TWM656529U - Heat dissipation compound and heat dissipation structure using the same - Google Patents

Abstract

A heat dissipation compound is disclosed. The heat dissipation compound includes: a thermal conductive layer; and a thermal insulation adhesive layer formed under the thermal conductive layer and made of an adhesive and tungsten carbide powder solution mixed. The adhesive includes uniformly mixed 55 to 58 parts by weight of acrylate copolymer, 20 to 22 parts by weight of ethyl acetate, and 15 to 20 parts by weight of toluene. The weight ratio when the adhesive is mixed with tungsten carbide powder solution is 1:0.1~1:0.3. The thermal insulation adhesive layer of the present invention replaces the fixing glue in the traditional heat sink and increases thermal insulation effect of traditional heat sinks, so that the thermal insulation adhesive layer with heat dissipation and adhesion functions allows a heat source to reduce heat conduction directly to the shell.

Description

Heat dissipation compound and heat dissipation structure using the heat dissipation compound

The present invention relates to a composite and a structure using the composite, in particular to a heat dissipation composite used in electronic products to provide an effective heat dissipation channel and a heat dissipation structure using the heat dissipation composite.

As electronic products become smaller and smaller, or more and more components are packed into a specific volume, or even the process of basic components such as processors is refined to add more functional structures, waste heat treatment has become a significant problem affecting these electronic products. Since the source of waste heat is the input power converted after the operation of the electronic components, more electronic components mean more waste heat sources and waste heat, not to mention that many electronic components are high energy consumption. Small and closed storage spaces make it easy for accumulated waste heat to be difficult to remove, which causes users to have a bad experience when using these electronic products. To solve this problem, in the design process of many electronic products, heat dissipation structure is the top priority.

Take laptops as an example. This type of product is packed with large basic components such as batteries and keyboard modules in a limited space, leaving little space for other electronic components. As we all know, the most power-consuming devices in laptops are the CPU (Central Processing Unit) and GPU (Graphics Processing Unit). Especially when running at full load, the amount of waste heat generated per unit time is alarming. Although laptops have fans, heat sinks, and vents in the case, which can remove waste heat to the greatest extent possible through internal lower-temperature conductive components and external air circulation, users have the following experience: the high temperature of the CPU or GPU waste heat can be clearly felt in the case near the CPU or GPU. In order to reduce the discomfort caused by this problem, the general laptop heat dissipation module not only uses a copper-aluminum heat dissipation module with a fan to form an air path to transfer the heat of the CPU or GPU to the heat dissipation holes, but also adds a heat sink between the case and the motherboard to increase the heat on the heat sink to be directly transferred to the case and evenly diffused. If a layer of heat insulation is added between the heat conductive sheet and the case, the amount of waste heat transferred to the case can be reduced, but another layer of fixing glue is required to fix it to the case. In this way, the thickness of the entire heat sink structure becomes thicker due to the addition of the heat insulation sheet and fixing glue, which in turn restricts the demand for a thin and light design of the laptop.

In order to reduce the thickness of the above-mentioned heat dissipation module and at the same time reduce the trouble of waste heat being directly transmitted out of the outer casing of the electronic product due to conduction, the present invention is proposed.

This paragraph extracts and compiles certain features of this new invention. Other features will be revealed in subsequent paragraphs. Its purpose is to cover various modifications and similar arrangements within the spirit and scope of the attached patent application.

In order to solve the above-mentioned problems, the present invention discloses a heat dissipation composite. The heat dissipation composite comprises: a heat conductive layer; and a heat insulating adhesive layer formed below the heat conductive layer, which is made by uniformly mixing an adhesive and a tungsten oxide solution. The adhesive comprises 55 to 58 parts by weight of an acrylic copolymer, 20 to 22 parts by weight of ethyl acetate and 15 to 20 parts by weight of toluene uniformly mixed, and the weight ratio of the adhesive to the tungsten oxide solution when mixed is 1:0.1~1:0.3.

Preferably, the material of the thermal conductive layer is graphene, copper foil, aluminum foil or other thermal conductive materials.

Preferably, the thickness of the thermal insulation adhesive layer is between 0.1 mm and 0.15 mm.

According to the present invention, the acrylic copolymer may include butyl acrylate, isooctyl acrylate, vinyl acetate and tackifying resin, wherein the weight ratio of butyl acrylate, isooctyl acrylate, vinyl acetate and tackifying resin is 10:10:5:4. The tackifying resin may be a petroleum resin, a rosin resin, a terpene resin, a terpene phenolic resin or a mixture of at least two of the aforementioned resins.

According to the present invention, the solute in the tungsten oxide solution is tungsten oxide, the solvent is ethyl acetate, butyl acetate or isopropanol, and the weight ratio of the solute to the solvent in the tungsten oxide solution is between 3:7 and 4:6.

The present invention also discloses a heat dissipation structure using a heat dissipation compound, which is installed in a housing having an air inlet opening and an air outlet opening, and is used to carry most of the heat generated by a heat source inside the housing away from the housing by air flowing out of the air outlet opening. The heat dissipation structure comprises: a heat conductive sheet made of the aforementioned heat dissipation compound, the heat conductive sheet having a first end and a second end, and adhered to the inner surface of the housing by the heat insulating adhesive layer, wherein the first end faces the heat source, and the second end is located near the air outlet opening; a fan module, which rotates to inhale external air through the air inlet opening and flows out from the air outlet opening, taking away part of the heat from the heat source and the heat conductive sheet; and a power module, which is electrically connected to the fan module, and is used to provide the power required for the fan module to rotate.

The present invention further discloses another heat dissipation structure using a heat dissipation compound, which is installed in a housing having a heat dissipation position, and is used to guide most of the heat generated by a heat source inside the housing to the heat dissipation position for discharge to the outside of the housing. The heat dissipation structure includes a heat conductive sheet made of the aforementioned heat dissipation compound, the heat conductive sheet having a first end and a second end, and is adhered to the inner surface of the housing by the heat insulating adhesive layer. The first end is closely attached to the heat source, and the second end is located at the heat dissipation position.

This new type of thermal insulation adhesive layer replaces the thermal insulation material and fixing glue in the traditional thermal conductive sheet, so that the thermal insulation adhesive layer with thermal insulation and adhesion functions increases the thermal insulation effect of the traditional thermal conductive sheet and reduces its thickness. The thermal adhesive layer can reduce the heat source from directly transferring heat to the shell during the heat dissipation process. Therefore, the above-mentioned problem can be solved.

1: Heat dissipation compound

2: Laptop computer

3: Thermal imaging device

3’: Temperature tester

4: Smartphone

10: Thermal conductive layer

20: Heat-insulating adhesive layer

30: Acrylic adhesive

40: Main thermal conductive layer

100: Upper casing

110:LED screen module

200: Lower casing

201: Air intake opening

202: Air outlet opening

210: Keyboard module

220: Circuit board

221: Heat source

230:Battery module

240: Fan module

250: Heat sink

251: First end

252: Second end

300: Shell

310: Heat dissipation location

320: Heat source

330: Heat sink

331: First end

332: Second end

Figure 1 is a schematic diagram of the structure of a heat dissipation composite according to the present novel embodiment.

Figure 2 shows the cross-sectional structure of a laptop computer.

Figure 3 shows another structure of the heat sink compound.

Figure 4 shows the cross-sectional structure of a smart phone.

FIG5 shows the test results of the first comparative example and the first to third embodiments.

FIG6 shows the test results of the second comparative example and the fourth to sixth embodiments.

The new invention will be described in more detail by referring to the following implementation methods.

Please see Figure 1, which is a schematic diagram of the structure of a heat dissipation composite 1 according to the implementation method of the novel. The novel heat dissipation composite 1 includes two layered structures: a thermally conductive layer 10 and a thermally insulating adhesive layer 20, and the thermally insulating adhesive layer 20 is formed below the thermally conductive layer 10. It should be noted that the length and thickness of the heat dissipation composite 1 in Figure 1 are not drawn in proportion, and the length will be much larger than the thickness in actual application. The heat dissipation composite 1 can be cut into any shape and installed in the shell of an electronic product, for example, to guide most of the heat generated by the heat source inside the shell to flow in the shell. The thermally conductive layer 10 uses a material commonly used for heat dissipation inside electronic products, such as but not limited to graphene, copper foil or aluminum foil. In the following embodiments, the heat-conducting layer 10 is illustrated using graphene as an example, and its size will be further described in the corresponding embodiments. The function of the heat-conducting layer 10 is to absorb most of the heat emitted by the heat source and conduct it from one end to the other end. However, part of the heat absorbed by the heat-conducting layer 10 will also be conducted to the housing of the electronic product, causing discomfort to the user. Therefore, the heat-insulating adhesive layer 20 has a heat-insulating effect, reducing the heat received from the heat-conducting layer 10.

According to the present invention, the heat-insulating adhesive layer 20 replaces the functions of the existing heat-insulating material and adhesive, thereby reducing the space (thickness) reserved for the installation of the heat-insulating material in the shell of the electronic product. The heat-insulating adhesive layer 20 is made by uniformly mixing an adhesive and a tungsten oxide solution at room temperature. The adhesive includes 55 to 58 parts by weight of an acrylic copolymer, 20 to 22 parts by weight of ethyl acetate, and 15 to 20 parts by weight of toluene, which are uniformly mixed. The weight ratio of the adhesive to the tungsten oxide solution is 1:0.1 to 1:0.3. To further explain, the acrylic copolymer includes butyl acrylate, isooctyl acrylate, vinyl acetate, and a tackifying resin. In terms of mixing ratio, the weight ratio of butyl acrylate, isooctyl acrylate, vinyl acetate and tackifier resin is 10:10:5:4. Butyl acrylate, isooctyl acrylate and vinyl acetate form a solution-type acrylic resin-based sensitive adhesive, and a tackifier resin is added to increase the viscosity. In the following embodiments, the tackifier resin is a petroleum resin. In practice, the tackifier resin can also be a rosin resin, a terpene resin, a terpene phenolic resin or a mixture of at least two of the above resins including a petroleum resin. In the tungsten oxide solution, the solute is tungsten oxide, the solvent can be ethyl acetate, butyl acetate or isopropyl alcohol, and the weight ratio of the solute to the solvent is between 3:7 and 4:6. Since the heat-insulating adhesive layer 20 itself is a heat-resistant adhesive, it can maintain a very thin thickness in application, such as between 0.1mm and 0.15mm.

In order to verify the effectiveness of the heat dissipation compound 1 of the present invention in preventing the waste heat of the heat source from being dissipated through the outer shell, the present invention prepares different heat dissipation compounds 1 in the following three embodiments, applies them to a test shell with a heat source, and conducts actual machine tests with the first comparative example of installing a graphene thermal conductive sheet.

First embodiment

In this embodiment, a graphene thermal conductive layer 10 with a size of 90mm*50mm*0.125mm is prepared. In the preparation of the thermal insulation adhesive layer 20, 20 grams, 20 grams, 10 grams, and 8 grams of butyl acrylate, isooctyl acrylate, vinyl acetate, and petroleum resin are first taken, mixed in a container to prepare about 58 grams of acrylic copolymer. Then, the acrylic copolymer is poured into another container and mixed evenly with a solution made of 22 grams of ethyl acetate and 20 grams of toluene to form about 100 grams of adhesive. Finally, 10 grams of tungsten oxide solution is sprinkled into the container containing the adhesive, and stirred continuously and evenly at room temperature (25-28°C) and normal pressure (1 atmosphere), for example, 15 minutes, to completely mix the tungsten oxide solution and the adhesive. In the first to third embodiments, the solute in the tungsten oxide solution is tungsten oxide, the solvent is ethyl acetate, and the weight ratio of tungsten oxide to ethyl acetate is between 3:7. The mixture is applied to one side of the thermal conductive layer 10, and the thickness is controlled to be between about 0.1mm and 0.15mm to form a first heat dissipation composite.

Second embodiment

In this embodiment, the size of the graphene thermal conductive layer 10 is also 90mm*50mm*0.125mm. In terms of the preparation of the thermal insulation adhesive layer 20, the preparation method and preparation quantity of the adhesive are the same as those in the first embodiment. The difference is that in this embodiment, 20 grams of tungsten oxide solution is poured into a container containing the adhesive, and continuously and evenly stirred at room temperature and pressure to completely mix the tungsten oxide solution and the adhesive. Similarly, the mixture is applied to one side of the thermal conductive layer 10, and the thickness is controlled to be between about 0.1mm and 0.15mm to prepare a second heat dissipation composite.

Third embodiment

In this embodiment, the size of the graphene thermal conductive layer 10 is also 90mm*50mm*0.125mm. In terms of the preparation of the thermal insulation adhesive layer 20, the preparation method and preparation quantity of the adhesive are the same as those in the first embodiment. The difference is that in this embodiment, 30 grams of tungsten oxide solution is poured into a container containing the adhesive, and the tungsten oxide solution and the adhesive are continuously and evenly stirred at room temperature and pressure to completely mix. Similarly, the mixture is applied to one side of the thermal conductive layer 10, and the thickness is controlled to be approximately between 0.1mm and 0.15mm to prepare a third heat dissipation composite.

First comparison example

In this comparative example, in order to make the heat conduction structure objectively consistent, a 90mm*50mm*0.125mm graphene sheet was used, and a layer of backing glue from Changzhou Weiss Shuanglian Company was used to fix the graphene sheet at the same test position as the heat dissipation compound in the above-mentioned embodiment. It should be noted that the thickness of the backing glue is also controlled between 0.1mm and 0.15mm.

The following is an introduction to the test environment of the heat dissipation compound and the graphene glue compound. Please see FIG2 , which shows a cross-sectional structure of a notebook computer 2 , in which the first comparative example and the three embodiments are installed for testing. More specifically, the notebook computer 2 has an upper casing 100 (size: 320mm*220mm*2.4mm) and a lower casing 200 (size: 320mm*220mm*17.1mm), and the material is a thermoplastic plastic formed by combining PC (Polycarbonate) + ABS (Acrylonitrile Butadiene Styrene); the upper casing includes an LCD (Liquid-Crystal Display) screen module 110, and the lower casing 200 includes other important electronic or mechanical modules, such as a keyboard module 210, a circuit board 220, a battery module 230, a fan module 240 and a heat sink 250. There are many active and passive components on the circuit board 220, including the components that generate the most heat, referred to as heat sources 221. The main heat sources 221 are CPU and GPU (Graphics Processing Unit). The first comparative example and the three embodiments are applied to compare the heat dissipation effect of the CPU, and the heat source 221 is the CPU. The CPU used is AMD's model Ryzen 7040 Phoenix, with a thermal design power consumption of 30W. The Ryzen 7040 Phoenix CPU is integrated with a GPU, and the memory is shared with the GPU and integrated on the same chip. Therefore, using different software to perform a burn-in test can drive the CPU part or the GPU part to run at maximum power, and at the same time, the rate of waste heat generated is also the highest. The Ryzen 7040 Phoenix CPU contains 6G of VRAM (Video RAM, i.e. video random access memory) inside. Other active components that generate heat on the circuit board 220, such as narrow voltage DC IC, audio source IC codec IC, etc., consume less power than the Ryzen 7040 Phoenix CPU, and have the same impact on the first comparative example and the three embodiments. The battery module 230 is powered by a 5700WH DC lithium battery when no external power is used. The fan module 240 is a fan of Lenovo model X200, and the heat conducting sheet 250 is a graphene sheet, a first heat dissipation compound, a second heat dissipation compound, and a third heat dissipation compound.

During the test, the heat of the heat source 221 is dissipated to the surrounding environment. Since the fan module 240 is activated to bring in the external low-temperature air, the heat flow (indicated by several arrows) is mainly downward and to the side. It should be noted that the lower housing 200 includes an air inlet opening 201 and an air outlet opening 202. The heat conductive sheet 250 has a first end 251 and a second end 252. The first end 251 faces the heat source 221, and the second end 252 is located near the air outlet opening 202. When the fan module 240 rotates, it draws in external air through the air inlet opening 201 and flows out through the air outlet opening 202 (the airflow direction is indicated by the arrow, the darker the background, the higher the temperature), taking away some of the heat from the heat source 221 and the heat conducting sheet 250, while a small amount of heat will be directly dissipated from the lower housing 200 into the air through conduction.

A FOTRIC model T530 thermal imager 3 is placed under the laptop 2 to detect temperature changes under the lower case 200. The asterisk in Figure 2 is the highest temperature point detected by the thermal imager 3 under the laptop 2, which is just below the center of the heat source 221. During the test, a YOKOGAWA model MX100 temperature tester 3' was used to sample and measure the temperature of the highest temperature point, with a sampling rate of once per second. The Ryzen 7040 Phoenix CPU ran the stability test software prime95. The total test time was 7200 seconds, which means that 7200 temperature records were obtained.

The test results of the first comparative example and the three embodiments are shown in FIG5 . As can be seen from FIG5 , in the first comparative example, the temperature of the temperature detection point rises rapidly from the starting temperature in the first 700 seconds, and then rises slowly. After exceeding 50°C, there is no sign of stopping. In the first embodiment, the temperature of the temperature detection point stagnates when it rises to about 50°C. Although the temperature of the temperature detection point is higher than the temperature in the first comparative example at the same time between 700 seconds and 3700 seconds, the temperature of the temperature detection point of the first embodiment has been lower than the detection data of the first comparative example after 3700 seconds. The second heat dissipation compound of the second embodiment has the best heat dissipation effect, and the entire temperature curve is below all curves, that is, the temperature felt by the user under the heat source 221 of the notebook computer 2 using the second heat dissipation compound as the heat conductive sheet 250 is lower than that of other notebook computers 2 using heat dissipation compounds or graphene sheets. Although the heat dissipation effect of the third heat dissipation compound of the third embodiment is better than that of the graphene sheet, the effect is between the first heat dissipation compound and the second heat dissipation compound. It can be seen from this that adding more than 30% of the weight of tungsten oxide solution to the adhesive will not only increase the manufacturing cost, but also the heat insulation effect will not increase.

The first comparative example and the three examples mentioned above were conducted using an adhesive made of acrylic copolymer, ethyl acetate and toluene at a weight ratio of 58:22:20. Next, a second comparative example, a fourth example, a fifth example and a sixth example are used to illustrate the effect of adhesives at different component ratios on the test results.

Fourth embodiment

In this embodiment, a graphene thermal conductive layer 10 with a size of 90mm*50mm*0.125mm is prepared. In terms of the preparation of the thermal insulation adhesive layer 20, butyl acrylate, isooctyl acrylate, vinyl acetate and petroleum resin are first mixed in a container according to a weight ratio of 10:10:5:4 to prepare about 55 grams of acrylic copolymer. Then the acrylic copolymer is poured into another container and mixed evenly with a solution made of 20 grams of ethyl acetate and 15 grams of toluene to form about 90 grams of adhesive. Finally, 9 grams of tungsten oxide solution is poured into the container containing the adhesive and stirred evenly at room temperature (25-28°C) and normal pressure (1 atmosphere) for, for example, 15 minutes to completely mix the tungsten oxide solution and the adhesive. In the fourth to sixth embodiments, the solute in the tungsten oxide solution is tungsten oxide, the solvent is ethyl acetate, and the weight ratio of tungsten oxide to ethyl acetate is between 4:6. The mixture is applied to one side of the thermal conductive layer 10, and the thickness is controlled to be between about 0.1mm and 0.15mm to produce a fourth heat dissipation composite.

Fifth embodiment

In this embodiment, the size of the graphene thermal conductive layer 10 is also 90mm*50mm*0.125mm. In terms of the preparation of the thermal insulation adhesive layer 20, the preparation method and preparation quantity of the adhesive are the same as those of the fourth embodiment. The difference is that in this embodiment, 18 grams of tungsten oxide solution is poured into a container containing the adhesive, and the tungsten oxide solution and the adhesive are continuously and evenly stirred at room temperature and pressure to completely mix. Similarly, the mixture is applied to one side of the thermal conductive layer 10, and the thickness is controlled to be approximately between 0.1mm and 0.15mm to prepare a fifth heat dissipation composite.

Sixth embodiment

In this embodiment, the size of the graphene thermal conductive layer 10 is also 90mm*50mm*0.125mm. In terms of the preparation of the thermal insulation adhesive layer 20, the preparation method and preparation quantity of the adhesive are the same as those of the fourth embodiment. The difference is that in this embodiment, 27 grams of tungsten oxide solution is poured into a container containing the adhesive, and the tungsten oxide solution and the adhesive are continuously and evenly stirred at room temperature and pressure to completely mix. Similarly, the mixture is applied to one side of the thermal conductive layer 10, and the thickness is controlled to be between about 0.1mm and 0.15mm to prepare a sixth heat dissipation composite.

Second comparison example

In this comparative example, in order to make the heat conduction structure objectively consistent, a graphene sheet of the same specifications as in the first comparative example was used, with a layer of Changzhou Weiss double-linked backing adhesive underneath to fix the graphene sheet at the same test position as the heat dissipation compound in the aforementioned embodiment. The thickness of the backing adhesive is controlled between 0.1mm and 0.15mm.

In terms of the test environment, the second comparative example and the fourth to sixth embodiments used the aforementioned laptop 2, and the layout was as described in Figure 2 and the related text. During the test, a temperature tester 3' of YOKOGAWA model MX100 was used to sample and measure the temperature at the highest temperature point, with a sampling rate of once per second. The Ryzen 7040 Phoenix CPU ran the stability test software FurMark+TCT (test software used by the AMD platform) to test the GPU performance in the Ryzen 7040 Phoenix CPU. The total test time was 7200 seconds, so 7200 temperature records were obtained.

The test results of the second comparative example and the fourth to sixth embodiments are shown in FIG6 . As can be seen from FIG6 , in the second comparative example, the temperature of the temperature detection point rises rapidly from the starting temperature in the first 500 seconds, and then rises slowly. After exceeding 58°C, there is no sign of stopping. In the fourth embodiment, the temperature of the temperature detection point stagnates when it rises to about 50°C. Although the temperature of the temperature detection point is higher than the temperature in the second comparative example at the same time between 300 seconds and 3000 seconds, the temperature of the temperature detection point of the fourth embodiment is always lower than the detection data of the second comparative example after 3000 seconds, and the highest temperature is about 54°C. The fifth heat dissipation composite of the fifth embodiment has the best heat dissipation effect, and the entire temperature curve is below all curves. Although the heat dissipation effect of the sixth heat dissipation compound of the sixth embodiment is better than that of the graphene sheet, the effect is between the fourth heat dissipation compound and the fifth heat dissipation compound. It can be seen that adding more than 30% of the weight of tungsten oxide solution to this adhesive will increase the manufacturing cost but not the heat dissipation effect.

According to the present invention, the heat dissipation compound 1 can also have other structures. See Figure 3, which shows another structure of the heat dissipation compound 1. The heat dissipation compound 1 is further coated with a layer of acrylic backing 30 on the side of the heat conductive layer 10 that is different from the heat insulating adhesive layer 20, and is bonded to a main heat conductive layer 40. The material of the main heat conductive layer 40 can also be one of graphene, copper foil or aluminum foil or other heat dissipation materials, and the shape can be the same as or different from that of the heat conductive layer 10. If the shapes of the two are the same, the heat conduction performance of the heat dissipation compound 1 can be increased. If the shapes of the main heat conductive layer 40 and the heat conductive layer 10 are different, the heat conduction performance can be locally enhanced, or the waste heat can be directed to different air outlet openings.

The notebook computer 2 used to test the performance of the heat dissipation compound of the above-mentioned embodiment is a best example of the application of the present invention, in which a heat dissipation structure using the heat dissipation compound is formed. Generally speaking, the heat dissipation structure using the heat dissipation compound is installed in a housing (lower housing 200) having an air inlet opening 201 and an air outlet opening 202 as shown in FIG. 2, so as to carry most of the heat generated by a heat source 221 inside the housing away from the housing by air flowing out of the air outlet opening 202. The heat dissipation structure using the heat dissipation compound includes a heat conductive sheet 250 made of the above-mentioned heat dissipation compound 1, a fan module 240 and a power module. The heat conductive sheet 250 has a first end 251 and a second end 252, and is adhered to the inner surface of the housing by a heat insulating adhesive layer 20. The first end 251 faces the heat source 221, and the second end 252 is located near the air outlet opening 202. The fan module 240 rotates to inhale the external air through the air inlet opening 201 and out of the air outlet opening 202, taking away part of the heat from the heat source 221 and the heat conductive sheet 250. The power module can be the battery module 230 in FIG. 2, or it can be a transformer in a notebook computer 2 or other electronic products, which can convert the AC power of the mains into working DC power. The power module is electrically connected to the fan module 240 to provide the power required for the fan module 240 to rotate.

In the aforementioned application examples, the heat conducting sheet can be used in conjunction with the fan module to conduct and dissipate heat. In practice, the heat conducting sheet made of the novel heat dissipating compound 1 can also be used in electronic devices without fan modules and internal air flow. It can simply rely on conduction to guide the heat generated by the heat source to the appropriate position of the casing, and then discharge it to the external space and reduce the surface temperature of the casing. The best application example is a smart phone or tablet.

Please see FIG. 4, which shows a cross-sectional structure of a smart phone 4. A heat dissipation structure using a heat dissipation compound can be installed in a housing 300 of a smart phone 4 having a heat dissipation position 310, so as to guide most of the heat generated by a heat source 320 (such as a processor) inside the housing 300 to the heat dissipation position 310 for discharge to the outside of the housing 300. In practice, the heat dissipation position 310 can be a speaker hole on the side of the housing 300 of the smart phone 4, and the air flowing near the heat dissipation position 310 takes away the conducted heat. The heat dissipation structure using the heat dissipation compound is mainly a heat conductive sheet 330 made of the aforementioned heat dissipation compound. The heat conductive sheet 330 has a first end 331 and a second end 332, and is adhered to the inner surface of the housing 300 by a heat insulating adhesive layer. During installation, the first end 331 is close to the heat source 320, and the second end 332 is located near the heat dissipation position 310.

Although the present invention has been disclosed in the form of implementation as above, it is not intended to limit the present invention. Anyone with common knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope of the patent application attached hereto.

1: Heat dissipation compound

10: Thermal conductive layer

20: Heat-insulating adhesive layer

Claims (10)

A heat dissipation composite comprises: a heat conductive layer; and a heat insulating adhesive layer formed below the heat conductive layer, which is made by uniformly mixing an adhesive and a tungsten oxide solution, wherein the adhesive comprises 55 to 58 parts by weight of an acrylic copolymer, 20 to 22 parts by weight of ethyl acetate and 15 to 20 parts by weight of toluene uniformly mixed, and the weight ratio of the adhesive to the tungsten oxide solution when mixed is 1:0.1~1:0.3. The heat dissipation composite as described in claim 1, wherein the material of the heat conductive layer is graphene, copper foil or aluminum foil. The heat dissipation composite as described in claim 1, wherein the thickness of the thermal insulation adhesive layer is between 0.1 mm and 0.15 mm. The heat dissipation composite as described in claim 1, wherein the acrylic copolymer comprises butyl acrylate, isooctyl acrylate, vinyl acetate and a tackifying resin. The heat dissipation composite as described in claim 4, wherein the weight ratio of butyl acrylate, isooctyl acrylate, vinyl acetate and tackifying resin is 10:10:5:4. The heat dissipation composite as described in claim 4, wherein the tackifying resin is a petroleum resin, a rosin resin, a terpene resin, a terpene phenolic resin or a mixture of at least two of the aforementioned resins. The heat dissipation composite as described in claim 1, wherein the solute in the tungsten oxide solution is tungsten oxide, and the solvent is ethyl acetate, butyl acetate or isopropyl alcohol. The heat dissipation composite as described in claim 1, wherein the weight ratio of the solute to the solvent in the tungsten oxide solution is between 3:7 and 4:6. A heat dissipation structure using a heat dissipation compound is installed in a shell having an air inlet opening and an air outlet opening, and is used to carry most of the heat generated by a heat source inside the shell away from the shell by air flowing out of the air outlet opening, comprising: a heat conductive sheet made of the heat dissipation compound of any one of claims 1 to 8, the heat conductive sheet having a first end and a second end, and adhered to the inner surface of the shell by the heat insulating adhesive layer, wherein the first The first end faces the heat source, and the second end is located near the air outlet opening; a fan module is arranged inside the housing near the air inlet opening, and rotates to inhale external air through the air inlet opening and flow out from the air outlet opening, taking away part of the heat from the heat source and the heat conductive sheet; and a power module is arranged inside the housing near the air outlet opening, and is electrically connected to the fan module to provide the power required for the fan module to rotate. A heat dissipation structure using a heat dissipation compound is installed in a housing having a heat dissipation position, and is used to guide most of the heat generated by a heat source inside the housing to the heat dissipation position for discharge to the outside of the housing. It is characterized in that it comprises a heat conductive sheet made of the heat dissipation compound of any one of claims 1 to 8, the heat conductive sheet has a first end and a second end, and is adhered to the inner surface of the housing by the heat insulating adhesive layer, wherein the first end is closely attached to the heat source, and the second end is located near the heat dissipation position.

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