Heat dissipation and soundproofing sheet and its manufacturing method

Abstract

The heat dissipation soundproof sheet 1 includes a soundproof sheet layer 2a-2e and a thermally conductive sheet layer 3a-3e, and the thermally conductive sheet layer 3a-3e is a sheet layer containing a matrix resin and a thermally conductive filler, and the soundproof sheet layer 2a-2e and the thermally conductive sheet layer 3a-3e are laminated in a thickness direction of the heat dissipation soundproof sheet 1. In this manufacturing method, a thermally conductive composition and a soundproof sheet are placed on a substrate sheet, and a substrate sheet is placed on the thermally conductive composition and rolled to form a laminated single sheet of the soundproof sheet layer and the thermally conductive sheet layer, and a plurality of the single laminate sheets are laminated to form a multi-layer laminate sheet, and the multi-layer laminate sheet is cut in the thickness direction to obtain a heat dissipation soundproof sheet. This provides a heat dissipation soundproof sheet with a good balance between thermal conductivity and soundproofing, and a manufacturing method thereof.

Description

[Technical field]

[0001] The present invention relates to a heat-dissipating and soundproofing sheet having thermal conductivity and soundproofing properties, and a method for producing the same. [Background technology]

[0002] The driving noise of compressors used in air conditioners for electric vehicles is unpleasant, so soundproofing is performed using soundproofing materials. Glass wool is a well-known soundproofing material. Patent Document 1 proposes a soundproof sheet including a nonwoven fabric layer including an ultrafine fiber layer and a thick fiber layer, and a glass wool layer. Patent Document 2 proposes a soundproof panel including a flame-retardant tarpaulin sheet and a glass wool molded sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-135554 A [Patent Document 2] JP 2021-067087 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the sound absorption coefficient of the soundproof sheets of the above-mentioned conventional techniques is still insufficient, and the thermal conductivity has not been improved, so that further improvement is required.

[0005] In order to solve the above-mentioned problems in the conventional art, the present invention provides a heat dissipating and soundproofing sheet having a good balance between thermal conductivity and soundproofing properties, and a method for producing the same. [Means for solving the problem]

[0006] One embodiment of the present invention is a heat dissipating soundproof sheet including a soundproof sheet layer and a thermally conductive sheet layer, the thermally conductive sheet layer being a sheet layer including a matrix resin and a thermally conductive filler, the soundproof sheet layer and the thermally conductive sheet layer being: A plurality of layers are laminated in the thickness direction of the heat dissipation and soundproof sheet, and the thickness direction is a direction perpendicular to the lamination direction of the heat dissipation and soundproof sheet and the thermal conductive sheet layer. This relates to heat dissipation and soundproofing sheets.

[0007] Another embodiment of the present invention is a method for producing the heat dissipating and soundproofing sheet, comprising the steps of: placing a thermally conductive composition and a soundproofing sheet on a base sheet; placing another base sheet on the thermally conductive composition and rolling the thermally conductive composition to form a laminated single sheet of a soundproofing sheet layer and a thermally conductive sheet layer; Laminated Single Sheet The present invention relates to a method for producing a heat-dissipating and sound-proof sheet, which comprises laminating a plurality of sheets of the above-mentioned to obtain a multi-layer laminated sheet, and cutting the multi-layer laminated sheet in the thickness direction to obtain a heat-dissipating and sound-proof sheet. Effect of the Invention

[0008] The heat-dissipating, soundproofing sheet of the present invention comprises a soundproofing sheet layer and a thermally conductive sheet layer, the thermally conductive sheet layer being a sheet layer of a composition containing a matrix resin and a thermally conductive filler, and the soundproofing sheet layer and the thermally conductive sheet layer are laminated in multiple layers facing in the thickness direction of the heat-dissipating, soundproofing sheet, thereby providing a heat-dissipating, soundproofing sheet with a good balance between thermal conductivity and soundproofing properties, and a method for producing the same. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1A is a schematic perspective view of a heat-dissipating, soundproof sheet according to one embodiment of the present invention, and FIG. 1B is a schematic cross-sectional view taken along line II in FIG. 1A. [Figure 2A] FIG. 2A is a schematic cross-sectional process diagram of a heat-dissipating, sound-proof sheet according to one embodiment of the present invention, showing a process in which a thermally conductive sheet is placed on a base sheet. [Figure 2B] FIG. 2B is a schematic cross-sectional process diagram of the same, showing a process in which a thermally conductive sheet, a soundproof sheet, and a base sheet are placed on a base sheet. [Figure 2C] FIG. 2C is a schematic cross-sectional process diagram of the same, showing the state in which the soundproof sheet is pressed into the thermally conductive sheet by rolling from the state shown in FIG. 2B. [Figure 2D] FIG. 2D is a schematic cross-sectional process diagram of the same, showing a state after the upper base sheet has been peeled off from the state shown in FIG. 2C. [Figure 2E] FIG. 2E is a schematic cross-sectional process diagram of the same, showing a state in which a laminated single sheet of a soundproof sheet and a thermally conductive sheet is laminated from the state of FIG. 2D. [Figure 2F] FIG. 2F is a schematic cross-sectional process diagram of the same, showing a state in which an end portion has been cut from the state of FIG. 2E. [Figure 2G] FIG. 2G is a schematic cross-sectional process diagram of the same, showing a process for cutting the multi-layer laminated sheet in the thickness direction from the state of FIG. 2F to obtain a heat dissipating soundproof sheet. [Diagram 3] 3A-B are schematic explanatory views showing a method for measuring the thermal conductivity of a sample in one embodiment of the present invention. [Figure 4] FIG. 4 is a graph showing the normal incidence sound absorption coefficient of an embodiment of the present invention and a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention is a heat dissipating soundproof sheet including a soundproof sheet layer and a thermally conductive sheet layer. The thermally conductive sheet layer is a sheet layer of a composition including a matrix resin and a thermally conductive filler, and the matrix resin is preferably a thermosetting resin. If it is a thermosetting resin, it has little dimensional change even when heated and is highly durable. The thermally conductive filler is preferable because of its high thermal conductivity.

[0011] The soundproof sheet layer and the thermally conductive sheet layer are laminated in a plurality of layers in the thickness direction (cross-sectional direction) of the heat dissipating soundproof sheet. This allows soundproofing to be at a practical level and allows the thermal conductivity in the thickness direction to be high. Thermal conductivity and soundproofing are inversely proportional to each other, and the soundproofing decreases when the thermal conductivity is increased, and vice versa. However, the present invention can provide a heat dissipating soundproof sheet with a good balance between thermal conductivity and soundproofing. The multiple layers may be any number of layers as long as each layer is 2 or more, for example, 2 to 1000 layers.

[0012] The soundproof sheet layer and the thermally conductive sheet layer are preferably laminated in parallel (stripes), which makes it easy to manufacture, provides a practical level of soundproofing, and increases thermal conductivity in the thickness direction.

[0013] The soundproof sheet layer is preferably a glass wool sheet layer, a rock wool sheet layer, a ceramic fiber sheet layer, a synthetic fiber nonwoven fabric sheet layer, or a foamed resin sheet layer. These sheets have high soundproofing properties. The synthetic fibers are preferably polyesters such as polyethylene terephthalate, polyolefins such as polypropylene, and polyamides such as nylon 6, and are preferably in the form of nonwoven fabric, woven fabric, knitted fabric, mat, etc. The foamed resin sheet layer is preferably silicone, polyurethane, or other resins, and the foaming ratio is preferably 1.1 to 5 times.

[0014] The thickness of each soundproof sheet layer is preferably 0.5 to 10 mm, more preferably 1 to 9 mm, and even more preferably 2 to 8 mm, which provides suitable soundproofing properties.

[0015] The matrix resin is preferably a cured silicone resin. The silicone resin is preferably a silicone rubber or a silicone gel. Silicone resin is heat resistant and is safe for shielding noise sources such as compressors, motors, and other heat-generating equipment. Among them, addition reaction curing type silicone rubber is preferable because it can be cured at a relatively low temperature and is uniformly cured to the inside. For example, it can be heat cured at 100 to 120°C for 10 to 15 minutes.

[0016] The thickness of the thermally conductive sheet layer is preferably 0.5 to 5 mm, more preferably 0.7 to 4.5 mm, and further preferably 1 to 4 mm. This thickness can increase the thermal conductivity and improve the heat dissipation characteristics.

[0017] When the thickness of one soundproof sheet layer is S and the thickness of the thermally conductive sheet layer is T, it is preferable that S ≧ T. When the thicknesses of both layers satisfy the above relationship, a good balance between heat dissipation characteristics (thermal conductivity) and soundproofing properties is achieved.

[0018] The thermal conductivity of the thermally conductive sheet layer in accordance with ISO 22007-2:2008, hot disk method is preferably 0.5 to 20 W / m K, more preferably 0.5 to 18 W / m K, and even more preferably 0.6 to 15 W / m K. This can improve the heat dissipation characteristics.

[0019] The tack value of the thermally conductive sheet layer is preferably 0.3 N or more, more preferably 0.3 to 20 N, and even more preferably 0.4 to 18 N. This allows for increased adhesion to the heat-generating device that is the source of noise, and improves the heat dissipation characteristics. Furthermore, the adhesive strength with the soundproof sheet layer can be increased, allowing for lamination and integration without the use of adhesive. The tack value is a numerical value of stickiness, and can be measured using a tackiness tester or tackiness checker.

[0020] The heat dissipating and soundproofing sheet preferably has a thickness of 1 to 50 mm, more preferably 2 to 45 mm, and further preferably 3 to 40 mm. This thickness is effective in blocking noise sources.

[0021] The interface between the soundproof sheet layer and the thermally conductive sheet layer may be bonded with a primer. Bonding with a primer can strengthen the integrity of the soundproof sheet layer and the thermally conductive sheet layer. Examples of primers that can be used include epoxy resins, silane coupling agents, and hot melt adhesive sheets. Silane coupling agents include R(CH3) a Si(OR') 4-a (R is an unsubstituted or substituted organic group having 1 to 20 carbon atoms, R' is an alkyl group having 1 to 4 carbon atoms, and a is 0 or 1) or a partial hydrolyzate thereof. R(CH3) a Si(OR') 4-aExamples of alkoxysilane compounds (hereinafter simply referred to as "silane") represented by the formula (R is an unsubstituted or substituted organic group having 1 to 20 carbon atoms, R' is an alkyl group having 1 to 4 carbon atoms, and a is 0 or 1) include methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, pentyltrimethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, and octadecyltriethoxysilane. The above silane compounds can be used alone or in combination of two or more.

[0022] The method for producing the heat-dissipating and soundproof sheet of the present invention preferably includes the following steps. (1) Manufacturing process of laminated single sheet The thermally conductive composition and the soundproof sheet are placed on a substrate sheet, and the substrate sheet is placed on the thermally conductive composition and rolled to form a laminated single sheet of the soundproof sheet layer and the thermally conductive sheet layer. At this time, the soundproof sheet layer and the thermally conductive sheet layer may be pressurized and heated to cure the thermally conductive sheet layer, or the interface between the two layers may be bonded with a primer. (2) Manufacturing process for multi-layered sheets A plurality of the single-layer laminate sheets are laminated to form a multi-layer laminate sheet. At this time, the thermally conductive sheet layer may be further cured by heating, or the interfaces between the single-layer laminate sheets may be bonded with a primer. (3) Cutting process The multi-layer laminate sheet is cut in the thickness direction to obtain a heat dissipating and soundproof sheet.

[0023] The thermally conductive sheet layer is preferably prepared by adding 100 to 3500 parts by mass of a thermally conductive filler to 100 parts by mass of a matrix resin and mixing them to form a compound composition. The thermally conductive filler is preferably inorganic particles such as aluminum oxide (alumina), zinc oxide, magnesium oxide, aluminum nitride, boron nitride, aluminum hydroxide, or silicon carbide.

[0024] A part or all of the inorganic particles are RaSi(OR') 4-a (wherein R is an unsubstituted or substituted organic group having 6 to 12 carbon atoms, R' is an alkyl group having 1 to 4 carbon atoms, and a is 0 or 1), and preferably R is an alkyl group having 8 to 12 carbon atoms. This increases the affinity of the inorganic particles with the matrix resin, making them easier to mix with. Specific compounds are as described above.

[0025] The matrix resin of the present invention may contain other components as necessary. For example, heat resistance improvers such as red iron oxide, titanium oxide, and cerium oxide, flame retardants, and flame retardant assistants may be added. Organic or inorganic particle pigments may be added for the purpose of coloring and color matching. Alkoxy group-containing silicone may be added as a material added for the purpose of filler surface treatment, etc.

[0026] The heat dissipating soundproof sheet of the present invention is used by, for example, arranging the heat dissipating soundproof sheet around a compressor, which is a noise source, so that the lamination direction of the soundproof sheet layer and the thermally conductive sheet layer faces the noise source. The means for arranging the heat dissipating soundproof sheet around the compressor is preferably a means for directly wrapping the heat dissipating soundproof sheet around the compressor, or a means for forming the heat dissipating soundproof sheet into a box shape and placing the compressor inside. As an example, the heat dissipating soundproof sheet is directly wrapped around a compressor such as an air conditioner for an electric vehicle, or the heat dissipating soundproof sheet is formed into a box shape and the compressor is placed inside. Since the heat generated by the compressor is transferred to the outside through the thermally conductive sheet layer, the heat is cooled by introducing outside air from outside the vehicle and / or by blowing the wind from a fan. Aluminum foil or stainless steel foil with high cooling properties may be in contact with the compressor.

[0027] The following description will be given with reference to the drawings. In the following drawings, the same reference numerals indicate the same objects. Fig. 1A is a schematic perspective view of a heat dissipating and soundproof sheet 1 according to one embodiment of the present invention, and Fig. 1B is a schematic cross-sectional view taken along line II in Fig. 1A. This heat dissipating and soundproof sheet 1 is formed by laminating soundproof sheets 2a-2e and thermally conductive sheets 3a-3e together.

[0028] 2A-G are schematic cross-sectional process diagrams of a heat dissipating soundproof sheet according to an embodiment of the present invention. FIG. 2A is a process diagram in which a heat conductive sheet 3a is placed on a base sheet (polyester film) 4. FIG. 2B is a schematic cross-sectional process diagram in which a heat conductive sheet 3a, a soundproof sheet 2a, and a base sheet 5 are placed on a base sheet 4. FIG. 2C is a schematic cross-sectional process diagram in which the soundproof sheet 2a is pressed into the heat conductive sheet 3a by rolling from the state of FIG. 2B. FIG. 2D is a schematic cross-sectional process diagram in which the upper base sheet is peeled off from the state of FIG. 2C. FIG. 2E is a schematic cross-sectional process diagram in which the soundproof sheets 2a-2c and the heat conductive sheets 3a-3c are laminated and integrated from the state of FIG. 2D. In this process, it is preferable to heat and harden the heat conductive sheet 3a. FIG. 2F is a schematic cross-sectional process diagram in which the end is cut with a cutter 6 from the state of FIG. 2E. FIG. 2G is a schematic cross-sectional process diagram of the same, showing a process for cutting the multi-layer laminate sheet from the state of FIG. 2F in the thickness direction with a cutter 6 to form the heat-dissipating soundproof sheet 1. EXAMPLES

[0029] The present invention will be described below with reference to examples, but is not limited to these examples. Various parameters were measured by the following methods.

[0030] <Thermal conductivity> The thermal conductivity was measured using a hot disk (compliant with ISO 22007-2:2008). As shown in FIG. 3A, this thermal conductivity measuring device 11 sandwiches a polyimide film sensor 12 between two samples 13a and 13b, applies a constant power to the sensor 12, and analyzes the thermal characteristics from the temperature rise of the sensor 12 by generating a constant amount of heat. The sensor 12 has a tip 14 with a diameter of 7 mm, and as shown in FIG. 3B, has a double spiral electrode structure, with an applied current electrode 15 and a resistance value electrode (temperature measurement electrode) 16 arranged at the bottom. The measurement sample can be obtained by rolling and molding the degassed thermally conductive liquid composition to a thickness of 7 mm or more. The thermal conductivity is calculated using the following formula (Mathematical formula 1).

number

[0031] Example 1 1. Preparation of thermally conductive silicone rubber sheet (1) Silicone component A commercially available two-part room temperature curing silicone rubber (addition reaction curing silicone rubber) was used as the silicone component. The two-part room temperature curing silicone rubber has a base polymer component and a platinum metal catalyst added in advance as part A, and a base polymer component and a crosslinking component added in advance as part B. Part A and part B were used in a 50:50 ratio. (2) Thermally conductive particles (a) Small thermally conductive particles The small diameter thermally conductive particles used were alumina with an average particle size of 1 μm that had been surface-treated with a silane coupling agent. The amount added was 50 parts by weight per 100 parts by weight of the silicone component. The average particle size was measured using the laser diffraction light scattering method, with the 50% by mass particle size being the same below. The measuring device used was the LA-950S2 laser diffraction / scattering type particle distribution measuring device manufactured by Horiba, Ltd. (b) Medium-sized thermally conductive particles The medium-sized thermally conductive particles were made of alumina with an average particle size of 3 μm, which had been surface-treated with a silane coupling agent. The amount of the additive was 200 parts by weight per 100 parts by weight of the silicone component. (c) Large-sized thermally conductive particles Two types of large-diameter thermally conductive particles were used, but neither was surface-treated with a silane coupling agent and was used as is. (i) Alumina with an average particle size of 50 μm was used. The amount added was 200 parts by weight per 100 parts by weight of the silicone component. (d) Amount of thermally conductive particles added To 100 parts by weight of the silicone component, 50 parts by weight of small-diameter thermally conductive particles, 200 parts by weight of medium-diameter thermally conductive particles, and 200 parts by weight of large-diameter thermally conductive particles were added, for a total of 450 parts by weight. (3) Seat characteristics The compound was placed on a release-treated polyester film, and another release-treated polyester film was placed on top. The gap between the rolls was adjusted to obtain a thickness of 5 mm using a constant speed roll, and the compound sandwiched between the polyester films was passed through a sheet of a constant thickness. It was then cured at 120°C for 10 minutes to form a silicone rubber sheet 500 mm long, 500 mm wide, and 5.0 mm thick. The thermal conductivity of the resulting heat dissipation sheet was 1.5 W / m K, and the hardness was 15 Shore OO. When the cut surface of this thermally conductive silicone sheet was measured with a tackiness checker, the tackiness was found to be 0.8N. 2. Soundproofing sheet As a soundproofing sheet, use glass wool (mass 1600g / m) made by Central Glass Fiber Co., Ltd. 2 , thickness 5 mm) was used. 3. Creating a heat dissipating and soundproof sheet A heat dissipating soundproof sheet was prepared by the method shown in Figures 2A to 2G. The thickness of each soundproof sheet layer in this heat dissipating soundproof sheet was 5 mm, and the thickness of each thermally conductive sheet layer was 5 mm. 50 layers of each of the single layer laminated sheets were laminated in parallel (striped) and cured for 10 minutes at 120°C without pressure, with a length of 500 mm, a width of 500 mm, a plate thickness (thickness in the direction of noise generation) of 5 mm, and a mass of 4300 g / m 2 The heat dissipating and soundproofing sheet of the thermally conductive silicone sheet was found to have a tack value of 0.8 N, the same as above.

[0032] Comparative Example 1 As Comparative Example 1, the glass wool sheet of Example 1 (mass 1600 g / m 2 , thickness 5 mm) was used.

[0033] Comparative Example 2 As Comparative Example 2, the thermally conductive silicone rubber sheet of Example 1 (mass 12960 g / m 2 , thickness 5 mm) was used.

[0034] A graph of the normal incidence sound absorption coefficient of the heat dissipating soundproof sheets obtained in Example 1 and Comparative Examples 1 and 2 is shown in Figure 4. A higher normal incidence sound absorption coefficient value indicates a better sound absorption coefficient. As is clear from Figure 4, the heat dissipating soundproof sheet of Example 1 had a lower sound absorption coefficient than the glass wool sheet of Comparative Example 1, but in the frequency range of 1.3 kHz or more, it was higher than the thermally conductive silicone rubber sheet of Comparative Example 2, confirming that this is a heat dissipating soundproof sheet with a good balance between thermal conductivity and soundproofing. [Industrial Applicability]

[0035] The heat-dissipating, soundproof sheet of the present invention is suitable for use in reducing noise from compressors of air conditioners for electric vehicles, compressors of heat pumps, and the like. [Explanation of symbols]

[0036] 1. Heat dissipation and soundproofing sheet 2a-2e Soundproof sheet layer 3a-3e Thermally conductive sheet layer 4,5 Base sheet 6. Cutter 11 Thermal conductivity measuring device 12 Sensors 13a, 13b Samples 14 Sensor tip 15 Electrode for applied current 16 Resistance electrode (temperature measurement electrode)

Claims

1. A heat-dissipating and soundproofing sheet including a soundproofing sheet layer and a thermally conductive sheet layer, the thermally conductive sheet layer is a sheet layer containing a matrix resin and a thermally conductive filler, The heat-dissipating and sound-proof sheet is characterized in that the sound-proof sheet layer and the heat-conductive sheet layer are laminated in a thickness direction of the heat-dissipating and sound-proof sheet.

2. The heat-dissipating and soundproofing sheet according to claim 1 , wherein the soundproofing sheet layer and the heat-conductive sheet layer are stacked in parallel.

3. The heat-dissipating soundproof sheet according to claim 1, wherein the soundproof sheet layer is at least one sheet layer selected from the group consisting of a glass wool sheet layer, a rock wool sheet layer, a ceramic fiber sheet layer, a synthetic fiber sheet layer, and a foamed resin sheet layer.

4. 2. The heat-dissipating and sound-proof sheet according to claim 1, wherein the sound-proof sheet layer has a thickness of 0.5 to 10 mm per layer.

5. 2. The heat-dissipating and sound-proof sheet according to claim 1, wherein the matrix resin is a cured silicone resin.

6. 2. The heat-dissipating and sound-proof sheet according to claim 1, wherein the thickness of each of the thermally conductive sheet layers is 0.5 to 5 mm.

7. The heat-dissipating and sound-proofing sheet according to claim 1, wherein the thermal conductivity of the thermally conductive sheet layer in accordance with ISO 22007-2:2008, hot disk method, is 0.5 W / m·K or more.

8. 2. The heat-dissipating and sound-proof sheet according to claim 1, wherein the thermally conductive sheet layer has a tack value of 0.3 N or more.

9. 2. The heat-dissipating and sound-proof sheet according to claim 1, wherein the thickness of the heat-dissipating and sound-proof sheet in the noise generation direction is 1 to 50 mm.

10. A method for producing the heat-radiating and soundproofing sheet according to any one of claims 1 to 9, a thermally conductive composition and a soundproof sheet are placed on a substrate sheet, and then another substrate sheet is placed on top of the thermally conductive composition and rolled to form a laminated single sheet of a soundproof sheet layer and a thermally conductive sheet layer; A plurality of the single-layer laminate sheets are laminated to form a multi-layer laminate sheet, A method for producing a heat-dissipating and sound-proof sheet, comprising cutting the multi-layer laminate sheet in the thickness direction to obtain a heat-dissipating and sound-proof sheet.

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