Display Devices

Abstract

The present invention relates to a display device including a display module and a window disposed on the display module. The window includes a base layer and a resin, wherein the base layer includes a folding area and a non-folding area, a groove is defined in the folding area, the resin is disposed in the groove and includes a thiol group, wherein the difference between the refractive index of the base layer and the refractive index of the resin is less than about 0.1.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Korean Patent Application No. 10-2020-0052315, filed on April 29, 2020, and all rights arising therefrom, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] Embodiments of the present invention relate to a window and a display device having improved product reliability. Background Art

[0004] A display device displays various images on a display screen to provide information to a user. Generally, a display device displays information within a specified screen. In recent years, flexible display devices including foldable flexible display panels have been developed. Unlike rigid display devices, flexible display devices are deformable, for example, foldable, rollable, or bendable. Flexible display devices that can be formed into various shapes are portable regardless of the existing screen size, thereby improving user convenience. Summary of the invention

[0005] Embodiments of the present invention provide a display device having improved product reliability.

[0006] An embodiment of the present invention provides a window including a base layer and a resin, wherein the base layer includes a folding area and a non-folding area, a groove is defined in the folding area, the resin is arranged in the groove and includes a thiol group, wherein the difference between the refractive index of the base layer and the refractive index of the resin is less than about 0.1.

[0007] In an embodiment, the refractive index of the resin may be about 1.5 to about 1.6.

[0008] In an embodiment, the groove may include a first portion having a circular shape, a second portion spaced apart from the first portion and having a circular shape, and a third portion connecting the first portion and the second portion.

[0009] In an embodiment, the third portion may have a curved shape.

[0010] In an embodiment, the resin may include polydimethylsiloxanethiol.

[0011] In an implementation, the resin may include at least one of a thiol-based cross-linking agent polymerized with polydimethylsiloxanethiol, an acrylic-based cross-linking agent, and a vinyl-based cross-linking agent.

[0012] In an embodiment, a plurality of grooves may be defined in the folding region.

[0013] In an embodiment, the resin may have translucency.

[0014] In an embodiment, the base layer may have a thickness of about 100 micrometers (μm) to about 500 μm.

[0015] In an embodiment of the present invention, a display device includes a display module and a window disposed on the display module, the window including a base layer and a resin, the base layer including a folding area and a non-folding area, a plurality of grooves being defined in the folding area, the resin being disposed in each of the plurality of grooves and including a thiol group, and a difference between a refractive index of the base layer and a refractive index of the resin is less than about 0.1.

[0016] In an embodiment, each of the plurality of grooves may include a first portion having a circular shape, a second portion spaced apart from the first portion and having a circular shape, and a third portion connecting the first portion and the second portion.

[0017] In an implementation, the width of the third portion may include at least one of a first width and a second width greater than the first width.

[0018] In an embodiment, the plurality of grooves may include a first groove defined in a central area of ​​the folding area, a second groove defined in a peripheral area of ​​the folding area, and a third groove defined in the peripheral area and closer to the non-folding area than the second groove is to the non-folding area, and the distance between the first groove and the second groove may be equal to the distance between the second groove and the third groove.

[0019] In an embodiment, the plurality of grooves may include a first groove defined in a central area of ​​the folding area, a second groove defined in a peripheral area of ​​the folding area, and a third groove defined in the peripheral area and closer to the non-folding area than the second groove is to the non-folding area, and the distance between the first groove and the second groove may be smaller than the distance between the second groove and the third groove.

[0020] In an embodiment, the resin may have translucency.

[0021] In an embodiment, the resin may have elasticity.

[0022] In an implementation, the resin may have a refractive index of about 1.5 to about 1.6.

[0023] In an embodiment, the window may have a thickness of about 100 μm to about 500 μm.

[0024] In an embodiment, the resin may include polydimethylsiloxanethiol.

[0025] In an implementation, the resin may include at least one of a thiol-based cross-linking agent polymerized with polydimethylsiloxanethiol, an acrylic-based cross-linking agent, and a vinyl-based cross-linking agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate embodiments of the present invention and together with the description serve to explain the principles of the present invention. In the drawings:

[0027] Figure 1A is a perspective view of an embodiment of a display device according to the present invention;

[0028] Figure 1B is an operational state diagram of an embodiment of a display device according to the present invention;

[0029] Figure 2 is a cross-sectional view of an embodiment of a display device according to the present invention;

[0030] Figure 3 is a cross-sectional view of an embodiment of a display module according to the present invention;

[0031] Figure 4 is a cross-sectional view of an embodiment of an upper layer according to the present invention;

[0032] Figure 5 is a plan view of an embodiment of a window according to the present invention;

[0033] Figure 6 It is shown Figure 5 An enlarged view of an embodiment of region AA shown in FIG.

[0034] Figure 7 is a plan view of an embodiment of a base layer according to the present invention;

[0035] Fig. 8A It is shown Figure 7 An enlarged view of an embodiment of the region AA' shown in FIG.

[0036] Figure 8B It is shown Figure 7 An enlarged view of an embodiment of the region AA' shown in FIG.

[0037] Fig.9A It is shown Figure 5 An enlarged view of an embodiment of region AA shown in FIG.

[0038] Fig. 9B It is shown Figure 5 An enlarged view of an embodiment of region AA shown in FIG.

[0039] Fig.10 is an enlarged plan view showing an embodiment of a portion of a base layer according to the present invention; and

[0040] Fig.11 An embodiment of the resin according to the present invention is schematically shown. DETAILED DESCRIPTION

[0041] In the present disclosure, when an element (or region, layer, part, etc.) is referred to as being "on," "connected to" or "coupled to" another element, it means that the element can be directly set on the other element, directly connected to / directly coupled to the other element, or a third element can be set between them.

[0042] The same reference numerals denote the same elements. In addition, in the drawings, in order to effectively describe the technical contents, the thickness, proportion and size of the elements are exaggerated.

[0043] The term "and / or" includes all combinations of one or more that the relevant configurations can define.

[0044] It will be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the embodiments of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. Unless the context clearly indicates otherwise, a term in the singular may include a plural form.

[0045] In addition, terms such as "below", "lower", "above", "upper", etc. are used to describe the relationship of the configurations shown in the drawings. These terms are used as relative concepts and are described with reference to the directions indicated in the drawings.

[0046] As used herein, "about" or "approximately" includes the stated value and the mean within an acceptable deviation range of the particular value as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations, or within ±30%, ±20%, ±10%, ±5% of the stated value.

[0047] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those skilled in the art to which the inventive concept belongs. It will also be understood that terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and unless explicitly defined as such in this article, they should not be interpreted in an idealized or overly formal sense.

[0048] It should be understood that the terms “include” or “have” are intended to specify the presence of the features, integers, steps, operations, elements, parts or combinations thereof described in the present disclosure, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts or combinations thereof.

[0049] It should be understood that terms such as "substantially the same" are the same, including process errors that may generally occur relative to the numerical range described in the specification. It should be understood that in the specification, the refractive index of the base layer is substantially the same as the refractive index of the resin, indicating that the refractive index of the base layer is the same as the refractive index of the resin, and the difference in the refractive index is very small, so that, for example, the optical path at the interface between the base layer and the resin remains the same.

[0050] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0051] Figure 1A is a perspective view of an embodiment of a display device 1000 according to the present invention. Figure 1B 1 is an operational state diagram of an embodiment of the display device 1000 according to the present invention.

[0052] Reference Figure 1A and Figure 1B , the display device 1000 may be activated according to the electrical signal. In an embodiment, the display device 1000 may be, for example, a mobile phone, a tablet, a car navigation unit, a game console, or a wearable device, but is not limited thereto. Figure 1A , a mobile phone is shown as an embodiment of the display device 1000 .

[0053] The display device 1000 may be a foldable display device. The display device 1000 may sequentially define a first non-folding region 1000NF1, a folding region 1000F, and a second non-folding region 1000NF2 along a first direction DR1. That is, the folding region 1000F may be defined between the first non-folding region 1000NF1 and the second non-folding region 1000NF2.

[0054] exist Figure 1A and Figure 1B , one folding region 1000F and a first non-folding region 1000NF1 and a second non-folding region 1000NF2 are shown, but the number of the folding region 1000F and the first non-folding region 1000NF1 and the second non-folding region 1000NF2 is not limited thereto. In an embodiment, the display device 1000 may include, for example, more than two non-folding regions and a folding region disposed between the non-folding regions.

[0055] The display device 1000 may display an image through the active area 1000A. In the unfolded state, the active area 1000A may include a plane parallel to a plane defined by the first direction DR1 and the second direction DR2. The thickness direction of the display device 1000 may be parallel to a third direction DR3 intersecting the first direction DR1 and the second direction DR2. Therefore, the front surface (or upper surface) and the rear surface (or lower surface) of the member constituting the display device 1000 may be defined relative to the third direction DR3.

[0056] When the display device 1000 is folded, the display surface of the first non-folding region 1000NF1 and the display surface of the second non-folding region 1000NF2 may face each other, and therefore, when the display device 1000 is in a fully folded state, the active area 1000A may not be exposed to the outside. This state may be referred to as an inner folding state. However, this is only an example, and the present invention is not limited thereto.

[0057] When the display device 1000 is folded, the display surface of the first non-folding area 1000NF1 and the display surface of the second non-folding area 1000NF2 may face outward. Therefore, in the folded state, the effective area 1000A may be exposed to the outside. This state may be referred to as an external folding state. In addition, the display device 1000 may be capable of both folding inwardly and folding outwardly. In an embodiment, a folding area 1000F, for example, may be folded inwardly and may be folded outwardly. In an alternative embodiment, the display device 1000 may include a plurality of folding areas, and some of them may be folded inwardly, while others may be folded outwardly.

[0058] Figure 2 is a cross-sectional view of an embodiment of a display device 1000 according to the present invention.

[0059] Reference Figure 2 , the display device 1000 may include a display module 100 , an upper layer 200 , and a lower layer 300 .

[0060] The display module 100 can display an image and sense an external input. The external input can be a user's input. In an embodiment, the user's input can include various forms of external input, such as a part of the user's body, light, heat, a pen, or pressure.

[0061] The display module 100 may include a display panel 110 generating an image and an input sensor 120 acquiring coordinate information of an external input.

[0062] The display panel 110 may be a light-emitting display panel, but is not particularly limited. In an embodiment, the display panel 110 may be, for example, an organic light-emitting display panel or a quantum dot light-emitting display panel. The emission layer of the organic light-emitting display panel may include an organic light-emitting material. The emission layer of the quantum dot light-emitting display panel may include quantum dots, quantum rods, etc.

[0063] The input sensor 120 may be provided on the display panel 110. The input sensor 120 may sense the external input using a mutual capacitance method and / or a self capacitance method. However, the method for sensing the external input is not limited to the above examples.

[0064] The upper layer 200 may be disposed on the display module 100. The display module 100 may display an image in a direction toward the upper layer 200. The upper layer 200 is disposed on the display module 100 to protect the display module 100. A detailed description of the upper layer 200 will be given later.

[0065] The lower layer 300 may be disposed under the display module 100. The lower layer 300 may protect the rear surface of the display module 100. In an embodiment, the lower layer 300 may include a synthetic resin film such as a polyimide film or a polyethylene terephthalate film and a cushion layer disposed under the synthetic resin film to include, for example, sponge, foam, polyurethane resin, etc.

[0066] Figure 3 is a cross-sectional view of an embodiment of a display module 100 according to the present invention.

[0067] Reference Figure 3 , a case where the display panel 110 is an organic light emitting display panel will be described as an example.

[0068] The display panel 110 may include a base layer 111, and a circuit element layer 112, a display element layer 113, and a thin film encapsulation layer 114 sequentially disposed on the base layer 111. Although not separately shown, the display panel 110 may further include functional layers such as a buffer layer and a refractive index control layer.

[0069] The base layer 111 may include a synthetic resin layer. The synthetic resin layer is disposed on a working substrate used in the manufacture of the display panel 110. Thereafter, a conductive layer and an insulating layer are disposed on the synthetic resin layer. When the working substrate is removed, the synthetic resin layer may correspond to the base layer 111. The synthetic resin layer may include a thermosetting resin. In particular, the synthetic resin layer may be a polyimide-based resin layer, and the material is not particularly limited. In addition, the base layer 111 may include a glass substrate, a metal substrate, or an organic / inorganic composite material substrate.

[0070] The circuit element layer 112 includes at least one insulating layer and a circuit element. Hereinafter, the insulating layer included in the circuit element layer 112 may also be referred to as an intermediate insulating layer. The intermediate insulating layer may include at least one intermediate inorganic film and / or at least one intermediate organic film. The circuit element includes a signal line, a pixel driving circuit, etc. The circuit element layer 112 may be provided by a process of forming an insulating layer, a semiconductor layer, and a conductive layer by coating, deposition, etc., and a process of patterning the insulating layer, the semiconductor layer, and the conductive layer by a photolithography process.

[0071] The display element layer 113 includes a light emitting element. The display element layer 113 may include an organic light emitting diode. The display element layer 113 may also include an organic film such as a pixel defining film.

[0072] The thin film encapsulation layer 114 seals the display element layer 113. The thin film encapsulation layer 114 includes at least one insulating layer. The thin film encapsulation layer 114 in the embodiment of the present invention may include at least one inorganic film (hereinafter, also referred to as an inorganic encapsulation film). The thin film encapsulation layer 114 in the embodiment of the present invention may include at least one organic film (hereinafter, also referred to as an organic encapsulation film) and at least one inorganic encapsulation film.

[0073] The inorganic encapsulation film protects the display element layer 113 from moisture / oxygen, and the organic encapsulation film protects the display element layer 113 from external substances such as dust particles. In an embodiment, the inorganic encapsulation film may include, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, an aluminum oxide layer, etc., and is not particularly limited thereto. The organic encapsulation film may include an acryl-based organic film, and is not particularly limited thereto.

[0074] The input sensor 120 may include a base insulating layer 121 , a first conductive layer 122 , a first insulating layer 123 , a second conductive layer 124 , and a second insulating layer 125 .

[0075] The basic insulating layer 121 may be an inorganic layer including any one of silicon nitride, silicon oxynitride, and silicon oxide. In an alternative embodiment, the basic insulating layer 121 may be an organic layer including epoxy resin, acrylic resin, or imide-based resin. The basic insulating layer 121 may be directly disposed on the display panel 110. In an alternative embodiment, the basic insulating layer 121 may be disposed on a separate base layer, and the base layer may be bonded to the basic insulating layer 121 and the display panel 110 by an adhesive member. In an alternative embodiment, the basic insulating layer 121 may be omitted.

[0076] Each of the first conductive layer 122 and the second conductive layer 124 may include a sensing electrode or a signal line. Each of the first conductive layer 122 and the second conductive layer 124 may have a single-layer structure or a multi-layer structure stacked along the third direction DR3. The single-layer conductive layer may include a metal layer or a transparent conductive layer. In an embodiment, the metal layer may include, for example, at least any one of molybdenum, silver, titanium, copper, aluminum, and alloys thereof. In an embodiment, the transparent conductive layer may include a transparent conductive oxide, such as indium tin oxide ("ITO"), indium zinc oxide ("IZO"), zinc oxide (ZnO), or indium tin zinc oxide ("ITZO"). In addition, the transparent conductive layer may include a conductive polymer, such as poly (3,4-ethylenedioxythiophene) ("PEDOT"), metal nanowires, graphene, etc.

[0077] The multi-layer conductive layer may include a multi-layer metal layer. In an embodiment, the multi-layer metal layer may have a three-layer structure of titanium / aluminum / titanium, for example. The multi-layer conductive layer may include at least one metal layer and at least one transparent conductive layer.

[0078] Each of the first insulating layer 123 and the second insulating layer 125 may have a single layer structure or a multi-layer structure. Each of the first insulating layer 123 and the second insulating layer 125 may include an inorganic or organic material or a composite material.

[0079] At least any one of the first insulating layer 123 and the second insulating layer 125 may include an inorganic film. In an implementation, the inorganic film may include, for example, at least one of aluminum oxide, titanium oxide, silicon oxide, silicon oxynitride, zirconium oxide, and hafnium oxide.

[0080] At least any one of the first insulating layer 123 and the second insulating layer 125 may include an organic film. In an embodiment, the organic film may include, for example, at least any one of acrylic-based resin, methacrylic-based resin, polyisoprene, vinyl-based resin, epoxy-based resin, urethane-based resin, cellulose-based resin, siloxane-based resin, polyimide-based resin, polyamide-based resin, and perylene-based resin.

[0081] Figure 4 is a cross-sectional view of an embodiment of an upper layer 200 according to the present invention. Figure 5 is a plan view of an embodiment of a window 220 according to the present invention. Figure 6 It is shown Figure 5 An enlarged view of an embodiment of area AA is shown in FIG.

[0082] Reference Figure 4, the upper layer 200 may include an adhesive layer 210, a window 220, and a functional coating 230 sequentially stacked along the third direction DR3. The adhesive layer 210 may constitute a lower surface 200-B of the upper layer 200, and the functional coating 230 may constitute an upper surface 200-U of the upper layer 200.

[0083] Figure 4 Only examples constituting the upper layer 200 are shown, and the components constituting the upper layer 200 are not limited to the above examples. In an embodiment, the upper layer 200 may, for example, include only at least some of the components described above. In an alternative embodiment, the upper layer 200 may also include other layers in addition to the components described above. In addition, the stacking order of the components constituting the upper layer 200 is not limited to Figure 4 The example shown in .

[0084] The adhesive layer 210 may include a conventional adhesive or glue. In an embodiment, the adhesive layer 210 may be, for example, a transparent adhesive member such as a pressure sensitive adhesive film ("PSA"), an optically clear adhesive film ("OCA"), or an optically clear resin ("OCR").

[0085] The adhesive layer 210 may be disposed on the display module 100 (see Figure 2 The upper layer 200 may be attached to the display module 100 (see Figure 2 ).

[0086] The window 220 may be disposed on the adhesive layer 210. In an embodiment, the window 220 may be in the form of a window layer. The window 220 may include a lower surface 220-B and an upper surface 220-U, wherein the lower surface 220-B faces the adhesive layer 210, the upper surface 220-U is spaced apart from the adhesive layer 210, and the lower surface 220-B is between the upper surface 220-U and the adhesive layer 210.

[0087] The first non-folding region 200NF1, the folding region 200F, and the second non-folding region 200NF2 may be defined in the window 220 along the first direction DR1. That is, the folding region 200F may be defined between the first non-folding region 200NF1 and the second non-folding region 200NF2. Each of the first non-folding region 200NF1, the folding region 200F, and the second non-folding region 200NF2 of the window 220 may correspond to each of the first non-folding region 1000NF1, the folding region 1000F, and the second non-folding region 1000NF2 of the display device 1000 (refer to FIG. 1).

[0088] Reference Figure 5 , the window 220 may include a base layer BS and a resin RS. Although not shown separately, the window 220 may further include a light blocking pattern (not shown). Figure 6 , the window 220 may include a base layer BS and a resin RS disposed in a plurality of grooves HM defined in the base layer BS.

[0089] The base layer BS may be a tempered glass. When the tempered glass is applied to the window 220, the tempered glass has strong scratch resistance compared to the polyimide film to improve the display device 1000 (refer to Figure 1A )'s impact resistance.

[0090] The thickness of the window 220 is the same as that of the base layer BS. In an embodiment, the thickness of the base layer BS may be, for example, about 100 μm to about 500 μm, and preferably about 100 μm to about 400 μm.

[0091] The resin RS may be disposed in each of the grooves HM. In an embodiment, each of the grooves HM may include a first portion PT1 having a circular shape, a second portion PT2 having a circular shape and spaced apart from the first portion PT1, and a third portion PT3 connecting the first portion PT1 and the second portion PT2. The shape of the third portion PT3 is not limited. A detailed description of the resin RS will be described later.

[0092] Figure 7 is a plan view of a base layer BS according to the present invention. Fig. 8A It is shown Figure 7 An enlarged view of an embodiment of area AA' is shown in FIG. Figure 8B It is shown Figure 7 An enlarged view of an embodiment of area AA' is shown in FIG. Figure 8B Show area AA" as Figure 7 An embodiment of the area AA' is shown in FIG.

[0093] Reference Figure 7 , the first non-folding region 220NF1, the folding region 220F, and the second non-folding region 220NF2 may be sequentially defined in the base layer BS along the first direction DR1. That is, the folding region 220F may be defined between the first non-folding region 220NF1 and the second non-folding region 220NF2. The folding region 200F and the non-folding regions 200NF1 and 200NF2 of the window 220 (refer to Figure 4 ) may correspond to the folding region 220F and the non-folding regions 220NF1 and 220NF2 of the base layer BS.

[0094] The base layer BS may overlap the folding region 220F and may be formed along an upper surface 220-U (see Figure 4 ) or lower surface 220-B (refer to Figure 4 ) in the fold axis.

[0095] Refer to Figure 1A and Figure 7 , the base layer BS may be folded like the display device 1000. Each of the first non-folding region 220NF1, the folding region 220F, and the second non-folding region 220NF2 of the base layer BS may correspond to each of the first non-folding region 1000NF1, the folding region 1000F, and the second non-folding region 1000NF2 of the display device 1000.

[0096] To improve the folding property of the window 220 , a plurality of grooves HM may be defined in the folding region 220F of the base layer BS.

[0097] Fig. 8A 1 and 2 show numerical values ​​of the grooves HM. The length H1 indicates a value obtained by measuring the length of each of the grooves HM in the second direction DR2. The length H2 indicates a value obtained by measuring the length of the grooves HM overlapped with each other in the first direction DR1. The length L1 indicates the distance the grooves HM are spaced apart in the first direction DR1. The length L2 indicates the distance the grooves HM are spaced apart in the second direction DR2. The length DI indicates the diameter of the first portion PT1 of each of the grooves HM. The length WD indicates the width of the third portion PT3 of each of the grooves HM in the first direction DR1.

[0098] The value of the groove HM can be adjusted according to the thickness of the base layer BS. In an embodiment, when the thickness of the base layer BS is about 500 microns (μm), the length H1 can be, for example, 2500 μm or more. In an embodiment, the length H2 can be, for example, about 0.2 times to about 0.6 times the length H1. In an embodiment, the diameter DI can be, for example, about 150 μm to about 200 μm. In an embodiment, the width WD can be, for example, about 25 μm to about 30 μm. In an embodiment, the length L1 can be, for example, about 250 μm to about 300 μm. In an embodiment, the length L2 can be, for example, about 500 μm to about 550 μm. However, the present invention is not limited thereto. When the thickness of the base layer BS changes, the values ​​of the lengths H1, H2, DI and WD can change in the same proportion as the thickness change rate of the base layer BS.

[0099] In an embodiment, when the thickness of the base layer BS is about 250 μm, the length H1 may be, for example, about 1250 μm or more. In an embodiment, the length H2 may be, for example, about 0.2 times to about 0.6 times the length H1. In an embodiment, the diameter DI may be, for example, about 75 μm to about 100 μm. In an embodiment, the width WD may be, for example, about 12.5 μm to about 15 μm. In an embodiment, the length L1 may be, for example, about 125 μm to about 150 μm. In an embodiment, the length L2 may be, for example, about 250 μm to about 275 μm.

[0100] In an embodiment, when the thickness of the base layer BS is about 100 μm, the length H1 may be, for example, about 500 μm or more. In an embodiment, the length H2 may be, for example, about 0.2 times to about 0.6 times the length H1. In an embodiment, the diameter DI may be, for example, about 30 μm to about 40 μm. In an embodiment, the width WD may be, for example, about 5 μm to about 6 μm. In an embodiment, the length L1 may be, for example, about 50 μm to about 60 μm. In an embodiment, the length L2 may be, for example, about 100 μm to about 110 μm.

[0101] In an embodiment, even when the thickness of the base layer BS changes, the width of the folding region 220F may be maintained at, for example, 5 millimeters (mm). Fig. 8A The length measured along the first direction DR1 is shown in .

[0102] Reference Figure 8B In order to improve the visibility of the display device, the third portion PT3' may have a curved shape. In an embodiment, the third portion PT3' may have a wave shape, for example. The third portion PT3' having a curved shape prevents the optical interference phenomenon caused by the groove HM', thereby improving the visibility of the folding area 220F defined by the groove HM'. Figure 5 , Figure 6 , Figure 7 and Fig. 8A The same description described in can be applied to the groove HM'.

[0103] Fig.9A and Fig. 9B It is shown Figure 5 An enlarged view of an embodiment of area AA is shown in FIG. Fig.9A and Fig. 9B Show area AA'' as Figure 5 An embodiment of region AA is shown in FIG.

[0104] In an embodiment, when Fig.9A The compressive force is applied to the window 220 (see Figure 5), the third portion PT3 of the groove HM may have the first width W1. The resin RS disposed in the groove HM may absorb the compressive force applied to the window 220.

[0105] In an embodiment, when Fig. 9B As shown in FIG. 2 , a tensile force is applied to the window 220 (see FIG. Figure 5 ), the third portion PT3" of the groove HM" has a first width W1 and a second width W2. The second width W2 may be a width measured at the center of the third portion PT3". The first width W1 may be a width of an end portion of the third portion PT3" adjacent to the first portion PT1 or the second portion PT2. The first width W1 and Fig.9A The first width W1 of the third portion PT3 shown in the figure is substantially the same. In an embodiment, the second width W2 is greater than the first width W1. That is, the width of the third portion PT3" may decrease from the center of the third portion PT3" toward the first portion PT1 and the second portion PT2. The resin RS disposed in the groove HM" may absorb the tensile force applied to the window 220.

[0106] Reference Fig.9A and Fig. 9B , when the resin RS having elastic force is disposed in the groove HM, the window 220 can ensure the flow space by the difference (W2-W1) between the second width W2 and the first width W1. In addition, the flow space can be ensured by adjusting the number of grooves HM. In the display device 1000 in the embodiment, the flow space in the window 220 can be ensured by a plurality of grooves HM defined in the window 220 and the resin RS disposed in the plurality of grooves HM, thereby preventing the window 220 from being deformed by the compression force or the tension force generated when the display device 1000 is folded.

[0107] Fig.10 is an enlarged plan view showing an embodiment of a portion of a base layer BS according to the present invention. Fig.11 An embodiment of the resin RS according to the present invention is schematically shown.

[0108] Fig.10 The base layer BS (refer to Figure 7 ) of the enlarged folding area 220F. The first peripheral area NCA1, the central area CA, and the second peripheral area NCA2 may be sequentially defined in the folding area 220F along the first direction DR1. That is, the central area CA may be defined between the first peripheral area NCA1 and the second peripheral area NCA2.

[0109] The central area CA is a central portion of the folding area 220F, and may be an area defining a folding axis FX of the base layer BS in the folding area 220F. The base layer BS may be folded inwardly or outwardly along the folding axis FX.

[0110] The first peripheral area NCA1 and the second peripheral area NCA2 may be respectively the central area CA and the first non-folding area 220NF1 and the second non-folding area 220NF2 (refer to Figure 7 ) between the two.

[0111] like Fig.10 As shown in FIG. 1 , in an embodiment, a first groove HM1 defined in the central area CA and a second groove HM2 and a third groove HM3 defined in the first peripheral area NCA1 may be defined in the base layer BS. The second groove HM2 may be adjacent to the central area CA, and the third groove HM3 may be adjacent to the first non-folding area 220NF1 (refer to FIG. 1 ). Figure 7 That is, the second groove HM2 may be defined between the first groove HM1 and the third groove HM3.

[0112] Because the central area CA has a greater stress than the peripheral area NCA due to folding, along the first direction DR1, the length of the first gap P1 may be smaller than the length of the second gap P2, wherein the first gap P1 is the gap between the first groove HM1 and the second groove HM2, and the second gap P2 is the gap between the second groove HM2 and the third groove HM3. That is, the length of the gap between the grooves HM set in the central area CA may be smaller than the length of the gap between the grooves HM set in the peripheral area NCA. When the length of the gap between the grooves HM increases from the central area CA to the peripheral area NCA, the visibility of the display device 1000 may be improved. The present invention is not limited to this. In one embodiment, the length of the first gap P1 may be equal to the length of the second gap P2.

[0113] Fig.11 An embodiment of the resin RS according to the present invention is schematically shown. In an embodiment, the resin RS comprises or consists of a polymer comprising a thiol group (—SH).

[0114] Refer to Figure 6 , Figure 7 and Fig.11 , the resin RS fills each of the grooves HM defined in the folding region 220F of the base layer BS.

[0115] Since the resin RS is provided in the folding area 220F (refer to Figure 7 ), so it can meet the window 220 (refer to Figure 5 ) The resin RS of the present invention is selected within the range of folding and translucent properties.

[0116] To satisfy the folding property of the window 220, the resin RS may have a predetermined elastic force. In an embodiment, the resin RS may be an elastomer. Specifically, the resin RS may be, for example, a material based on polydimethylsiloxane ("PDMS"). When the window 220 is folded, the PDMS-based resin RS may absorb the applied compressive stress or tensile stress.

[0117] Since the resin RS disposed in the folding region 220F has a predetermined elastic force, the resin RS may absorb stress caused by folding to prevent deformation of the window 220. Therefore, the occurrence of creases caused when the window 220 is folded multiple times may be reduced.

[0118] The resin RS may be a semi-transparent material. To improve the semi-transparent property of the window 220 including two or more materials, the difference between the refractive index of the resin RS and the refractive index of the base layer BS may be, for example, less than 0.1. Preferably, the refractive index of the resin RS and the refractive index of the base layer BS may be adjusted to be substantially the same.

[0119] In an embodiment, when the base layer BS is a glass substrate, the refractive index of the resin RS may be, for example, about 1.5 to about 1.6. Specifically, the refractive index of the resin RS may be, for example, about 1.5 to about 1.54. To obtain a refractive index of 1.5 or more, the resin RS may include a thiol group (-SH) or consist of a thiol group.

[0120] The resin RS in an embodiment of the present invention may include polydimethylsiloxanethiol to satisfy folding and translucent properties. In an embodiment, polydimethylsiloxanethiol is an elastomer and, for example, may have a refractive index of about 1.5 to about 1.54.

[0121] In addition, the level of crosslinking can be controlled by polymerizing the crosslinking agent with the resin RS for fine adjustment of the refractive index and elastic modulus. In an embodiment, the resin RS and the crosslinking agent including polydimethylsiloxane thiol can be polymerized to increase the thiol-ene crosslinking. The crosslinking agent may include at least one of a thiol-based crosslinking agent, a vinyl-based crosslinking agent, and an acrylic-based crosslinking agent. In an embodiment, the thiol-based crosslinking agent may include, for example, pentaerythritol tetra-3-mercaptopropionate ("PETMP"), the vinyl-based crosslinking agent may include α,ω vinyl-terminated PDMS, and the acrylic-based crosslinking agent may include pentaerythritol tetraacrylate, etc.

[0122] In the window 220 in the embodiment of the present invention, since the groove HM is defined in the folding region 220F of the base layer BS and the resin RS including a thiol group is provided in each of the grooves HM, both folding and visibility properties can be improved. Therefore, the display device 1000 (refer to Figure 1A) product reliability.

[0123] In an embodiment of the present invention, the folding property of the display device can be improved by providing a plurality of grooves in the window and a resin in each of the plurality of grooves. In addition, by adjusting the resin property, the plurality of grooves can be hidden from the outside.

[0124] Although the present invention has been described with reference to the preferred embodiments of the present invention, it will be understood that the present invention should not be limited to these preferred embodiments, but various changes and modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention. Therefore, the technical scope of the present invention is not intended to be limited to the contents set forth in the detailed description of this specification.

Claims

1. A display device, comprising: Display module; as well as A window is provided on the display module, wherein the window comprises: The base layer includes: a folding region having a plurality of grooves defined therein; and Non-folding area; and a resin disposed in each of the plurality of grooves and including a thiol group, Wherein, the difference between the refractive index of the base layer and the refractive index of the resin is less than 0.

1.

2. The display device according to claim 1, wherein: Each of the plurality of grooves comprises: The first part, having a circular shape; a second portion spaced apart from the first portion and having a circular shape; and The third part connects the first part and the second part.

3. The display device according to claim 2, wherein: The width of the third portion includes at least one of a first width and a second width greater than the first width.

4. The display device according to claim 1, wherein: The plurality of grooves include a first groove defined in a central area of ​​the folding area, a second groove defined in a peripheral area of ​​the folding area, and a third groove defined in the peripheral area and closer to the non-folding area than the second groove is to the non-folding area; and The length of the gap between the first groove and the second groove is equal to the length of the gap between the second groove and the third groove.

5. The display device according to claim 1, wherein: The plurality of grooves include a first groove defined in a central area of ​​the folding area, a second groove defined in a peripheral area of ​​the folding area, and a third groove defined in the peripheral area and closer to the non-folding area than the second groove is to the non-folding area; and A length of a gap between the first groove and the second groove is smaller than a length of a gap between the second groove and the third groove.

6. The display device according to claim 1, wherein: The resin has translucency.

7. The display device according to claim 1, wherein: The resin has elasticity.

8. The display device according to claim 1, wherein: The resin has a refractive index of 1.5 to 1.

6.

9. The display device according to claim 1, wherein: The resin includes polydimethylsiloxanethiol.

10. The display device according to claim 9, wherein: The resin includes at least one of a thiol-based cross-linking agent, an acrylic-based cross-linking agent, and a vinyl-based cross-linking agent polymerized with the polydimethylsiloxanethiol.

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