Composition film and heat dissipation member

Abstract

To provide a composition film which suppresses lowering of heat dissipation property after repeated heat dissipation.SOLUTION: A composition film contains at least one kind of a compound selected from the group consisting of a resin and rubber, and a filler which is dispersed in the compound and has an average maximum length of 0.05 μm or more and 10 μm or less, and has density of 1.50 g / cm3 or more and 2.80 g / cm3 or less, wherein in space distribution of the filler existing in an evaluation region, an integral value of a statistic amount L (r) represented by expression (1), with a distance r between particles of 0.05 μm or more and 0.30 μm or less is 0 or more and 0.30 or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a composite film and a heat dissipation member. [Background technology]

[0002] Patent Document 1 discloses a filler-containing film having a filler dispersion layer in which filler is regularly arranged in an oil layer, in which the area occupancy of the filler in a planar view is 25% or less, the ratio La / D of the layer thickness La of the resin layer to the average diameter D of the filler is 0.3 or more and 1.3 or less, and the proportion of fillers that exist without contact with each other relative to the total number of fillers is 95% or more.

[0003] Patent document 2 also discloses a thermally conductive sheet that is composed of a binder and a thermally conductive filler and / or soft magnetic powder, and has thermal conductivity and electromagnetic interference suppression effects, as well as low contact thermal resistance on smooth and uneven surfaces.

[0004] Patent Document 3 also discloses an electronic device that includes a thermally conductive sheet between a heat-generating component and a heat-dissipating component, the thermally conductive sheet including rubber and a filler dispersed in the rubber, and in a binary image of a cross section of the rubber in the thickness direction, the average area ratio of large particle size fillers having a circle-equivalent diameter of 5 μm or more is in the range of 20% to 50%, the average degree of alignment fL of the large particle size filler is in the range of 0.00 to 0.15, the average area ratio of small particle size fillers having a circle-equivalent diameter of less than 5 μm is in the range of 10% to 30%, the average degree of alignment fS of the small particle size filler is in the range of 0.20 to 0.50, and the average alignment angle ΦS of the small particle size filler is in the range of 60° to 120°. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7307377 [Patent Document 2] Patent No. 4764220 [Patent Document 3] Patent Publication No. 2021-086920 Summary of the Invention [Problem to be solved by the invention]

[0006] The object of the present disclosure is to provide a composition film in which the average maximum length of the filler exceeds 10 μm and the density is 1.50 g / cm 3 The present invention provides a composition film that suppresses deterioration in heat dissipation properties after repeated heat dissipation, compared to a composition film in which the integral value of the statistic L(r) expressed by equation (1) is less than 0.30, and a composition film in which the integral value of the statistic L(r) expressed by equation (1) is more than 0.30, and a heat dissipation member including the composition film. [Means for solving the problem]

[0007] Means for solving the above problems include the following aspects. <1> at least one compound selected from the group consisting of resins and rubbers; A filler dispersed in the compound and having an average maximum length of 0.05 μm or more and 10 μm or less, Density is 1.50g / cm 3 More than 2.80g / cm 3 is as follows: A composition film in which, in the spatial distribution of the filler present in the evaluation area, the integral value of the statistic L(r) expressed by the following formula (1) when the interparticle distance r is 0.05 μm or more and 0.30 μm or less is 0 or more and 0.30 or less.

number

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[0008] <1> , <2> , <3> , <4> , <9> or <10> According to the invention, a composition film having a filler whose average maximum length exceeds 10 μm and a density of 1.50 g / cm 3 The present invention provides a composition film that suppresses the deterioration of heat dissipation properties after repeated heat dissipation, compared to a composition film in which the integral value of the statistic L(r) expressed by equation (1) is less than 0.30 and a composition film in which the integral value of the statistic L(r) expressed by equation (1) is more than 0.30. <5> or <6> According to the present invention, a composition film having excellent heat dissipation properties is provided compared to a composition film having a breakdown voltage of less than 5.0 kV / mm. <7> or <8> According to the invention, a composition film having excellent heat dissipation properties is provided compared to a composition film having a Shore hardness of more than 80 Hs. <11> or <12> According to the invention, a composition film having excellent heat dissipation properties is provided compared to a composition film having a thermal conductivity of less than 5.0 W / mK. <13> or <14> According to the invention, the thermal resistance is 1.0×10 -3 m 2 The composition film has excellent heat dissipation properties compared to the composition film with a K / W value exceeding 1000 kJ / W. <15> , <16> or <17> According to the invention, a composition film having a filler whose average maximum length exceeds 10 μm and a density of 1.50 g / cm 3 This provides a heat dissipation component that is less susceptible to deterioration in heat dissipation performance after repeated heat dissipation, compared to a heat dissipation component having only a composition film in which the integral value of the statistic L(r) expressed by equation (1) is less than 0.30, or a composition film in which the integral value of the statistic L(r) expressed by equation (1) is greater than 0.30. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present disclosure will be described. These descriptions and examples are intended to illustrate the embodiment, and are not intended to limit the scope of the embodiment.

[0010] In the present disclosure, a numerical range indicated using "to" indicates a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value of that numerical range may be replaced with a value shown in the examples. When embodiments of the present disclosure are described with reference to the drawings, the configuration of the embodiment is not limited to the configuration shown in the drawings. Furthermore, the sizes of the components in each drawing are conceptual, and the relative size relationships between the components are not limited to these. In the present disclosure, each component may contain multiple corresponding substances. When referring to the amount of each component in a composition in the present disclosure, if multiple substances corresponding to each component are present in the composition, the total amount of the multiple substances present in the composition is meant unless otherwise specified.

[0011] <Composition film> The composition film according to the embodiment of the present disclosure contains at least one compound selected from the group consisting of resins and rubbers, and a filler dispersed in the compound. The filler has an average maximum length of 0.05 μm or more and 10 μm or less. The composition film has a density of 1.50 g / cm 3 More than 2.80g / cm 3 The following is the result. Furthermore, in the spatial distribution of the filler present in the evaluation region of the composition film, the integral value of the statistic L(r) expressed by the below-described formula (1) when the interparticle distance r is 0.05 μm or more and 0.30 μm or less is 0 or more and 0.30 or less. In this disclosure, the evaluation region is defined as a range of 6.3 μm × 4.2 μm.

[0012] The composition film according to the embodiment of the present disclosure has the above-described configuration, and therefore the deterioration of heat dissipation properties after repeated heat dissipation is suppressed. The reason for this effect is presumed to be as follows.

[0013] As a composition film used as a heat dissipation component, a composition film having high thermal conductivity is used by adding a large amount of filler that contributes to thermal conduction to a binder such as resin or rubber. Such composition films are used, for example, in components that aim to reduce thermal resistance within a housing that has a heat source inside. However, composition films that contain a large amount of filler can sometimes experience a decrease in heat dissipation performance after repeated heat dissipation due to plastic deformation caused by heat.

[0014] In contrast, in the composition film according to the embodiment of the present disclosure, first, the density of the composition film is 1.50 g / cm 3 A high density of 1000 or more means that the film contains a large amount of filler. High density of the film increases the thermal conductivity and reduces the thermal resistance, and the film's specific heat reduces, making it easier for heat trapped in the heat dissipation object (such as an electronic component) to escape through the film in contact with the heat dissipation object. Furthermore, by using fillers with an average maximum length of 10 μm or less, the number density of the fillers is increased, which makes it easier for the fillers to form heat conduction paths within the composite film. Furthermore, the integral value of the statistic L(r) expressed by the formula (1) described below is 0.30 or less, and the filler dispersion state inside the composition film is maintained well. Therefore, although the composition film contains a large amount of filler, the filler dispersion state inside the composition film is maintained well, thereby reducing thermal plastic deformation. Even after repeated heat dissipation, the thermal contact resistance of the composition film is maintained low because thermal plastic deformation is suppressed. In other words, the deterioration of heat dissipation is suppressed, and the composition film can be used for a long period of time while maintaining high performance.

[0015] As described above, the composition film according to the embodiment of the present disclosure suppresses the deterioration of heat dissipation properties after repeated heat dissipation.

[0016] The composition film according to the embodiment of the present disclosure will be described in more detail below.

[0017] ·density The composition film has a density of 1.50 g / cm 3 More than 2.80g / cm 3 Density is 1.50 g / cm or less. 3 A high density of 2.80 g / cm or more means that the composition contains a large amount of filler, which improves the heat dissipation from the heat dissipation object (e.g., electronic components) that comes into contact with the composition film. 3 Being below this value means that the content of the compound is not too low, and the ability of the composition film to conform to the heat dissipation object, that is, the ability to increase the contact area, can be improved. The density of the composite film is further increased to 1.60 g / cm 3 More than 2.80g / cm 3 Preferably, it is 1.70 g / cm or less. 3 More than 2.60g / cm 3 More preferably, it is:

[0018] The density of the composition film is measured according to the underwater displacement method of JIS-K7112:1999 "Method for measuring density and specific gravity of plastics - non-foamed plastics." The immersion liquid is fresh distilled water containing 0.1% or less of a wetting agent to remove air bubbles.

[0019] The integral of the statistic L(r) In the composition film, in the spatial distribution of the filler present in the evaluation area (the evaluation area in this disclosure is defined as a range of 6.3 μm × 4.2 μm), the integral value of the statistic L(r) expressed by the following formula (1) when the interparticle distance r is 0.05 μm or more and 0.30 μm or less is 0 or more and 0.30 or less. When the integral value of the statistic L(r) is 0.30 or less, the filler is well dispersed inside the composition film, and a decrease in heat dissipation properties is suppressed even after repeated heat dissipation. The integral value of the statistic L(r) in the composition film is preferably 0 or more and 0.28 or less, and more preferably 0 or more and 0.26 or less.

[0020] Here, we will explain how to calculate the integral value of the statistic L(r) expressed by equation (1). First, the spatial distribution of the filler in the composition film is obtained by observing the cross section of the composition film at 20,000x magnification using a scanning electron microscope (Hitachi High-Technologies Corporation, model number: SU8010), and binarizing the resulting 256-level image using analysis software (free software "ImageJ") with a threshold value of 128. Then, the statistic L(r) value when the interparticle distance r is 0.05 μm or more and 0.30 μm or less is calculated in 0.05 μm increments based on the equation, and the integral value in the range of 0.05 μm or more and 0.30 μm or less is obtained, and this value is called the "L(r) integral value."

[0021] The number density λ of the particles (filler) in the following formula (2) can be determined from the observed two-dimensional image. The average maximum length of the fillers, which will be described later, is determined by determining the length of the longest part of each filler from the observed two-dimensional image and calculating the arithmetic mean of these lengths.

[0022]

number

[0023] (In formula (1), r represents the interparticle distance, and K(r) represents the K function K(r) of the Ripley function expressed by formula (2) below.)

[0024]

number

[0025] (In formula (2), 1(|X i -X j |≦r) denotes the indicator function, and X i and X j indicate the coordinates of point i and point j, respectively, and |X i -X j | is the coordinate X i and coordinate X j represents the Euclidean distance between the particles, r represents the interparticle distance, and s(|X i -X j|) indicates the edge correction coefficient s(x) of the evaluation area expressed by the following formula (3), and x = |X i -X j |, where N represents the total number of particles in the evaluation area, and λ represents the number density of particles in the evaluation area.

[0026]

number

[0027] (In the formula (3), L x and L y indicate the lengths (μm) of the sides of the evaluation area in the x-axis and y-axis directions, respectively, and x = |X i -X j | and X i and X j indicate the coordinates of point i and point j, respectively, and |X i -X j | is the coordinate X i and coordinate X j indicates the Euclidean distance between

[0028] In addition, in order to increase the dispersibility of the filler inside the composition film and set the integral value of the retention statistics L(r) within the above range, it is preferable to control the particle size of the filler and control the cohesive force of the filler inside the composition film when obtaining the composition film.

[0029] (filler) Average maximum length of filler The filler contained in the composition film has an average maximum length of 0.05 μm or more and 10 μm or less. When the average maximum length is 10 μm or less, the number density of the filler is increased, making it easier for a heat conduction path to be formed by the filler inside the composition film, and improving heat dissipation from a heat dissipation object (e.g., electronic components, etc.) that comes into contact with the composition film. On the other hand, when the average maximum length is 0.05 μm or more, it also makes it easier for a heat conduction path to be formed by the filler inside the composition film, and improving heat dissipation from a heat dissipation object (e.g., electronic components, etc.) that comes into contact with the composition film. The average maximum length of the filler is preferably 1.0 μm or more and 10 μm or less, and more preferably 2.0 μm or more and 6.5 μm or less.

[0030] Filler shape The shape of the filler contained in the composition film may be spherical, needle-like, or flat.

[0031] Filler material Examples of filler materials include carbon materials, ceramic materials, and metal oxide materials. Examples of carbon material fillers include carbon fibers such as carbon nanofibers and carbon nanotubes, graphite particles, and tabular graphite. Examples of ceramic material fillers include ceramic fibers, ceramic particles, and tabular ceramics such as aluminum nitride, boron nitride, and silicon carbide. Examples of metal oxide material fillers include acicular metal oxides, metal oxide particles, and tabular metal oxides such as alumina, boehmite (alumina monohydrate), silica, titania, zirconia, magnesium oxide, tin oxide, zinc oxide, and barium oxide.

[0032] In particular, from the viewpoint of improving heat dissipation, it is preferable to contain at least one selected from the group consisting of silicon carbide, aluminum nitride, and boron nitride as a filler, and it is more preferable to contain at least one selected from the group consisting of aluminum nitride and boron nitride as a filler.

[0033] (compound) Compound types The composition film contains at least one compound selected from the group consisting of resins and rubbers. Examples of the compound include resins such as acrylic resins, polyesters (especially aromatic polyesters), epoxy resins, polyimide resins, polyamide resins, polyamideimide resins, thermotropic liquid crystal polymers, fluororesins, and silicone resins, as well as rubbers such as fluororubbers, silicone rubbers, and fluorosilicone rubbers. One compound may be used alone, or two or more compounds may be used in combination. From the viewpoint of the heat resistance of the composition film, polyimide resins are preferred.

[0034] The content (vol %) of the compound contained in the composition film is preferably 20% by volume or more and 60% by volume or less, and more preferably 30% by volume or more and 40% by volume or less, from the viewpoint of flexibility and durability of the composition film.

[0035] (Physical properties of composition film) From the viewpoint of improving heat dissipation, the composition film preferably has a breakdown voltage of 5.0 kV / mm or more, more preferably 6.0 kV / mm or more. On the other hand, from the viewpoint of the trade-off relationship with thermal resistance, the upper limit of the breakdown voltage is preferably 20.0 kV / mm or less, more preferably 18.0 kV / mm or less, and even more preferably 11.5 kV / mm or less.

[0036] The breakdown voltage of the composition film is measured in accordance with JIS C2110-2:2016 (Part 2: Test by applying DC voltage).

[0037] The Shore hardness of the composition film is preferably 25Hs or more and 80Hs or less, and more preferably 25Hs or more and 75Hs or less. A Shore hardness of 80Hs or less improves the conformability to the heat dissipation object. A Shore hardness of 25Hs or more improves the strength of the composition film.

[0038] The Shore hardness of the composition film is measured using a micro rubber hardness tester (Type-C). The measurement conditions are in accordance with JIS Z2246:2000.

[0039] From the viewpoint of improving heat dissipation, the composition film preferably has a thermal conductivity of 5.0 W / mK or more, and more preferably 6.0 W / mK or more. On the other hand, from the viewpoint of the flexibility of the sheet, which reduces thermal resistance, the upper limit of the thermal conductivity is preferably 30.0 W / mK or less, more preferably 20.0 W / mK or less, and even more preferably 18.0 W / mK or less.

[0040] To measure the thermal conductivity of the composition film, the composition film was cut into a square of 2 mm in the axial direction and 2 mm in the circumferential direction, and this was used as the measurement sample. The thermal diffusivity was measured at room temperature (25°C ± 3°C) using a thermal diffusivity measuring device, ai-phase (Ai-phase Co., Ltd.), and the thermal conductivity (W / mK) was calculated by multiplying the thermal diffusivity by the specific heat and density.

[0041] The composition film has a thermal resistance of 1.0×10 -3 m 2 K / W or less is preferable, and 5.0 × 10 -4 m 2 It is more preferable that it is equal to or less than K / W.

[0042] The thermal resistance of the composition film is calculated by sandwiching the composition film between a cooling plate and a heater, applying a load, and calculating the thermal resistance value from the temperature difference between the top and bottom and the heat flow. The lower limit of the thermal resistance is 1.0 x 10 -8 cm 2 It is K / W.

[0043] The composite membrane according to the embodiment of the present disclosure may be a flat membrane or a tubular membrane. Examples of applications of the composite membrane according to the embodiment of the present disclosure include a sheet that is placed on a heat dissipation target such as an electronic device for the purpose of absorbing and releasing heat.

[0044] (heat dissipation material) A heat dissipation member according to an embodiment of the present disclosure includes the above-described composition film, and is installed on a heat dissipation target such as an electronic device for the purpose of absorbing and releasing heat.

[0045] The heat dissipation member may have the composition film as a single layer film, or may have a laminated film in which two or more composition films are laminated. In the case of a laminated film, the compounds of the layers may be different types of resin or rubber, and each layer may have a different role (for example, layers with different hardness may be laminated).

[0046] (Method of manufacturing composition film) As a method for producing a composition film according to an embodiment of the present disclosure, for example, a production method in which the following steps (1) to (3) are sequentially performed can be mentioned.

[0047] Step (1): A coating liquid is prepared by mixing a compound and a filler, and if necessary, a solvent or a dispersion medium is also mixed. Step (2): The coating liquid is applied onto a substrate and dried to form a coating film. Step (3): The coating film is baked to obtain a composition film.

[0048] By forming the substrate in step (2) into a cylindrical mold, a tubular composition film can be produced. [Example]

[0049] Hereinafter, the embodiments of the present invention will be described in detail with reference to examples, but the embodiments of the present invention are not limited to these examples in any way. In the following description, syntheses, treatments, manufacturing, etc. were carried out at room temperature (25°C ± 3°C) unless otherwise specified.

[0050] <Production of composite film> [Examples A1 to A8, Comparative Examples A1 to A4 (rubber)] The filler shown in Table 1 was added to the rubber (Si rubber) shown in Table 1 at the content shown in Table 1 and mixed, and the mixture was kneaded in a three-roll mill to prepare a coating liquid (A). The coating solution (A) was applied to the outer peripheral surface of an aluminum cylindrical mold (diameter 30 mm, width 420 mm) and dried at 100°C for 80 minutes. The cylindrical mold with the coating film was then placed in a heating furnace and fired at 380°C for 40 minutes. The amount of coating solution (A) applied was adjusted so that the average film thickness of the composition film was 100 μm. The fired film was pulled out of the cylindrical mold to obtain a composition film.

[0051] The details of the rubbers and fillers listed in Table 1 are as follows: (rubber) Si rubber (silicone rubber, manufactured by Shin-Etsu Chemical Co., Ltd., product name: X-34-2826-A / B) (filler) [Example A1] Aluminum nitride (average maximum length: 7 μm, manufactured by Toyo Aluminum Co., Ltd., product name: TFZ-A10P) [Example A2] Aluminum nitride (average maximum length: 3 μm, manufactured by Toyo Aluminum Co., Ltd., product name: TFZ-A05P) [Comparative Example A1] Aluminum nitride (average maximum length: 15 μm, manufactured by Toyo Aluminum Co., Ltd., product name: TFZ-A15P) ·[Comparative example A2] Aluminum nitride (average maximum length: 0.1 μm, manufactured by Toyo Aluminum Co., Ltd., product name: TFZ-N01P) [Examples A3 and A7] Silicon carbide (average maximum length: 2 μm, manufactured by Kojundo Chemical Laboratory Co., Ltd., product name: SII01PB) [Example A4] Boron nitride (average maximum length: 8 μm, manufactured by 3M Corporation, product name: Platelets CFP 012) [Examples A5, A6, A8, Comparative Example A3] Graphite (average maximum length: 6 μm, manufactured by Nippon Graphite Co., Ltd., product name: JB-5) ·[Comparative example A4] Graphite (average maximum length: 0.1 μm, manufactured by Nippon Techno Carbon Co., Ltd., product name: GF-130)

[0052] [Examples B1 to B20, Comparative Examples B1 to B12 (Resins)] The fillers shown in Tables 2 to 4 were added to the resins (acrylic resin, polyimide, aromatic polyester, or epoxy resin) shown in Tables 2 to 4 in the amounts shown in Tables 2 to 4, and mixed. The mixture was then kneaded using a three-roll mill to prepare coating solution (B). The coating liquid (B) was applied to the outer peripheral surface of an aluminum cylindrical mold (diameter 30 mm, width 420 mm) having a film on its surface from which the cured resin could be peeled off, and dried at a temperature of 115°C for 15 minutes. The cylindrical mold with the coating film was then placed in a heating furnace and baked at a temperature of 200°C for 2 hours. The amount of coating liquid (B) applied was adjusted so that the average film thickness of the composition film was 100 μm. The baked film was demolded from the cylindrical mold to obtain a composition film.

[0053] The details of the resins and fillers listed in Tables 2 to 4 are as follows. (resin) Acrylic resin (DIC Corporation, product name: ACRYDIC36-068) Polyimide (polyamic acid solution, solids content 18%, U-imide Varnish KX-R, manufactured by Unitika Ltd.) Aromatic polyester (manufactured by Sumitomo Chemical Co., Ltd., product name: Sumika Super) Epoxy resin (manufactured by Dai Nippon Paint Co., Ltd., product name: Eponix PH) (filler) [Examples B1, B6, B11, B16] Aluminum nitride (average maximum length: 7 μm, manufactured by Toyo Aluminum Co., Ltd., product name: TFZ-A10P) [Examples B2, B12, B17] Aluminum nitride (average maximum length: 1 μm, manufactured by Tokuyama Corporation, product name: HF-01) ·[Comparative examples B1, B4, B7, B10] Aluminum nitride (average maximum length: 0.8 μm, manufactured by Tokuyama Corporation, product name: HF-01D) [Examples B3 and B18] Boron nitride (average maximum length: 4 μm, manufactured by 3M Corporation, product name: Platelets CFP 003SF) [Examples B7 and B13] Boron nitride (average maximum length: 8 μm, manufactured by 3M Corporation, product name: Platelets CFP 012) [Examples B4, B9, B14, B19, Comparative Examples B8, B11] Graphite (average maximum length: 6 μm, manufactured by Nippon Graphite Co., Ltd., product name: JB-5) ·[Comparative examples B3, B6, B9, B12] Graphite (average maximum length: 0.1 μm, manufactured by Nippon Techno Carbon Co., Ltd., product name: GF-130) [Examples B5, B10, B15, B20] Silicon carbide (average maximum length: 2 μm, manufactured by Kojundo Chemical Laboratory Co., Ltd., product name: SII01PB) [Example B8, Comparative Example B2] CNF (carbon nanofiber, average maximum length: 1 μm, manufactured by RESONAC, product name: VGCF-H) [Comparative Example B5] CNF (carbon nanofiber, average maximum length: 6 μm, manufactured by RESONAC, product name: VGCF-H)

[0054] The composition films obtained in each example and comparative example were measured for density, integral value of statistic L(r), breakdown voltage, Shore hardness, thermal conductivity, and thermal resistance by the methods described above. The results are shown in Tables 1 to 4.

[0055] [Heat dissipation in long-term tests] For the composition films obtained in each example and comparative example, the thermal resistance was measured after a 200-hour heat cycle test at 125°C / -55°C relative to the thermal resistance value (T=0). Evaluation was made according to the following criteria. AA: Value between 90% and 100% A: Value between 80% and 90% B: Value between 60% and 80% C: Less than 60%

[0056] [Thermal resistance] The composition film obtained in each example and comparative example was sandwiched between a cooling plate and a heater, a load was applied, and the thermal resistance value was calculated from the temperature difference between the top and bottom and the heat flow. The lower limit of the thermal resistance value was 1.0 × 10 -8 cm 2 K / W. Evaluation was based on the following criteria. AA:5.0×10 -4 m 2 K / W or less A: 5.0 x 10 -4 m 2 K / W super 1.0×10 -3 m 2 K / W or less B: 1.0 x 10 -3 m 2 K / W super 5.0×10 -2 m 2 K / W or less C:5.0×10 -2 m 2 K / W super

[0057] [Suitable for heat dissipation materials] The evaluation was based on the following criteria. AA: Excellent heat dissipation in long-term tests, and meets all insulation and flexibility requirements A: Excellent heat dissipation in long-term tests, and satisfies insulation and flexibility requirements B: Heat dissipation is slightly poor in long-term tests C: Poor heat dissipation in long-term tests

[0058] [Table 1]

[0059] [Table 2]

[0060] [Table 3]

[0061] [Table 4]

[0062] As shown in Tables 1 to 4, it can be seen that the composition films of this example have a reduced deterioration in heat dissipation properties after repeated heat dissipation compared to Comparative Examples A1 to A4 and Comparative Examples B1 to B12, in which at least one of the average maximum length of the filler, the density of the composition film, and the integral value of the composition film statistics L(r) is outside the range of the present disclosure.

[0063] The composition film and the heat dissipation member according to the embodiment of the present disclosure include the following aspects. (((1))) at least one compound selected from the group consisting of resins and rubbers; A filler dispersed in the compound and having an average maximum length of 0.05 μm or more and 10 μm or less, Density is 1.50g / cm 3 More than 2.80g / cm 3 is as follows: A composition film in which, in the spatial distribution of the filler present in the evaluation area, the integral value of the statistic L(r) expressed by the following formula (1) when the interparticle distance r is 0.05 μm or more and 0.30 μm or less is 0 or more and 0.30 or less.

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[0064] According to the inventions of (((1)), (((2)), (((3)), (((4)), (((9))) or (((10)), a composition film in which the average maximum length of the filler exceeds 10 μm and the density is 1.50 g / cm 3The present invention provides a composition film that suppresses the deterioration of heat dissipation properties after repeated heat dissipation, compared to a composition film in which the integral value of the statistic L(r) expressed by equation (1) is less than 0.30 and a composition film in which the integral value of the statistic L(r) expressed by equation (1) is more than 0.30. According to the invention (((5))) or (((6))), a composition film is provided that has excellent heat dissipation properties compared to a composition film having a breakdown voltage of less than 5.0 kV / mm. According to the invention of (((7))) or (((8))), a composition film having excellent heat dissipation properties is provided compared to a composition film having a Shore hardness of more than 80 Hs. According to the invention of (((11))) or (((12))), a composition film having excellent heat dissipation properties is provided compared to a composition film having a thermal conductivity of less than 5.0 W / mK. According to the invention of (((13))) or (((14))), the thermal resistance is 1.0×10 -3 m 2 The composition film has excellent heat dissipation properties compared to the composition film with a K / W value exceeding 1000 kJ / W. According to the invention of (((15))), (((16))) or (((17))), a composition film in which the average maximum length of the filler exceeds 10 μm and the density is 1.50 g / cm 3 This provides a heat dissipation component that is less susceptible to deterioration in heat dissipation performance after repeated heat dissipation, compared to a heat dissipation component having only a composition film in which the integral value of the statistic L(r) expressed by equation (1) is less than 0.30, or a composition film in which the integral value of the statistic L(r) expressed by equation (1) is greater than 0.30.

Claims

1. at least one compound selected from the group consisting of resins and rubbers; A filler dispersed in the compound and having an average maximum length of 0.05 μm or more and 10 μm or less, Density is 1.50 g / cm ３ 2.80g / cm or more ３ is as follows: A composition film, wherein in the spatial distribution of the filler present in the evaluation region, the integral value of the statistic L(r) expressed by the following formula (1) when the interparticle distance r is 0.05 μm or more and 0.30 μm or less is 0 or more and 0.30 or less. [Equation 1] (In formula (1), r represents the interparticle distance, and K(r) represents the K function K(r) of the Ripley function expressed by formula (2) below.) [Equation 2] (In formula (2), 1(|X ｉ -X ｊ |≦r) denotes the indicator function, and X ｉ and X ｊ indicate the coordinates of point i and point j, respectively, and |X ｉ -X ｊ | is the coordinate X ｉ and coordinate X ｊ represents the Euclidean distance between the particles, r represents the interparticle distance, and s(|X ｉ -X ｊ |) indicates the edge correction coefficient s(x) of the evaluation area expressed by the following formula (3), and x = |X ｉ -X ｊ |, where N represents the total number of particles in the evaluation area, and λ represents the number density of particles in the evaluation area. [Equation 3] (In the formula (3), L ｘ and L ｙ indicate the lengths (μm) of the sides of the evaluation area in the x-axis and y-axis directions, respectively, and x = |X ｉ -X ｊ | and X ｉ and X ｊ indicate the coordinates of point i and point j, respectively, and |X ｉ -X ｊ | is the coordinate X ｉ and coordinate X ｊ This indicates the Euclidean distance between

2. The composition film according to claim 1 , wherein the average maximum length of the filler is 1.0 μm or more and 10 μm or less.

3. Density is 1.60 g / cm ３ 2.80g / cm or more ３ 2. The composition film of claim 1, wherein:

4. 2. The composition film according to claim 1, wherein the integral value of the statistic L(r) expressed by the formula (1) is 0 or more and 0.28 or less.

5. 2. The composition film according to claim 1, having a breakdown voltage of 5.0 kV / mm or more.

6. 6. The composition film according to claim 5, wherein the breakdown voltage is 6.0 kV / mm or more and 20.0 kV / mm or less.

7. 2. The composition film according to claim 1, having a Shore hardness of 25 Hs or more and 80 Hs or less.

8. The composition film according to claim 7, having a Shore hardness of 25 Hs or more and 75 Hs or less.

9. The composition film according to claim 1 , wherein the filler comprises at least one selected from the group consisting of silicon carbide, aluminum nitride, and boron nitride.

10. The composition film according to claim 9 , wherein the filler comprises at least one of aluminum nitride and boron nitride.

11. The composition film of claim 1 , having a thermal conductivity of 5.0 W / mK or more.

12. The composition film according to claim 11, having a thermal conductivity of 6.0 W / mK or more and 30.0 W / mK or less.

13. Thermal resistance is 1.0 x 10 －３ m ２ 10. The composition film of claim 1, wherein the tensile strength is less than or equal to 1000 kJ / W.

14. Thermal resistance is 5.0 x 10 －４ m ２ 14. The composition film of claim 13, wherein the tensile strength is less than or equal to 1000 kJ / W.

15. A heat dissipation member comprising the composition film according to any one of claims 1 to 14.

16. The heat dissipation member according to claim 15 , wherein the composition film is a single layer film.

17. The heat dissipation member according to claim 15 , wherein the composition film has a laminated film in which two or more layers are laminated.

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