KR20220165946A - Heat insulation sheet for display light source, heat insulated display light source and display device comprising the same - Google Patents

Abstract

Provided is an insulation sheet for a display light source. According to an embodiment of the present invention, an insulation sheet for a display light source is provided on the opposite surface to a circuit board mounting surface on which a plurality of LED elements constituting a light source of a display are mounted, spaced at predetermined intervals, to block heat generated from the plurality of LED elements from being transferred in the direction perpendicular to the opposite surface. Accordingly, the insulation sheet can minimize the transfer of received heat in the perpendicular direction while reducing the level of heat in the plurality of LED elements, and is thus advantageous in minimizing or preventing heat transfer in an undesirable direction and/or of an undesirable amount.

Description

Heat insulation sheet for display light source, heat insulation light source module including the same, heat insulation backlight unit and display device

The present invention relates to a heat insulating sheet, and more particularly, to a heat insulating sheet for a display light source, a heat insulating light source module including the same, a backlight unit, and a display device.

Due to the increase in the integration of IC circuits due to the advancement of the industry, hybrid packages and multi-modules, sealed integrated circuits such as LEDs, complex structures of electronic devices, and the trend of slim, miniaturized and high performance, the heat generation is increasing in various electronic parts.

Accordingly, it has emerged as an important task to effectively dissipate a lot of heat generated in a narrow space in an electronic device to prevent malfunction and damage of electronic components.

On the other hand, considering the performance and durability of the electronic device, the heat generated by the electronic device should be emitted to the outside, but this causes a problem that a lot of heat is sensed in the vicinity of the electronic device's housing or electronic device.

In particular, as electronic devices are becoming slimmer or smaller in recent years, the gap between various parts and housings in electronic devices is almost disappearing. As the temperature of the housing or its surroundings is getting worse, there are frequent cases in which the user who comes into contact with the electronic device feels uncomfortable or is mistaken for an abnormal operation of the electronic device.

A typical example of such an electronic device is a display device. Display devices are still being mass-produced with low-cost models, but on the other hand, as large-sized and high-performance are promoted, they are designed to have more pixels in a limited area. The number of light sources used is increasing.

As an example of this trend, in the case of a liquid crystal display device having a backlight unit using recently commercialized mini-LED elements as a light source, more than 20,000 mini-LED elements are mounted on the backlight unit, and the luminance due to the large number of LED elements is It is known as an advantage to increase the contrast ratio according to the individual control of the LED elements in the backlight unit. However, the problem of heat generation due to the 20,000 or more LED elements is serious, and as a result, a lot of heat is emitted to the rear surface of the liquid crystal display device, causing discomfort to users or increasing the risk of burns to users.

In addition, as the distance between the display device housing and the display part is minimized and a high-brightness LED device is being developed, the problem of high heat transferred from the backlight unit to the housing due to the LED device is expected to be further intensified.

Registered Patent Publication No. 10-2059126

The present invention has been devised in view of the above points, and heat is transferred from a plurality of LED elements, which are heating elements, to lower the heat generation level of the LED elements while minimizing the transfer of the received heat in the vertical direction, so that the heat is transferred to the upper part of the sheet. An object of the present invention is to provide a heat insulating sheet capable of minimizing or preventing conduction or radiation, and for example, to provide a heat insulating sheet suitable for application to a display light source.

According to the first embodiment of the present invention in order to solve the above problems, a plurality of LED elements constituting a light source of a display are provided on the opposite surface of the mounting surface of the circuit board mounted at a predetermined interval, so that the plurality of LED elements A heat insulating sheet for a display light source to block the transfer of generated heat in a direction perpendicular to the opposite surface, as a member attached to the opposite surface of the circuit board mounting surface, having an area larger than the mounting area of each LED element. A heat spreading member including a substrate for forming a hot spot and an adhesive layer disposed on both sides of the substrate, disposed on the heat spreading member, and including a first surface perpendicular to the thickness direction and a second surface facing the heat spreading member. And, the heat transferred toward the first surface adjacent to the heat spreading member is moved from the first surface to the second surface in a thickness direction and a surface direction perpendicular to the thickness direction to lower the temperature of the LED element. Heat is preferentially moved in the surface direction rather than in the thickness direction to minimize heat transfer from the second surface toward the direction perpendicular thereto, while minimizing overlap due to surface direction spreading of heat transferred from a plurality of LED elements and receiving A heat insulating member, which is a graphite sheet having a thickness set in consideration of the distance between LED elements and the amount of heat generated by the LED elements, and a protective member disposed on the second surface of the heat insulating member to transfer heat in the thickness direction and accumulate inside as much as possible It provides a heat insulating sheet for a display light source comprising.

According to an embodiment of the present invention, the heat insulating member may include at least one graphite sheet selected from natural graphite sheets and artificial graphite sheets.

In addition, the heat insulating member may have a thickness of 20 to 500 μm.

In addition, the heat insulating member may be natural graphite having a thickness of 90 μm or more.

In addition, the substrate may be metal foil or artificial graphite.

In addition, the plane-direction thermal conductivity of the substrate may be smaller than that of the graphite sheet.

In addition, the length and width of each of the protection member and the heat spreading member are formed to be greater than the length and width of the heat insulating member so that four sides parallel to the thickness direction of the heat insulating member are sealed through the protection member and the heat spreading member. can

In addition, according to the second embodiment of the present invention, a plurality of LED elements constituting a light source of the display are provided on the opposite side of the mounting surface of the circuit board mounted at a predetermined interval, so that the heat generated from the plurality of LED elements A heat insulating sheet for a display light source to block transmission in a direction perpendicular to the opposite surface, as a member attached to the opposite surface of the circuit board mounting surface, to form a hot spot with an area larger than the mounting area of each LED element A heat spreading member including a substrate for a substrate and a first adhesive layer disposed on both sides of the substrate, disposed on the heat spreading member, including a first surface perpendicular to the thickness direction and a second surface facing the heat spreading member, The heat transferred toward the first surface adjacent to the heat spreading member is moved from the first surface to the second surface in the thickness direction and in the direction perpendicular to the thickness direction to lower the temperature of the LED element, Heat is preferentially moved in the surface direction to minimize heat transfer from the second surface toward the direction perpendicular thereto, while minimizing overlap due to surface-direction spreading of heat transferred from a plurality of LED elements and maximizing the transfer of heat. A heat insulating member, which is a graphite sheet having a thickness set in consideration of the distance between LED elements and the amount of heat generated by the LED elements, in order to transmit in the thickness direction and accumulate inside, a member attached to the heat insulating member, and heat transferred from the heat insulating member to the soup A thermal insulation sheet for a display light source comprising a heat accumulation member including a metal substrate for reding and accumulation therein and a second adhesive layer disposed on both sides of the metal substrate, and a protective member attached to one adhesive layer of the heat accumulation member. to provide.

According to an embodiment of the present invention, the heat insulating member may include at least one graphite sheet selected from natural graphite sheets and artificial graphite sheets.

In addition, the heat insulating member may have a thickness of 20 to 500 μm.

In addition, the heat insulating member may be natural graphite having a thickness of 90 μm or more.

In addition, the substrate may be metal foil or artificial graphite.

In addition, the surface direction thermal conductivity of any one or both of the substrate and the metal substrate may be smaller than that of the graphite sheet.

In addition, the substrate and the metal substrate each independently include at least one of an aluminum foil and a copper foil, and the graphite sheet may be a natural graphite sheet.

In addition, the substrate and the metal substrate may each independently have a thickness of 7 to 75 μm, and the first adhesive layer and the second adhesive layer may each independently have a thickness of 7 to 55 μm.

In addition, the length and width of each of the protection member, the heat accumulation member, and the heat spreading member are determined so that the four sides parallel to the thickness direction of the heat insulating member are sealed through the protection member, the heat accumulation member, and the heat spreading member. It can be formed larger than the length and width of.

In addition, in the first embodiment and the second embodiment of the present invention, the graphite sheet is to minimize overlapping with each other after heat transferred from one LED element and another LED element disposed adjacent to it is transferred in the plane direction, respectively A ratio (a/b) of thermal conductivity (a) in the plane direction to thermal conductivity (b) in the thickness direction may be 100 or less.

In addition, the protective member is a protective film containing at least one selected from the group consisting of polyimide, polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), and an adhesive layer for fixing to the heat insulating member is provided on one surface of the protective film. can include more.

In addition, the protective member may have a thickness of 50 to 200 μm.

In addition, the heat spreading member may further include a release film on a surface opposite to one surface in contact with the heat insulating member.

In addition, the present invention provides a circuit board, a plurality of LED elements mounted on one surface of the circuit board at a predetermined distance from each other, and a display according to the present invention arranged so that an adhesive member is positioned on the surface opposite to the one surface of the circuit board. Provided is a heat insulating light source module including a heat insulating sheet for a light source.

Also, the plurality of LED devices may be mini LED devices or micro LED devices.

In addition, one sheet or several sheets of the heat insulating sheet for the display light source may be disposed to cover the opposite surface corresponding to the positions of the plurality of LED elements.

In addition, the present invention provides an adiabatic light source module according to the present invention and an adiabatic backlight unit including a plurality of optical sheets disposed on a light exit surface of the light source module.

According to an embodiment of the present invention, a lower case accommodating part or all of the side surface of the heat insulating light source module and one surface of the heat insulating sheet in the heat insulating light source module, wherein an air layer is formed between the heat insulating sheet and the lower case. may be spaced apart.

In addition, the present invention provides a liquid crystal display device having a heat insulating backlight unit according to the present invention and a liquid crystal display panel disposed on a light exit surface of the heat insulating backlight unit.

In addition, the present invention provides a light emitting display device including the adiabatic light source module according to the present invention.

According to an embodiment of the present invention, the LED element included in the adiabatic light source module is an LED element emitting white, UV, or blue light, and further includes a color conversion unit disposed on a path of light emitted from the adiabatic light source module. can do.

Alternatively, the plurality of LED elements included in the adiabatic light source module may include LED elements emitting red, green, and blue light.

The heat insulating sheet according to the present invention can receive heat generated from a plurality of LED elements used as display light sources and reduce the heat generation level of the LED elements while minimizing the transfer of the received heat in the vertical direction, so that it can be directed in an unwanted direction and/or Alternatively, as it is advantageous to minimize or prevent the transfer of heat in an amount, it is very suitable for blocking heat generated from a plurality of LED elements from being transferred to the housing. In addition, the heat insulating sheet according to an embodiment of the present invention can prevent dust that may occur due to damage or destruction of the inner layer of the heat insulating sheet from scattering, thereby preventing malfunction or damage to the display device due to dust. It can be widely applied to all kinds of display devices.

1 to 3b are schematic cross-sectional views of various embodiments of a heat insulating sheet according to a first embodiment of the present invention;
4 and 5 are cross-sectional schematic views of various embodiments of a heat insulating sheet according to a second embodiment of the present invention;
6 is a perspective view of a heat insulating light source module employing a heat insulating sheet according to an embodiment of the present invention;
7 and 8 are cross-sectional schematic diagrams showing the movement path of heat transferred from a plurality of LED elements, which are heating elements, in a cross section along the XX' boundary line and the Y-Y' boundary line of FIG. 6;
9 and 10 are exploded perspective views of a heat insulating light source module according to various embodiments of the present invention, and are views showing that the heat insulating sheet is provided by being divided into a plurality of sheets;
11 is an exploded perspective view of an adiabatic backlight unit according to an embodiment of the present invention;
12 is an exploded perspective view of a liquid crystal display device according to an embodiment of the present invention, and
13 is a photograph of a circuit board on which a micro LED used in an experimental example of the present invention is mounted.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. This invention may be embodied in many different forms and is not limited to the embodiments set forth herein. In order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and the same reference numerals are added to the same or similar components throughout the specification.

Insulation sheet according to the present invention is provided on the opposite surface of a mounting surface of a circuit board on which a plurality of LED elements constituting a light source of a display are mounted at predetermined intervals, so that heat generated from the plurality of LED elements is perpendicular to the opposite surface. It is a heat insulation sheet for display light sources to block transmission in one direction.

Referring to FIG. 1, the heat insulating sheet 101 according to the first embodiment of the present invention includes a heat insulating member 110 including a first surface perpendicular to the thickness direction and a second surface facing the first surface, A protection member 130 provided on the second surface of the heat insulating member 110 and a heat spreading member 120 provided on the first surface of the heat insulating member 110 are included.

The heat insulating member 110 moves the heat transferred toward the first surface through the heat spreading member 120 adjacent to the LED element in the thickness direction toward the second surface from the first surface and in the surface direction perpendicular to the thickness direction. To express a heat dissipation effect of lowering the temperature of the LED element, but to move heat preferentially in the surface direction rather than in the thickness direction, thereby minimizing heat transfer from the second surface toward the direction perpendicular thereto. At the same time, , For this purpose, the heat insulating member 110 is implemented as a graphite sheet.

Describing the heat insulating mechanism of the heat insulating sheet 101 in detail, the heat reaching the first surface of the heat insulating member 110 from the plurality of LED elements, which are hot spots, through the heat spreading member 120 is perpendicular to the thickness direction. Due to the thermal conductivity of the heat insulating member 110 that is predominantly expressed in the surface direction, more heat is moved in the surface direction than in the thickness direction until the heat capacity of the heat insulating member 110 is saturated. This heat conduction tendency minimizes or prevents heat transfer from the second surface of the heat insulating sheet 100 toward the direction perpendicular thereto by minimizing heat movement from the first surface of the heat insulating member 110 in the thickness direction toward the second surface. It exhibits a heat dissipation effect that reduces the temperature of the LED element for the LED element, which is a heating element, while expressing an insulation effect that

In addition, the heat insulating member 110 minimizes overlap due to surface-direction spreading of heat transferred from the plurality of LED elements, which are hot spots, and transfers the heat received in the thickness direction as much as possible and accumulates the heat in the heat insulating member. It has a thickness set in consideration of the calorific value of the LED element, and through this, the heat insulating sheet can achieve a minimum increase in thickness for improving the heat insulating effect, and the use of an excessively thick graphite sheet is prevented, so a backlight unit equipped with a heat insulating sheet It is advantageous to create a spaced space in which an air layer is formed between the heat insulating sheet and the lower case, and as the heat insulation effect due to the air layer increases, transfer of heat from the backlight unit to the lower case can be minimized.

Referring to FIG. 7, the heat superposition according to the surface-direction spreading of the heat transferred from the plurality of LED elements will be described in detail, the first LED element 221, the second LED element 222, and the third LED element 223 The heat generated from ) reaches the heat spreading member 232 via the circuit board 210, and the heat transferred from the substrate 232a within the heat spreading member 232 is primarily spread in the plane direction. This forms a hot spot with an area larger than the mounting area of the LED element, and a portion of the heat is spread in the plane direction while the remaining heat is transmitted in the vertical direction to reach the first surface of the heat insulating member 231. The heat reaching the heat insulating member 231 spreads more rapidly in the surface direction than in the thickness direction due to heat conduction characteristics that are superior to the surface direction than the thickness direction of the heat insulating member 231 . At this time, in the case of the heat insulating member 231, which is a natural graphite sheet, the ratio of the thermal conductivity in the surface direction to the thermal conductivity in the thickness direction is smaller than that of the artificial graphite sheet. As the movement occurs appropriately, the remaining heat is spread in the plane direction, resulting in a plane-direction spreading (H _xy1 ) of the heat derived from the first LED element 221 and the plane of the heat derived from the second LED element 222. The overlap (A) between directional spreading (H _xy2 ) may be minimized. However, as heat moves in the thickness direction at an appropriate level (H _z ), when the thickness of the heat insulating member 231 is thin, the heat capacity of the heat insulating member 231 is reached in a very short time, so that the heat radiation and heat insulation effect is no longer achieved Since it may be difficult to do so, the heat insulating member 231 may have an appropriate thickness to have a sufficient heat capacity in consideration of the distance between LED elements and the amount of heat generated by the LED elements, and the substrate 232a also has an appropriate thickness so that the heat insulating member 231 It can help keep the insulation effect and exert the heat dissipation effect.

At this time, the thickness of the heat insulating member (110,231) may be set in the range of 20 to 500㎛, for example, if the thickness is less than 20㎛, the time to express the heat insulation effect for a lot of heat generated from a plurality of LED elements is shortened enough It may be difficult to express the insulation effect. In addition, if the thickness exceeds 500 μm, the thermal capacity increases, which is advantageous in improving the heat dissipation effect of the LED device and the insulation effect due to the insulation sheet, but in the case of an artificial graphite sheet, it is not easy to manufacture with such a thickness. In addition, in the case of the natural graphite sheet, the thermal conductivity in the thickness direction can be significantly reduced. As a result, the heat conduction in the plane direction is relatively more dominant, and the heat derived from each adjacent LED element is transferred to the plane direction, resulting in more overlapping. It occurs quickly, and as the overlapped heat is not properly transferred from the first surface to the second surface of the heat insulating member 110, the heat generated from the LED element is not smoothly moved and the heat dissipation performance of the LED element may be reduced. . In addition, damage such as cracks may occur in the heat insulating member when applied to a surface having a curvature or step, and the damage may reduce heat radiation and/or heat insulation effect. In addition, due to scattering of dust generated by the damage, there is a risk of causing electrical shorts to nearby electric and electronic components. In addition, there is a concern that peeling and lifting may occur at interfaces between various members constituting the insulating sheet.

The heat insulating member 110 or 231 is implemented as a graphite sheet, and may be a single graphite sheet or a plurality of graphite sheets stacked. In this case, when the heat insulating member 110 or 231 is made of a single graphite sheet, the thermal conductivity of the heat insulating member 110 or 231 may be that of a single graphite sheet. However, when the heat insulating members 110 and 231 are in the form of stacking several graphite sheets or include other layers such as adhesive layers in addition to the graphite sheets, the heat conduction characteristics of the heat insulating members 110 and 231 described above are satisfied as the entire heat insulating member combined. it's free if you do

According to one embodiment of the present invention, the graphite sheet, which is the heat insulating member 110, has a thickness to minimize overlapping with each other after heat transferred from one LED element and each of the other LED elements disposed adjacent to it is transferred in the plane direction, respectively. The ratio (a/b) of the thermal conductivity (a) in the plane direction to the directional thermal conductivity (b) is 100 or less, in another example, 90 or less, 80 or less, 70 or less, 60 or less, 50 or less, or 40 or less. can In addition, the ratio (a/b) of the thermal conductivity (a) in the plane direction to the thermal conductivity (b) in the thickness direction may be 20 or more, in another example, 30 or more. can be advantageous

In addition, the graphite sheet may specifically include a natural graphite sheet, an artificial graphite sheet, and/or a multilayer graphene sheet. However, in order to conduct or radiate heat from the second surface of the heat insulating member to the upper direction perpendicular to the surface while receiving the heat generated from the plurality of LED elements rapidly and moving in the thickness direction at an appropriate speed and in an appropriate amount, a graphite sheet The graphite sheet needs to be thicker than a predetermined thickness while the ratio between the thermal conductivity in the thickness direction and the thermal conductivity in the plane direction is appropriate. However, in the case of an artificial graphite sheet or a multi-layer graphene sheet, the thermal conductivity in the plane direction is too large compared to the thermal conductivity in the thickness direction, so the heat received from the plurality of LEDs spreads in the plane direction and quickly reaches thermal overlap, whereas, for example, a certain thickness For example, it is not easy to manufacture a thickness exceeding 50 μm, or 60 μm, 70 μm or 80 μm, and even if it can be manufactured, the unit price is very high and it is difficult to use it. Can be difficult to hold. To explain this in more detail with reference to FIG. 7 , when an artificial graphite sheet is used as a heat insulating member, the thermal conductivity in the thickness direction is too small compared to the surface direction, and as a result, in the heat insulating member 231 in the thickness direction Since the movement of the heat is very small, most of the heat is spread in the plane direction. In this case, the plane direction spreading (H _xy1 ) of the heat derived from the first LED element 221 and the heat derived from the second LED element 222 Overlapping (A) can occur at a very fast time between face-direction spreading (H _xy2 ). When the overlap of heat in the surface direction within the heat insulating member 231 increases, the heat insulating member 231 is difficult to accept heat from the heat spreading member 232 any longer, whereas the amount of heat moving in the thickness direction is small, so that the LED elements 221,222,223 It may be difficult to continuously receive generated heat, so that it may be difficult to achieve a desired level of heat dissipation effect.

Preferably, the graphite sheet may include a natural graphite sheet. In the case of the natural graphite, commercially available graphite or graphite referred to as natural graphite may be used without limitation, and thus a detailed description thereof is omitted in the present invention.

In addition, when a natural graphite sheet is used as a heat insulating member, the thickness of the heat insulating member is preferably 90 μm or more, for example, 300 μm or less. When the thickness exceeds 300 μm, the heat dissipation effect may deteriorate.

Next, the heat spreading members 120 and 232 disposed on the first surface side of the above-described heat insulating members 110 and 231 will be described. The heat spreading members 120 and 232 are members attached to the surface opposite to the mounting surface of the circuit board, and include the substrates 122 and 232a and the substrates 122 and 232a for forming a hotspot with an area larger than the mounting area of each LED device. It is a double-sided adhesive member including adhesive layers 121 and 123 on both sides.

The heat spreading members 120 and 232 are important members in terms of heat dissipation/insulation performance and reliability of the insulation sheet.

First, in terms of reliability, the heat spreading members 120 and 232 are members located closest to the hot spot among the members in the insulation sheets 101 and 230, and the insulation sheet must be stably attached to one surface of the circuit board in a high-temperature attachment environment, It is necessary to maintain a stable attachment state even on an attachment surface with a curvature or step difference. When the base material 122, 232a is provided, the attachment state is stably maintained against a high temperature and uneven attachment surface in preparation for a case consisting only of an adhesive layer. advantageous to do

In addition, as will be described later, the heat insulating sheets 101 and 230 include a graphite sheet having excellent electrical conductivity as the heat insulating member 110 and 231 , and scattering of dust from the graphite sheet prevents the device from being dispersed in the electrical and electronic devices provided with the heat insulating sheets 110 and 230 . Electrical reliability that does not affect the device is important because it may cause malfunction or failure. To this end, it is preferable that the four sides of the heat insulating members 110 and 231 are sealed so as to be surrounded, as shown in FIGS. 2 to 3B. However, it is difficult to form the offset structure as illustrated using only the adhesive layer, and it may be advantageous to stably maintain the offset structure even under high temperature conditions through the use of the substrates 122 and 232a.

Next, in terms of heat dissipation/insulation performance, it is advantageous to improve heat dissipation/insulation performance when the substrate 232a on the heat spreading member 232 can form a hot spot with an area larger than the mounting area of each LED element. Do. Referring to FIG. 8 , heat (H) of the LED element 224, which is a hot spot due to the thermal conductivity of the substrate 232a, is primarily transferred to the heat spreading member 232 before being transferred to the heat insulating member 231. It may be moved in a plane direction perpendicular to the thickness direction of the base material 232a. At this time, the area of the hot spot formed on the substrate 232a based on the heat insulating member 231 (S ₂ ) is larger than the mounting area (S ₁ ) of the LED element, and thereby the heat insulating member ( 231) The heat reaching the first surface can be transferred faster and more in the direction perpendicular to the thickness direction of the heat insulating member 231, and is relatively transferred in the thickness direction from the first surface to the second surface. Calories may be further reduced. As a result, heat can be transferred more quickly and more from the LED element 224, so that the heat dissipation effect is improved, while the heat transferred from the second surface of the insulating sheet 230 toward the direction perpendicular to the second surface is further reduced. Therefore, an improved insulation effect can be expressed.

In addition, the substrates 122 and 232a may use, for example, a conductive polymer film, a metal foil, an artificial graphite sheet, etc. When a polymer film is used as a substrate, such as a conductive polymer film, wrinkles are caused by high heat transmitted from a plurality of LED devices. As a result, there is a risk of lifting or peeling at the interface between the attaching surface and the heat spreading member 120 or between the heat spreading member 120 and the heat insulating member 110, and thus reliability at high temperature may be lowered. Preferably, metal foil or an artificial graphite sheet may be used as the substrates 122 and 232a. However, in the case of the artificial graphite sheet, there is a significant difference between the thermal conductivity in the thickness direction and the thermal conductivity in the plane direction, so heat is temporarily spread quickly, but it is difficult to finally achieve a sufficient heat dissipation effect. It is not easy to form, and when forming the opcene structure, a separate protective film for sealing the base material, which is an artificial graphite sheet, must be further provided, and considering the long-term maintenance aspect of the offset structure, the base material is better than using metal foil. can be advantageous

As the metal foil, what is commonly referred to as metal foil in the art may be used without limitation, and may be, for example, rolled foil, artificial foil, or electrolytic foil. In addition, the material of the metal foil is any one of copper foil, aluminum foil, silver foil, nickel foil and gold foil, or an alloy containing two or more of these, two or more of these are mixed or two of them are laminated in separate layers It may be a metal foil. For example, when the graphite sheet is a natural graphite sheet, it may include at least one of a copper foil and an aluminum foil, and more preferably, considering the thermal conductivity of the graphite sheet in the plane direction in terms of the heat dissipation / insulation effect of the insulation sheet, the surface direction It may be advantageous to select a metal foil with low thermal conductivity. Specifically, the thermal conductivity of copper foil is greater than that of aluminum foil. If the thermal conductivity of the graphite sheet in the plane direction is smaller than that of the copper foil but greater than the thermal conductivity of the aluminum foil, aluminum foil is used rather than copper foil as the metal foil. The use case may be superior in heat dissipation and insulation effect, and through these results, it can be seen that the substrate in the heat spreading member does not achieve greater heat dissipation and insulation effect simply because the thermal conductivity is excellent.

Therefore, in order to achieve a sufficient effect of heat dissipation and insulation performance, which is the purpose of the present invention, the thermal conductivity in the plane direction of the substrates 122 and 232a may be smaller than the thermal conductivity in the plane direction of the graphite sheet serving as the heat insulating member 110 and 231.

In addition, as described above, the substrates 122 and 232a must have a predetermined thermal conductivity in the plane direction in order to form a hotspot with an area larger than the mounting area of the LED device, for example, 100 W/m K or more, preferably may be greater than or equal to 200 W/m·K.

In addition, the substrates 122 and 232a minimize overlapping due to surface-direction spreading of heat transferred from a plurality of LED devices and accumulate the heat transferred as much as possible in the thickness direction, the distance between LED devices, the amount of heat generated by the LED devices, and the heat insulation. It may have a thickness set in consideration of the thickness of the member. For example, the substrates 122 and 232a may have a thickness of 7 to 75 μm, preferably 10 to 70 μm. If the thickness of the substrate (122,232a) is less than 7㎛, the desired level of heat dissipation characteristics cannot be expressed and tearing may occur, and if the thickness exceeds 75㎛, it is difficult to thin the insulation sheet and the flexibility is lowered Depending on the bending, interlayer lifting and peeling may occur, which may reduce reliability.

In addition, the substrates 122 and 232a may have a predetermined surface roughness by forming irregularities on the surface in order to improve adhesion characteristics with the adhesive layer disposed on both surfaces, but is not limited thereto.

On the substrates 122 and 232a described above, adhesive layers 121 and 123 are provided for attaching the heat insulating sheet to the adhering surface and fixing the heat insulating members 110 and 231 described above. As the adhesive layers 121 and 123, any adhesive layer commonly used in the art may be used without limitation, and preferably acrylic resin, urethane resin, epoxy resin, silicone rubber, acrylic rubber, carboxyl nitrile elastomer, phenoxy and polyimide It may be formed of an adhesive layer forming composition comprising an adhesive component having at least one selected from the group consisting of resins, more preferably an acrylic resin, and even more preferably an acrylic resin having heat resistance. In addition, the adhesive layer forming composition may further include a curing agent when the adhesive component is a curable resin, and may further include additives such as a curing accelerator depending on the purpose. The curing agent can be used without limitation as long as it is a curing agent commonly used in the art, preferably an epoxy-based curing agent, a diisocyanate-based curing agent, a secondary amine-based curing agent, a tertiary amine-based curing agent, a melamine-based curing agent, an isocyanate-based curing agent It may include at least one selected from the group consisting of a curing agent and a phenol-based curing agent, more preferably an epoxy-based curing agent.

In addition, the adhesive layer may further include a known heat radiation filler.

In addition, the adhesive layer may have a thickness of 7 to 55 μm, preferably 10 to 50 μm. If the thickness of the adhesive layer is less than 7 μm, interlayer adhesion may be reduced, and if the thickness exceeds 55 μm, it is not preferable in terms of thinning, and considering the limited thickness of the heat insulating sheet 101, the heat insulating members 110 and 231 and As the thickness of the substrates 122 and 232a becomes relatively thin, heat dissipation and/or insulation properties may deteriorate.

Next, a protective member 130 is provided on the opposite surface of the heat spreading members 120 and 232 disposed on the heat insulating members 110 and 231 .

The protective member 130 serves to physically and chemically protect the insulating sheet 100 . The protective member 130 may be employed without limitation in the case of the protective member 130 of a conventional sheet. For example, the protective member 130 includes a protective layer 131, and the protective layer 131 may be an inorganic film, a nanofiber web, or a laminated inorganic film on a nanofiber web. In the case of the heat insulating sheet 100 shown in FIG. 1, an inorganic porous film is provided as the protective layer 131. Unlike this, when a nanofiber web is provided as a protective member, a plurality of nanofiber webs are provided with a protective function. It has the advantage of being able to express the thermal insulation effect in the vertical direction through the pores of the

The inorganic porous film may be a film containing at least one selected from the group consisting of polyimide, polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). In addition, the nanofiber web may be a nanofiber web formed of a known material such as urethane-based, fluorine-based, or polyacrylonitrile. The nanofiber web may have a diameter of 1 μm or less, but is not limited thereto.

The protective layer 131 may have a thickness of 10 to 60 μm, preferably 13 to 45 μm, and more specifically, 20 to 30 μm. If the thickness is less than 10 μm, protective performance such as abrasion resistance may be deteriorated, and if the thickness exceeds 60 μm, it is undesirable in terms of thinning and flexibility may be deteriorated, which may cause delamination.

Meanwhile, the protective member 130 may further include an adhesive layer 132 to be fixed on the heat insulating member 110 . The adhesive layer 132 provided on the protective member 130 is the same as the description of the adhesive layer provided on the heat spreading members 120 and 232 described above, so a detailed description thereof will be omitted. It may be configured the same as or different from the adhesive layer.

In addition, it improves the adhesion characteristics on the adhering surface having a curvature or step, prevents separation between layers in the insulation sheet, and prevents scattering of dust that may occur due to breakage of the insulation member 110, which may occur at any time. To do this, an offset structure may be formed as shown in FIGS. 2 to 3B. Specifically, the heat insulating sheet 102 includes a protective member 130 and a heat spreading member so that four sides parallel to the thickness direction of the heat insulating member 110 can be sealed through the protective member 130 and the heat spreading member 120. (120) Each length and width may be larger than each length and width of the heat insulating member 110 by a predetermined size (a). Meanwhile, the length and width of each of the heat insulating member 110, the protective member 130, and the heat spreading member 120 may be appropriately changed in consideration of the size of the LED device, the area of the backlight unit, and the desired heat insulating performance. . On the other hand, in terms of the shape forming the offset structure, the offset structure shown in FIG. 3B may be more excellent in reliability compared to the offset structure shown in FIG. 3A.

Next, the heat insulating sheets 103 and 104 according to the second embodiment of the present invention will be described with reference to FIGS. 4 and 5 . Compared to the heat insulating sheet 101 according to the first embodiment shown in FIG. 1, the heat insulating sheets 103 and 104 according to the second embodiment have a heat accumulating member 140 between the heat insulating member 110 and the protective member 130'. There is a difference in further disposing, and the description of the heat spreading member 120, the heat insulating member 110, and the protective member 130' provided in the heat insulating sheets 103 and 104 is the heat insulating sheet according to the first embodiment ( 101,102) is the same as the description.

Focusing on the differences, the distance between LED elements and the amount of heat generated by the LED elements are minimized in order to minimize overlap due to surface-direction spreading of heat transferred from a plurality of LED elements, and to transfer and accumulate the heat received in the thickness direction as much as possible. Although the thicknesses of the heat insulating member 110 and the base material 122 are set in consideration, in the second embodiment, the heat insulating member 110 in the heat insulating sheets 103 and 104, the base material 122 in the heat spreading member 120, and heat accumulation The thickness of the metal substrate 142 in the member 140 may be set.

In addition, since the heat accumulating member 140 is disposed on the heat insulating member 110, the heat accumulating member 140 receives the heat reaching the second surface of the heat insulating member 110 and accumulates the heat therein, thereby improving heat dissipation. And it is possible to achieve an insulation effect.

The heat accumulation member 140 includes a metal substrate 142 for spreading and internally accumulating heat transferred from the heat insulating member 110 and second adhesive layers 141 and 143 disposed on both sides of the metal substrate 142. include

The heat transferred from the heat insulating member 110 is spread in the direction of the surface of the metal substrate 142 of the heat accumulating member 140, transferred in the thickness direction, and accumulated inside, thereby further improving the heat insulating performance and uniformity regardless of the point. It can be advantageous to achieve an insulating performance. The metal substrate 142 may be used without limitation in the case of a substrate made of a known metal material, and may be, for example, rolled foil, artificial foil, or electrolytic foil. In addition, the material of the metal substrate 142 is any one of copper foil, aluminum foil, silver foil, nickel foil, and gold foil, or an alloy containing two or more of these, two or more of these are mixed, or two or more are each layer It may be made of laminated metal foil. For example, when the graphite sheet is a natural graphite sheet, the metal substrate may include at least one of copper foil and aluminum foil. It may be advantageous to select a metal substrate having a smaller plane direction thermal conductivity. Specifically, the thermal conductivity of the copper foil is greater than that of the aluminum foil. If the thermal conductivity of the selected graphite sheet in the plane direction is smaller than that of the copper foil but greater than the thermal conductivity of the aluminum foil, aluminum rather than using copper foil as a metal substrate The case of using foil may be superior in heat dissipation and insulation effect, and through these results, it can be seen that a greater insulation effect cannot be achieved simply because the metal substrate has excellent thermal conductivity.

Therefore, in order to achieve desired heat dissipation and insulation effects, it is preferable to select one or both of the substrate and the metal substrate having a smaller thermal conductivity in the plane direction than the thermal conductivity in the plane direction of the graphite sheet.

As the second adhesive layers 141 and 143, any adhesive layer commonly used in the art may be used without limitation, and preferably, acrylic resin, urethane resin, epoxy resin, silicone rubber, acrylic rubber, carboxyl nitrile elastomer, phenoxy and It may be formed of an adhesive layer forming composition including an adhesive component having at least one selected from the group consisting of polyimide resin, more preferably an acrylic resin, and even more preferably an acrylic resin having heat resistance. In addition, the adhesive layer forming composition may further include a curing agent when the adhesive component is a curable resin, and may further include additives such as a curing accelerator depending on the purpose. The curing agent can be used without limitation as long as it is a curing agent commonly used in the art, preferably an epoxy-based curing agent, a diisocyanate-based curing agent, a secondary amine-based curing agent, a tertiary amine-based curing agent, a melamine-based curing agent, an isocyanate-based curing agent It may include at least one selected from the group consisting of a curing agent and a phenol-based curing agent, more preferably an epoxy-based curing agent.

In addition, the second adhesive layers 141 and 143 may further include a known heat radiation filler.

In addition, the second adhesive layers 141 and 143 may have a thickness of 7 to 55 μm, preferably 10 to 50 μm. If the thickness of the second adhesive layer is less than 7 μm, the interlayer adhesive strength may decrease, and if the thickness exceeds 55 μm, it is not preferable in terms of thinning, and considering the limited thickness of the heat insulating sheets 103 and 104, the heat insulating member 110 As the thickness of other members such as ) becomes relatively thin, heat dissipation and/or insulation properties may deteriorate.

The above-described heat insulation sheets 101, 102, 102', 103, and 104 according to an embodiment of the present invention may be implemented as an insulation light source module for a display. 6 to 8, the adiabatic light source module 200 includes a circuit board 210, a plurality of LED elements 220 mounted on one surface of the circuit board 210 at predetermined intervals from each other, and It is implemented by including the above-described heat insulating sheet 230 for a display light source disposed so that an adhesive member is positioned on the opposite side of one side of the circuit board.

As shown in FIG. 5 , the plurality of LED elements 220 may be arranged in a checkered pattern to implement a direct type light source. Also, the plurality of LED devices 220 may be mini LED devices or micro LED devices. The mini LED device and the micro LED device may be implemented with a length of each side exceeding 100 μm to 500 μm. In addition, the micro LED device may be implemented with a length of each side of 100 μm or less. In addition, the LED elements 211 , 212 , 213 , and 214 may be known LED materials and structures. The LED elements 211, 212, 213, and 214 may be implemented with materials such as InGaN and GaN, for example, and may include an n-type semiconductor layer, a photoactive layer, and a p-type semiconductor layer, and may further include an electrode layer and the like. In addition, the plurality of LED elements 220 may emit any one color in the visible light region, for example, blue or UV.

Meanwhile, when the size of the LED elements 211 , 212 , 213 , and 214 is reduced to a size such as a mini LED element or a micro LED element, local dimming is possible. Image quality can be improved and power efficiency can be increased through local dimming. Here, local dimming is a technology for controlling the brightness of an LED used as a backlight based on a configuration or characteristics of a screen, and is a technology that can dramatically improve a contrast ratio and reduce power consumption. As an example of local dimming, the brightness of the mini LED or micro LED corresponding to a dark screen is adjusted relatively dark to express dark colors, and the brightness of the mini LED or micro LED corresponding to a bright screen is relatively bright to obtain vivid colors. can express

In addition, for example, 15,000 or more mini LED devices may be provided on the circuit board, and for another example, 20,000 or more mini LED devices may be provided on the circuit board.

In addition, the circuit board 210 may be a known circuit board used in a display light source module, and the present invention is not particularly limited thereto.

The heat insulation sheet 230 for a light source according to the present invention is disposed so as to be positioned on the opposite side of the surface on which the above-described plurality of LED elements 220 are mounted on the circuit board 210. At this time, as shown in FIG. 5, as shown in FIG. 5, the heat insulating sheet 230 for the light source is disposed so as to cover the opposite surface corresponding to the position of the plurality of LED elements, or several sheets as shown in FIGS. 9 and 10 It is arranged to cover the surface to realize the light source modules 200' and 200". This is because there is a limit to the area in which the graphite sheet, which is the heat insulating member 110, can be manufactured, and in the case of a large-area display device, one sheet It may be difficult to cover all of the opposite surface with an insulating sheet, and accordingly, it may be designed to cover the opposite surface with several sheets of insulating sheet.

In addition, the present invention includes the adiabatic backlight unit 300 and the liquid crystal display device 1000 having the aforementioned adiabatic light source modules 200, 200', and 200".

Referring to FIGS. 11 and 12, the adiabatic backlight unit 300 includes an adiabatic light source module 200 and several optical sheets 240 disposed on the emission surface of the adiabatic light source module 200. is implemented by In addition, an intermediate molding material 250 supporting and fixing the adiabatic light source module 200 and the optical sheet 240 and a lower case 260 accommodating the adiabatic light source module may be further provided.

The optical sheet 240 is for improving the intensity and direction of light supplied to the liquid crystal display panel 400 through the light source modules 200, 200', and 200", and is limited to known optical sheets used in display backlight units. For example, the optical sheet 240 may include a diffusion sheet 241, a prism sheet 242, and a reflective polarization sheet 243, each of which is an optical sheet commonly used in the art. In addition, the optical sheet 240 may further include sheets performing other functions in addition to the diffusion sheet 241, the prism sheet 242, and the reflective polarizing sheet 243, or at least one of these sheets. In addition, since the optical sheet may include a plurality of sheets of a specific type, and the stacking order of each sheet may vary according to the purpose, the present invention is not particularly limited thereto.

At this time, an air layer may be spaced between the insulating sheet 230 and the lower case 260 positioned on the opposite side of the light exit surface of the insulating backlight unit 300, and through this, the heat generated in the backlight unit A large amount of heat can be minimized from being transferred to the lower case side.

In addition, the liquid crystal display panel 400 may be disposed on the light exit surface of the adiabatic backlight unit 300 described above to implement the liquid crystal display device 1000 . In addition, the liquid crystal display device may further include an upper case 500 supporting a front edge of the liquid crystal display panel 400 .

The liquid crystal display panel 400 includes a color conversion film layer 410, a liquid crystal layer 430, and the liquid crystal layer 430, which convert light emitted from the adiabatic backlight unit 300 into a desired color, at upper and lower portions. It may include a lower substrate 420 and an upper substrate 440 supported by. The color conversion film layer 410 may be used without limitation in the case of a color conversion film layer 410 employed in a known liquid crystal display device, and may be, for example, a fluorescence conversion film or a quantum dot conversion film. In addition, the liquid crystal layer 430 may be a liquid crystal layer employed in a liquid crystal display device, and the present invention is not particularly limited thereto.

On the other hand, although the color conversion film layer 410 has been described as one component of the liquid crystal display panel 400, it is not limited thereto, and the color conversion film layer 410 is an independent component of the liquid crystal display panel 400 and displays a liquid crystal display. Note that it can be provided on the panel.

Also, the lower substrate 420 may include a plurality of pixel electrodes (not shown) and a plurality of thin film transistors (not shown) electrically connected to the pixel electrodes in a one-to-one correspondence. Each thin film transistor switches a driving signal provided to a corresponding pixel electrode. Also, the upper substrate 440 may include a common electrode (not shown) forming an electric field for controlling the alignment of the liquid crystal together with the pixel electrodes.

In addition, in addition to the above-described configurations, configurations employed in known liquid crystal display devices may be further included, and detailed descriptions thereof are omitted in the present invention.

Meanwhile, unlike the liquid crystal display device, which is a light-receiving display device described above, the adiabatic light source module of the present invention may also be implemented as a light-emitting display device. According to an embodiment of the present invention, the LED element included in the adiabatic light source module is an LED element emitting white, UV, or blue light, and further includes a color conversion unit disposed on a path of light emitted from the adiabatic light source module. Thus, a desired color may be displayed.

Alternatively, the plurality of LED elements included in the adiabatic light source module may include LED elements emitting red, green, and blue light.

Although the present invention will be described in more detail through the following examples, the following examples are not intended to limit the scope of the present invention, which should be interpreted to aid understanding of the present invention.

<Example 1>

As a heat spreading member, a heat-resistant acrylic adhesive layer having a thickness of 10 μm and 30 μm was formed on both sides of a 25 μm thick aluminum foil substrate. In addition, as a heat insulating member, an artificial graphite sheet having a thickness of 25 μm (density of 2.1 g/cm ³ , surface direction thermal conductivity of 1400 to 1600 W/m·K, thickness direction thermal conductivity of 15 W/m·K) was prepared. In addition, a black-coated PI film having a thickness of 40 μm having a heat-resistant acrylic adhesive layer having a thickness of 10 μm formed on one surface was prepared as a protective member.

Thereafter, a protective member and a heat spreading member were attached to both surfaces of the heat insulating member, and in the case of the heat spreading member, a thick adhesive layer was placed in contact with the heat insulating member to prepare a heat insulating sheet.

<Example 2>

It was prepared in the same manner as in Example 1, but the thickness of the aluminum foil of the heat spreading member was changed to 50 μm, and the natural graphite sheet (density 1.3 g / cm ³ , surface direction thermal conductivity 250 ~ 350 W/m K, thermal conductivity in the thickness direction of 7 to 10 W/m K) to prepare a heat insulating sheet.

<Example 3>

A heat insulating sheet was manufactured in the same manner as in Example 2, except that a heat accumulating member was disposed on the heat insulating member and a protective member was disposed on the heat accumulating member.

At this time, as the heat accumulation member, a heat-resistant acrylic adhesive layer having a thickness of 10 μm and 30 μm was formed on both sides of a 50 μm-thick aluminum foil substrate, and the thin adhesive layer was attached to the heat insulating member.

<Comparative Example 1>

A heat insulating sheet was manufactured in the same manner as in Example 1, except that the heat spreading member was removed.

<Comparative Example 2>

A heat insulating sheet was manufactured in the same manner as in Example 2, except that the heat spreading member was removed.

<Experimental example>

Insulation sheets according to Examples 1 to 3 and Comparative Examples 1 and 2 were placed on the opposite surface of the mounting surface of a circuit board having a plurality of micro LEDs mounted on one surface as shown in FIG. An insulation sheet was attached on the area where the micro LEDs were mounted in an array of . The width and length of the micro LEDs were 3.5 mm × 2.8 mm, the distance between LEDs was 1 cm, and the width and length of the heat insulating sheet were 8.3 cm × 3 cm.

Thereafter, the circuit board was placed in a thermo-hygrostat, power was applied to the circuit board, and the temperature of the top of the insulation sheet was measured through a thermal imaging camera after 15 minutes. At this time, the measurement points were the center of the specimen (Spot 1) and points near the four corners of the insulation sheet (Spots 2 to 4), and each Example and Comparative Example were measured at the same point.

Afterwards, the degree of diffusion was evaluated by calculating the deviation between the central spot 1 and the spots 2 to 4 near the four corners, respectively, and the results are shown in Table 1 below.

In addition, in order to check the thermal insulation performance of the thermal insulation sheet, the temperature was measured at the same point without the thermal insulation sheet and set as a default value.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 default heat spreading
absence Equipment type/
Thickness (㎛) Al/25 Al/50 Al/50 - - - insulation member Type/Thickness (㎛) Synthetic G/25 Natural G/200 Natural G/200 Synthetic G/25 Natural G/200 - heat accumulation member Metal Substrate Type/Thickness (㎛) - - Al/50 - - - measurement
Temperature
(℃) spot 1 135 133 125 140 136 197 spot 2 123 129 127 127 129 171 spot 3 129 129 129 134 134 172 spot 4 133 133 126 137 137 187 spot 5 127 127 125 132 133 169 Spot 1 temperature reduction rate (%) compared to default -31.47% -32.48 -37.05 -28.93 -30.96 0

In Table 1, natural G and artificial G refer to natural graphite sheets and artificial graphite sheets, respectively.

As can be seen from Table 1, it can be seen that Examples 1 to 3 provided with a heat spreading member have better thermal insulation performance than Comparative Examples 1 to 2.

In addition, in the case of Example 3 equipped with a heat accumulation member, the insulation performance was further improved compared to Example 2, and the temperature deviation between Spot 1 in the center and Spots 2 to 4 near the remaining corners became more uniform, resulting in uniform insulation performance. expression can be seen.

Although one embodiment of the present invention has been described above, the spirit of the present invention is not limited to the embodiments presented herein, and those skilled in the art who understand the spirit of the present invention may add elements within the scope of the same spirit. However, other embodiments can be easily proposed by means of changes, deletions, additions, etc., but these will also fall within the scope of the present invention.

100, 101, 102, 102', 103, 104, 230: insulation sheet
110,231: heat insulating member 120,232: heat spreading member
130,130': protective member 200,200',200": insulation light source module
300: insulation backlight unit 400: liquid crystal display panel
1000: liquid crystal display device

Claims (25)

A plurality of LED elements constituting the light source of the display are provided on the surface opposite to the mounting surface of the circuit board mounted at predetermined intervals to block heat generated from the plurality of LED elements from being transferred in a direction perpendicular to the opposite surface. As a heat insulating sheet for a display light source for
a member attached to a surface opposite to the mounting surface of the circuit board, the heat spreading member including a base material for forming a hotspot having a larger area than the mounting area of each LED device and an adhesive layer disposed on both sides of the base material;
It is disposed on the heat spreading member and includes a first surface perpendicular to the thickness direction and a second surface facing the first surface, and the heat transferred toward the first surface adjacent to the heat spreading member is removed from the first surface. The temperature of the LED element is lowered by moving in the thickness direction of the second side and in the plane direction perpendicular to the thickness direction, but by moving the heat preferentially in the plane direction rather than in the thickness direction, The distance between the LED elements and the heat generation amount of the LED elements are minimized to minimize the overlap due to the surface-direction spreading of the heat transferred from the plurality of LED elements, and to transfer the heat received in the thickness direction as much as possible and accumulate it inside. A heat insulating member that is a graphite sheet having a thickness set in consideration; and
A heat insulating sheet for a display light source comprising a protective member disposed on the second surface of the heat insulating member. According to claim 1,
The heat insulating member is a heat insulating sheet for a display light source comprising at least one graphite sheet of a natural graphite sheet and an artificial graphite sheet. According to claim 1,
The heat insulating member is a heat insulating sheet for a display light source having a thickness of 20 to 500 μm. According to claim 1,
The heat insulating member is a heat insulating sheet for a display light source of natural graphite having a thickness of 90 μm or more. According to claim 1,
The substrate is a heat insulating sheet for a display light source of metal foil or artificial graphite. According to claim 1,
Insulation sheet for a display light source, characterized in that the plane direction thermal conductivity of the substrate is smaller than the plane direction thermal conductivity of the graphite sheet. A plurality of LED elements constituting the light source of the display are provided on the surface opposite to the mounting surface of the circuit board mounted at predetermined intervals to block heat generated from the plurality of LED elements from being transferred in a direction perpendicular to the opposite surface. As a heat insulating sheet for a display light source for
A member attached to a surface opposite to the mounting surface of the circuit board, the heat spreading member including a base material for forming a hotspot having an area larger than the mounting area of each LED element and a first adhesive layer disposed on both sides of the base material;
It is disposed on the heat spreading member and includes a first surface perpendicular to the thickness direction and a second surface facing the first surface, and the heat transferred toward the first surface adjacent to the heat spreading member is removed from the first surface. The temperature of the LED element is lowered by moving in the thickness direction of the second side and in the plane direction perpendicular to the thickness direction, but by moving the heat preferentially in the plane direction rather than in the thickness direction, The distance between the LED elements and the heat generation amount of the LED elements are minimized to minimize the overlap due to the surface-direction spreading of the heat transferred from the plurality of LED elements, and to transfer the heat received in the thickness direction as much as possible and accumulate it inside. A heat insulating member that is a graphite sheet having a thickness set in consideration;
a member attached to the heat insulating member, including a metal substrate for spreading and internally accumulating heat transferred from the heat insulating member, and a second adhesive layer disposed on both sides of the metal substrate; and
A heat insulating sheet for a display light source comprising a protective member attached to one adhesive layer of the heat accumulating member. According to claim 7,
The heat insulating member is a heat insulating sheet for a display light source comprising at least one graphite sheet of a natural graphite sheet and an artificial graphite sheet. According to claim 7,
The heat insulating member is a heat insulating sheet for a display light source having a thickness of 20 to 500 μm. According to claim 7,
The heat insulating member is a heat insulating sheet for a display light source of natural graphite having a thickness of 90 to 300 μm. According to claim 7,
The substrate is a heat insulating sheet for a display light source of metal foil or artificial graphite. According to claim 7,
Heat insulation sheet for a display light source, characterized in that the surface direction thermal conductivity of any one or both of the substrate and the metal substrate is smaller than the surface direction thermal conductivity of the graphite sheet. According to claim 7,
The substrate and the metal substrate each independently include at least one of an aluminum foil and a copper foil, and the graphite sheet is a natural graphite sheet. According to claim 7,
The thickness of the substrate and the metal substrate is each independently 7 ~ 75㎛, the thickness of the first adhesive layer and the second adhesive layer are each independently 7 ~ 55㎛ display light source insulation sheet. According to claim 7,
The length and width of each of the protective member, the heat accumulating member and the heat spreading member are the length and width of the heat insulating member so that the four sides parallel to the thickness direction of the heat insulating member are sealed through the protecting member, the heat accumulating member and the heat spreading member. Insulation sheet for a display light source formed larger than the width. According to claim 1 or 7,
The graphite sheet has thermal conductivity in the plane direction relative to the thermal conductivity in the thickness direction (b) in order to minimize the overlapping of heat received from one LED element and each of the other LED elements disposed adjacent to it in the plane direction, respectively a) A heat insulating sheet for a display light source having a ratio (a/b) of 100 or less. According to claim 1 or 7,
The protective member is a heat insulating sheet for a display light source having a protective film containing at least one selected from the group consisting of polyimide, polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). According to claim 1 or 7,
The protective member is a heat insulating sheet for a display light source having a thickness of 50 ~ 200㎛. circuit board;
A plurality of LED elements mounted on one surface of the circuit board at a predetermined distance from each other; and
A heat insulating light source module comprising a heat insulating sheet for a display light source according to claim 1 or claim 7 disposed on a surface opposite to one surface of the circuit board so that an adhesive member is positioned thereon. According to claim 19,
The plurality of LED elements are a mini LED element or a micro LED element insulated light source module. According to claim 19,
The heat insulating sheet for the display light source is one or more heat insulating light source modules disposed so as to cover the opposite surface corresponding to the position of the plurality of LED elements. An adiabatic light source module according to claim 19; and
A heat insulating backlight unit comprising a plurality of optical sheets disposed on a light exit surface of the light source module. The method of claim 22,
Further comprising a lower case accommodating part or all of the lateral side of the insulated light source module and one side of the insulating sheet in the insulated light source module,
A heat insulating backlight unit spaced apart so that an air layer is formed between the heat insulating sheet and the lower case. an adiabatic backlight unit according to claim 22; and
A liquid crystal display device comprising: a liquid crystal display panel disposed on a light exit surface of the adiabatic backlight unit. A light emitting display device comprising the adiabatic light source module according to claim 19.

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