Display device and method for manufacturing display device

Abstract

The invention relates to a display device and a method for manufacturing the same. The display device includes: a display panel including a display area and a non-display area; and a coating layer directly disposed on a lower surface of the display panel and being a single layer. The coating layer includes a base layer and a plurality of fillers dispersed in the base layer, the base layer includes a resin material, and a surface of the coating layer has an irregular corrugated structure including curved valleys recessed toward the display panel and curved ridges protruding in a direction away from the display panel.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority and all benefits derived therefrom to Korean Patent Application No. 10 - 2023 - 0169621, filed on November 29, 2023, the content of which is incorporated herein by reference in its entirety. Technical field

[0003] The present disclosure relates to a display device and a method for manufacturing a display device, and more particularly, to a display device including a coating and a method for manufacturing a display device. Background art

[0004] Various display devices for multimedia devices (such as televisions, mobile phones, tablet computers, and game consoles) are being developed. The display device may include various functional layers to provide a color image with excellent quality to a user.

[0005] Recently, research has been conducted on thin - type display devices to implement various types of display devices (such as a display device including a curved surface, a rollable display device, or a foldable display device). By reducing the number of functional layers and by including functional layers having various functions, a thin - type display device can be realized. Summary of the invention

[0006] To implement a thin - type display device, it may be desirable to ensure the impact resistance of the display device. Therefore, research is being conducted on the structure of a display device having high impact resistance and a small thickness.

[0007] The present disclosure provides a display device and a method for manufacturing a display device, the display device having improved reliability and impact resistance by providing a single coating including a surface having a corrugated structure below a display panel.

[0008] Embodiments of the present invention provide a display device including: a display panel including a display area and a non - display area; and a coating that is directly disposed on a lower surface of the display panel and is a single layer, wherein the coating includes a base layer and a plurality of fillers dispersed in the base layer, the base layer includes a resin material, and a surface of the coating has an irregular corrugated structure including curved valleys that are recessed toward the display panel and curved ridges that protrude in a direction away from the display panel.

[0009] In an embodiment, a first portion of the coating adjacent to the surface may have a first curing rate, and a second portion of the coating farther from the surface than the first portion may have a second curing rate greater than the first curing rate.

[0010] In an embodiment, the coating may have an absorbance of about 3.0 or greater.

[0011] In an embodiment, the coating may have a storage modulus in the range of from about 0.01 megapascal (Mpa) to about 1 Mpa.

[0012] In an embodiment, the coating may have a thickness in the range of from about 50 micrometers (μm) to about 200 μm.

[0013] In an embodiment, the coating may have a thermal conductivity of about 100 watts per meter kelvin (W / m·K) or greater.

[0014] In an embodiment, the base layer may include a photocurable resin material.

[0015] In an embodiment, the plurality of fillers may include: a first filler including a light-blocking material; and a second filler including a material having a thermal conductivity of about 100 W / m·K or greater.

[0016] In an embodiment, the display device may further include a functional layer directly disposed on the surface of the coating, having a flat surface and including a light-transmissive material.

[0017] In an embodiment, the display device may further include a heat dissipation layer disposed on the surface of the coating and including a heat dissipation material.

[0018] In an embodiment, the display device may further include an electronic module disposed under the coating, wherein the display panel may include a signal transmission region and a non-transmission region adjacent to the signal transmission region, the electronic module may overlap with the signal transmission region, and the coating may overlap with the non-transmission region.

[0019] In an embodiment, the display device may further include a window disposed on the display panel and covering the display panel; and a light-blocking pattern disposed on the window and overlapping with the non-display region.

[0020] In an embodiment of the present invention, a method for manufacturing a display device includes: providing a display panel including a display region and a non-display region; providing a preliminary coating material on the lower surface of the display panel; and curing the preliminary coating material to form a coating directly disposed on the lower surface of the display panel and having an irregular corrugated structure on the surface of the coating, the corrugated structure including a curved valley recessed toward the display panel and a curved ridge protruding in a direction away from the display panel, wherein when curing the preliminary coating material to form the coating, the surface of the preliminary coating material is exposed to oxygen.

[0021] In an embodiment, the preliminary coating material includes: a base resin including a photocurable resin material; and a plurality of fillers dispersed in the base resin.

[0022] In an embodiment, when curing the preliminary coating material to form a coating, the concentration of oxygen exposed on the surface of the preliminary coating material may be about 50 parts per million (50 ppm) or greater.

[0023] In an embodiment, curing the preliminary coating material to form a coating may include: performing primary curing on the preliminary coating material to form a first preliminary coating having a first curing rate and a second preliminary coating adjacent to the first preliminary coating and having a second curing rate greater than the first curing rate; and performing secondary curing on the first preliminary coating and the second preliminary coating to form a coating having an irregular corrugated structure on its surface.

[0024] In an embodiment, the plurality of fillers may include: a first filler including a light-blocking material; and a second filler including a material having a thermal conductivity of about 100 W / m·K or greater.

[0025] In an embodiment, the preliminary coating material disposed on the lower surface of the display panel may have a thickness in the range of about 50 μm to about 200 μm.

[0026] In an embodiment, the preliminary coating material may be provided to cover the entire portion of the lower surface of the display panel.

[0027] In an embodiment, the method may further include forming a functional layer that is directly disposed on the surface of the coating and has a flat surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other features of the embodiments of the present invention will become more apparent by describing the embodiments of the present invention in further detail with reference to the accompanying drawings, in which:

[0029] Figure 1 is a perspective view of a display device according to an embodiment of the present invention;

[0030] Figure 2 is an exploded perspective view of a display device according to an embodiment of the present invention;

[0031] Figure 3 is a cross-sectional view illustrating a partial configuration of a display device according to an embodiment of the present invention;

[0032] Figure 4 is a cross-sectional view of a display panel according to an embodiment of the present invention;

[0033] Figure 5 is a cross-sectional view of a display module according to an embodiment of the present invention;

[0034] Figure 6 is a plan view of a coating according to an embodiment of the present invention;

[0035] Figure 7 A cross-sectional view of a display module according to an embodiment of the present invention;

[0036] Figure 8 A cross-sectional view of a display module according to an embodiment of the present invention;

[0037] Figures 9A to 9E A cross-sectional view for illustrating some processes of a method for manufacturing a display device according to an embodiment of the present invention; and

[0038] Figure 10 A cross-sectional view for illustrating a process of a method for manufacturing a display device according to an embodiment of the present invention. Detailed Description of the Invention

[0039] The present invention will now be described more fully hereinafter with reference to the accompanying drawings in which various embodiments are shown. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.

[0040] In this specification, it will be understood that when an element (or region, layer, or portion, etc.) is referred to as being "on", "connected to", or "coupled to" another element (or region, layer, or portion, etc.), it may be directly disposed on, directly connected to, or directly coupled to the other element (or region, layer, or portion, etc.), or an intervening element may be disposed therebetween.

[0041] The same reference numerals or symbols refer to the same elements throughout. And, for an effective description of the technical content, in the drawings, the proportions and dimensions (e.g., thickness) of the elements are enlarged.

[0042] Although terms such as "first", "second", etc. may be used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present invention, the first element may be referred to as the second element, and similarly, the second element may also be referred to as the first element.

[0043] And, terms such as "below", "under", "above", and "on" may be used to describe the relationship of the elements illustrated in the drawings. It will be understood that these terms have relative concepts and are described based on the orientation depicted in the drawings.

[0044] The terms used in this specification are for the purpose of describing particular embodiments only and are not intended to be limiting. As used herein, "a," "an," and "at least one" do not denote a limitation of quantity and are intended to include both singular and plural references, unless the context clearly indicates otherwise. Thus, a reference to "an element" followed by a reference to "the element" in a claim includes one or more of the elements. For example, "an element" has the same meaning as "at least one element," unless the context clearly indicates otherwise. "At least one" is not to be construed as limited to "a" or "an." "Or" means "and / or." As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0045] It will be understood that when the terms "includes" and / or "including," or "comprises" and / or "comprising" are used in this specification, there is stated the presence of the recited feature, integer, step, operation, element, component, or combination thereof, but there is not excluded the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

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

[0047] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Also, terms (such as those defined in a commonly used dictionary) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein.

[0048] Embodiments are described herein with reference to cross-sectional views that are schematic illustrations of ideal embodiments. As such, variations in the shape of the illustrations due to, for example, manufacturing techniques and / or tolerances are to be expected. Accordingly, the embodiments described herein should not be construed as limited to the specific shapes of the regions as illustrated herein, but should include, for example, shape deviations caused by manufacturing. For example, regions illustrated or described as flat may generally have rough and / or non-linear features. Also, the illustrated sharp corners may be rounded. Thus, the regions illustrated in the figures are schematic in nature, and their shapes are not intended to illustrate the exact shape of the regions and are not intended to limit the scope of the claims.

[0049] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0050] Figure 1 Is a perspective view of a display device DD according to an embodiment of the present invention. Figure 2 Is an exploded perspective view of a display device DD according to an embodiment of the present invention.

[0051] In Figure 1 As an example, an embodiment is illustrated in which the display device DD is implemented as a mobile phone. However, the display device DD is not limited thereto, and may be a small or medium-sized display device (such as a tablet computer, a car navigation system, a game console, a wearable device, or a camera).

[0052] The display device DD can display an image IM through an active region AA-DD. The active region AA-DD may include a flat surface defined by a first direction DR1 and a second direction DR2. The active region AA-DD may further include a curved surface bent from at least one side of the flat surface on a plane defined by the first direction DR1 and the second direction DR2. Figure 1 An embodiment is illustrated in which the display device DD includes two curved surfaces that are bent from both sides of the flat surface defined by the first direction DR1 and the second direction DR2, respectively. However, the shape of the active region AA-DD is not limited thereto. In another embodiment, for example, the active region AA-DD may include only a flat surface, or may further include at least two curved surfaces, for example, four curved surfaces bent from four side surfaces, respectively.

[0053] In Figure 1 And the following drawings, a first direction to a third direction DR1, DR2, and DR3 are illustrated, and the directions indicated by the first direction to the third direction DR1, DR2, and DR3 described herein may have a relative concept, and thus may be changed to other directions.

[0054] In this specification, a first direction DR1 and a second direction DR2 may be orthogonal to each other, and a third direction DR3 may be a normal direction of a plane defined by the first direction DR1 and the second direction DR2. In this specification, the phrase "on a plane" may mean a situation when observed on a plane defined by the first direction DR1 and the second direction DR2, and a thickness direction may mean the third direction DR3, which is a normal direction of a plane defined by the first direction DR1 and the second direction DR2.

[0055] In an embodiment, a display device DD may include an active region AA-DD and a peripheral (or non-active) region NAA-DD adjacent to the active region AA-DD. The active region AA-DD may be a part of a display region AA corresponding to a display panel DP (see Figure 2 ), and the peripheral region NAA-DD may be a part of a non-display region NAA corresponding to the display panel DP (see Figure 2 ).

[0056] The peripheral region NAA-DD as a region for blocking optical signals may be disposed outside the active region AA-DD and surround the active region AA-DD. In an embodiment, the peripheral region NAA-DD may not be disposed on a front surface of the display device DD, but may be disposed on a side surface of the display device DD. In another embodiment, the peripheral region NAA-DD may be omitted.

[0057] Referring to Figure 2 , a display device DD according to an embodiment may include a window member WM, a housing HU, a display module DM, a circuit board DC, and an upper member UM.

[0058] A display device DD according to an embodiment may include a window member WM disposed on a display panel DP. The window member WM provides or defines an outer surface of the display device DD. Although not illustrated, the window member WM may include a base substrate and may further include functional layers (such as an antireflection layer, an anti-fingerprint layer, or a phase control optical layer).

[0059] In a display device DD according to an embodiment, the upper member UM may be disposed below the window member WM and above the display module DM. The upper member UM may include an antireflection layer or an input detection sensor (also referred to as an "input sensor"). The antireflection layer may reduce external light reflectance. The input detection sensor may detect an external input from a user. The upper member UM may further include an adhesive layer that bonds the antireflection layer and the input detection sensor.

[0060] In a display device DD according to an embodiment, the display module DM may be disposed below the upper member UM. The display module DM may include a display panel DP and a coating CM.

[0061] The display panel DP may include a display area AA where an image IM is displayed and a non-display area NAA adjacent to the display area AA. That is, the front surface of the display panel DP may include the display area AA and the non-display area NAA. The display area AA may be an area activated in response to an electrical signal.

[0062] The non-display area NAA may be adjacent to the display area AA. The non-display area NAA may surround the display area AA. In the non-display area NAA, a driving circuit or driving wiring for driving the display area AA, various types of signal lines or pads for supplying an electrical signal to the display area AA, or electronic components, etc. may be provided.

[0063] The display area AA may include a signal transmission area SA and a non-transmission area NSA. The signal transmission area SA may overlap with an electronic module EM, and the non-transmission area NSA may be provided to surround at least a part of the signal transmission area SA. The non-transmission area NSA may correspond to the area of the display panel DP other than the signal transmission area SA.

[0064] In a plane or when observed in a third direction DR3, the signal transmission area SA may overlap with the electronic module EM. The electronic module EM may receive an external input transmitted through the signal transmission area SA or provide an output through the signal transmission area SA. The electronic module EM may be provided under a coating CM. The signal transmission area SA may include a camera sensing area CSA and a sensor sensing area SSA. Under the display panel DP, a camera module CAM may be provided to overlap with the camera sensing area CSA, and a sensor module SM may be provided to overlap with the sensor sensing area SSA. Although not illustrated, according to another embodiment, if necessary, a predetermined opening may be defined in the signal transmission area SA of the display panel DP. Accordingly, a part of the display panel DP may be penetrated or a through hole may be defined.

[0065] Figure 2 An embodiment in which the signal transmission area SA includes the camera sensing area CSA and the sensor sensing area SSA is illustrated, but the number of signal transmission areas SA is not limited thereto. In an embodiment of the display panel DP, a single signal transmission area SA may be defined as a single area or three or more areas. Figure 2 An embodiment in which the signal transmission area SA has a circular shape or a quadrilateral shape is illustrated. However, the shape of the signal transmission area SA is not limited thereto, and various definitions may be made if necessary.

[0066] In a plane or when observed in a third direction DR3, the area of the signal transmission area SA may be smaller than the area of the non-transmission area NSA. The transmittance of the signal transmission area SA may be different from the transmittance of the non-transmission area NSA. The transmittance of the signal transmission area SA may be greater than the transmittance of the non-transmission area NSA.

[0067] In the display panel DP according to an embodiment, a part of a driving circuit or driving wiring for driving pixels (not shown) provided in the signal transmission area SA may be provided in a part of the non-display area NAA or the non-transmission area NSA. Accordingly, the wiring density in the signal transmission area SA may be less than the wiring density in the non-transmission area NSA. However, embodiments of the present invention are not limited thereto, and the wiring density in the signal transmission area SA and the wiring density in the non-transmission area NSA may be substantially the same.

[0068] The display panel DP may include a light-emitting element layer DP-ED (see Figure 4 ), and the light-emitting element layer DP-ED (see Figure 4 ) includes an organic light-emitting element, a quantum dot light-emitting element, a micro light-emitting diode (LED) light-emitting element, or a nano LED light-emitting element, etc. The light-emitting element layer DP-ED (see Figure 4 ) may be configured to substantially generate light for displaying an image.

[0069] The coating CM may be provided under the display panel DP. The coating CM may be a multi-functional member or unit that supports the display panel DP to enhance impact resistance, performs a heat dissipation function of dissipating heat generated in the display panel DP, and performs a light blocking function of blocking light. Holes HH may be defined in the coating CM. The holes HH may be defined in a region of the coating CM corresponding to the electronic module EM. The holes HH may be defined in the coating CM to overlap the signal transmission area SA in a third direction DR3 which is its thickness direction. In an embodiment, the holes HH of the coating CM may be defined as a single hole or multiple holes. The holes HH may include a sensor hole H-S and a camera hole H-C. The sensor hole H-S may correspond to the above-mentioned sensor sensing area SSA, and the camera hole H-C may correspond to the above-mentioned camera sensing area CSA. That is, under the coating CM, the sensor module SM may be provided to overlap the sensor hole H-S, and the camera module CAM may be provided to overlap the camera hole H-C. Details of the coating CM will be described later with reference to Figure 5 description of the coating CM.

[0070] The display device DD may include a circuit board DC connected to the display panel DP. The circuit board DC may include a flexible board CF and a main board MB. The flexible board CF may include an insulating film and conductive wirings mounted on the insulating film. The conductive wirings are connected to the pads PD to electrically connect the circuit board DC to the display panel DP. In another embodiment, the flexible board CF may be omitted, and the main board MB may be directly connected to the display panel DP.

[0071] The main board MB may include signal lines and electronic components not illustrated. The electronic components may be connected to the signal lines to be electrically connected to the display panel DP. The electronic components generate various types of electrical signals, for example, signals for generating an image IM or signals for detecting an external input, or process the detected signals. In an embodiment, the main board MB may be provided in multiple numbers to correspond to each electrical signal for generation and processing, and is not limited to any one embodiment.

[0072] In a display device DD according to an embodiment, the electronic module EM may be an electronic component that outputs or receives an optical signal. In an embodiment, for example, the electronic module EM may include a camera module CAM and a sensor module SM. The camera module CAM may receive external light through a camera sensing area CSA and capture an external image. Also, the sensor module SM may be a sensor that outputs or receives external light through a sensor sensing area SSA, such as a proximity sensor or an infrared light emitting sensor.

[0073] A display device DD according to an embodiment may include a housing HU disposed under a coating CM. The display panel DP and the like may be accommodated inside the housing HU. In a display device DD according to an embodiment, a window member WM and the housing HU may be coupled to each other to constitute the exterior of the display device DD.

[0074] Figure 3 A cross-sectional view for explaining a partial configuration of a display device DD according to an embodiment of the present invention.

[0075] Reference Figure 3 , a display device DD according to an embodiment of the present invention may include a window member WM, an upper member UM, a display panel DP, a circuit board DC, and a coating CM.

[0076] In an embodiment, the window member WM may cover the front surface of the display panel DP. The window member WM may include a window WM-BS and a light blocking pattern WM-BZ. The window WM-BS may be disposed on the display panel DP and cover the display panel DP. The window WM-BS may include a transparent first base layer (such as a glass substrate or a transparent film). The light blocking pattern WM-BZ may be disposed on the window WM-BS and overlap with a peripheral area NAA-DD. The light blocking pattern WM-BZ may have a multi-layer structure. The multi-layer structure of the light blocking pattern WM-BZ may include a color layer and a black light blocking layer. The color layer and the black light blocking layer may be formed by a deposition, printing, or coating process. In an embodiment, the light blocking pattern WM-BZ may be omitted from the window member WM and may not be formed on the window WM-BS either, but may be formed on the upper member UM.

[0077] In an embodiment, the upper member UM may include an anti-reflection layer UM-1 and an input sensor UM-2. The upper member UM may be disposed on the upper surface DP-US of the display panel DP.

[0078] The anti-reflection layer UM-1 may reduce the external light reflectance. The anti-reflection layer UM-1 may include a retarder and / or a polarizer. The anti-reflection layer UM-1 may include a polarizing film or a color filter. The color filter may have a predetermined arrangement. The arrangement of the color filter may be determined in consideration of the color of light emitted from pixels included in the display panel DP. The anti-reflection layer UM-1 may include a dividing layer (not shown) adjacent to the color filter.

[0079] The input sensor UM-2 may include a plurality of sensing electrodes (not shown) for detecting an external input, traces (not shown) connected to the plurality of sensing electrodes, and an inorganic layer and / or an organic layer for insulating / protecting the plurality of sensing electrodes or traces. The input sensor UM-2 may be a capacitive sensor, but is not particularly limited thereto.

[0080] In an embodiment, the input sensor UM-2 may be directly formed on the encapsulation layer ENL (see Figure 4 ) described later during the manufacture of the display panel DP by a continuous process. However, embodiments of the present invention are not limited thereto. The input sensor UM-2 may be manufactured as a panel separate from the display panel DP and then attached to the display panel DP through an adhesive layer. Figure 4

[0081] In an embodiment, an adhesive layer (not shown) may be further disposed between the window member WM and the anti-reflection layer UM-1, and the adhesive layer may be further disposed between the anti-reflection layer UM-1 and the input sensor UM-2. The window member WM, the anti-reflection layer UM-1, and the input sensor UM-2 may be bonded to each other through the adhesive layer, respectively.

[0082] In an embodiment, the circuit board DC may include a flexible board CF and a main board MB. In an embodiment, the flexible board CF may be assembled in a bent state. Accordingly, the main board MB may be disposed on the rear surface of the display panel DP and may be stably accommodated in a space provided by the housing HU (see Figure 2 ). In an embodiment, for example, the flexible board CF may be bent toward the rear surface of the display panel DP and may be disposed under the coating CM. However, embodiments of the present invention are not limited thereto, and in another embodiment, the flexible board CF may be omitted. In such an embodiment, the main board MB may be directly disposed under the coating CM or mounted in the coating CM.

[0083] In an embodiment, the coating CM is disposed below the display panel DP. The coating CM can be directly disposed on the lower surface DP-LS of the display panel DP and in contact with the lower surface DP-LS of the display panel DP. The coating CM can be in contact with the circuit board DC. In an embodiment, for example, the coating CM can be in contact with the main board MB. Details of the coating CM will be described below with reference to Figure 5 Describe the details of the coating CM.

[0084] Figure 4 Is a cross-sectional view of a display panel DP according to an embodiment.

[0085] In an embodiment, the display panel DP includes a base substrate BL, a display circuit layer DP-CL disposed on the base substrate BL, a light-emitting element layer DP-ED, and a packaging layer ENL. The base substrate BL can include a plastic substrate, a glass substrate, a metal substrate, or an organic / inorganic composite substrate, etc. In an embodiment, for example, the base substrate BL can include at least one polyimide layer.

[0086] The display circuit layer DP-CL includes at least one insulating layer, a semiconductor pattern, and a conductive pattern. The insulating layer includes at least one inorganic layer and at least one organic layer. The semiconductor pattern and the conductive pattern can form or define signal lines, a pixel driving circuit, and a scan driving circuit. Additionally, the display circuit layer DP-CL can include a back surface metal layer.

[0087] The light-emitting element layer DP-ED includes display elements, for example, light-emitting elements. In an embodiment, for example, the light-emitting element can be an organic light-emitting element, a quantum dot light-emitting element, a micro LED light-emitting element, or a nano LED light-emitting element. The light-emitting element layer DP-ED can further include an organic layer (such as a pixel defining film).

[0088] The light-emitting element layer DP-ED can be disposed in the display area AA. The non-display area NAA is disposed in the outer periphery of the display area AA and surrounds the display area AA. The light-emitting elements are not arranged in the non-display area NAA.

[0089] The packaging layer ENL can be disposed on the light-emitting element layer DP-ED and cover the light-emitting element layer DP-ED. The packaging layer ENL can be disposed on the display circuit layer DP-CL to seal the light-emitting element layer DP-ED. The packaging layer ENL can be a thin film packaging layer including a plurality of organic thin films and inorganic thin films. The packaging layer ENL can include a thin film packaging layer having a stacked structure of an inorganic layer / organic layer / inorganic layer. The stacked structure of the packaging layer ENL is not particularly limited.

[0090] Figure 5 Is a cross-sectional view of a display module DM (see Figure 2 ) according to an embodiment of the present invention. Figure 5 Is along Figure 2The sectional view of the display module DM (see Figure 2 ) taken along line I-I'.

[0091] Referring to Figure 5 , the display module DM (see Figure 2 ) according to an embodiment of the present invention may include a display panel DP and a coating CM disposed below the display panel DP. The display module DM may be composed of the display panel DP and the coating CM.

[0092] In an embodiment, the coating CM may be directly disposed on the lower surface DP-LS of the display panel DP (i.e., the lower surface of the base substrate BL of the display panel DP (see Figure 4 ). The upper surface CM-US of the coating CM may be in direct contact with the lower surface DP-LS of the display panel DP. In a display device DD (see Figure 1 ) according to an embodiment of the present invention, only the coating CM may be disposed below the display panel DP. That is, the lowermost surface of the display module DM may be defined as the lower surface CM-LS of the coating CM. Accordingly, during the manufacture of the display device DD (see Figure 1 ) according to the embodiment, the thickness of the display device DD (see Figure 1 ) according to the embodiment may be reduced and the components may be simplified, thereby increasing the process efficiency.

[0093] The coating CM includes a base layer BS and a plurality of fillers FP dispersed in the base layer BS, and the base layer BS includes a resin material. The coating CM may be a single layer composed of or defined by the base layer BS and the plurality of fillers FP. The plurality of fillers FP may be fillers dispersed in the base layer BS.

[0094] The coating CM includes the base layer BS and the plurality of fillers FP, and thus may perform various functions within the display device DD (see Figure 1 ). For example, the coating CM may support the display panel DP and disperse the impact applied to the display panel DP, thereby improving the impact resistance. The coating CM may protect the display panel DP (see Figure 1 ) etc. from physical impacts applied from the outside of the display device DD (see Figure 1 ). The coating CM may perform a heat dissipation function of dissipating heat generated from adjacent elements (such as the display panel DP) etc. The coating CM may include a light blocking material to perform a light blocking function. The coating CM may also have an electromagnetic shielding function etc. In such an embodiment, the coating CM as a single layer performs the functions traditionally performed by a plurality of typical functional layers, thereby simplifying the structure of the display device DD (see Figure 1 ) and achieving a thickness reduction. However, the functions of the coating CM are not limited thereto, and depending on the characteristics of the coating CM (such as its thickness and material), the coating CM may perform various functions in the display device DD (see Figure 1) perform other functions additionally therein.

[0095] The base layer BS can be a layer providing a base material in which a variety of fillers FP are dispersed. The base layer BS can include an organic material. The base layer BS can include at least one selected from acrylate polymers, urethane polymers, silicone polymers, and imide polymers. The base layer BS can include a curable resin material. In an embodiment, for example, the base layer BS can include a photocurable resin material. The base layer BS can include a material having a predetermined strength.

[0096] The variety of fillers FP can each include an organic material or an inorganic material. In an embodiment, for example, the variety of fillers FP can each include graphite or metal particles. The variety of fillers FP can include the same material as each other or different materials from each other. The variety of fillers FP can be fillers that perform the same function as each other or different functions from each other respectively. Accordingly, the coating CM can perform a variety of functions (such as support of the display panel DP, heat dissipation of the display device DD (see Figure 1 ).

[0097] The variety of fillers FP can each include a light-transmitting material. In an embodiment where the base layer BS includes a photocurable resin material and the filler FP includes a light-transmitting material, the coating CM can be manufactured by a photocuring method.

[0098] The variety of fillers FP can include a first filler FP1 including a light-blocking material and a second filler FP2 including a material having a thermal conductivity of about 100 watts per meter kelvin (W / m·K) or greater. The first filler FP1 can be a black pigment. The first filler FP1 prevents light heading toward the coating CM from passing through the coating CM, and thus the coating CM can perform a light-blocking function. The second filler FP2 includes a material having a high thermal conductivity, and thus the coating CM can perform a heat dissipation function. The second filler FP2 can include metal particles, carbon nanotubes (CNTs), or graphene having a high thermal conductivity. Due to the first filler FP1 and the second filler FP2, the coating CM can perform a light-blocking function and a heat dissipation function. Accordingly, in such an embodiment, an additional light-blocking layer or heat-dissipating layer can be omitted.

[0099] The coating CM can have an absorbance of about 3.0 or greater. Since the coating CM has an absorbance of about 3.0 or greater, light heading toward the coating CM cannot pass through the coating CM. In a case where the coating CM has an absorbance less than about 3.0, the coating CM cannot be used as a light-blocking layer. The absorbance can mean the absorbance in the ultraviolet-visible light (UV-Vis) range. However, the meaning of the absorbance is not limited thereto.

[0100] Coating CM may have a thermal conductivity of about 100 W / m·K or greater. Because coating CM has a thermal conductivity of about 100 W / m·K or greater, coating CM can function as a heat dissipation layer. Accordingly, in such an embodiment, an additional heat dissipation layer can be omitted, and thus the thickness of display module DM can be reduced. The thermal conductivity can be a value measured at about 25 °C. However, the measurement conditions are not limited thereto.

[0101] Coating CM may have a storage modulus in the range of about 0.01 megapascals (Mpa) to about 1 Mpa. The value of the storage modulus of coating CM can be less than the value of the storage modulus of a typical or conventional support layer provided in display device DD (see Figure 1 ). Accordingly, coating CM can be designed to be softer than a typical or conventional support layer, and thus the stress applied to display panel DP during folding or rolling of display device DD (see Figure 1 ) can be reduced. In the case where coating CM has a storage modulus of less than about 0.01 Mpa, coating CM may not effectively support display panel DP. In the case where coating CM has a storage modulus of greater than about 1 Mpa, the flexibility of coating CM may be reduced, and thus the stress applied to display panel DP during folding or rolling of display device DD (see Figure 1 ) can be increased. The storage modulus can be a value measured at a temperature range of -50 °C to 300 °C and at a frequency of 1 Hz, 10 Hz, or 100 Hz. However, the measurement conditions are not limited thereto

[0102] Coating CM may have a thickness d1 in the range of about 50 micrometers (μm) to about 200 μm. In the case where coating CM has a thickness d1 of less than about 50 μm, a corrugated structure WS may not be properly formed on the lower surface CM-LS of coating CM. This is because the corrugated structure WS of coating CM is formed due to the difference in the curing rate and shrinkage rate between the surface part and the deep part. Details thereof will be described later in the method for manufacturing display device DD (see Figures 9A to 9E described for manufacturing display device DD (see Figure 1 ).

[0103] In the case where coating CM has a thickness d1 greater than about 200 μm, the thickness of display module DM may become too large. In this case, by replacing multiple functional layers with a single coating CM, the thickness of display device DD (see Figure 1 ) may not be substantially reduced. Additionally, in this case, when coating CM becomes too thick, the stress applied to display panel DP during rolling and folding of display device DD (see Figure 1 ) may increase.

[0104] The lower surface (or surface) CM-LS of the coating CM may include an irregular corrugated structure WS, which includes valleys (or curved valleys) (i.e., curved concave portions) VAL and ridges (or curved ridges) (i.e., curved convex portions) CRE. Due to the corrugated structure WS of the lower surface CM-LS of the coating CM, an external impact applied in a direction perpendicular to the coating CM can be dispersed in the horizontal direction. That is, when an impact is applied to the corrugated structure WS in the vertical direction, the micro-deformation of the corrugated structure WS can reduce the amount of the impact, and thus the impact resistance can be greatly improved.

[0105] The valleys VAL may have a shape that is recessed toward the display panel DP. The ridges CRE may have a shape that protrudes in a direction away from the display panel DP. In the corrugated structure WS, the valleys VAL and the ridges CRE may be alternately arranged and extend in the horizontal direction.

[0106] The corrugated structure WS may have a specific thickness TH and wavelength WA. In this case, the thickness TH may mean the height difference between the valleys VAL and the ridges CRE, that is, the thickness difference between the thickest part and the thinnest part of the coating CM. In this case, the wavelength WA may be the distance between the highest points of adjacent ridges CRE. The corrugated structure WS may have an atypical shape on a plane while having a predetermined thickness TH and wavelength WA. The thickness TH and wavelength WA of the corrugated structure WS may vary according to the thickness of the coating CM and the concentration of oxygen exposed during the curing of the coating CM.

[0107] The coating CM may include a first part CPP1 adjacent to the lower surface CM-LS and a second part CPP2 farther from the lower surface CM-LS than the first part CPP1. The first part CPP1 may have a first curing rate, and the second part CPP2 may have a second curing rate greater than the first curing rate. This is because the part adjacent to the surface is not properly cured during the curing of the coating CM due to the surface being exposed to oxygen. Due to the difference in the curing rate, the corrugated structure WS may be formed on the lower surface CM-LS of the coating CM. Details thereof will be described later in the method for manufacturing the display device DD (see Figures 9A to 9E described in Figure 1 ).

[0108] Figure 6 FIG. is a plan view of the coating CM according to an embodiment of the present invention. More specifically, Figure 6 FIG. is a plan view of the lower surface CM-LS of the coating CM when viewed on a plane (see Figure 5 ).

[0109] Refer to Figure 5 and Figure 6, the lower surface CM-LS of the coating CM may have a structure in which ridges CRE protruding in a direction away from the display panel DP and valleys VAL recessed toward the display panel DP are repeatedly provided. However, the shapes of the ridges CRE and valleys VAL may form an irregular and atypical corrugated structure WS without a specific rule.

[0110] Figure 7 is a cross-sectional view of a display module DM (see Figure 2 ) according to an embodiment of the present invention. Hereinafter, components that are the same as or similar to those described with reference to Figure 5 are denoted by the same reference numerals or symbols, and any repeated detailed description thereof will be omitted.

[0111] Reference Figure 7 , in an embodiment, the display module DM (see Figure 2 ) may further include a functional layer TAR including a flat surface. The functional layer TAR may further include a resin material. The functional layer TAR may be in direct contact with the lower surface CM-LS of the coating CM. The functional layer TAR may be formed by applying a resin material to the lower surface CM-LS of the coating CM.

[0112] The functional layer TAR may have a flat surface provided on the corrugated structure WS of the coating CM. Since the corrugated structure WS is flattened by the functional layer TAR, the impact applied to the coating CM is further reduced, and thus the impact resistance can be improved. The functional layer TAR may include a light-transmitting material. The functional layer TAR may include a transparent resin material. The refractive index of the functional layer TAR matches or is substantially the same as that of the corrugated structure WS, and thus the corrugated structure WS can be effectively prevented from being observed from the outside.

[0113] Figure 8 is a cross-sectional view of a display module DM (see Figure 2 ) according to an embodiment of the present invention. Hereinafter, components that are the same as or similar to those described with reference to Figure 5 are denoted by the same reference numerals or symbols, and any repeated detailed description thereof will be omitted.

[0114] Reference Figure 8 , in an embodiment, the display module DM (see Figure 2 ) may further include an adhesive layer AL and a heat dissipation layer HDL. The heat dissipation layer HDL may be provided on the lower surface CM-LS of the coating CM and include a heat dissipation material. The heat dissipation layer HDL may further enhance the heat dissipation function of the coating CM. A metal having a high thermal conductivity or the like may be used as or included in the heat dissipation layer HDL. In an embodiment, for example, the heat dissipation layer HDL may be a copper layer. However, the heat dissipation layer HDL is not limited thereto, and various materials may be used as needed.

[0115] Although not illustrated in Figure 8 , in an embodiment where the display module DM further includes a heat dissipation layer HDL, the second filler FP2 that performs a heat dissipation function may be omitted from the coating CM. The heat dissipation layer HDL may be bonded to the lower surface CM-LS of the coating CM via an adhesive layer AL.

[0116] Figures 9A to 9E Cross-sectional views of some processes of a method for manufacturing a display device DD (see Figure 1 ) according to an embodiment of the present invention are illustrated. Hereinafter, components that are the same as or similar to the components described with reference to Figures 1 to 8 are denoted by the same reference numerals or symbols, and any repeated detailed description thereof will be omitted.

[0117] Referring to Figure 9A , in a method for manufacturing a display device DD (see Figure 1 ) according to an embodiment of the present invention, a display panel DP may be provided or prepared, and then a preliminary coating material P-CM may be formed or provided on the lower surface DP-LS of the display panel DP. The preliminary coating material P-CM may include a base resin P-BS including a photocurable resin material and a plurality of fillers FP dispersed in the base resin P-BS. The plurality of fillers FP may include a first filler FP1 including a light-blocking material and performing a light-blocking function and a second filler FP2 including a material having a thermal conductivity of about 100 W / m·K and performing a heat dissipation function. The preliminary coating material P-CM may be entirely provided on the lower surface DP-LS of the display panel DP (or provided to cover the entire portion of the lower surface DP-LS of the display panel DP).

[0118] The preliminary coating material P-CM may have a thickness in the range of about 50 μm to about 200 μm. If the preliminary coating material P-CM has a thickness less than about 50 μm, the corrugated structure WS (see Figure 9C ) of the coating CM (see Figure 9C ) may not be formed. If the preliminary coating material P-CM has a thickness greater than about 200 μm, the thickness of the display module DM (see Figure 2 ) may become too large.

[0119] Referring to Figure 9B , the preliminary coating material P-CM may be cured to form a first preliminary coating P-BS2 having a first curing rate and a second preliminary coating P-BS1 that is closer to the display panel DP than the first preliminary coating P-BS2 and has a second curing rate greater than the first curing rate (primary curing process).

[0120] In the primary curing process, the preliminary coating material P-CM may be irradiated with light LS. The light LS may be ultraviolet light. In this process, the surface of the preliminary coating material P-CM may be exposed to oxygen. The concentration of oxygen may be about 50 parts per million (50 ppm) or more. In the case where the surface of the preliminary coating material P-CM is exposed to oxygen, the curing may proceed slowly even when irradiated with light LS, compared with the case where the curing is performed in the absence of oxygen. The portion adjacent to the surface of the preliminary coating material P-CM and more actively in contact with oxygen than the deep portion of the preliminary coating material P-CM may be cured slowly. The curing rate of the second preliminary coating layer P-BS1 away from the surface of the preliminary coating material P-CM may be higher than the curing rate of the first preliminary coating layer P-BS2 adjacent to the surface of the preliminary coating material P-CM.

[0121] The difference in curing rate between the first preliminary coating layer P-BS2 and the second preliminary coating layer P-BS1 may result in a difference in shrinkage rate between the first preliminary coating layer P-BS2 and the second preliminary coating layer P-BS1, and thus the coating layer CM (see Figure 9C ) surface CM-LS (see Figure 9C ) can have a corrugated structure WS (see Figure 9C That is, the shrinkage rate of the second preliminary coating layer P-BS1 having a higher degree of curing may be greater than the shrinkage rate of the first preliminary coating layer P-BS2 having a lower degree of curing, and thus the difference in shrinkage rate between the first preliminary coating layer P-BS2 and the second preliminary coating layer P-BS1 may be greater than the shrinkage rate of the first preliminary coating layer P-BS2 and the second preliminary coating layer P-BS1. Figure 9C ) on the surface of the corrugated structure WS (see Figure 9C ).

[0122] As the thickness of the preliminary coating material P-CM increases, the difference in curing rate between the surface portion and the deep portion of the preliminary coating material P-CM increases, and thus a large corrugated structure WS may be formed. In addition, the difference in curing rate between the surface portion and the deep portion of the preliminary coating material P-CM may be caused only when the concentration of oxygen exposed to the surface of the preliminary coating material P-CM is about 50 ppm or more. The shape of the corrugated structure WS can be adjusted by controlling the thickness of the preliminary coating material P-CM and the concentration of oxygen exposed to the surface of the preliminary coating material P-CM.

[0123] refer to Figure 9B and Figure 9C, the curable first preliminary coating P-BS2 and the second preliminary coating P-BS1 can be cured to form a coating CM (secondary curing process) including an irregular corrugated structure WS on the surface CM-LS. The coating CM can be directly disposed on the lower surface DP-LS of the display panel DP, and can have an irregular corrugated structure WS on the surface CM-LS of the coating CM. The corrugated structure WS includes valleys VAL recessed toward the display panel DP and ridges CRE protruding in a direction away from the display panel DP. During curing, the surface of the preliminary coating material P-CM can be exposed to oxygen. Only when the concentration of oxygen exposed to the surface of the preliminary coating material P-CM is about 50 ppm or greater, can an irregular corrugated structure WS be formed on the surface CM-LS of the coating CM.

[0124] Reference Figure 9D and Figure 9E , a preliminary functional layer P-TAR including a resin material can be further applied on the surface CM-LS of the coating CM. The applied preliminary functional layer P-TAR can be cured by irradiating with light LS, and then a functional layer TAR can be formed. The functional layer TAR can be directly disposed on the surface CM-LS of the coating CM and includes a flat surface. The functional layer TAR can include a light-transmitting resin material.

[0125] Figure 10 To illustrate a cross-sectional view of the process of a method for manufacturing a display device DD (see Figure 1 ).

[0126] Reference Figure 10 , in an embodiment, a heat dissipation layer HDL can be formed on the surface CM-LS of the coating CM. An adhesive layer AL can be formed on the surface CM-LS of the coating CM, and a heat dissipation layer HDL including a heat dissipation material can be formed on the adhesive layer AL.

[0127] The present invention should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the present invention to those skilled in the art.

[0128] Although the present invention has been specifically shown and described with reference to its embodiments, those of ordinary skill in the art will understand that various changes in form and details can be made therein without departing from the spirit or scope of the present invention as defined by the claims.

Claims

1. A display device, comprising: A display panel including a display area and a non-display area; as well as A single-layer coating is directly disposed on the lower surface of the display panel, The coating layer comprises a base layer and a plurality of fillers dispersed in the base layer, the base layer comprises a resin material, and The surface of the coating layer has an irregular corrugated structure including curved valleys recessed toward the display panel and curved ridges protruding in a direction away from the display panel.

2. The display device of claim 1 , wherein a first portion of the coating adjacent to the surface has a first curing rate, and A second portion of the coating that is further away from the surface than the first portion has a second cure rate that is greater than the first cure rate. The display device according to claim 1 , wherein the coating layer has an absorbance of 3.0 or more. The display device according to claim 1 , wherein the coating layer has a storage modulus in a range of 0.01 MPa to 1 MPa. 5 . The display device according to claim 1 , wherein the coating layer has a thickness in the range of 50 μm to 200 μm. The display device according to claim 1 , wherein the coating layer has a thermal conductivity of 100 W / m·K or more. The display device according to claim 1 , wherein the base layer comprises a photocurable resin material.

8. The display device according to claim 1, wherein the plurality of fillers comprises: a first filler material comprising a light blocking material; as well as A second filler includes a material having a thermal conductivity of 100 W / m·K or more. 9 . The display device according to claim 1 , further comprising a functional layer directly disposed on the surface of the coating layer, having one flat surface and comprising a light-transmitting material. 10 . The display device according to claim 1 , further comprising a heat dissipation layer provided on the surface of the coating layer and comprising a heat dissipation material.

11. The display device according to claim 1, further comprising an electronic module disposed under the coating layer, The display panel includes a signal transmission area and a non-transmission area adjacent to the signal transmission area. The electronic module overlaps the signal transmission area, and The coating overlaps the non-transmitting region.

12. The display device according to claim 1, further comprising: a window disposed on the display panel and covering the display panel; and A light blocking pattern is disposed on the window and overlaps the non-display area.

13. A method for manufacturing a display device, the method comprising: providing a display panel including a display area and a non-display area; providing a preliminary coating material on a lower surface of the display panel; as well as curing the preliminary coating material to form a coating layer, the coating layer being directly disposed on the lower surface of the display panel and having an irregular corrugated structure on a surface of the coating layer, the corrugated structure comprising curved valleys recessed toward the display panel and curved ridges protruding in a direction away from the display panel, Wherein, when the preliminary coating material is cured to form the coating layer, the surface of the preliminary coating material is exposed to oxygen.

14. The method according to claim 13, wherein the preliminary coating material comprises: A base resin comprising a photocurable resin material; as well as A plurality of fillers are dispersed in the base resin. 15 . The method according to claim 13 , wherein a concentration of the oxygen to which the surface of the preliminary coating material is exposed is 50 ppm or more when the preliminary coating material is cured to form the coating layer.

16. The method of claim 13, wherein curing the preliminary coating material to form the coating comprises: Performing primary curing on the preliminary coating material to form a first preliminary coating layer having a first curing rate and a second preliminary coating layer that is adjacent to the display panel than the first preliminary coating layer and has a second curing rate greater than the first curing rate; as well as The first preliminary coating layer and the second preliminary coating layer are subjected to secondary curing to form the coating layer having the irregular corrugated structure on the surface thereof.

17. The method of claim 14, wherein the plurality of fillers comprises: a first filler material comprising a light blocking material; as well as A second filler includes a material having a thermal conductivity of 100 W / m·K or more. 18 . The method of claim 13 , wherein the preliminary coating material disposed on the lower surface of the display panel has a thickness in a range of 50 μm to 200 μm.

19. The method according to claim 13, wherein the preliminary coating material is provided to cover an entire portion of the lower surface of the display panel.

20. The method according to claim 13, further comprising forming a functional layer, the functional layer being directly disposed on the surface of the coating layer and having a flat surface.

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