 formed in the second foldable region FA2, and a 3-2 groove T32 formed in the third foldable region FA3. The 1-2 groove T12 has a 1-2 depth d12, and the 3-2 groove T32 has a 3-2 depth d32. The 1-2 depth d12 is greater than the 3-2 depth d32. The 2-2 groove T22 has a 2-2 depth d22, and the 2-2 depth d22 is greater than the 3-2 depth d32. Since forming the grooves T in the window W is a common aspect in manufacturing a display device, its detailed description is omitted.

[0139] Next, as Figure 15 shown in, the release film is attached to the window W by using a release film adhesive layer. For example, the first release film RF1 is attached to the window W by using a first release film adhesive layer RFa1 provided on the first window surface WS1 of the first non-fold region NFA1 and the second non-fold region NFA2. For example, the first release film adhesive layer RFa1 includes a first-1 release film adhesive layer RFa11 and a first-2 release film adhesive layer RFa12. The first-1 release film adhesive layer RFa11 is provided between the first release film RF1 and the first non-fold region NFA1, and the first-2 release film adhesive layer RFa12 is provided between the first release film RF1 and the second non-fold region NFA2. For example, the first-1 release film adhesive layer RFa11 is disposed adjacent to the first-1 groove T11, and the first-2 release film adhesive layer RFa12 is disposed adjacent to the second-1 groove T21.

[0140] Accordingly, a gap equal to the thickness of the first release film adhesive layer RFa1 is formed between the first window surface WS1 of the foldable region FA and the upper surface (in the +z direction) of the first release film RF1. Accordingly, in a cross-sectional view taken along a plane perpendicular to the window W and passing through a portion of the first release film adhesive layer RFa1, the first release film RF1, and the window W that forms the first groove T1, a first space SP1 surrounded by the first release film adhesive layer RFa1, the first release film RF1, and the portion of the window W that forms the first groove T1 is defined.

[0141] Similarly, the second release film RF2 is attached to the window W by using a second release film adhesive layer RFa2 provided on the second window surface WS2 of the first non-fold region NFA1 and the second non-fold region NFA2. For example, the second release film adhesive layer RFa2 includes a second-1 release film adhesive layer RFa21 and a second-2 release film adhesive layer RFa22. The second-1 release film adhesive layer RFa21 is provided between the second release film RF2 and the first non-fold region NFA1, and the second-2 release film adhesive layer RFa22 is provided between the second release film RF2 and the second non-fold region NFA2. For example, the second-1 release film adhesive layer RFa21 is disposed adjacent to the first-2 groove T12, and the second-2 release film adhesive layer RFa22 is disposed adjacent to the second-2 groove T22.

[0142] Accordingly, a gap equal to the thickness of the second release film adhesive layer RFa2 is formed between the second window surface WS2 of the foldable region FA and the lower surface (in the -z direction) of the second release film RF2. Accordingly, in a cross-sectional view taken along a plane perpendicular to the window W and passing through the portion of the second release film adhesive layer RFa2, the second release film RF2, and the window W where the second groove T2 is formed, a second space SP2 surrounded by the second release film adhesive layer RFa2, the second release film RF2, and the portion of the window W where the second groove T2 is formed is defined.

[0143] Each of the first release film RF1 and the second release film RF2 includes at least one of polyethylene terephthalate (PET), polyimide (PI), polyamide-imide (PAI), polypropylene (PP), polystyrene (PS), and the like. However, embodiments of the present disclosure are not necessarily limited thereto. As described below, a structure that defines a space filled with a protective layer composition can be used in the first release film RF1 and the second release film RF2 without limitation. Each of the first release film adhesive layer RFa1 and the second release film adhesive layer RFa2 includes an adhesive member such as OCA or PSA.

[0144] Figure 16 is a cross-sectional view taken along a plane perpendicular to the window W and passing through the portion of the release film adhesive layer, the release film, and the window W where a plurality of grooves T are formed. As Figure 16 shown, a space surrounded by the release film adhesive layer, the release film, and the portion of the window W where a plurality of grooves T are formed is formed, and the space is filled with a protective layer composition.

[0145] For example, the first space SP1 is filled with the first protective layer composition PR1. The first protective layer composition PR1 is filled in the first space SP1 by capillary action. For example, the first protective layer composition PR1 is filled in the first groove T1 and the gap between the first window surface WS1 of the foldable region FA and the upper surface (in the +z direction) of the first release film RF1 by capillary action. Since the depth of the 1-1 groove T11 is greater than the depth of the 3-1 groove T31, the volume of the first protective layer composition PR1 filled in the 1-1 groove T11 is greater than the volume of the first protective layer composition PR1 filled in the 3-1 groove T31. Since the depth of the 2-1 groove T21 is greater than the depth of the 3-1 groove T31, the volume of the first protective layer composition PR1 filled in the 2-1 groove T21 is greater than the volume of the first protective layer composition PR1 filled in the 3-1 groove T31.

[0146] The first protective layer composition PR1 includes monomers and / or polymers that form the first protective layer R1. The first protective layer R1 includes at least one of silicone resins, OCR, and OCA. For example, the first protective layer R1 is formed by curing the first protective layer composition PR1. The first protective layer composition PR1 may further include a photoinitiator. The first protective layer composition PR1 includes, but is not particularly limited to, a photoinitiator as long as the photoinitiator can be used for photocuring the monomers and / or polymers used to form the first protective layer R1. In an embodiment, the first protective layer composition PR1 further includes a solvent. The solvent in the first protective layer composition PR1 is any solvent that can dissolve the monomers and / or polymers that form the first protective layer R1 and is not particularly limited. For example, the first protective layer composition PR1 is a solution in which the monomers and / or polymers that form the first protective layer R1 and the photoinitiator are dissolved in the solvent.

[0147] Similarly, the second space SP2 is filled with the second protective layer composition PR2. The second protective layer composition PR2 is filled in the second space SP2 by capillary action. For example, the second protective layer composition PR2 is filled by capillary action in the second trench T2 and the gap between the second window surface WS2 of the foldable region FA and the lower surface (in the -z direction) of the second release film RF2. Since the depth of the 1-2 trench T12 is greater than the depth of the 3-2 trench T32, the volume of the second protective layer composition PR2 filled in the 1-2 trench T12 is greater than the volume of the second protective layer composition PR2 filled in the 3-2 trench T32. Since the depth of the 2-2 trench T22 is greater than the depth of the 3-2 trench T32, the volume of the second protective layer composition PR2 filled in the 2-2 trench T22 is greater than the volume of the second protective layer composition PR2 filled in the 3-2 trench T32.

[0148] The second protective layer composition PR2 includes monomers and / or polymers that form the second protective layer R2. The second protective layer R2 includes at least one of silicone resins, OCR, and OCA. For example, the second protective layer R2 is formed by curing the second protective layer composition PR2. The second protective layer composition PR2 may further include a photoinitiator. The second protective layer composition PR2 includes, but is not particularly limited to, a photoinitiator as long as the photoinitiator can be used for photocuring the monomers and / or polymers that form the second protective layer R2. In an embodiment, the second protective layer composition PR2 further includes a solvent. The solvent in the second protective layer composition PR2 is any solvent that can dissolve the monomers and / or polymers that form the second protective layer R2 and is not particularly limited. For example, the second protective layer composition PR2 is a solution in which the monomers and / or polymers that form the second protective layer R2 and the photoinitiator are dissolved in the solvent.

[0149] Next, asFigure 17 As shown, ultraviolet light is irradiated onto the protective layer composition. For example, the first protective layer R1 is formed by irradiating ultraviolet light onto the first protective layer composition PR1, and the second protective layer R2 is formed by irradiating ultraviolet light onto the second protective layer composition PR2. For example, ultraviolet light having a light intensity between about 100 mJ / cm 2 and about 1000 mJ / cm 2 is irradiated onto the first protective layer composition PR1 and the second protective layer composition PR2. Ultraviolet light having a wavelength between about 300 nm and about 400 nm is used for photocuring. A light-emitting diode (LED) or metal halide can be used as the ultraviolet light source.

[0150] The volume of the first protective layer R1 is smaller than the volume of the first protective layer composition PR1 used to form the first protective layer R1. For example, the first protective layer R1 has shrunk. Generally, the larger the volume of the composition, the greater the degree of shrinkage of the layer formed from the composition. Since the volume of the first protective layer composition PR1 filled in the 1-1 trench T11 is larger than the volume of the first protective layer composition PR1 filled in the 3-1 trench T31, the degree of shrinkage of the first protective layer R1 filled in the 1-1 trench T11 is greater than the degree of shrinkage of the first protective layer R1 filled in the 3-1 trench T31. Therefore, the volume of the portion of the first protective layer R1 formed by the first protective layer composition PR1 filling the space below the 1-1 trench T11 and the 1-1 trench T11 is larger than the volume of the portion of the first protective layer R1 formed by the first protective layer composition PR1 filling the space below the 3-1 trench T31 and the 3-1 trench T31.

[0151] Accordingly, the shortest distance between the virtual extension surface parallel to the first window surface WS1 and the lower surface (in the -z direction) of the portion of the first protective layer R1 provided below the 1-1 trench T11 is smaller than the shortest distance between the virtual extension surface parallel to the first window surface WS1 and the lower surface (in the -z direction) of the portion of the first protective layer R1 provided below the 3-1 trench T31. For example, the portion of the first protective layer R1 provided below the portion adjacent to the first non-foldable area NFA1 in the foldable area FA has an inclined surface.

[0152] The above description of the shortest distance between the virtual extension surface parallel to the first window surface WS1 and the lower surface (in the -z direction) of the portion of the first protective layer R1 disposed below the 1-1 trench T11 also applies to the shortest distance between the virtual extension surface parallel to the first window surface WS1 and the lower surface (in the -z direction) of the portion of the first protective layer R1 disposed below the 2-1 trench T21. Accordingly, another portion of the first protective layer R1 disposed below the portion of the foldable region FA adjacent to the second non-foldable region NFA2 has an inclined surface.

[0153] Similarly, since the volume of the second protective layer composition PR2 filled in the 1-2 trench T12 is larger than the volume of the second protective layer composition PR2 filled in the 3-2 trench T32, the degree of shrinkage of the second protective layer R2 filled in the 1-2 trench T12 is greater than the degree of shrinkage of the second protective layer R2 filled in the 3-2 trench T32. Therefore, the volume of the portion of the second protective layer R2 formed by filling the space above the 1-2 trench T12 and the second protective layer composition PR2 in the 1-2 trench T12 is larger than the volume of the portion of the second protective layer R2 formed by filling the space above the 3-2 trench T32 and the second protective layer composition PR2 in the 3-2 trench T32.

[0154] Accordingly, the shortest distance between the virtual extension surface parallel to the second window surface WS2 and the upper surface (in the +z direction) of the portion of the second protective layer R2 disposed above the 1-2 trench T12 is less than the shortest distance between the virtual extension surface parallel to the second window surface WS2 and the upper surface (in the +z direction) of the portion of the second protective layer R2 disposed above the 3-2 trench T32. For example, a portion of the second protective layer R2 disposed in the portion of the foldable region FA adjacent to the first non-foldable region NFA1 has an inclined surface.

[0155] The above description of the shortest distance between the virtual extension surface parallel to the second window surface WS2 and the upper surface (in the +z direction) of the portion of the second protective layer R2 disposed above the 1-2 trench T12 also applies to the shortest distance between the virtual extension surface parallel to the second window surface WS2 and the upper surface (in the +z direction) of the portion of the second protective layer R2 disposed above the 2-2 trench T22. Accordingly, another portion of the second protective layer R2 disposed in the portion of the foldable region FA adjacent to the second non-foldable region NFA2 has an inclined surface.

[0156] In an embodiment, before ultraviolet light is irradiated onto the first protective layer composition PR1 and the second protective layer composition PR2, the first protective layer composition PR1 and the second protective layer composition PR2 are heated to remove the solvent contained in the first protective layer composition PR1 and the solvent contained in the second protective layer composition PR2. Thereafter, ultraviolet light is irradiated onto the first protective layer composition PR1 and the second protective layer composition PR2.

[0157] Next, as Figure 18 shown, the release film adhesive layer and the release film are removed from the window W. For example, the first release film adhesive layer RFa1, the second release film adhesive layer RFa2, the first release film RF1, and the second release film RF2 are removed from the window W. Accordingly, a cover window CW including the window W, the first protective layer R1, and the second protective layer R2 is formed.

[0158] In the above embodiment, a plurality of grooves T are alternately located on both sides of the window W. For example, a part of the plurality of grooves T is formed in the first window surface WS1, and another part of the plurality of grooves T is formed in the second window surface WS2. However, the embodiments of the present disclosure are not necessarily limited thereto. In an embodiment, the plurality of grooves T are located on one side of the window W. For example, all of the plurality of grooves T are formed in one surface of the window W.

[0159] For example, as is Figure 19 shown in a schematic plan view of a part of a display device according to an embodiment, all of the plurality of grooves T are formed in the second window surface WS2. For example, the plurality of grooves T include a second groove T2, and the second groove T2 includes a first-2 groove T12, a second-2 groove T22, and a third-2 groove T32. The first-2 groove T12 is formed in the first foldable area FA1, the second-2 groove T22 is formed in the second foldable area FA2, and the third-2 groove T32 is formed in the third foldable area FA3. No groove T is formed in the first window surface WS1. The cover window CW includes the second protective layer R2, but does not include the first protective layer R1.

[0160] For example, as is Figure 20 shown in a schematic plan view of a part of a display device according to an embodiment, all of the plurality of grooves T are formed in the first window surface WS1. For example, the plurality of grooves T include a first groove T1, and the first groove T1 includes a first-1 groove T11, a second-1 groove T21, and a third-1 groove T31. The first-1 groove T11 is formed in the first foldable area FA1, the second-1 groove T21 is formed in the second foldable area FA2, and the third-1 groove T31 is formed in the third foldable area FA3. No groove T is formed in the second window surface WS2. The cover window CW includes the first protective layer R1, but does not include the second protective layer R2.

[0161] According to embodiments of the present disclosure as described above, a display device and a method of manufacturing the display device are realized in which a part of a member attached to a cover window does not come off from the cover window when the display device is folded. However, the scope of embodiments of the present disclosure is not limited by these effects.

[0162] It should be understood that the embodiments described herein should be considered only in a descriptive sense and not for purposes of limitation. The description of features or aspects within each embodiment should generally be considered available for other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the figures, those of ordinary skill in the art will understand that various changes may be made in form and detail without departing from the spirit and scope defined by the claims.

Claims

1. A display device, comprising: A display panel including a display element; as well as A cover window is disposed on the display panel, and the cover window includes a window, a first protective layer and a second protective layer, The window includes a first non-folding area, a second non-folding area, and a foldable area between the first non-folding area and the second non-folding area. A plurality of grooves are formed in the foldable region, and A depth of the groove formed adjacent to the first non-folding region and a depth of the groove formed adjacent to the second non-folding region are greater than a depth of the groove formed in the central region of the foldable region.

2. The display device according to claim 1, wherein: the window includes a first window surface in a direction facing the display panel and a second window surface in a direction opposite to the direction facing the display panel, The plurality of grooves include a first groove formed in the first window surface and a second groove formed in the second window surface, and In a plan view, the first grooves and the second grooves are arranged alternately.

3. The display device according to claim 2, wherein: The foldable region includes a first foldable region adjacent to the first non-foldable region, a second foldable region adjacent to the second non-foldable region, and a third foldable region located between the first foldable region and the second foldable region. The first grooves include a 1-1 groove formed in the first foldable region, a 2-1 groove formed in the second foldable region, and a 3-1 groove formed in the third foldable region, and The depth of the 1-1 groove and the depth of the 2-1 groove are each greater than the depth of the 3-1 groove.

4. The display device according to claim 3, wherein: The first protective layer is disposed in the foldable region, and a portion of the first protective layer has a slope.

5. The display device according to claim 4, wherein: The portion of the first protective layer disposed in the first foldable region has a 1-1 slope, and A portion of the first protective layer disposed in the second foldable region has a 2-1 slope.

6. The display device according to claim 3, wherein: The 1-1 groove includes a 1-1-1 groove, a 1-1-2 groove and a 1-1-3 groove, The 1-1-1 groove is formed in a portion of the first foldable region adjacent to the first non-folding region, The 1-1-2 groove is formed in a portion of the first foldable region adjacent to the third foldable region, The 1-1-3 groove is formed in a portion of the first foldable region between the portion of the first foldable region where the 1-1-1 groove is formed and the portion of the first foldable region where the 1-1-2 groove is formed, The depth of the 1-1-3 groove is greater than the depth of the 1-1-2 groove, and The depth of the 1-1-1 groove is greater than the depth of the 1-1-3 groove.

7. The display device according to claim 3, wherein: The 2-1 groove includes a 2-1-1 groove, a 2-1-2 groove and a 2-1-3 groove, The 2-1-1 groove is formed in a portion of the second foldable region adjacent to the second non-folding region, The 2-1-2 groove is formed in a portion of the second foldable region adjacent to the third foldable region, The 2-1-3 groove is formed in a portion of the second foldable region between the portion of the second foldable region where the 2-1-1 groove is formed and the portion of the second foldable region where the 2-1-2 groove is formed, The depth of the 2-1-3 groove is greater than the depth of the 2-1-2 groove, and The depth of the 2-1-1 groove is greater than the depth of the 2-1-3 groove.

8. The display device according to any one of claims 3 to 7, further comprising: The lower adhesive layer is disposed between the display panel and the cover window.

9. The display device according to claim 3, wherein: The second grooves include a 1-2 groove formed in the first foldable region, a 2-2 groove formed in the second foldable region, and a 3-2 groove formed in the third foldable region, and The depth of the 1-2 groove and the depth of the 2-2 groove are each greater than the depth of the 3-2 groove.

10. The display device according to claim 9, wherein: The second protective layer is disposed in the foldable region, and A portion of the second protective layer has a slope.

11. The display device according to claim 10, wherein: The portion of the second protective layer disposed in the first foldable region has a 1-2 slope, and A portion of the second protective layer disposed in the second foldable region has a 2-2 slope.

12. The display device according to claim 9, wherein: The 1-2 groove includes a 1-2-1 groove, a 1-2-2 groove and a 1-2-3 groove, The 1-2-1 groove is formed in a portion of the first foldable region adjacent to the first non-folding region, The 1-2-2 groove is formed in a portion of the first foldable region adjacent to the third foldable region, The 1-2-3 groove is formed in a portion of the first foldable region between the portion of the first foldable region where the 1-2-1 groove is formed and the portion of the first foldable region where the 1-2-2 groove is formed, The depth of the 1-2-3 groove is greater than the depth of the 1-2-2 groove, and The depth of the 1-2-1 groove is greater than the depth of the 1-2-3 groove.

13. The display device according to claim 9, wherein: The 2-2 groove includes a 2-2-1 groove, a 2-2-2 groove and a 2-2-3 groove, The 2-2-1 groove is formed in a portion of the second foldable region adjacent to the second non-folding region, The 2-2-2 groove is formed in a portion of the second foldable region adjacent to the third foldable region, The 2-2-3 groove is formed in a portion of the second foldable region between the portion of the second foldable region where the 2-2-1 groove is formed and the portion of the second foldable region where the 2-2-2 groove is formed, The depth of the 2-2-3 groove is greater than the depth of the 2-2-2 groove, and The depth of the 2-2-1 groove is greater than the depth of the 2-2-3 groove.

14. The display device according to claim 8, further comprising: a protective film disposed on the cover window, and An upper adhesive layer is disposed between the cover window and the protective film.

15. A method for manufacturing a display device, the method comprising: Providing a window including a first non-folding area, a second non-folding area, and a foldable area between the first non-folding area and the second non-folding area, wherein a plurality of grooves are formed in the foldable area; attaching a release film to the window by using a release film adhesive layer; filling a space with a protective layer composition, wherein the space is surrounded by the release film adhesive layer, the release film, and a portion of the window in which the plurality of grooves are formed; irradiating ultraviolet light onto the protective layer composition; and removing the release film adhesive layer and the release film from the window, Wherein, the depth of the groove formed adjacent to the first unfolded area and the depth of the groove formed adjacent to the second unfolded area are greater than the depth of the groove formed in the central area of ​​the foldable area.

16. The method according to claim 15, wherein: The window comprises a first window surface and a second window surface opposite to the first window surface, The plurality of grooves include a first groove formed in the first window surface and a second groove formed in the second window surface, and In a plan view, the first grooves and the second grooves are arranged alternately.

17. The method according to claim 16, wherein: The foldable region includes a first foldable region adjacent to the first non-foldable region, a second foldable region adjacent to the second non-foldable region, and a third foldable region located between the first foldable region and the second foldable region. The first grooves include a 1-1 groove formed in the first foldable region, a 2-1 groove formed in the second foldable region, and a 3-1 groove formed in the third foldable region, and The depth of the 1-1 groove and the depth of the 2-1 groove are each greater than the depth of the 3-1 groove.

18. The method according to claim 17, wherein: The second grooves include a 1-2 groove formed in the first foldable region, a 2-2 groove formed in the second foldable region, and a 3-2 groove formed in the third foldable region, and The depth of the 1-2 groove and the depth of the 2-2 groove are each greater than the depth of the 3-2 groove.

19. The method according to any one of claims 16 to 18, wherein: Attaching the release film comprises: attaching a first release film to the window by using a first release film adhesive layer disposed on a surface of the first window in the first non-folding region and the second non-folding region; and A second release film is attached to the window by using a second release film adhesive layer disposed on the second window surface of the first non-folding area and the second non-folding area.

20. The method according to claim 19, wherein: Filling the space with the protective layer composition comprises: filling a first space with a first protective layer composition, wherein the first space is surrounded by the first release film adhesive layer, the first release film, and a portion of the window in which the first groove is formed; and A second space is filled with a second protective layer composition, wherein the second space is surrounded by the second release film adhesive layer, the second release film, and a portion of the window in which the second groove is formed.

21. The method according to claim 20, wherein: The irradiating the ultraviolet light comprises: forming a first protective layer by irradiating the ultraviolet light onto the first protective layer composition; and The second protective layer is formed by irradiating the ultraviolet light onto the second protective layer composition.

22. The method according to claim 21, wherein: A portion of the first protective layer disposed in a portion of the foldable region adjacent to the first non-folding region has a first slope, and A portion of the first protective layer disposed in a portion of the foldable region adjacent to the second non-folding region has a second slope.

23. The method according to claim 21, wherein: A portion of the second protective layer disposed in a portion of the foldable region adjacent to the first non-folding region has a first slope, and A portion of the second protective layer disposed in a portion of the foldable region adjacent to the second non-folding region has a second slope.

24. A display device comprising: A display panel including a display element; as well as a cover window disposed on the display panel, wherein the cover window comprises a window, wherein the window comprises a first window surface in a direction facing the display panel and a second window surface in a direction opposite to the direction facing the display panel, and comprises a first non-folding area, a second non-folding area, and a foldable area between the first non-folding area and the second non-folding area, A plurality of grooves are formed in one of the first window surface and the second window surface, and A depth of the groove formed adjacent to the first non-folding region and a depth of the groove formed adjacent to the second non-folding region are greater than a depth of the groove formed in the central region of the foldable region.

25. The display device according to claim 24, in, The cover window further comprises a first protective layer and a second protective layer, in, The first protective layer is arranged in the foldable area, The second protective layer is disposed in the foldable region, and A portion of one of the first protective layer and the second protective layer corresponding to the formation of the plurality of grooves has an inclined surface.

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