Display device, composition for adhesive layer, and electronic device

Abstract

A display device, a composition for an adhesive layer, and an electronic device are provided. The display device includes a display unit including a light emitting element, a low refractive pattern disposed on the display unit and including an opening overlapping the light emitting element in a thickness direction of the display unit, and a high refractive adhesive layer disposed on the low refractive pattern and the display unit and including inorganic particles. The high refractive adhesive layer includes 1 wt% to 3 wt% of inorganic particles based on a total weight of the high refractive adhesive layer.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2024-0051487, filed on April 17, 2024, in the Korean Intellectual Property Office (KIPO), the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to a display device. BACKGROUND

[0004] As the information society develops, the demand for display devices for displaying images has increased and diversified. For example, display devices have been applied to various electronic devices such as smart phones, digital cameras, laptop computers, navigation devices, and smart TVs. The display device can be a flat panel display device such as a liquid crystal display device, a field emission display device, or an organic light emitting display device.

[0005] Recently, foldable display devices have received much attention. Foldable display devices have the advantages of both smart phones and tablet PCs, as they can have good portability and a wide screen. SUMMARY

[0006] Aspects of the present disclosure provide a display device including an adhesive layer having flexibility and durability so as to be able to be applied to a foldable display device, and a composition for the adhesive layer.

[0007] However, aspects of the present disclosure are not limited to the aspects set forth herein. The above and other aspects of the present disclosure will become more apparent to one of ordinary skill in the art to which the present disclosure pertains by reading the detailed description of the present disclosure given below with reference to the accompanying drawings.

[0008] A display device according to an embodiment can include a display unit including a light emitting element, a low-refraction pattern disposed on the display unit and including an opening overlapping the light emitting element in a thickness direction of the display unit, and a high-refraction adhesive layer disposed on the low-refraction pattern and the display unit and including inorganic particles. The high-refraction adhesive layer can include 1 wt% to 3 wt% of the inorganic particles based on a total weight of the high-refraction adhesive layer.

[0009] According to an embodiment, the display device can further include a polarizing film disposed on the high-refraction adhesive layer.

[0010] According to an embodiment, the high-refraction adhesive layer can be in contact with the polarizing film.

[0011] According to an embodiment, the low-refractive pattern can have a refractive index in a range of about 1.45 to about 1.55, and the high-refractive adhesive layer can have a refractive index in a range of about 1.55 to about 1.65.

[0012] According to an embodiment, the inorganic particles can be at least one of zirconium oxide (ZrO2), titanium oxide (TiO2), aluminum oxide (Al2O3), and silicon oxide (SiO2).

[0013] According to an embodiment, the inorganic particles can be dispersed in the high-refractive adhesive layer.

[0014] According to an embodiment, the high-refractive adhesive layer can further include an aromatic monomer and an aliphatic monomer.

[0015] According to an embodiment, the aromatic monomer can include a first aromatic monomer and a second aromatic monomer different from each other.

[0016] According to an embodiment, the aliphatic monomer can include a first aliphatic monomer, a second aliphatic monomer, and a third aliphatic monomer different from each other.

[0017] According to an embodiment, the high-refractive adhesive layer can further include a xylene resin and a sulfurized aromatic compound.

[0018] According to an embodiment, the high-refractive adhesive layer can include about 40 wt% to about 80 wt% of the aromatic monomer, about 10 wt% to about 30 wt% of the aliphatic monomer, about 10 wt% to about 25 wt% of the xylene resin, about 10 wt% to about 20 wt% of the sulfurized aromatic compound, and about 1 wt% to about 3 wt% of the inorganic particles, based on the total weight of the high-refractive adhesive layer.

[0019] According to an embodiment, the high-refractive adhesive layer can have a storage modulus in a range of about 1.0 MPa to about 10 MPa at -20℃, the high-refractive adhesive layer can have a loss modulus in a range of about 3.5 MPa to about 10 MPa at -20℃, and the high-refractive adhesive layer can have a viscoelastic ratio in a range of about 2.9 to about 6 at -20℃.

[0020] According to an embodiment, the high-refractive adhesive layer can have a glass transition temperature in a range of about -30℃ to about -10℃.

[0021] According to an embodiment, the high-refractive adhesive layer can have a creep value in a range of about 10% to about 40% at 60℃.

[0022] According to an embodiment, the high-refractive adhesive layer can have a recovery value greater than or equal to about 70% at -20℃.

[0023] According to an embodiment, the display device can further include a touch sensor layer disposed between the display unit and the low-refraction pattern. The high-refraction adhesive layer can be in contact with the touch sensor layer and the polarizing film.

[0024] According to an embodiment, the low-refraction pattern can have a tapered shape in a cross-sectional view.

[0025] The composition for the adhesive layer according to an embodiment can include a first aromatic monomer and a second aromatic monomer different from each other, a first aliphatic monomer, a second aliphatic monomer, and a third aliphatic monomer different from each other, and inorganic particles including at least one of zirconium oxide (ZrO2), titanium oxide (TiO2), aluminum oxide (Al2O3), and silicon oxide (SiO2). The inorganic particles can be included in an amount of 1 wt% to 3 wt% based on the total weight of the composition for the adhesive layer.

[0026] According to an embodiment, the molecular weight of the first aromatic monomer can be less than the molecular weight of the second aromatic monomer, the content of the first aromatic monomer can be higher than the content of the second aromatic monomer, the molecular weight of the first aliphatic monomer can be greater than the molecular weight of the second aliphatic monomer and the molecular weight of the third aliphatic monomer, the molecular weight of the second aliphatic monomer can be greater than the molecular weight of the third aliphatic monomer, the content of the first aliphatic monomer can be higher than the content of the second aliphatic monomer and the content of the third aliphatic monomer, and the content of the second aliphatic monomer can be higher than the content of the third aliphatic monomer.

[0027] According to an embodiment, the composition for the adhesive layer can further include a xylene resin and a vulcanized aromatic compound.

[0028] According to an embodiment, an electronic device includes a display device including a display unit including a light emitting element, a low-refraction pattern disposed on the display unit and including an opening overlapping the light emitting element in a thickness direction of the display unit, and a high-refraction adhesive layer disposed on the low-refraction pattern and the display unit and including inorganic particles, wherein the high-refraction adhesive layer includes 1 wt% to 3 wt% of the inorganic particles based on the total weight of the high-refraction adhesive layer.

[0029] The details of other embodiments are described in the detailed description and illustrated in the drawings.

[0030] The display device according to an embodiment can not include a separate adhesive layer between the display panel and the front stack structure, and the display panel and the front stack structure can be bonded to each other by the high-refraction adhesive layer of the display panel. The high-refraction adhesive layer including a low content of inorganic particles can have excellent flexibility and durability in a foldable display device.

[0031] Effects of the present disclosure are not limited to the aforementioned effects, and various other effects include those described in the specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other aspects and features of the present disclosure will become more apparent by describing in detail embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0033] Figure 1 is a perspective view showing a deployed state of a display device according to an embodiment;

[0034] Figure 2 is a perspective view showing a folded state of a display device according to an embodiment;

[0035] Figure 3 is a perspective view showing a deployed state of a display device according to an embodiment;

[0036] Figure 4 is a perspective view showing a folded state of a display device according to an embodiment;

[0037] Figure 5 is based on Figure 1 An exploded perspective view of a display device according to an embodiment of the present invention;

[0038] Figure 6 It is along Figure 5 A schematic cross-sectional view of a display device according to an embodiment, taken along line II';

[0039] Figure 7 yes Figure 6 An enlarged schematic cross-sectional view of region A;

[0040] Figure 8 is a plan view showing a touch sensor layer of a display device according to an embodiment;

[0041] Figure 9 It is along Figure 8 A schematic cross-sectional view of a display device according to an embodiment, taken along line II-II'; and

[0042] Figure 10 yes Figure 9 An enlarged schematic cross-sectional view of region B. DETAILED DESCRIPTION

[0043] The advantages and features of the present disclosure and the methods for achieving the advantages and features will become apparent through the embodiments described in detail later with reference to the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and can be implemented in various forms. These embodiments are provided only to make the present disclosure complete and allow those skilled in the art to fully appreciate the scope of the present disclosure. The present disclosure will be defined by the scope of the claims.

[0044] When an element or layer is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it can be directly on, connected, or coupled to the other element or layer, or one or more intervening elements or layers can be present. In contrast, when an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. In this context, the term “connected” can refer to physical, electrical, and / or fluidic connection with or without intervening components. Further, when an element is referred to as being “in contact with” or “in contact” another element, the element can be in “electrical contact” or “physical contact” with the other element; or in “indirect contact” or “direct contact” with the other element. Throughout the specification, like components will be designated by like reference numerals. The shapes, sizes, proportions, angles, numbers, and so forth, of the shapes disclosed in the drawings for describing the embodiments are illustrative and, as such, the present disclosure is not limited to those shown in the drawings.

[0045] The terms “first,” “second,” and the like are used to describe various components, but the components are not limited by these terms. The terms are used only to distinguish one component from another. Accordingly, the first component mentioned below can be the second component within the technical spirit of the present disclosure.

[0046] “About” or “approximately” as used herein includes the recited value and means within an acceptable range of deviation for a particular value as determined by one of ordinary skill in the art. For example, “about” can mean within one or more standard deviations, or within ±30%, ±20%, ±10%, ±5% of the recited value.

[0047] In the specification and claims, the phrase “at least one of” is intended to include the meaning of “at least one selected from the group consisting of.” For example, “at least one of A and B” can be understood as using a meaning of “A, B, or A and B.” In the specification and claims, the term “and / or” is intended to include any combination of the terms “and” and “or.” For example, “A and / or B” can be understood as using a meaning of “A, B, or A and B.” The terms “and” and “or” can be used in a conjunctive or disjunctive sense and can be understood to be equivalent to “and / or.”

[0048] Unless otherwise defined or implied herein, all terms used are to be given their ordinary meaning as understood by one of ordinary skill in the art to which this disclosure pertains. It will also be appreciated that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless clearly defined in the specification.

[0049] Hereinafter, specific embodiments will be described with reference to the accompanying drawings.

[0050] Figure 1 and Figure 2 is a perspective view illustrating a display device 10 according to an embodiment. Figure 1 is a perspective view illustrating an unfolded state of a display device 10 according to an embodiment. Figure 2 is a perspective view illustrating a folded state of a display device 10 according to an embodiment.

[0051] In Figure 1 and Figure 2 , the first direction (X-axis direction) can be a direction parallel to one side of the display device 10 in a plan view, and can be, for example, a landscape direction of the display device 10. The second direction (Y-axis direction) can be a direction parallel to another side of the display device 10 in contact with the one side of the display device 10 in a plan view, and can be a portrait direction of the display device 10. The third direction (Z-axis direction) can be a thickness direction of the display device 10.

[0052] The display device 10 can be used in an electronic device. The electronic device including the display device 10 can include a display screen of a portable electronic device such as a mobile phone, a smart phone, a tablet PC, a smart watch, a watch phone, a mobile communication terminal, an electronic organizer, an electronic book, a portable multimedia player (PMP), a navigation device, and an ultra-mobile PC (UMPC), a television, a notebook computer, a monitor, a billboard, and an Internet of Things (IoT) device. Those listed above are only as examples, and the display device 10 can also be employed in other electronic devices.

[0053] The display device 10 can have a rectangular or square shape in a plan view. The display device 10 can have a rectangular shape including perpendicular corners or a rectangular shape including rounded corners in a plan view. The display device 10 can include two short sides extending in the first direction (X-axis direction) and two long sides extending in the second direction (Y-axis direction) in a plan view.

[0054] The display device 10 can include a display area DA and a non-display area NDA. In a plan view, the shape of the display area DA can correspond to the shape of the display device 10. For example, in the case where the display device 10 has a rectangular shape in a plan view, the display area DA can also have a rectangular shape.

[0055] The display area DA can be an area that displays an image by including a plurality of pixels. The pixels can be arranged in a matrix direction. The pixels can have a rectangular shape, a diamond shape, or a square shape in a plan view, but are not limited thereto. For example, the pixels can have other quadrilateral shapes other than a rectangular shape, a diamond shape, or a square shape, other polygonal shapes other than a quadrilateral shape, a circular shape, or an elliptical shape in a plan view.

[0056] The non-display area NDA can be an area that does not display an image because it does not include pixels. The non-display area NDA can be arranged adjacent to the display area DA. As Figure 1 and Figure 2 As shown in FIGS. 1A and 1B, the non-display area NDA can surround the display area DA, but is not limited thereto. In another embodiment, the display area DA can be partially surrounded by the non-display area NDA.

[0057] The display device 10 can be maintained in a folded state or an unfolded state. As shown in Figure 2 The display device 10 can be folded in an inner folding manner in which the display area DA is arranged inside. In the case where the display device 10 is folded in the inner folding manner, the front surfaces of the display device 10 can face each other. In another embodiment, the display device 10 can be folded in an outer folding manner in which the display area DA is arranged outside. In the case where the display device 10 is folded in the outer folding manner, the rear surfaces of the display device 10 can face each other.

[0058] The display device 10 can include a folding area FDA, a first non-folding area NFA1, and a second non-folding area NFA2. The folding area FDA can be an area in which the display device 10 is bendable or foldable, and the first non-folding area NFA1 and the second non-folding area NFA2 can be areas in which the display device 10 is not bendable or foldable.

[0059] The first non-folding area NFA1 can be arranged on one side (for example, an upper side) of the folding area FDA. The second non-folding area NFA2 can be arranged on the other side (for example, a lower side) of the folding area FDA. The folding area FDA can be an area defined by a first folding line FL1 and a second folding line FL2, and can be an area that is bendable with a curvature. The first folding line FL1 can be a boundary between the folding area FDA and the first non-folding area NFA1, and the second folding line FL2 can be a boundary between the folding area FDA and the second non-folding area NFA2.

[0060] like Figure 1 and Figure 2 As shown in FIG, the first folding line FL1 and the second folding line FL2 may extend in a first direction (X-axis direction), and the display device 10 may be foldable about a second direction (Y-axis direction). For this reason, the length of the display device 10 in the second direction (Y-axis direction) may be reduced by approximately half, and thus, the user may conveniently carry the display device 10.

[0061] The first folding line FL1 and the second folding line FL2 are as follows Figure 1 and Figure 2 In the case where the fold area FDA extends in the first direction (X-axis direction) as shown in FIG, the length of the fold area FDA in the second direction (Y-axis direction) may be smaller than the length of the fold area FDA in the first direction (X-axis direction). The length of the first non-folding area NFA1 in the second direction (Y-axis direction) may be larger than the length of the first non-folding area NFA1 in the first direction (X-axis direction). The length of the second non-folding area NFA2 in the second direction (Y-axis direction) may be larger than the length of the second non-folding area NFA2 in the first direction (X-axis direction).

[0062] In a plan view, each of the display area DA and the non-display area NDA may overlap with at least one of the folding area FDA, the first non-folding area NFA1, and the second non-folding area NFA2. Figure 1 and Figure 2 , it is shown that each of the display area DA and the non-display area NDA overlaps with the folding area FDA, the first non-folding area NFA1, and the second non-folding area NFA2 in a plan view.

[0063] Figure 3 and Figure 4 is a perspective view showing a display device 10_1 according to an embodiment. Figure 3 is a perspective view illustrating a deployed state of the display device 10_1 according to the embodiment. Figure 4 is a perspective view illustrating a folded state of the display device 10_1 according to the embodiment.

[0064] Figure 3 and Figure 4 The implementation method and Figure 1 and Figure 2 The embodiment of the present invention may be different in at least that the first folding line FL1 and the second folding line FL2 may extend in the second direction (Y-axis direction), and the display device 10_1 may be foldable in the first direction (X-axis direction), and therefore, the length of the display device 10_1 in the first direction (X-axis direction) may be reduced by approximately half, and accordingly, the user may conveniently carry the display device 10_1. Therefore, the description of Figure 3 andFigure 4 of the display device 10 according to embodiments.

[0065] Figure 5 is a perspective view of a display device 10 according to embodiments. Figure 1 is an exploded perspective view of a display device 10 according to embodiments. Figure 6 is a schematic cross-sectional view of a display device according to embodiments taken along line I-I' of Figure 5 Figure 7 is a magnified view of area A of Figure 6

[0066] Referring to Figure 5 and Figure 6 , the display device 10 can include a display panel 100, a front stack structure 200 stacked in front of the display panel 100, and a rear stack structure 300 stacked behind the display panel 100. The front of the display panel 100 can be a direction in which the display panel 100 displays a picture, and the rear of the display panel 100 can be a direction opposite to the front of the display panel 100. A surface of the display panel 100 can be positioned at the front, and another surface of the display panel 100 can be positioned at the rear.

[0067] The front stack structure 200 can include a polarizing film 210, a window 220, and a protective film 230, and the rear stack structure 300 can include a panel under member 310, a light blocking member 320, a digital converter layer 330, a shielding member 340, a heat dissipation member 350, and a buffer member 360.

[0068] The front stack structure 200 can further include a first adhesive member AD1 disposed between the polarizing film 210 and the window 220, and a second adhesive member AD2 disposed between the window 220 and the protective film 230. The rear stack structure 300 can further include a third adhesive member AD3 disposed between the display panel 100 and the panel under member 310, a fourth adhesive member AD4 disposed between the panel under member 310 and the light blocking member 320, and a fifth adhesive member AD5 disposed between the buffer member 360 and the digital converter layer 330.

[0069] Examples of a display panel displaying an image can include an organic light emitting display panel using an organic light emitting diode, a quantum dot light emitting display panel including a quantum dot light emitting layer, an inorganic light emitting display panel including an inorganic semiconductor, and a micro light emitting display panel using a micro light emitting diode (micro-LED). Hereinafter, it will be described that the display panel 100 is an organic light emitting display panel according to embodiments, but the present disclosure is not limited thereto. The display panel 100 will be described in detail later with reference to Figure 9

[0070] ​​​The polarizing film 210 can be disposed on a front surface of the display panel 100. The polarizing film 210 can be attached to the front surface of the display panel 100 by a high-refractive adhesive layer 402 (see FIG. 2) of the display panel 100 to be described below. The polarizing film 210 can include a linear polarizing plate and a phase retardation film such as a λ / 4 plate (quarter wave plate). Figure 9

[0071] The window 220 can be disposed on a front surface of the polarizing film 210. The window 220 can be attached to the front surface of the polarizing film 210 by a first adhesive member AD1. The window 220 can be made of a transparent material, and can include, for example, glass or plastic. For example, the window 220 can be an ultra-thin glass (UTG) or a transparent polyimide film having a thickness less than or equal to about 0.1 mm, but is not limited thereto.

[0072] The protective film 230 can be disposed on a front surface of the window 220. The protective film 230 can be attached to the front surface of the window 220 by a second adhesive member AD2. The protective film 230 can perform at least one of a splash-proof function, an impact-absorbing function, an anti-scratching function, an anti-fingerprint function, and an anti-glare function of the window 220.

[0073] The first adhesive member AD1 and the second adhesive member AD2 can be the same as or different from each other, and can each be a transparent pressure sensitive adhesive (PSA), an optical clear adhesive (OCA) film, or an optical clear resin (OCR).

[0074] The panel-down member 310 can be disposed on a rear surface of the display panel 100. The panel-down member 310 can be attached to the rear surface of the display panel 100 by a third adhesive member AD3. The third adhesive member AD3 can be a pressure sensitive adhesive (PSA). The panel-down member 310 can be a cushion layer for absorbing an external impact. The panel-down member 310 can absorb an external impact to prevent the display panel 100 from being damaged. The panel-down member 310 can be formed as a single layer or multiple layers. For example, the panel-down member 310 can include an elastic material such as a sponge formed by foaming molding of rubber, urethane-based material, or acrylic material.

[0075] Figure 5 and Figure 6 It is shown in FIGS. 1, 2, and 3 that the panel-down member 310 is disposed in the folding area FDA, but the present disclosure is not limited thereto. For example, a portion of the panel-down member 310 in the folding area FDA can be removed to make the display device 10 easily foldable.

[0076] ​The light blocking member 320 can be disposed on the rear surface of the panel lower member 310. The light blocking member 320 can be attached to the rear surface of the panel lower member 310 by a fourth adhesive member AD4. The fourth adhesive member AD4 can not be disposed in the folding area FDA so as to reduce the folding stress of the display device 10. For example, a plurality of fourth adhesive members AD4 can be provided, one of the fourth adhesive members AD4 can be disposed in the first non-folding area NFA1, and another of the fourth adhesive members AD4 can be disposed in the second non-folding area NFA2. The fourth adhesive members AD4 can each be a pressure sensitive adhesive.

[0077] The light blocking member 320 can include a polymer including carbon fibers or glass fibers. In the case where the light blocking member 320 includes carbon fibers, the polymer can be an epoxy resin, a polyester, a polyamide, a polycarbonate, a polypropylene, a polybutylene, or a vinyl ester. In the case where the light blocking member 320 includes glass fibers, the polymer can be an epoxy resin, a polyester, a polyamide, or a vinyl ester.

[0078] The thickness of the light blocking member 320 can be greater than the thickness of the digitizer layer 330 or the thickness of the shield member 340. The thickness of the light blocking member 320 can be greater than the thickness of the display panel 100.

[0079] The light blocking member 320 can include a plurality of strips disposed in the folding area FDA so as to be easily bendable in the folding area FDA. The extension direction of each of the strips, the extension direction of the first folding line FL1 (see Figure 1 ), and the extension direction of the second folding line FL2 (see Figure 1 ) can be substantially parallel to each other. For example, each of the strips can extend in a first direction (X-axis direction). The strips can be arranged in a second direction (Y-axis direction). A slit can be formed between strips adjacent to each other among the strips. The width of each of the strips can be less than the width of each of the slits.

[0080] The buffer member 360 can be disposed on the rear surface of the light blocking member 320. The buffer member 360 can absorb an external impact to prevent the light blocking member 320 and the digitizer layer 330 from being damaged. The buffer member 360 can include an elastic material such as a sponge formed by foaming molding of rubber, urethane-based material, or acrylic material.

[0081] The digitizer layer 330 can include a first digitizer layer 331 and a second digitizer layer 332. The first digitizer layer 331 and the second digitizer layer 332 can be disposed on the rear surface of the buffer member 360. The first digitizer layer 331 and the second digitizer layer 332 can be attached to the rear surface of the buffer member 360 by a fifth adhesive member AD5. The fifth adhesive members AD5 can each be a pressure sensitive adhesive.

[0082] The first digital converter layer 331, the second digital converter layer 332, and the fifth adhesive member AD5 can not be disposed in at least a portion of the folding area FDA so as to reduce a folding stress of the display device 10. For example, one of the fifth adhesive members AD5 and the first digital converter layer 331 can be disposed in the first non-folding area NFA1, and the other of the fifth adhesive members AD5 and the second digital converter layer 332 can be disposed in the second non-folding area NFA2. A gap between the first digital converter layer 331 and the second digital converter layer 332 can overlap the folding area FDA in the thickness direction (Z-axis direction), and can be less than a width of the folding area FDA. The width of the folding area FDA can be a length of the folding area FDA in the second direction (Y-axis direction).

[0083] The first digital converter layer 331 and the second digital converter layer 332 can include an electrode pattern for sensing proximity or contact of an electronic pen supporting electromagnetic induction (EMR), such as a stylus pen. The first digital converter layer 331 and the second digital converter layer 332 can sense a magnetic field or an electromagnetic signal emitted from the electronic pen through the electrode pattern, and determine a point at which the sensed magnetic field or electromagnetic signal is greatest as a touch coordinate.

[0084] The shielding member 340 can include a first shielding member 341 and a second shielding member 342. The first shielding member 341 and the second shielding member 342 can be disposed on a rear surface of the digital converter layer 330.

[0085] The first shielding member 341 and the second shielding member 342 can not be disposed in at least a portion of the folding area FDA so as to reduce a folding stress of the display device 10. For example, the first shielding member 341 can be disposed in the first non-folding area NFA1, and the second shielding member 342 can be disposed in the second non-folding area NFA2. A gap between the first shielding member 341 and the second shielding member 342 can overlap the folding area FDA in the thickness direction (Z-axis direction), and can be less than a width of the folding area FDA.

[0086] The first shielding member 341 and the second shielding member 342 can include a magnetic metal powder, and thus a magnetic field or an electromagnetic signal passing through the digital converter layer 330 can flow into the first shielding member 341 and the second shielding member 342. The first shielding member 341 and the second shielding member 342 can reduce the magnetic field or the electromagnetic signal emitted to a rear surface of the first shielding member 341 and the second shielding member 342.

[0087] The heat dissipation member 350 can include a first heat dissipation member 351 and a second heat dissipation member 352. The first heat dissipation member 351 and the second heat dissipation member 352 can be disposed on a rear surface of the shielding member 340.

[0088] The first heat dissipation member 351 and the second heat dissipation member 352 may not be arranged in at least a portion of the folding area FDA in order to reduce the folding stress of the display device 10. For example, the first heat dissipation member 351 may be arranged in the first non-folding area NFA1, and the second heat dissipation member 352 may be arranged in the second non-folding area NFA2. The gap between the first heat dissipation member 351 and the second heat dissipation member 352 may overlap with the folding area FDA in the thickness direction (Z-axis direction) and may be smaller than the width of the folding area FDA.

[0089] The first and second heat dissipation members 351 and 352 may each be a metal film made of a metal having excellent thermal conductivity, such as copper, nickel, ferrite, or silver. For this reason, heat generated in the display device 10 can be dissipated to the outside through the first and second heat dissipation members 351 and 352.

[0090] like Figure 6 As shown in , the light blocking member 320 may be disposed on the digitizer layer 330 and the shielding member 340 , and thus can prevent steps of the electrode pattern of the digitizer layer 330 or magnetic metal powder of the shielding member 340 from being observed by the user on the front surface of the display device 10 .

[0091] Figure 7 yes Figure 6 1 is an enlarged schematic cross-sectional view of a region A of FIG. 1 , and schematically illustrates the display panel 100 and the polarizing film 210 .

[0092] Reference Figure 7 The display panel 100 may include a display unit DU and a touch sensing unit TDU. The display unit DU includes a substrate SUB1 and a thin film transistor layer TFTL, a light emitting element layer EML and an encapsulation layer TFEL arranged on the substrate SUB1. The touch sensing unit TDU includes a touch sensor layer TSL and a total reflection layer TRL.

[0093] The substrate SUB1 may be made of an insulating material such as glass, quartz, or a polymer resin. For example, the substrate SUB1 may include a polymer resin such as polyethersulfone (PES), polyacrylate (PA), polyarylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyallylate, polyimide (PI), polycarbonate (PC), cellulose triacetate (CAT), cellulose acetate propionate (CAP), or a combination thereof. In another embodiment, the substrate SUB1 may include a metal.

[0094] The substrate SUB1 can be a flexible substrate that can be bent, folded, and / or rolled. The substrate SUB1 can be made of polyimide (PI), but is not limited thereto.

[0095] The thin film transistor layer TFTL can be disposed on the substrate SUB1. In the thin film transistor layer TFTL, a scan line, a data line, a power line, a scan control line, a wiring connecting a pad and a data line to each other, and the like, and a thin film transistor of each of the pixels can be formed. Each of the thin film transistors can include a gate electrode, a semiconductor layer, a source electrode, and a drain electrode.

[0096] The thin film transistor layer TFTL can be disposed in the display area DA and the non-display area NDA (see Figure 1 ). For example, the thin film transistor of each of the pixels of the thin film transistor layer TFTL, the scan line, the data line, and the power line can be disposed in the display area DA. For example, the scan control line and the link line of the thin film transistor layer TFTL can be disposed in the non-display area NDA.

[0097] The light emitting element layer EML can be disposed on the thin film transistor layer TFTL. The light emitting element layer EML can include light emitting elements each including a first electrode, a light emitting layer, and a second electrode of the pixels, and a pixel defining layer defining the pixels. The light emitting layer can be an organic light emitting layer including an organic material, and the light emitting layer can include a hole transport layer, an organic light emitting layer, and an electron transport layer. In a case where a voltage is applied to the first electrode and a cathode voltage is applied to the second electrode through the thin film transistor of the thin film transistor layer TFTL, holes and electrons can move to the organic light emitting layer through the hole transport layer and the electron transport layer, respectively, and can recombine with each other in the organic light emitting layer to emit light. The light emitting elements of the pixels of the light emitting element layer EML can be disposed in the display area DA.

[0098] The encapsulation layer TFEL can be disposed on the light emitting element layer EML. The encapsulation layer TFEL can be used to prevent oxygen or moisture from penetrating into the light emitting element layer EML. The encapsulation layer TFEL can be used to protect the light emitting element layer EML from foreign substances such as dust.

[0099] The encapsulation layer TFEL can be disposed in both the display area DA and the non-display area NDA. For example, the encapsulation layer TFEL can cover the light emitting element layer EML of the display area DA and the non-display area NDA, and cover the thin film transistor layer TFTL of the non-display area NDA.

[0100] The touch sensor layer TSL can be disposed on the encapsulation layer TFEL. Since the touch sensor layer TSL can be directly disposed on the encapsulation layer TFEL, the thickness of the display apparatus 10 can be reduced compared to a case where a separate touch panel including the touch sensor layer TSL is attached on the encapsulation layer TFEL.

[0101] The touch sensor layer TSL can include touch electrodes for capacitively sensing a touch of a user and touch lines connecting pads and the touch electrodes to each other. For example, the touch sensor layer TSL can sense a touch of a user in a self-capacitive manner or in a mutual-capacitive manner.

[0102] The touch electrodes of the touch sensor layer TSL can be disposed in the display area DA. The touch lines of the touch sensor layer TSL can be disposed in a touch peripheral area overlapping the non-display area NDA in a thickness direction of the touch sensor layer TSL.

[0103] The total reflection layer TRL can be disposed on the touch sensor layer TSL. The total reflection layer TRL can be a layer that totally reflects light, among the light of the light emitting element layer EML, propagating in a side surface direction of the display panel 100, rather than in an upward direction (Z-axis direction) of the display panel 100, so that the light propagating in the side surface direction of the display panel 100 can propagate in the upward direction of the display panel 100, and a layer that adheres the polarizing film 210 disposed on the total reflection layer TRL and the display panel 100 to each other.

[0104] Figure 8 is a plan view illustrating a touch sensor layer of a display device according to an embodiment. In Figure 8 , for convenience of explanation, the light emitting portions EA1, EA2, EA3, and EA4 of the pixel PX and the drive electrodes TE, the connection portions BE1 and BE2, the sense electrodes RE, and the touch contact hole TCNT1 of the touch sensor layer TSL (see Figure 9 ) are illustrated.

[0105] The touch sensor layer TSL can include two types of electrodes, such as the drive electrodes TE and the sense electrodes RE. The touch sensor layer TRL can be driven in a mutual-capacitive manner by sensing, through the sense electrodes RE, an amount of charge variation of mutual capacitance of each of a plurality of touch nodes after a touch driving signal is applied to the drive electrodes TE.

[0106] The plurality of drive electrodes TE can be disposed to be spaced apart from each other in the second direction (Y-axis direction), and the plurality of sense electrodes RE can be disposed to be spaced apart from each other in the second direction (Y-axis direction). The drive electrodes TE and the sense electrodes RE can be disposed at the same layer and spaced apart from each other. For example, a gap can be formed between the drive electrodes TE and the sense electrodes RE adjacent to each other.

[0107] As illustrated in Figure 8 , the drive electrodes TE adjacent to each other in the second direction (Y-axis direction) can be connected to each other through the first connection portions BE1. As illustrated in Figure 8 , the sense electrodes RE adjacent to each other in the first direction (X-axis direction) can be connected to each other through the second connection portions BE2.

[0108] A plurality of first connection portions BE1 can be formed, and the first connection portions BE1, the driving electrodes TE, and the sensing electrodes RE can be disposed at different layers. The first connection portions BE1 can be bent at least once. Figure 8 The first connection portions BE1 are shown to have a clip (“<” or “>”) shape in a plan view in, but the shape of the first connection portions BE1 in a plan view is not limited thereto. Since the driving electrodes TE adjacent to each other in the second direction (Y-axis direction) are connected to each other by the plurality of first connection portions BE1, even if one of the first connection portions BE1 is disconnected, the connection between the driving electrodes TE adjacent to each other in the second direction (Y-axis direction) can be maintained. Figure 8 The driving electrodes TE adjacent to each other are shown to be connected to each other by two first connection portions BE1 in, but the number of the first connection portions BE1 is not limited thereto.

[0109] Each of the first connection portions BE1 can overlap the driving electrodes TE adjacent to each other in the second direction (Y-axis direction) in a third direction (Z-axis direction) that is a thickness direction of the substrate SUB1 (see Figure 9 ). Each of the first connection portions BE1 can overlap the sensing electrodes RE in the third direction (Z-axis direction). One side of the first connection portion BE1 can be connected to one of the driving electrodes TE adjacent to each other in the second direction (Y-axis direction) through the touch contact hole TCNT1. The other side of the first connection portion BE1 can be connected to the other of the driving electrodes TE adjacent to each other in the second direction (Y-axis direction) through the touch contact hole TCNT1.

[0110] Due to the first connection portions BE1, the driving electrodes TE and the sensing electrodes RE can be electrically disconnected from each other at each of the intersection portions between the driving electrodes TE and the sensing electrodes RE. For this reason, mutual capacitances can be formed at each of the intersection portions between the driving electrodes TE and the sensing electrodes RE.

[0111] Each of the driving electrodes TE, the sensing electrodes RE, and the first connection portions BE1 can have a mesh shape or a net shape in a plan view. For this reason, each of the driving electrodes TE, the sensing electrodes RE, and the first connection portions BE1 can not overlap the plurality of light emitting portions EA1, EA2, EA3, and EA4 of each of the pixels PX. Accordingly, a phenomenon in which light emitted from the light emitting portions EA1, EA2, EA3, and EA4 is blocked by the driving electrodes TE, the sensing electrodes RE, and the first connection portions BE1 can be prevented and the brightness of the light can not be reduced.

[0112] Each of the pixels PX can include a first light emitting part EA1 emitting light of a first color, a second light emitting part EA2 emitting light of a second color, a third light emitting part EA3 emitting light of a third color, and a fourth light emitting part EA4 emitting light of the second color. For example, the first color can be red, the second color can be green, and the third color can be blue.

[0113] The first light emitting part EA1 and the second light emitting part EA2 of each of the pixels PX can be adjacent to each other in the fourth direction DR2, and the third light emitting part EA3 and the fourth light emitting part EA4 of each of the pixels PX can be adjacent to each other in the fourth direction DR2. The first light emitting part EA1 and the fourth light emitting part EA4 of each of the pixels PX can be adjacent to each other in the fifth direction DR1, and the second light emitting part EA2 and the third light emitting part EA3 of each of the pixels PX can be adjacent to each other in the fifth direction DR1.

[0114] Each of the first light emitting part EA1, the second light emitting part EA2, the third light emitting part EA3, and the fourth light emitting part EA4 can have a rhombus shape or a rectangular shape in a plan view, but is not limited thereto. In another embodiment, each of the first light emitting part EA1, the second light emitting part EA2, the third light emitting part EA3, and the fourth light emitting part EA4 can have a polygonal shape other than a quadrilateral shape, a circular shape, or an elliptical shape in a plan view. Figure 8 It is illustrated in FIG. 3 that the third light emitting part EA3 has the largest area and the second light emitting part EA2 and the fourth light emitting part EA4 have the smallest area, but the disclosure is not limited thereto.

[0115] The second light emitting part EA2 and the fourth light emitting part EA4 can be arranged in odd-numbered rows. The second light emitting part EA2 and the fourth light emitting part EA4 can be arranged side by side in the first direction (X-axis direction) in each of the odd-numbered rows. The second light emitting part EA2 and the fourth light emitting part EA4 can be alternately arranged in each of the odd-numbered rows. Each of the second light emitting parts EA2 can have a long side in the fourth direction DR2 and a short side in the fifth direction DR1, and each of the fourth light emitting parts EA4 can have a short side in the fourth direction DR2 and a long side in the fifth direction DR1. The fourth direction DR2 can be a direction between the first direction (X-axis direction) and the second direction (Y-axis direction), and can be a direction inclined by 45° with respect to the first direction (X-axis direction). The fifth direction DR1 can be a direction perpendicular to the fourth direction DR2.

[0116] The first light emitting parts EA1 and the third light emitting parts EA3 can be arranged in even rows. The first light emitting parts EA1 and the third light emitting parts EA3 can be arranged side by side in the first direction (X-axis direction) in each of the even rows. The first light emitting parts EA1 and the third light emitting parts EA3 can be alternately arranged in each of the even rows.

[0117] The second light emitting parts EA2 and the fourth light emitting parts EA4 can be arranged in odd columns. The second light emitting parts EA2 and the fourth light emitting parts EA4 can be arranged side by side in the second direction (Y-axis direction) in each of the odd columns. The second light emitting parts EA2 and the fourth light emitting parts EA4 can be alternately arranged in each of the odd columns.

[0118] The first light emitting parts EA1 and the third light emitting parts EA3 can be arranged in even columns. The first light emitting parts EA1 and the third light emitting parts EA3 can be arranged side by side in the second direction (Y-axis direction) in each of the even columns. The first light emitting parts EA1 and the third light emitting parts EA3 can be alternately arranged in each of the even columns.

[0119] Figure 9 is a schematic cross-sectional view of a display device according to an embodiment taken along line II-II' of Figure 8

[0120] Referring to Figure 9 The barrier film BR can be arranged on the substrate SUB1. The substrate SUB1 can be made of an insulating material such as a polymer resin. For example, the substrate SUB1 can be made of polyimide. The substrate SUB1 can be a flexible substrate that can be bent, folded, and / or rolled.

[0121] The barrier film BR can be a film for protecting the transistors of the thin film transistor layer TFTL and the light emitting layer 172 of the light emitting element layer EML from moisture penetration through the substrate SUB1 that is susceptible to moisture penetration. The barrier film BR can include a plurality of inorganic films stacked alternately with each other. For example, the barrier film BR can be formed as a plurality of films in which one or more inorganic films among a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, and an aluminum oxide layer are stacked alternately with each other.

[0122] The thin film transistors ST1 can be arranged on the barrier film BR. Each of the thin film transistors ST1 can include an active layer ACT1, a gate electrode G1, a source electrode S1, and a drain electrode D1.

[0123] ​The active layer ACT1, the source electrode S1, and the drain electrode D1 of the thin film transistor ST1 can be arranged over the barrier film BR. The active layer ACT1 of the thin film transistor ST1 can include polycrystal silicon, single crystal silicon, low-temperature polycrystal silicon, amorphous silicon, or an oxide semiconductor. The active layer ACT1 which overlaps with the gate electrode G1 in a third direction (Z-axis direction) of a thickness direction of the substrate SUB1 can be defined as a channel region. The source electrode S1 and the drain electrode D1 can be regions which do not overlap with the gate electrode G1 in the third direction (Z-axis direction), and can have conductivity by doping a silicon semiconductor or an oxide semiconductor with ions or impurities.

[0124] The gate insulating film 130 can be arranged over the active layer ACT1, the source electrode S1, and the drain electrode D1 of each of the thin film transistors ST1. The gate insulating film 130 can be formed as an inorganic film including a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0125] The gate electrode G1 of the thin film transistor ST1 can be arranged over the gate insulating film 130. The gate electrode G1 can overlap with the active layer ACT1 in the third direction (Z-axis direction). The gate electrode G1 can be formed as a single layer or a plurality of layers made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0126] The interlayer insulating film 140 can include a first interlayer insulating film 141 and a second interlayer insulating film 142. The first interlayer insulating film 141 can be arranged over the gate electrode G1 of the thin film transistor ST1. The first interlayer insulating film 141 can be formed as an inorganic film including a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The first interlayer insulating film 141 can be formed as a plurality of inorganic films.

[0127] The capacitor electrode CAE can be arranged over the first interlayer insulating film 141. The capacitor electrode CAE can overlap with the gate electrode G1 of the thin film transistor ST1 in the third direction (Z-axis direction). A capacitor can be formed by the capacitor electrode CAE, the gate electrode G1, and the first interlayer insulating film 141 arranged between the capacitor electrode CAE and the gate electrode G1 due to the dielectric constant of the first interlayer insulating film 141. The capacitor electrode CAE can be formed as a single layer or a plurality of layers made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0128] The second interlayer insulating film 142 can be arranged over the capacitor electrode CAE. The second interlayer insulating film 142 can be formed as an inorganic film including a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The second interlayer insulating film 142 can be formed as a plurality of inorganic films.

[0129] A first anode connecting electrode ANDE1 can be disposed on the second interlayer insulating film 142. The first anode connecting electrode ANDE1 can be connected to the drain electrode D1 of the thin film transistor ST1 through a first connecting contact hole ANCT1 that passes through the gate insulating film 130, the first interlayer insulating film 141, and the second interlayer insulating film 142. The first anode connecting electrode ANDE1 can be formed as a single layer or a multilayer made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0130] A first planarization film 160 for planarizing a step due to the thin film transistor ST1 can be disposed on the first anode connecting electrode ANDE1. The first planarization film 160 can be formed as an organic film made of an acrylic resin, an epoxy resin, a phenol resin, a polyamide resin, a polyimide resin, or the like.

[0131] A second anode connecting electrode ANDE2 can be disposed on the first planarization film 160. The second anode connecting electrode ANDE2 can be connected to the first anode connecting electrode ANDE1 through a second connecting contact hole ANCT2 that passes through the first planarization film 160. The second anode connecting electrode ANDE2 can be formed as a single layer or a multilayer made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0132] A second planarization film 180 can be disposed on the second anode connecting electrode ANDE2. The second planarization film 180 can be formed as an organic film made of an acrylic resin, an epoxy resin, a phenol resin, a polyamide resin, a polyimide resin, or the like.

[0133] Light emitting elements LEL and banks 190 can be disposed on the second planarization film 180. Each of the light emitting elements LEL can include a pixel electrode 171, a light emitting layer 172, and a common electrode 173.

[0134] Figure 10 is Figure 9 an enlarged schematic cross-sectional view of the region B of

[0135] Referring to Figure 9 and Figure 10The pixel electrode 171 can be disposed on the second planarization film 180. The pixel electrode 171 can be connected to the second anode connection electrode ANDE2 through a third connection contact hole ANCT3 passing through the second planarization film 180.

[0136] In a top emission structure in which light is emitted from the light emitting layer 172 toward the common electrode 173, the pixel electrode 171 can be made of a metal having high reflectivity, such as a stacked structure of aluminum and titanium (Ti / Al / Ti), a stacked structure of aluminum and indium tin oxide (ITO) (ITO / Al / ITO), an APC alloy, and a stacked structure of an APC alloy and ITO (ITO / APC / ITO). The APC alloy can be an alloy of silver (Ag), palladium (Pd), and copper (Cu).

[0137] The bank 190 can be formed on the second planarization film 180 to separate the pixel electrode 171 so as to define the first light emitting part EA1, the second light emitting part EA2, the third light emitting part EA3, and the fourth light emitting part EA4 (see FIG. 1B). The bank 190 can cover edges of the pixel electrode 171. The bank 190 can be formed as an organic film made of an acrylic resin, an epoxy resin, a phenol resin, a polyamide resin, a polyimide resin, or the like. Figure 8 ) The bank 190 can cover edges of the pixel electrode 171. The bank 190 can be formed as an organic film made of an acrylic resin, an epoxy resin, a phenol resin, a polyamide resin, a polyimide resin, or the like.

[0138] Each of the first light emitting part EA1, the second light emitting part EA2, the third light emitting part EA3, and the fourth light emitting part EA4 can be a region in which the pixel electrode 171, the light emitting layer 172, and the common electrode 173 are sequentially stacked and holes from the pixel electrode 171 and electrons from the common electrode 173 recombine with each other in the light emitting layer 172 to emit light.

[0139] The light emitting layer 172 can be disposed on the pixel electrode 171 and the bank 190. The light emitting layer 172 can include an organic material to emit light of one color. For example, the light emitting layer 172 can include a hole transport layer, an organic material layer, and an electron transport layer.

[0140] The common electrode 173 can be disposed on the light emitting layer 172. The common electrode 173 can cover the light emitting layer 172. The common electrode 173 can be a common layer commonly formed in the first light emitting part EA1, the second light emitting part EA2, the third light emitting part EA3, and the fourth light emitting part EA4. A cap layer (not shown) can be formed on the common electrode 173.

[0141] In the top emission structure, the common electrode 173 can be made of a transparent conductive material (TCO) (such as ITO or indium zinc oxide (IZO)) or a semi-transmissive conductive material (such as magnesium (Mg), silver (Ag), or an alloy of magnesium (Mg) and silver (Ag)) capable of transmitting light through the common electrode 173. In the case where the common electrode 173 is made of the semi-transmissive conductive material, the emission efficiency can be increased by a microcavity.

[0142] The encapsulation layer TFEL can be disposed on the common electrode 173. The encapsulation layer TFEL can include at least one inorganic film to prevent oxygen or moisture from penetrating into the light emitting element layer EML. The encapsulation layer TFEL can include at least one organic film to protect the light emitting element layer EML from foreign substances such as dust. For example, the encapsulation layer TFEL can include a first encapsulation inorganic film TFE1, an encapsulation organic film TFE2, and a second encapsulation inorganic film TFE3.

[0143] The first encapsulation inorganic film TFE1 can be disposed on the common electrode 173, the encapsulation organic film TFE2 can be disposed on the first encapsulation inorganic film TFE1, and the second encapsulation inorganic film TFE3 can be disposed on the encapsulation organic film TFE2. Each of the first encapsulation inorganic film TFE1 and the second encapsulation inorganic film TFE3 can be formed as a plurality of films in which one or more inorganic films of a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, and an aluminum oxide layer are alternately stacked with each other. The encapsulation organic film TFE2 can be an organic film made of an acrylic resin, an epoxy resin, a phenol resin, a polyamide resin, a polyimide resin, or the like.

[0144] The touch sensor layer TSL can be disposed on the encapsulation layer TFEL. The touch sensor layer TSL can include a first touch insulating film TINS1, a first connection part BE1, a second touch insulating film TINS2, a driving electrode TE, and a sensing electrode RE.

[0145] The first touch insulating film TINS1 can be formed as an inorganic film including a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0146] The first connection part BE1 can be disposed on the first touch insulating film TINS1. The first connection part BE1 can be formed as a single layer or a plurality of layers made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0147] The second touch insulating film TINS2 can be disposed on the first connection part BE1. The second touch insulating film TINS2 can be formed as an inorganic film including a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. In another embodiment, the second touch insulating film TINS2 can be formed as an organic film made of an acrylic resin, an epoxy resin, a phenol resin, a polyamide resin, a polyimide resin, or the like.

[0148] The driving electrodes TE and the sensing electrodes RE can each be disposed on the second touch insulating film TINS2. The dummy pattern, the first touch driving lines, the second touch driving lines, and the touch sensing lines, and the driving electrodes TE and the sensing electrodes RE can be disposed on the second touch insulating film TINS2. Each of the driving electrodes TE and the sensing electrodes RE can be formed as a single layer or a multi-layer made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0149] The driving electrodes TE and the sensing electrodes RE can overlap the first connection portions BE1 in the third direction (Z-axis direction). The driving electrodes TE can be connected to the first connection portions BE1 through the touch contact holes TCNT1 passing through the second touch insulating film TINS2.

[0150] The total reflection layer TRL can be disposed on the touch sensor layer TSL. The total reflection layer TRL can be a layer that totally reflects light, among the light from the light emitting portions EA1, EA2, EA3, and EA4, propagating in a side direction rather than in an upward direction (Z-axis direction) so that the light propagating in the side direction propagates in the upward direction (Z-axis direction). The total reflection layer TRL can include a low-refraction pattern 401 and a high-refraction adhesive layer 402.

[0151] The low-refraction pattern 401 can be disposed on the second touch insulating film TINS2. The low-refraction pattern 401 can overlap the bank 190 in the third direction (Z-axis direction) and can not overlap the light emitting portions EA1, EA2, EA3, and EA4. The low-refraction pattern 401 can overlap the driving electrodes TE, the connection portions BE1 and BE2, and / or the sensing electrodes RE in the third direction (Z-axis direction).

[0152] The low-refraction pattern 401 can have a cross-section with a tapered shape or a trapezoidal shape. The low-refraction pattern 401 can include an inclined surface adjacent to each of the light emitting portions EA1, EA2, EA3, and EA4. A taper angle of the inclined surface of the low-refraction pattern 401 can be less than or equal to about 90°. The taper angle of the low-refraction pattern 401 can be an inclined angle of the inclined surface formed between the second touch insulating film TINS2 and the inclined surface of the low-refraction pattern 401.

[0153] Referring to Figure 9 and Figure 10 The low-refraction pattern 401 can include a plurality of openings OPE1, and each of the openings OPE1 can overlap one of the light emitting portions EA1, EA2, EA3, and EA4 in the third direction (Z-axis direction). Each of the openings OPE1 of the low-refraction pattern 401 can have an area greater than an area of each of the corresponding light emitting portions EA1, EA2, EA3, and EA4.

[0154] The low-refraction pattern 401 can be formed as an organic film or as an organic film including an inorganic filler. The organic film can be made of an acrylic resin, a methacrylic resin, a polyisoprene, a vinyl resin, an epoxy resin, a phenol resin, a urethane resin, a polyamide resin, or a polyimide resin, but is not limited thereto. The inorganic filler can be a metal particle, but is not limited thereto.

[0155] In an embodiment, the refractive index of the low-refraction pattern 401 can be in the range of about 1.40 to about 1.60. In an embodiment, the refractive index of the low-refraction pattern 401 can be in the range of about 1.45 to about 1.55. The refractive index described herein can be measured using an optical measuring instrument such as an ellipsometer or a spectroscopic reflectometer. The ellipsometer can measure the refractive index of the inorganic film by measuring the amount of polarization change of incident light and reflected light on the inorganic film and calculating the thickness and complex refractive index of the inorganic film. The spectroscopic reflectometer can measure the refractive index of the inorganic film by comparing the intensity of light obtained by changing the wavelength with each other. The refractive index can be a value measured at normal temperature and pressure.

[0156] The high-refraction adhesive layer 402 can be disposed on the low-refraction pattern 401 and the second touch insulating film TINS2. The high-refraction adhesive layer 402 can fill the openings OPE1 of the low-refraction pattern 401 and cover the low-refraction pattern 401. Accordingly, the high-refraction adhesive layer 402 can be used to planarize the steps formed by the driving electrodes TE, the sensing electrodes RE, and the first connection portions BE1. The high-refraction adhesive layer 402 can adhere or join the display panel 100 and the front stack structure 200 (see Figure 6 ) to each other. The high-refraction adhesive layer 402 can be in contact with the second touch insulating film TINS2 on the lower surface of the high-refraction adhesive layer 402 and with the polarizing film 210 on the upper surface of the high-refraction adhesive layer 402.

[0157] In an embodiment, the refractive index of the high-refraction adhesive layer 402 can be in the range of about 1.55 to about 1.65. In an embodiment, the refractive index of the high-refraction adhesive layer 402 can be in the range of about 1.58 to about 1.62. In an embodiment, the refractive index of the high-refraction adhesive layer 402 can be greater than the refractive index of the low-refraction pattern 401.

[0158] Referring to Figure 10 , light emitted from the light emitting element LEL can include front light L1 emitted in a front direction (Z-axis direction) and side light L2 emitted in a side direction other than the front direction. According to the difference in refractive index between the low-refraction pattern 401 and the high-refraction adhesive layer 402, the side light L2 can be refracted or totally reflected at the interface between the low-refraction pattern 401 and the high-refraction adhesive layer 402. In the case where the light path of the side light L2 is changed to the front direction (Z-axis direction), light efficiency can be increased.

[0159] The high-refractive adhesive layer 402 can include an aromatic monomer, an aliphatic monomer, a xylene resin, a plasticizer, and inorganic particles. The high-refractive adhesive layer 402 can be formed by curing a composition including two or more aromatic monomers, three or more aliphatic monomers, one or more xylene resins, one or more plasticizers, and inorganic particles.

[0160] The high-refractive adhesive layer 402 can include an aromatic monomer that can increase the refractive index. The aromatic monomer can be an aromatic (meth)acrylate. The aromatic (meth)acrylate can be a (meth)acrylate monomer including at least one aromatic substituent. The type of the aromatic (meth)acrylate is not particularly limited, but examples of the aromatic (meth)acrylate can include a (meth)acrylate including an aryl group, etc., in which the number of carbon atoms forming a ring is 6 to 30, 6 to 20, or 6 to 10.

[0161] As the aromatic (meth)acrylate, a monofunctional or a polyfunctional aromatic (meth)acrylate monomer can be used.

[0162] Examples of the monofunctional aromatic (meth)acrylate monomer can include a phenyl (meth)acrylate, a benzyl (meth)acrylate, a phenoxyethyl (meth)acrylate, a phenoxypropyl (meth)acrylate, a phenoxydiethyleneglycol (meth)acrylate, a phenoxyhydroxypropyl (meth)acrylate, a phenylthioethyl (meth)acrylate, a phenylbenzyl (meth)acrylate, etc., but are not limited thereto.

[0163] Examples of the multifunctional aromatic (meth)acrylate monomer can include difunctional aromatic (meth)acrylate monomers, etc. For example, examples of the multifunctional aromatic (meth)acrylate monomer can include bisphenol A (meth)acrylate, bisphenol A ethoxylate (meth)acrylate, 2,2-bis((meth)acryloyloxyphenyl)propane, 2,2-bis[4-(3-(meth)acryloyloxy)-2-hydroxypropoxyphenyl]propane, 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxidiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane, 2(4-(meth)acryloyloxydiethoxyphenyl)-2(4-(meth)acryloyloxydiethoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, 2-(4-propenoyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, etc., but are not limited thereto.

[0164] The high-refractive adhesive layer 402 can include a first aromatic monomer and a second aromatic monomer. The first aromatic monomer and the second aromatic monomer can be different from each other, and can each be a monofunctional aromatic (meth)acrylate. In an embodiment, the first aromatic monomer can be an aromatic (meth)acrylate including sulfur, and the second aromatic monomer can be an aromatic (meth)acrylate not including sulfur. In an embodiment, the molecular weight of the first aromatic monomer can be less than the molecular weight of the second aromatic monomer. In an embodiment, the molecular weight of the first aromatic monomer can be less than about 220 g / mol, and the molecular weight of the second aromatic monomer can be greater than or equal to about 220 g / mol. In an embodiment, the molecular weight of the first aromatic monomer can be in the range of about 100 g / mol to about 210 g / mol, and the molecular weight of the second aromatic monomer can be in the range of about 220 g / mol to about 400 g / mol. In an embodiment, the first aromatic monomer can be 2-(phenyl)thioethyl acrylate, and the second aromatic monomer can be o-phenylbenzyl acrylate.

[0165] The high-refractive adhesive layer 402 can include an aliphatic monomer that can increase flexibility and reduce rigidity. The aliphatic monomer can be an aliphatic (meth)acrylate, which can be a monofunctional or multifunctional aliphatic (meth)acrylate.

[0166] Examples of monofunctional aliphatic (meth)acrylates may include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, isopentyl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, lauryl (meth)acrylate, hydroxybutyl (meth)acrylate, 2-{2-[(2-ethylhexyl)oxy]ethoxy}ethyl acrylate (DEHEA), and the like, but are not limited thereto.

[0167] Examples of the multifunctional aliphatic (meth)acrylate may include: difunctional aliphatic (meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and 1,6-hexanediol di(meth)acrylate; trifunctional aliphatic (meth)acrylates such as trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolethanol tri(meth)acrylate, and trimethylolmethane tri(meth)acrylate; and tetrafunctional aliphatic (meth)acrylates such as pentaerythritol tetra(meth)acrylate, but are not limited thereto.

[0168] The high-refractive adhesive layer 402 can include a first aliphatic monomer, a second aliphatic monomer, and a third aliphatic monomer. The first aliphatic monomer to the third aliphatic monomer can be different from each other, and can each be a monofunctional aliphatic (meth)acrylate. The first aliphatic monomer and the second aliphatic monomer can be aliphatic (meth)acrylates including branched alkyl groups, and the third aliphatic monomer can be an aliphatic (meth)acrylate including a linear alkyl group and a hydroxyl group. In an embodiment, the molecular weight of the first aliphatic monomer can be greater than the molecular weight of the second aliphatic monomer and the molecular weight of the third aliphatic monomer, and the molecular weight of the second aliphatic monomer can be greater than the molecular weight of the third aliphatic monomer. In an embodiment, the molecular weight of the first aliphatic monomer can be greater than or equal to about 250 g / mol, the molecular weight of the second aliphatic monomer can be in a range of about 150 g / mol to about 200 g / mol, and the molecular weight of the third aliphatic monomer can be less than about 150 g / mol. In an embodiment, the first aliphatic monomer can be 2-{2-[(2-ethylhexyl)oxy]ethoxy}ethyl acrylate (DEHEA), the second aliphatic monomer can be 2-ethylhexyl acrylate, and the third aliphatic monomer can be 4-hydroxybutyl acrylate.

[0169] The high-refractive adhesive layer 402 can include a xylene resin that can increase the refractive index of the high-refractive adhesive layer 402 and increase the flexibility of the high-refractive adhesive layer 402. Examples of the xylene resin can include a linear xylene resin, an alkyl phenol-modified xylene resin, a phenol-modified novolak-type xylene resin, a phenol-modified melein-type xylene resin, a polyol-modified xylene resin, a hydrogenated rosin ester, etc., but are not limited thereto. Other types of xylene resins can be used as the xylene resin. In an embodiment, the xylene resin can be represented by the following Formula 1:

[0170] [Formula 1]

[0171]

[0172] In Formula 1, Me can be a methyl group, R1 to R4 can each independently be hydrogen, deuterium, a halogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, n1 to n4 can each independently be an integer of 0 to 4 and at least one of n1 to n4 can be 2 or more, r1 to r4 can each independently be an integer of 0 to 4, and m can be an integer of 0 to 20.

[0173] In an embodiment, n1 + r1 can be 4, n2 + r2 can be 4, n3 + r3 can be 4, and n4 + r4 can be 4.

[0174] In an embodiment, n1 to n4 can all be 2.

[0175] In an embodiment, Formula 1 can be the following Formula 1-1, and m can be an integer of 0 to 100.

[0176] [Formula 1-1]

[0177]

[0178] The high-refractive adhesive layer 402 can include a plasticizer that can reduce rigidity of the high-refractive adhesive layer 402 and increase flexibility of the high-refractive adhesive layer 402. A sulfurized aromatic compound can be used as the plasticizer. The sulfurized aromatic compound can be diphenyl sulfide, methyl phenyl sulfide, 4-methoxy thioanisole, 2-(phenylthio)ethanol, methoxy methyl phenyl sulfide, bis(4-hydroxyphenyl) sulfide, bis(4-aminophenyl) sulfide, bis(2-aminophenyl) sulfide, bis(phenylthio)methane, thioxanthen-9-one, 2-chlorothioxanthenone, thianthrene, 2-aminophenyl phenyl sulfide, 4,4'-dipyridyl sulfide, 1,2-bis(phenylthio)ethane, phenyl trifluoromethyl sulfide, styryl sulfide, allyl phenyl sulfide, 2-(methylthio)aniline, 2-(methylthio)pyridine, 2-fluorothioanisole, 2-chlorothioanisole, 2-bromothioanisole, 4-bromothioanisole, 4-(methylthio)benzaldehyde, (phenylthio)acetonitrile, 2-methoxythioanisole, 2-methyl-3-(methylthio)furan, S-phenyl thioacetate, or (oxybis(ethane-2,1-diyl))bis(phenyl sulfide).

[0179] In an embodiment, the sulfurized aromatic compound can be represented by the following Formula 2:

[0180] [Formula 2]

[0181]

[0182] In Formula 2, R5and R6may each independently be hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group, r5and r6may each independently be an integer of 0 to 5, and k can be an integer of 0 to 3.

[0183] In an embodiment, Formula 2 can be represented by one of the following compounds.

[0184]

[0185] The high-refractive adhesive layer 402 can include inorganic particles that can adjust a refractive index of the high-refractive adhesive layer 402. The inorganic particles can include at least one of zirconium oxide (ZrO2), titanium oxide (TiO2), aluminum oxide (Al2O3), and silicon oxide (SiO2). In an embodiment, the inorganic particles can include zirconium oxide (ZrO2). The inorganic particles can be dispersed in the high-refractive adhesive layer 402 and widely spread throughout the high-refractive adhesive layer 402.

[0186] The inorganic particles can be implemented in various shapes. For example, the shape of the inorganic particles can be spherical, plate-like, cubic, or amorphous, but is not limited thereto. The average particle diameter of the inorganic particles can be less than or equal to about 25 nm. For example, the average particle diameter of the inorganic particles can be in the range of about 1 nm to about 25 nm. The average particle diameter of the inorganic particles can be the particle size (D 50 ) at 50 vol% on a cumulative size-distribution curve.

[0187] In an embodiment, the high-refractive adhesive layer 402 can include 40 wt% to 80 wt% of an aromatic monomer based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 10 wt% to 30 wt% of an aliphatic monomer based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 10 wt% to 25 wt% of a xylene resin based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 10 wt% to 20 wt% of a sulfurized aromatic compound based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 1 wt% to 3 wt% of inorganic particles based on the total weight of the high-refractive adhesive layer 402.

[0188] In an embodiment, the high-refractive adhesive layer 402 can include 40 wt% to 60 wt% of an aromatic monomer based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 15 wt% to 25 wt% of an aliphatic monomer based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 15 wt% to 20 wt% of a xylene resin based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 10 wt% to 15 wt% of a sulfurized aromatic compound based on the total weight of the high-refractive adhesive layer 402. The high-refractive adhesive layer 402 can include 1 wt% to 2 wt% of inorganic particles based on the total weight of the high-refractive adhesive layer 402.

[0189] The high-refractive adhesive layer 402 can have a high-refractive property by including an aromatic monomer, and can increase the flexibility of the high-refractive adhesive layer 402 by introducing an aliphatic monomer into the high-refractive adhesive layer 402. In a case where the content of inorganic particles exceeds 3 wt%, the high-refractive adhesive layer 402 can have high strength, but can be easily damaged. By setting the content of inorganic particles within 3 wt%, it is possible to increase the emission efficiency while preventing the high-refractive adhesive layer 402 from being damaged. Accordingly, the high-refractive adhesive layer 402 can be applied as an adhesive layer of a foldable display device 10 (see FIG. 1). Figure 1 ) of the present disclosure. The content of inorganic particles can be based on the total weight of the high-refractive adhesive layer 402.

[0190] In embodiments, the first aromatic monomer can be present in an amount higher than the second aromatic monomer. The mass ratio between the first aromatic monomer and the second aromatic monomer can be in the range of about 1.5:1 to about 3:1.

[0191] In embodiments, the first aliphatic monomer can be present in an amount significantly higher than the second aliphatic monomer and the third aliphatic monomer, and the second aliphatic monomer can be present in an amount higher than the third aliphatic monomer. The mass ratio between the first aromatic monomer and the third aromatic monomer can be in the range of about 7:1 to about 10:1. The mass ratio between the second aromatic monomer and the third aromatic monomer can be in the range of about 1.5:2 to about 3:1.

[0192] In embodiments, the high-refractive adhesive layer 402 can further include an additive. To adjust the physical properties required for the resin composition, a conventional additive can be appropriately used as the additive. Examples of the additive can include a light stabilizer, a crosslinking agent, an antioxidant, a chain transfer agent, a photosensitizer, a polymerization inhibitor, a leveling agent, a surfactant, a UV absorber, a storage stabilizer, an antistatic agent, an inorganic filler, a pigment, and a dye, but are not limited thereto. The additive can be used alone or in combination of two or more additives.

[0193] The high-refractive adhesive layer 402 can have a storage modulus (G') in the range of about 1.0 MPa to about 10 MPa at -20°C. The high-refractive adhesive layer 402 can have a storage modulus in the range of about 0.01 MPa to about 0.1 MPa at room temperature (25°C). The high-refractive adhesive layer 402 can have a storage modulus in the range of about 0.01 MPa to about 0.05 MPa at 60°C. For example, the storage modulus of the high-refractive adhesive layer 402 at -20°C can be in the range of about 1.5 MPa to about 3.0 MPa, the storage modulus of the high-refractive adhesive layer 402 at room temperature (25°C) can be in the range of about 0.015 MPa to about 0.05 MPa, and the storage modulus of the high-refractive adhesive layer 402 at 60°C can be in the range of about 0.01 MPa to about 0.03 MPa.

[0194] The high-refractive adhesive layer 402 can have a loss modulus (G") in the range of about 3.5 MPa to about 10 MPa at -20°C. The high-refractive adhesive layer 402 can have a loss modulus in the range of about 0.001 MPa to about 0.1 Mpa at room temperature (25°C). The high-refractive adhesive layer 402 can have a loss modulus in the range of about 0.001 MPa to about 0.01 MPa at 60°C. For example, the high-refractive adhesive layer 402 can have a loss modulus in the range of about 4.5 MPa to about 7.0 MPa at -20°C, the high-refractive adhesive layer 402 can have a loss modulus in the range of about 0.005 MPa to about 0.01 MPa at room temperature (25°C), and the high-refractive adhesive layer 402 can have a loss modulus in the range of about 0.001 MPa to about 0.005 MPa at 60°C.

[0195] The storage modulus (G') can be the energy stored by elastic deformation without loss, and the loss modulus (G") can be the energy lost due to viscosity. The viscoelastic ratio (Tan delta) can be the ratio of the loss modulus (G") to the storage modulus (G') (G" / G'), and when the viscoelastic ratio is greater than 1, it means that the viscosity can be greater than the elasticity. The storage modulus and the loss modulus can be measured by methods well known to one of ordinary skill in the art. In embodiments, the storage modulus and the loss modulus can be measured by dynamic mechanical analysis (DMA), and the viscoelastic ratio can also be calculated. The storage modulus, the loss modulus, and the viscoelastic ratio can be measured or calculated by ASTM D4065, D4440, and D5279, respectively.

[0196] The high-refractive adhesive layer 402 can have a viscoelastic ratio in the range of about 2.9 to about 6 at -20°C. The high-refractive adhesive layer 402 can have a viscoelastic ratio in the range of about 0.1 to about 1 at room temperature (25°C). The high-refractive adhesive layer 402 can have a viscoelastic ratio in the range of about 0.01 to about 0.5 at 60°C. For example, the high-refractive adhesive layer 402 can have a viscoelastic ratio in the range of about 3.0 to about 4.0 at -20°C, the high-refractive adhesive layer 402 can have a viscoelastic ratio in the range of about 0.3 to about 0.6 at room temperature (25°C), and the high-refractive adhesive layer 402 can have a viscoelastic ratio in the range of about 0.05 to about 0.2 at 60°C.

[0197] In the case where the storage modulus, the loss modulus, and the viscoelastic ratio of the high-refractive adhesive layer 402 satisfy the above ranges at each temperature, the flexibility of the high-refractive adhesive layer 402 can be increased, and even in the case where the display device 10 (see FIG. 1) is bent, the display device 10 can be prevented from being damaged. Figure 1) be maintained. The viscoelasticity ratio of the high-refractive adhesive layer 402 at low temperatures can be high, so that the adhesive strength can be excellent, and the storage modulus of the high-refractive adhesive layer 402 at low temperatures can be high, so that cracks can be prevented. In the case where the storage modulus, the loss modulus, and the viscoelasticity ratio of the high-refractive adhesive layer 402 are outside the above ranges at each temperature, the deformation of the high-refractive adhesive layer 402 according to temperature can increase, so that the durability and the reliability of the display device 10 (see Figure 1 ) can decrease.

[0198] The glass transition temperature (Tg) of the high-refractive adhesive layer 402 can be in the range of about -30°C to about -10°C. For example, the glass transition temperature (Tg) of the high-refractive adhesive layer 402 can be in the range of about -25°C to about -15°C. In the case where the high-refractive adhesive layer 402 has a glass transition temperature in the above range, the durability of the high-refractive adhesive layer 402 can be excellent.

[0199] The high-refractive adhesive layer 402 can have a creep value in the range of about 10% to about 40% at 60°C. In the case where the creep value is in the above range, the high-refractive adhesive layer 402 can resist external force and can not be deformed. In the case where the creep value is less than 10%, the flexibility of the high-refractive adhesive layer 402 can decrease during a folding operation, and in the case where the creep value exceeds 40%, the restoring force of the high-refractive adhesive layer 402 can decrease.

[0200] The high-refractive adhesive layer 402 can have a recovery value in the range of about 70% to about 80% at -20°C. In the case where the recovery value is in the above range, the high-refractive adhesive layer 402 can have excellent restoring force even in a low-temperature environment.

[0201] The creep value as used herein can be a strain of the target sample in a case where a shear stress of 2000 Pa is applied to the target sample for 10 minutes at a corresponding temperature. In the creep experiment, a phenomenon in which the deformed target sample recovers in a case where a shear stress is applied to the target sample for a certain time and the shear stress is removed can be referred to as recovery, and the recovery can be a strain value of the target sample that recovers within 10 minutes after a shear stress of 2000 Pa is applied to the target sample for 10 minutes and the shear stress is removed. The creep value and the recovery value of the adhesive layer sample can be obtained by an evaluation using a DHR device available from TA Instruments, which has a loading force of 1 N and an axial force of 1.0 N, after the adhesive layer sample having a diameter of 8 mm and a thickness of 800 µm is attached to parallel plates made of stainless steel. The creep of the adhesive layer sample is measured by applying a shear stress of 2000 Pa to the adhesive layer sample for 10 minutes after the adhesive layer sample is stabilized at a temperature of 60°C for 60 seconds, and the recovery of the adhesive layer sample is measured within 10 minutes after the shear stress is removed.

[0202] The high-refractive adhesive layer 402 can include an ultraviolet absorber. The ultraviolet absorber can absorb ultraviolet rays (UV) having a wavelength in a range of about 300 nm to about 380 nm.

[0203] The ultraviolet absorber can include a light-absorbing dye that absorbs light. For example, the ultraviolet absorber can include a benzotriazole-based light-absorbing dye, a benzophenone-based light-absorbing dye, a salicylic acid-based light-absorbing dye, a salicylate-based light-absorbing dye, a cyanoacrylate-based light-absorbing dye, a cinnamate-based light-absorbing dye, an oxanilide-based light-absorbing dye, a polystyrene-based light-absorbing dye, a polyferrocenylsilane-based light-absorbing dye, a methine-based light-absorbing dye, an azomethine-based light-absorbing dye, a triazine-based light-absorbing dye, a p-aminobenzoic acid-based light-absorbing dye, a cinnamic acid-based light-absorbing dye, a urocanic acid-based light-absorbing dye, or a combination thereof, but is not limited thereto.

[0204] The polarizing film 210 can be disposed on the high-refractive adhesive layer 402. Since the high-refractive adhesive layer 402 has both a planarization function and an adhesive function, the polarizing film 210 can be directly disposed on the high-refractive adhesive layer 402.

[0205] The specification can provide a composition for an adhesive layer including the above-described aromatic monomer, aliphatic monomer, xylene resin, sulfurized aromatic compound, and inorganic particles.

[0206] In a case where the composition for the adhesive layer is photocured or thermally cured, an organic material layer having the above-described physical properties can be obtained.

[0207] Among the above-mentioned functional groups, "substituted or unsubstituted" can mean substituted with one or more substituent selected from the group consisting of a deuterium atom, a halogen atom, a cyano group, a nitro group, an amino group, a silicon group, an oxygen group, a sulfur group, a sulfinyl group, a sulfonyl group, a carbonyl group, a boron group, a phosphine oxide group, a phosphine sulfide group, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a hydrocarbon ring group, an aryl group, and a heterocyclic group, or unsubstituted. Each of the above-mentioned substituents can be substituted or unsubstituted. For example, a biphenyl group can be an aryl group or a phenyl group.

[0208] Examples of a halogen atom as used herein can include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0209] An alkyl group as used herein can be a linear alkyl group, a branched alkyl group, or a cyclic alkyl group. The number of carbon atoms of the alkyl group is 1 or more and 50 or less, 1 or more and 30 or less, 1 or more and 20 or less, 1 or more and 10 or less, or 1 or more and 6 or less. Examples of the alkyl group can include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an iso-butyl group, a 2-ethylbutyl group, a 3,3-dimethylbutyl group, an n-pentyl group, an iso-pentyl group, a neopentyl group, a t-pentyl group, a cyclopentyl group, a 1-methylpentyl group, a 3-methylpentyl group, a 2-ethylpentyl group, a 4-methyl-2-pentyl group, an n-hexyl group, a 1-methylhexyl group, a 2-ethylhexyl group, a 2-butylhexyl group, a cyclohexyl group, a 4-methylcyclohexyl group, a 4-t-butylcyclohexyl group, an n-heptyl group, a 1-methylheptyl group, a 2,2-dimethylheptyl group, a 2-ethylheptyl group, a 2-butylheptyl group, an n-octyl group, a t-octyl group, a 2-ethyloctyl group, a 2-butyloctyl group, a 2-hexyloctyl group, a 3,7-dimethyloctyl group, a cyclooctyl group, an n-nonyl group, an n-decyl group, an adamantyl group, a 2-ethyldodecyl group, a 2-butyldodecyl group, a 2-hexyldodecyl group, a 2-octyldodecyl group, an n-undecyl group, an n-dodecyl group, a 2-ethyldodecyl group, a 2-butyldodecyl group, a 2-hexyldodecyl group, a 2-octyldodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, a 2-ethyihexadecyl group, a 2-butyihexadecyl group, a 2-hexyihexadecyl group, a 2-octyihexadecyl group, an n-heptadecyl group, an n-octadecyl group, an n-nonadecyl group, an n-eicosyl group, a 2-ethyleicosyl group, a 2-butyileicosyl group, a 2-hexyleicosyl group, a 2-octyleicosyl group, an n-uncosyl group, an n-docosyl group, an n-tricosyl group, an n-tetracosyl group, an n-pentacosyl group, an n-hexacosyl group, an n-heptacosyl group, an n-octacosyl group, an n-nonacosyl group, an n-triacontyl group, and the like, but are not limited thereto.

[0210] As used herein, an aryl group can be any functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group can be a monocyclic aryl group or a polycyclic aryl group. The number of carbon atoms forming a ring in the aryl group can be 6 or more and 30 or less, 6 or more and 20 or less, or 6 or more and 15 or less. Examples of the aryl group can include a phenyl group, a naphthyl group, a fluorenyl group, an anthryl group, a phenanthryl group, a biphenyl group, a terphenyl group, a quaterphenyl group, a quinquephenyl group, a sexiphenyl group, a triphenylenyl group, a pyrenyl group, a benzofluoranthene group, a chrysenyl group, and the like, but are not limited thereto.

[0211] As used herein, a heteroaryl group can include one or more of B, O, N, P, Si, and S as a heteroatom. In the case where the heteroaryl group includes two or more heteroatoms, the two or more heteroatoms can be the same as or different from each other. The heteroaryl group can be a monocyclic heterocyclic group or a polycyclic heterocyclic group. The number of carbon atoms forming a ring in the heteroaryl group can be 2 or more and 30 or less, 2 or more and 20 or less, or 2 or more and 10 or less. Examples of the heteroaryl group can include a thiophenyl group, a furanyl group, a pyrrolyl group, an imidazolyl group, a triazolyl group, a pyridyl group, a bipyridyl group, a pyrimidinyl group, a triazinyl group, a triazolyl group, an acridinyl group, a pyridazinyl group, a pyrazinyl group, a quinolinyl group, a quinazolinyl group, a quinoxalinyl group, a phenoxazinyl group, a phthalazinyl group, a pyridopyrimidinyl group, a pyridopyrazinyl group, a pyrazinopyrazinyl group, an isoquinolinyl group, an indolyl group, a carbazolyl group, an N-arylcarbazolyl group, an N-heteroarylcarbazolyl group, an N-alkylcarbazolyl group, a benzoxazolyl group, a benzimidazolyl group, a benzothiazolyl group, a benzocarbazolyl group, a benzothiophenyl group, a dibenzothiophenyl group, a thienothiophenyl group, a benzofuranyl group, a phenanthrolinyl group, a thiazolyl group, an isoxazolyl group, an oxazolyl group, an oxadiazolyl group, a thiadiazolyl group, a phenothiazinyl group, a dibenzosilacyclopentadienyl group, a dibenzofuranyl group, and the like, but are not limited thereto.

[0212] As used herein, a (meth)acrylate can be an acrylate or a methacrylate.

[0213] Hereinafter, examples will be described in more detail through several experimental examples.

[0214] <Preparation of a composition for a high-refractive adhesive layer>

[0215] The composition of Example 1 was prepared by mixing an aromatic monomer (50 wt%), an aliphatic monomer (20 wt%), a xylene resin (15 wt%), a vulcanized aromatic compound (13 wt%), and inorganic particles (2 wt%) with each other.

[0216] Two aromatic monomers were used: 2-(phenyl)thioethyl acrylate was used as the first aromatic monomer, and o-phenylbenzyl acrylate was used as the second aromatic monomer, and the weight ratio between the first aromatic monomer and the second aromatic monomer was 2:1.

[0217] Three kinds of aliphatic monomers were used: the first aliphatic monomer was 2-{2-[(2- ethylhexyl)oxy]ethoxy}ethyl acrylate (DEHEA), the second aliphatic monomer was 2- ethylhexyl acrylate, and the third aliphatic monomer was 4-hydroxybutyl acrylate. The weight ratio between the first aliphatic monomer, the second aliphatic monomer, and the third aliphatic monomer was 9:2:1.

[0218] The following Formula 1-1 was used as the xylene resin:

[0219] [Formula 1-1]

[0220]

[0221] In Formula 1-1, m can be an integer of 1 to 100.

[0222] 1,2-bis(phenylthio)ethane was used as the sulfurized aromatic compound, and zirconium oxide was used as the inorganic particle.

[0223] The composition of Comparative Example 1 was prepared by excluding the three kinds of aliphatic monomers from the composition of Example 1 and changing the content of the aromatic monomer to 70 wt%. The weight ratio between the two kinds of aromatic monomers was the same as in Example 1.

[0224] <Formation and evaluation of high-refractive adhesive layer>

[0225] The compositions of Example 1 and Comparative Example 1 were applied to the adherend by using inkjet printing or Y-map coating and the composition was UV-cured to form a high-refractive adhesive layer.

[0226] The formed high-refractive adhesive layer was evaluated, and is shown in Table 1.

[0227] [Table 1]

[0228]

[0229] Referring to Table 1, it can be seen that the storage modulus, loss modulus, and viscoelastic ratio at -20℃ are higher in Example 1 than in Comparative Example 1. The viscoelastic ratio of the high-refractive adhesive layer of Example 1 is high even at low temperatures, such that the adhesive strength of the high-refractive adhesive layer is excellent, and the storage modulus and loss modulus of the high-refractive adhesive layer of Example 1 are high, such that cracks can be prevented even during folding. The creep value of the high-refractive adhesive layer of Example 1 at 60℃ is 10% or more, such that the high-refractive adhesive layer can be sufficiently flexible even during folding operations, and the recovery of the high-refractive adhesive layer of Example 1 at -20℃ is 80% or more, such that the permanent set of the high-refractive adhesive layer after folding can be small. The high-refractive adhesive layer of Example 1 obtained a G (good) rating in the reliability evaluation.

[0230] On the other hand, the high-refractive adhesive layer of Comparative Example 1 exhibited low storage modulus and loss modulus at low temperatures, such that peeling defects occurred. The creep value of the high-refractive adhesive layer of Comparative Example 1 at 60℃ was less than 10%, such that the high-refractive adhesive layer can not have been sufficiently deformed during folding operations, and the recovery of the high-refractive adhesive layer of Comparative Example 1 at -20℃ was less than 70%. The high-refractive adhesive layer of Comparative Example 1 obtained an NG (not good) rating in the reliability evaluation.

[0231] The above description is an example of technical features of the present disclosure, and those skilled in the art to which the present disclosure pertains will be able to make various modifications and changes. Therefore, the embodiments of the present disclosure described above can be implemented alone or in combination with each other.

[0232] Therefore, the embodiments disclosed in the present disclosure are not intended to limit the technical spirit of the present disclosure, but to describe the technical spirit of the present disclosure, and the scope of the technical spirit of the present disclosure is not limited by these embodiments. The scope of protection of the present disclosure should be interpreted by the appended claims, and all technical spirits within the equivalent scope should be interpreted to be included in the scope of the present disclosure.

Claims

1. A display device comprising: a display unit including a light emitting element; a low-refractive pattern disposed on the display unit and including an opening overlapping the light emitting element in a thickness direction of the display unit; and a high-refractive adhesive layer disposed on the low-refractive pattern and the display unit and including inorganic particles, wherein the high-refractive adhesive layer includes 1 to 3 wt% of the inorganic particles based on a total weight of the high-refractive adhesive layer. 2.The display device of claim 1, further comprising: a polarizing film disposed on the high-refractive adhesive layer. The high-refractive adhesive layer is in contact with the polarizing film.

3. The display device according to claim 2, wherein 4.The display device of claim 1, wherein the low-refractive pattern has a refractive index in a range of 1.45 to 1.55, and the high-refractive adhesive layer has a refractive index in a range of 1.55 to 1.

65. The inorganic particles are at least one of zirconium oxide, titanium oxide, aluminum oxide, and silicon oxide.

5. The display device according to claim 1, wherein The inorganic particles are dispersed in the high-refractive adhesive layer.

6. The display device of claim 5, wherein, The high-refractive adhesive layer further includes an aromatic monomer and an aliphatic monomer.

7. The display device according to claim 1, wherein The aromatic monomer includes a first aromatic monomer and a second aromatic monomer different from each other.

8. The display device of claim 7, wherein, The aliphatic monomer includes a first aliphatic monomer, a second aliphatic monomer, and a third aliphatic monomer different from each other.

9. The display device according to claim 7, wherein The high-refractive adhesive layer further includes a xylene resin and a vulcanized aromatic compound.

10. The display device of claim 7, wherein, The high-refractive adhesive layer includes 40 to 80 wt% of the aromatic monomer, 10 to 30 wt% of the aliphatic monomer, 10 to 25 wt% of the xylene resin, 10 to 20 wt% of the vulcanized aromatic compound, and 1 to 3 wt% of the inorganic particles based on the total weight of the high-refractive adhesive layer.

11. The display device of claim 10, wherein, 12.The display device of claim 1, wherein the high-refractive adhesive layer has a storage modulus in a range of 1.0 to 10 MPa at -20℃, the high-refractive adhesive layer has a loss modulus in a range of 3.5 to 10 MPa at -20℃, and the high-refractive adhesive layer has a ratio of viscoelasticity in a range of 2.9 to 6 at -20℃. The high-refractive adhesive layer has a glass transition temperature in a range of -30℃ to -10℃.

13. The display device of claim 1, wherein, The high-refractive adhesive layer has a creep value in a range of 10 to 40% at 60℃.

14. The display device of claim 1, wherein, The high-refractive adhesive layer has a recovery value greater than or equal to 70% at -20℃.

15. The display device of claim 1, wherein, 16.The display device of claim 2, further comprising: a touch sensor layer disposed between the display unit and the low-refractive pattern, wherein the high-refractive adhesive layer is in contact with the touch sensor layer and the polarizing film. The low-refractive pattern has a tapered shape in a cross-sectional view.

17. The display device of claim 1, wherein, 18.A composition for an adhesive layer, comprising: a first aromatic monomer and a second aromatic monomer different from each other; ​ a first aliphatic monomer, a second aliphatic monomer, and a third aliphatic monomer, the first aliphatic monomer, the second aliphatic monomer, and the third aliphatic monomer being different from each other; and inorganic particles including at least one of zirconium oxide, titanium oxide, aluminum oxide, and silicon oxide, wherein the inorganic particles are included in an amount of 1 wt% to 3 wt% based on a total weight of the composition for the adhesive layer.

19. The composition for an adhesive layer according to claim 18, wherein, a molecular weight of the first aromatic monomer is less than a molecular weight of the second aromatic monomer, a content of the first aromatic monomer is higher than a content of the second aromatic monomer, a molecular weight of the first aliphatic monomer is greater than a molecular weight of the second aliphatic monomer and a molecular weight of the third aliphatic monomer, the molecular weight of the second aliphatic monomer is greater than the molecular weight of the third aliphatic monomer, a content of the first aliphatic monomer is higher than a content of the second aliphatic monomer and a content of the third aliphatic monomer, and the content of the second aliphatic monomer is higher than the content of the third aliphatic monomer.

20. The composition for an adhesive layer according to claim 18, further comprising: a xylene resin and a vulcanized aromatic compound.

21. An electronic device including a display device, the display device including: a display unit including a light emitting element; a low-refraction pattern arranged on the display unit and including an opening overlapping the light emitting element in a thickness direction of the display unit; and a high-refraction adhesive layer arranged on the low-refraction pattern and the display unit and including inorganic particles, wherein the high-refraction adhesive layer includes the inorganic particles in an amount of 1 wt% to 3 wt% based on a total weight of the high-refraction adhesive layer. ​

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