Display device

Abstract

A display device according to one embodiment comprises a substrate including a plurality of grooves, a metal layer located on one side of the substrate, a light-emitting element layer located on the metal layer, and a heat dissipation layer located on the other side of the substrate, wherein the heat dissipation layer is in contact with the metal layer inside the grooves.

Description

Technology Field

[0001] The present disclosure relates to a display device, and more specifically, to a display device with improved heat dissipation performance. Background Technology

[0002] Recently, the importance of Flat Panel Displays (FPDs) has been increasing alongside the development of multimedia. Consequently, various types of flat displays, such as Liquid Crystal Displays (LCDs) and Light Emitting Display Devices, are being commercialized.

[0003] Among these, light-emitting displays are replacing the conventionally widely used liquid crystal displays. Since light-emitting displays generate light themselves to display images, they do not require a backlight unit as a component, unlike liquid crystal displays. Therefore, light-emitting displays are not only advantageous for reducing thickness compared to liquid crystal displays but also possess superior response characteristics, leading to a gradual expansion of their application as next-generation display devices.

[0004] Meanwhile, since the light-emitting layer of the light-emitting diode in the light-emitting display device is made of an organic material that is sensitive to heat, it can easily degrade due to heat generated from the display panel and driving circuit board, which can shorten its lifespan; accordingly, there is a need to dissipate the heat generated inside the light-emitting display device to the outside. The problem to be solved

[0005] The embodiments are intended to provide a display device with excellent heat dissipation performance. means of solving the problem

[0006] A display device according to one embodiment comprises a substrate including a plurality of grooves, a metal layer located on one side of the substrate, a light-emitting element layer located on the metal layer, and a heat dissipation layer located on the other side of the substrate, wherein the heat dissipation layer is in contact with the metal layer inside the grooves.

[0007] The heat dissipation layer comprises a first portion located inside the groove, a substrate, and a second portion located above the first portion, and the first portion and the second portion may be connected to each other.

[0008] The above substrate may include glass.

[0009] The heat dissipation layer comprises a polymer resin and heat dissipation particles, and the heat dissipation particles may be one or more of copper, carbon nanotubes (CNT), graphene oxide (GO), and graphite.

[0010] The content of the heat dissipation particles in the heat dissipation layer may be 1% to 80% by weight.

[0011] The above polymer resin may include one or more of acrylate, polyurethane, and polyethylene in its structure.

[0012] The ratio of the area where grooves are formed to the total area of ​​the substrate may be 5% to 90%.

[0013] The above substrate includes a banding region and a non-banding region, and a groove may be formed in the banding region.

[0014] The above groove can be formed linearly.

[0015] The above groove may have a polygonal or circular shape.

[0016] The metal layer comprises chromium or titanium, and the metal layer may overlap with the front surface of the substrate.

[0017] A display device according to another embodiment comprises a substrate having a plurality of grooves, a light-emitting element layer located on one side of the substrate, and a heat dissipation layer located on the other side of the substrate, wherein the heat dissipation layer comprises a first portion located inside the groove and a second portion located on the substrate and the first portion.

[0018] The thickness of the substrate in the area where the groove is located may be thinner than the thickness of the area where the groove is not located.

[0019] The ratio of the area where the groove is formed to the total area of ​​the substrate may be 5% to 90%.

[0020] A display device according to another embodiment comprises a substrate, a light-emitting element layer located on one side of the substrate, a pattern layer located on the other side of the substrate and including a plurality of patterns spaced apart from each other, and a heat dissipation layer located on the pattern layer, wherein the heat dissipation layer includes a first portion located between the patterns and in contact with the side of the pattern and a second portion located on the pattern layer.

[0021] The above substrate may include polyimide.

[0022] The above pattern layer may include a polymer resin.

[0023] The first part and the second part can be connected to each other.

[0024] A method for manufacturing a display device according to one embodiment includes the steps of forming a metal layer on one side of a substrate, positioning a mask on the other side of the substrate, etching the substrate using the mask to form a groove, forming a heat dissipation layer first within the groove, and forming a heat dissipation layer secondarily on the substrate filled with the groove.

[0025] A method for manufacturing a display device according to another embodiment includes the steps of forming a pattern layer with a plurality of spaced patterns using a polymer resin on one surface of a substrate, forming a heat dissipation layer between the plurality of spaced patterns in a first step, and forming a heat dissipation layer in a second step on the pattern layer with the spaced areas filled. Effects of the invention

[0026] According to the embodiments, a display device with excellent heat dissipation performance is provided. Brief explanation of the drawing

[0027] FIG. 1 briefly illustrates a cross-section of a display device according to the present embodiment. FIG. 2 shows the same cross-section as FIG. 1 for a display device according to another embodiment. Figure 3 illustrates a metal layer, a substrate, and a heat dissipation layer in a foldable display device. FIG. 4 shows a cross-section identical to FIG. 1 for another embodiment. FIG. 5 illustrates a region in which a groove is formed in a source substrate comprising a plurality of substrates. FIG. 6 illustrates a groove in a substrate for another embodiment. FIG. 7 illustrates a groove in a substrate for another embodiment. FIG. 8 illustrates a groove in a substrate for another embodiment. FIG. 9 illustrates a groove in a substrate for another embodiment. FIGS. 10 to 13 are process cross-sectional views showing a process for manufacturing the display device of FIG. 1. FIGS. 14 to 16 are process cross-sectional views showing a process for manufacturing the display device of FIG. 2. Specific details for implementing the invention

[0028] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0029] To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0030] Furthermore, the size and thickness of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and thus the present invention is not necessarily limited to what is illustrated. Thicknesses have been enlarged in the drawings to clearly represent various layers and regions. Additionally, for convenience of explanation, the thickness of some layers and regions has been exaggerated in the drawings.

[0031] Furthermore, when a part such as a layer, membrane, region, or plate is said to be "on" or "on" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Also, being "on" or "on" a reference part means being located above or below the reference part, and does not necessarily mean being located "on" or "on" in the direction opposite to gravity.

[0032] Furthermore, throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0033] Additionally, throughout the specification, "planar" means when the subject part is viewed from above, and "cross-sectional" means when the cross-section obtained by vertically cutting the subject part is viewed from the side.

[0034] Then, a display device according to one embodiment will be described below with reference to the drawings.

[0035] FIG. 1 briefly illustrates a cross-section of a display device according to the present embodiment. Referring to FIG. 1, the display device according to the present embodiment includes a substrate (110), a metal layer (120) located on one side of the substrate, an element layer (300) located on the metal layer, and a heat dissipation layer (200) located on the other side of the substrate (110). The element layer (300) may include a plurality of thin-film transistors, a plurality of light-emitting elements connected thereto, and an encapsulation layer covering them, and is a layer that displays an image by light emission.

[0036] Referring to FIG. 1, a plurality of grooves (111) may be located in the substrate (110). A heat dissipation layer (200) is located while filling the inside of the grooves (111) and may come into contact with a metal layer (120).

[0037] Since the device layer (300) emits heat during operation, a heat dissipation layer is required to release this heat to the outside of the display device. If the heat generated in the device layer (300) is not properly released to the outside, the transistors included in the device layer (300) may be damaged or malfunction due to overheating of the device layer (300).

[0038] In this embodiment, the substrate (110) may include glass. Since glass has low thermal conductivity, the substrate (110) including glass may not effectively dissipate heat.

[0039] However, in the case of the display device according to the present embodiment, a plurality of grooves (111) are located on the substrate (110), and a heat dissipation layer (200) is located within the grooves (111). The heat dissipation layer (200) is located inside the grooves (111) of the substrate (110) and on the front surface of the substrate (110), and can effectively dissipate heat generated from the element layer (300). The heat dissipation layer (200) may include a first part (210) located within the grooves (111) and a second part (220) located outside the grooves (111). The first part (210) and the second part (220) may be integrally connected to each other.

[0040] The heat dissipation layer (200) may be made of a polymer resin containing heat dissipation particles. Specifically, the polymer resin of the heat dissipation layer (200) may be an acrylate-based resin. An acrylate-based resin refers to a resin that contains acrylate within its structure. Additionally, the acrylate-based resin may further include structures such as polyurethane and polyethylene. Polyurethane and polyethylene serve as auxiliary materials that allow the heat dissipation layer (200) to have elasticity, thereby protecting the display device without the need for a separate cushion layer. The resin of the heat dissipation layer (200) may be a resin that hardens upon UV irradiation.

[0041] The heat dissipation particles may be one or more of copper, carbon nanotubes (CNT), graphene oxide (GO), and graphite. These particles may be nanoparticles having a nano-sized size. The content of the heat dissipation particles within the heat dissipation layer (200) may be 1 weight% to 80 weight%. If the content of the heat dissipation particles is less than 1 weight%, it may not have sufficient heat dissipation performance. Additionally, if the content of the heat dissipation particles exceeds 80 weight%, the heat dissipation layer (200) and the substrate (110) may not adhere well.

[0042] The groove (111) may be formed on the front surface of the display device or only in the bending area of ​​the display device. For example, the area of ​​the region where the groove (111) is formed in the substrate (110) of the display device may be 5% to 90%. If the area where the groove (111) is formed is less than 5%, heat dissipation may not be effectively achieved, and if the area where the groove (111) is formed exceeds 90%, the strength of the substrate (110) may be weakened, and the display device may not be effectively supported.

[0043] In FIG. 1, the metal layer (120) located on the substrate (110) can function as an etch stopper during the etching process of the groove (111) of the substrate (110). That is, the metal layer (120) can prevent the device layer (300) from being etched during the etching process for forming the groove (111) on the substrate (110). The metal layer (120) may include chromium or titanium. Since the metal layer (120) is also made of metal and has excellent thermal conductivity, it can effectively transfer heat generated from the device layer (300) to the heat dissipation layer (200).

[0044] In FIG. 1, a display device is described in which the substrate (110) includes glass, but the substrate (110) may include polyimide instead of glass. FIG. 2 shows a cross-section identical to FIG. 1 for a display device according to another embodiment.

[0045] Referring to FIG. 2, in this embodiment, the substrate (110) comprises polyimide rather than glass. The substrate (110) comprising polyimide may not include a separate groove (111). Instead, a pattern layer (150) may be located on one side of the substrate (110). The pattern layer (150) may include a plurality of patterns spaced apart from each other as in FIG. 1. A heat dissipation layer (200) is located on the spaced-apart area of ​​the pattern layer (150) and on the pattern layer (150). The heat dissipation layer (200) may include a first portion (210) located on the spaced-apart area of ​​the pattern layer (150) and a second portion (220) located on the pattern layer (150). The first portion (210) and the second portion (220) may be integrally connected to each other.

[0046] That is, in the case of the embodiment of FIG. 2, instead of a groove being formed in the substrate (110), a pattern layer (150) is additionally positioned, and a heat dissipation layer (200) is positioned between the pattern layers (150). The description of other components is the same as in FIG. 1 and is therefore omitted.

[0047] In FIG. 2, the pattern layer (150) can be formed by an inkjet method using a polymer resin. Specifically, the pattern layer (150) may include a polysiloxane-based acrylate. However, the material of the pattern layer (150) is not limited thereto. The pattern layer (150) may include various resins that can be formed by an inkjet method.

[0048] The heat dissipation layer (200) is located in the spaced-out area and front of the pattern layer (150) and can receive heat generated from the device layer (300).

[0049] Although FIGS. 1 and 2 illustrate a configuration in which a groove (111) or a pattern layer (150) is formed over the entire display device, the groove (111) and the pattern layer (150) may be formed only in a part of the display device.

[0050] FIG. 3 illustrates only the metal layer (120), substrate (110), and heat dissipation layer (200) of a foldable display device. As shown in FIG. 3, the substrate (110) may include a groove (111) located in the bending region (BA), and may not include a groove (111) in the non-bending region (NBA). Thus, when the substrate (110) includes a groove (111) in the bending region (BA), it can be bent easily. That is, a substrate (110) containing glass is not easy to bend, but when a groove (111) is included in the bending region (NA) as in FIG. 3, it can be bent easily. The heat dissipation layer (200) filled in the groove (111) includes polyurethane or polyethylene and has elasticity, so it is easy to bend.

[0051] However, this is merely one example, and grooves may also be formed in the non-banding area (NBA). If the display device is a rollable display, grooves may be formed across the entire rolling area.

[0052] In FIGS. 1 and 3, the heat dissipation layer (200) is shown to be in direct contact with the metal layer (120) in the groove (111) of the substrate (110), but the heat dissipation layer (200) may not be in direct contact with the metal layer (120). FIG. 4 shows a cross-section identical to FIG. 1 for another embodiment. Referring to FIG. 4, in the display device according to the present embodiment, the substrate (110) includes a groove (112) instead of a groove. It differs in that the groove (111) in FIG. 1 penetrates the substrate (110), but the groove (112) in FIG. 4 does not penetrate the substrate (110). That is, the groove (112) refers to an area where the substrate (110) is not completely etched and remains partially intact.

[0053] In the embodiment of FIG. 4, the heat dissipation layer (200) includes a first portion (210) located within the groove (112) and a second portion (220) covering the front surface of the substrate (110). In this case as well, heat dissipation performance can be improved similarly to the embodiment of FIG. 1. Since the thickness of the substrate (110) is thin in the area where the groove (112) is located, heat can be transferred to the heat dissipation layer (200) better than in the area where the groove (112) is not located. The description of other components is the same as in FIG. 1 and is therefore omitted.

[0054] FIG. 5 illustrates an area in which a groove (111) is formed in a source substrate (1000) comprising a plurality of substrates (110). As shown in FIG. 5, the groove (111) may be formed parallel in one direction. However, this is merely an example, and the groove (111) may be formed in various shapes.

[0055] FIG. 6 illustrates the grooves (111) of the substrate (110) according to another embodiment. Referring to FIG. 6, the display device according to the present embodiment has the grooves (111) of the substrate (110) formed in a grid shape. In this case, heat can be released more quickly than when the grooves (111) are located in one direction.

[0056] FIG. 7 illustrates a groove (111) of a substrate (110) according to another embodiment. Referring to FIG. 7, the groove (111) of the substrate (110) in the display device according to the present embodiment may be positioned diagonally. At this time, the formation direction of the groove (111) may vary depending on the bending direction of the display device.

[0057] FIG. 8 illustrates a groove (111) of a substrate (110) according to another embodiment. Referring to FIG. 8, the groove (111) of the substrate (110) in the display device according to the present embodiment may be positioned in an X-shape.

[0058] FIG. 9 illustrates a groove (111) of a substrate (110) for another embodiment. Referring to FIG. 9, the display device according to the present embodiment has a groove (111) of the substrate (110) formed as a through plate in a portion of the area. The groove (111) of the substrate (110) may be formed to overlap with a part of the display device where a lot of heat is generated. For example, it may be formed to overlap with a part of the display device where a lot of wiring passes or a part where a pad is located. When the groove (111) is formed in a part where a lot of heat is generated in this way, heat can be effectively dissipated. In FIG. 9, the groove (111) is illustrated as a polygon, but it may be circular or elliptical.

[0059] Various shapes of the grooves (111) have been described through FIGS. 5 to 9, but this is merely an example and is not limited thereto. The grooves (111) may occupy 5% to 90% of the total area of ​​the substrate (110), and their shapes may vary.

[0060] Then, a method for manufacturing a display device according to the present embodiment will be described below with reference to the drawings. FIGS. 10 to 13 are cross-sectional process views showing a process for manufacturing the display device of FIG. 1.

[0061] Referring to FIG. 10, a mask (700) is placed on one side of a substrate (110). At this time, a metal layer (120) may be placed on the other side of the substrate (110). The metal layer (120) may include copper or titanium and may function as an etch stopper during the subsequent etching process. A light-emitting element layer (170) may be placed on the metal layer (120). The light-emitting element layer (170) may include a plurality of thin-film transistors and light-emitting elements connected thereto. An encapsulation layer (180) may be placed on the light-emitting element layer (170). The encapsulation layer (180) may include a structure in which an organic film and an inorganic film are alternately stacked and may protect the light-emitting element layer (170) from external moisture. A touch sensing layer (190) may be placed on the encapsulation layer (180). The touch sensing layer (190) may be omitted depending on the embodiment.

[0062] The mask (700) can be formed from an organic material. Specifically, the mask (700) can be formed by coating it with epoxy resin. At this time, the thickness of the mask (700) can be 10 μm to 900 μm. The mask (700) is the part that is etched first when the substrate (110) is subsequently etched, and its thickness can be appropriately adjusted according to the thickness of the substrate (110) and the depth of the groove (111) to be formed.

[0063] Referring to FIG. 11, the substrate (110) is etched. At this time, the etching can be performed as a wet etch using an etching solution such as hydrofluoric acid. In the area where the mask (700) was located, the mask (700) is etched first, and in the area where the mask (700) was not located, the groove (111) is formed. In FIG. 10, since the metal layer (120) functions as an etch stopper, only the substrate (110) is etched, and the metal layer (120) or other layers above the metal layer (120) are not etched.

[0064] Next, referring to FIG. 12, a heat dissipation layer (200) is first coated on the groove (111) to form a first portion (210). The description of the heat dissipation layer (200) is as described above. That is, the heat dissipation layer (200) may be made of a resin containing heat dissipation particles. The resin may be an acrylate-based resin, and the heat dissipation particles may be one or more of copper, carbon nanotubes (CNT), graphene oxide (GO), and graphite.

[0065] The groove (111) is filled by the primary coating of the heat dissipation layer (200), and one side of the substrate (110) becomes flat.

[0066] Next, referring to FIG. 13, a second portion (220) is formed by coating the heat dissipation layer (200) a second time. At this time, the second portion (220) of the heat dissipation layer (200) is evenly coated on the front surface of the substrate (110) and the groove (111) filled with the heat dissipation layer (200). At this time, the second portion (220) of the heat dissipation layer (200) is connected to the previously formed first portion (210) while in contact with it.

[0067] FIGS. 14 to 16 are process cross-sectional views showing a process for manufacturing the display device of FIG. 2.

[0068] Referring to FIG. 14, a pattern layer (150) is formed on one side of a substrate (110). The description of the light-emitting element layer (170), the encapsulation layer (180), and the touch sensing layer (190) located on the other side of the substrate (110) is the same as in FIG. 9 and is therefore omitted.

[0069] The pattern layer (150) can be formed using an inkjet method with a resin. Specifically, the pattern layer (150) can be formed with a polysiloxane-based acrylate and can be formed using an inkjet method. As shown in FIG. 14, a plurality of pattern layers (150) can be formed spaced apart from each other.

[0070] Referring to FIG. 15, a heat dissipation layer (200) is first coated in a spaced area of ​​the pattern layer (150) to form a first portion (210). The description of the heat dissipation layer (200) is as described above. That is, the heat dissipation layer (200) may be made of a resin containing heat dissipation particles. The resin may be an acrylate-based resin, and the heat dissipation particles may be one or more of copper, carbon nanotubes (CNT), graphene oxide (GO), and graphite.

[0071] The spaced area of ​​the pattern layer (150) is filled by the primary coating of the heat dissipation layer (200), and the pattern layer (150) can have a flat surface.

[0072] Referring to FIG. 16, a second portion (220) is formed by coating the heat dissipation layer (200) a second time. At this time, the second portion (220) of the heat dissipation layer (200) is evenly coated on the front surface of the pattern layer (150) and the first coated heat dissipation layer (200). At this time, the second portion (220) is connected to the first portion (210) while in contact with it.

[0074] Although embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention. Explanation of the symbols

[0076] 1000: Original board 110: Board 111: Home 112: Groove 120: Metal layer 150: Pattern layer 170: Light-emitting element layer 180: Encapsulation layer 190: Touch sensing layer 200: Heat dissipation layer 210: Part 1 220: Part 2 300: Device layer BA: Banding region NBA: Non-banding zone

Claims

Claim 1 A display device comprising: a substrate including a plurality of grooves; a metal layer located on one side of the substrate; a light-emitting element layer located on the metal layer; and a heat dissipation layer located on the other side of the substrate, wherein the heat dissipation layer contacts the metal layer within the grooves, and each of the plurality of grooves is formed linearly on a planar surface. Claim 2 In claim 1, the heat dissipation layer comprises a first portion located inside the groove; a second portion located above the substrate and the first portion, and the first portion and the second portion are connected to each other in a display device. Claim 3 In claim 1, the substrate is a display device comprising glass. Claim 4 A display device according to claim 1, wherein the heat dissipation layer comprises a polymer resin and heat dissipation particles, and the heat dissipation particles are one or more of copper, carbon nanotubes (CNT), graphene oxide (GO), and graphite. Claim 5 A display device according to claim 4, wherein the content of the heat dissipation particles in the heat dissipation layer is 1% to 80% by weight. Claim 6 In paragraph 4, the above polymer resin is a display device comprising one or more of acrylate, polyurethane, and polyethylene in its structure. Claim 7 A display device according to claim 1, wherein the ratio of the area where grooves are formed to the total area of ​​the substrate is 5% to 90%. Claim 8 A display device according to claim 1, wherein the substrate includes a banding region and a non-banding region, and a groove is formed in the banding region. Claim 9 delete Claim 10 delete Claim 11 In claim 1, the metal layer comprises chromium or titanium, and the metal layer overlaps the front surface of the substrate in a display device. Claim 12 A display device comprising: a substrate including a plurality of grooves; a light-emitting element layer located on one side of the substrate; and a heat dissipation layer located on the other side of the substrate, wherein the heat dissipation layer includes a first portion located inside the groove and a second portion located on the substrate and the first portion, and each of the plurality of grooves is formed linearly on a plane. Claim 13 In paragraph 12, a display device in which the thickness of the substrate in the area where the groove is located is thinner than the thickness of the area where the groove is not located. Claim 14 A display device according to claim 12, wherein the ratio of the area where the groove is formed to the total area of ​​the substrate is 5% to 90%. Claim 15 A display device comprising: a substrate; a light-emitting element layer located on one side of the substrate; a pattern layer located on the other side of the substrate and including a plurality of patterns spaced apart from each other; and a heat dissipation layer located on the pattern layer, wherein the heat dissipation layer includes a first portion located between the patterns and in contact with the side of the pattern and a second portion located on the pattern layer, and wherein each of the plurality of patterns is formed linearly on a plane. Claim 16 In paragraph 15, the substrate is a display device comprising polyimide. Claim 17 In paragraph 15, the pattern layer comprises a polymer resin and is a display device. Claim 18 In paragraph 15, the first part and the second part are connected to each other in a display device. Claim 19 A method for manufacturing a display device comprising: a step of forming a metal layer on one side of a substrate; a step of positioning a mask on another side of a substrate; a step of etching the substrate using the mask to form a groove; a step of forming a heat dissipation layer first within the groove; and a step of forming a heat dissipation layer secondarily on the substrate filled with the groove, wherein the groove is formed linearly on a planar surface. Claim 20 A method for manufacturing a display device comprising: a step of forming a pattern layer with a plurality of spaced patterns using a polymer resin on one surface of a substrate; a step of first forming a heat dissipation layer between the plurality of spaced patterns; and a step of secondarily forming a heat dissipation layer on the pattern layer with the spaced area filled, wherein each of the plurality of patterns is formed linearly on a planar surface.

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