JP4631877B2 - Resin heat sink - Google Patents

Description

  The present invention relates to a heat sink made of a resin material and excellent in heat dissipation.

In the field of electronic equipment, heat dissipation of the heating element is an important issue, and a heat sink is used to effectively cool the element.
Conventional heat sinks use copper and aluminum materials to produce products by cutting, die casting or hot extrusion. There are also products with metal heat pipes installed to further improve heat dissipation. These metal heat sinks are heavy and hinder weight reduction. In addition, since the metal heat pipe is heavy and the internal structure needs to generate a capillary phenomenon, it has a complicated structure, so the price is high and the weight is heavy and it is difficult to make it thin.

There are also patents related to heat-dissipating parts in which carbon nanotubes are added to the resin, but there is no data on the actual heat-dissipating effect, and it is difficult to uniformly disperse carbon nanotubes in the resin. It was not obtained.
JP 2004-198098 A

  In addition, in order to enhance the heat dissipation effect of heat sinks with conventional copper and aluminum, it is necessary to make the fins thin and high, and increase the number of the fins. In order to produce a side effect, it is necessary to perform complete shielding in order to completely shield the electromagnetic wave generated inside the electronic device, which has been a factor that hinders downsizing of the electronic device. In particular, for shielding electromagnetic waves, there is a demand for shielding properties in a wide band, but there are many materials that exhibit shielding properties at a specific frequency, but a material that exhibits shielding properties in a wide band that exceeds 1 MHz to 1 GHz is found. It is not easy. Therefore, there has been a demand for a heat sink made of a material that is excellent in the effect of lowering heat and exhibits electromagnetic wave shielding properties in a wide band.

  Therefore, the present invention is a resin heat sink excellent in heat dissipation effect that replaces copper and aluminum, and is made of a material that has excellent electromagnetic shielding properties, particularly excellent shielding characteristics in a wide band exceeding 1 MHz to 1 GHz. It is an object to provide a heat sink.

  As a result of various studies to solve the above problems, the present inventors have mixed carbon material and ceramic powder and / or soft magnetic powder into the resin at a specific ratio, so that carbon is contained in the resin. The present invention has been completed by finding that the material can be uniformly dispersed and that the heat sink molded using this material has high heat dissipation and electromagnetic wave shielding properties.

  That is, the present invention is a heat sink having heat dissipation and electromagnetic wave shielding properties, wherein a part or all of the heat sink is formed of a resin material, and the resin material includes (a) a carbon material and (b ) The ceramic powder and / or the soft magnetic powder are uniformly dispersed, and the ratio of (a) in the resin material is 15% by volume or more and 60% by volume or less, and the ratio of (b) is 5% by volume. It is 40 volume% or less, and the sum total of (a) and (b) is 20 volume% or more and 80 volume% or less.

  By mixing the carbon material and the ceramic powder and / or soft magnetic powder in the resin in the above ratio, the carbon material having high thermal conductivity can be uniformly dispersed in the resin by the ceramic powder and / or soft magnetic powder. In addition, by forming a heat sink with this resin material, a heat sink excellent in heat dissipation and electromagnetic wave shielding can be provided. Moreover, since the heat sink concerning this invention is resin, even if it is complicated shape, shaping | molding is easy.

The carbon material (a) is preferably a carbon material having a thread shape (including a tube shape) having a thermal conductivity of 100 W / m · k or more, and particularly a pitch-like carbon fiber and a thread shape having a nanometer size in diameter. It is preferable to consist of a mixture of carbon nanomaterials.
By using a filamentous carbon material, the strength of the heat sink can be increased. In addition, by blending ceramic powder and / or soft magnetic powder, the carbon fibers are not oriented in one direction at the time of molding, and it is possible to achieve uniform strength improvement of the heat sink and uniform thermal conductivity and electromagnetic wave absorption. It becomes possible.
In particular, by uniformly dispersing pitch-based carbon fibers and carbon nanotubes with high thermal conductivity in the resin with ceramic powder and / or soft magnetic powder, it is possible to obtain a heat sink with better heat dissipation and electromagnetic wave shielding properties. . Although carbon nanotubes are difficult to disperse uniformly in the resin, they can be uniformly dispersed in the resin by using in combination with ceramic powder and / or soft magnetic powder.

Moreover, it is possible to further improve the heat diffusibility of the heat sink by mounting a heat transfer body made of a material having a thermal conductivity of 100 W / m · k or more on the heat source grounding surface of the heat sink.
Further, by providing a heat pipe mechanism with a refrigerant in the heat sink, it is possible to obtain a heat sink having further excellent heat dissipation. Since the heat pipe mechanism can be made of the same material as the resin material constituting the heat sink, the weight can be reduced, and even a complicated shape or thin structure can be easily formed.

  Since the heat sink according to the present invention is excellent in both heat dissipation and electromagnetic wave shielding in a wide band, the heat generating element can be effectively cooled and the adverse effects caused by electromagnetic waves can be reduced. Further, the weight can be reduced and the moldability is excellent.

The resin used in the present invention may be either a thermoplastic resin or a thermosetting resin. In the thermoplastic resin, a polyolefin-based resin, a polyamide-based resin, an elastomer-based (styrene-based, olefin-based, PVC-based, urethane-based, ester-based resin) , Amide-based) resin, acrylic resin, engineering plastic, etc. are used. In particular, polyethylene, polypropylene, nylon resin, ABS resin, acrylic resin, ethylene acrylate resin, ethylene vinyl acetate resin, polystyrene resin, polyphenylene sulfide resin, polycarbonate resin, polyester elastomer resin, polyamide elastomer resin, and liquid crystal polymer are selected. Among them, nylon resin, polyester elastomer resin, polyamide elastomer resin, ABS resin, polypropylene resin, polyphenylene sulfide resin, and liquid crystal polymer are preferable because of heat resistance and flexibility.
Moreover, an epoxy resin, a melamine resin, a phenol resin, a silicone resin, a urethane resin, etc. are used for a thermosetting resin. Of these, epoxy resins, silicone resins, and urethane resins are preferred because of their heat resistance and flexibility.
Dispersants, lubricants, and plasticizers may be added to these resins. In particular, the use of fatty acid esters and coupling agents in the dispersant increases the filling rate of carbon materials, ceramic materials, and soft magnetic materials. , The characteristics can be improved.

  In order to obtain a material having heat dissipation comparable to aluminum, the amount of resin is preferably 80% by volume or less of the total amount of resin material. A preferable amount of the resin is 20 to 60% by volume of the total amount of the resin material, more preferably 25 to 50% by volume, particularly preferably 30 to 45% by volume, and further preferably 35 to 45% by volume. If the particle size of the ceramic and soft magnetic powder is too small, it is necessary to increase the amount of resin added in order to ensure sufficient fluidity during molding, so the particle size of the ceramic powder and soft magnetic powder is 0.1 to 100 μm is preferred.

The carbon material according to the present invention is preferably a filamentous carbon material, and particularly preferably includes carbon fibers having a thermal conductivity of 100 W / m · k or more (more preferably 500 W / m · k or more). In order to maintain high thermal conductivity, it is preferable to use a carbon fiber having a diameter of 1 μm to 50 μm (more preferably a diameter of 3 μm to 20 μm) and an average length of 0.05 mm to 30 mm. . In particular, it is preferable to use carbon fibers having an average length of 0.1 mm to 25 mm, more preferably an average length of 0.3 mm to 10 mm. Moreover, as said carbon fiber, a pitch-type carbon fiber is preferable.
Furthermore, in addition to carbon fibers having a diameter of micrometer, it is preferable to use a carbon nanomaterial in the form of filaments (including a tube shape) having a diameter of nanometers. Examples of preferred carbon nanomaterials include carbon nanotubes or vapor grown carbon fibers. A preferable length of the filamentous carbon nanomaterial is 1 μm to 50 μm, and a preferable diameter is 5 nm to 100 nm.
In the present specification, among the filamentous carbon materials, those having a diameter of nanometer size (1 to 999 nm) are referred to as “carbon nanomaterials”, and those having a diameter of micrometer size or more (1 μm or more) Called carbon fiber.
The length of carbon fiber, carbon nanotube, etc. can be measured with an electron microscope, and the diameter can also be measured with an electron microscope. The average diameter and average length can be obtained by image analysis of an electron micrograph and calculating an average value.

The carbon material is preferably added so that the total amount is 15 volume% or more and 60 volume% or less of the total amount of the resin material. When the amount of carbon material added is less than 15% by volume, sufficient thermal conductivity cannot be obtained, and when it is more than 60% by volume, sufficient fluidity during molding cannot be obtained. In particular, 20 volume% or more and 50 volume% or less, and further 25 volume% or more and 45 volume% or less are preferable.
Moreover, in order to improve thermal conductivity, it is preferable to add a lot of carbon fibers and carbon nanotubes having a thermal conductivity of 500 W / m · k or more. Since both materials are very expensive, in consideration of cost, carbon fibers having a thermal conductivity of 100 W / m · k or more and less than 500 W / m · k may be mixed and used. When the amount of carbon material added is 100% by volume, the amount of carbon fiber having a thermal conductivity of 500 W / m · k or more is preferably 10% by volume or more, more preferably 15% by volume or more, and still more preferably 20%. Volume% or more. Moreover, when the resin material concerning this invention is 100 volume%, 5-50 volume% is preferable and, as for the quantity of the carbon fiber of 100 W / m * k or more in the resin material, 10-45 volume% is preferable. More preferred is 25 to 45% by volume. The amount of carbon nanotubes in the resin material is preferably 0.1% by volume or more and 10% by volume or less, preferably 0.2% by volume or more and 7% by volume or less from the viewpoint of thermal conductivity, electromagnetic wave shielding properties, uniform dispersibility in the resin, and cost. Volume% or less is more preferable, and 0.4 volume% or more and 5 volume% or less is particularly preferable.

  In a particularly preferable resin material, the carbon material is composed of a mixture of pitch-based carbon fibers and carbon nanotubes. When the resin material is 100% by volume, the proportion of pitch-based carbon fibers in the resin material is 5-50% by volume, carbon The proportion of nanotubes is preferably 0.1 to 10% by volume. More preferably, the proportion of pitch-based carbon fibers in the resin material is 25 to 45% by volume and the proportion of carbon nanotubes is 1 to 7% by volume, and particularly preferably the proportion of pitch-based carbon fibers in the resin material is 30 to 45% by volume. And the ratio of a carbon nanotube is 1-5 volume%. The pitch-based carbon fiber is preferably a pitch-based carbon fiber of 500 W / m · k or more.

As the ceramic powder, alumina, aluminum nitride, boron nitride, silicon nitride, silicon carbide, ferrite or the like is used depending on the purpose. The particle size of the powder is preferably 0.1 μm or more and 100 μm or less.
Soft magnetic powder is a powder made of a soft magnetic material. Soft magnetic materials are materials characterized by low coercive force and high magnetic permeability, especially iron, silicon steel, permalloy, sendust, permendur, soft ferrite, amorphous magnetic alloy, nanocrystal magnetic alloy, etc. Is used depending on the purpose. As the soft magnetic material, silicon steel, permalloy, sendust, permendur, soft ferrite, and amorphous magnetic alloy are particularly suitable in terms of cost and performance.

  The particle size of the ceramic powder and the soft magnetic powder is preferably 0.1 μm or more and 100 μm or less. When the particle diameter is smaller than 0.1 μm, the specific surface area increases, so that the amount that can be added to the resin is reduced. When the particle diameter is larger than 100 μm, the gap between the powders is increased, and the heat dissipation is reduced. In particular, from the viewpoint of characteristics, a preferable particle diameter is 0.3 μm or more and 50 μm or less, more preferably 0.5 μm or more and 40 μm or less, and further preferably 1 μm or more and 20 μm or less. The powder shape is preferably spherical in order to improve the fluidity of the material and increase the addition amount. In the present specification, the particle diameter of the powder means an average diameter measured by a laser diffraction particle size distribution measuring method.

  The ceramic material and soft magnetic powder contained in the resin material of the present invention may be one kind or plural kinds, and the ratio of the ceramic powder and / or soft magnetic powder in the resin material is 5 in total. The volume% is preferably 40% by volume or less, more preferably 7% by volume or more and 37% by volume or less, and particularly preferably 10% by volume or more and 35% by volume or less.

In the resin material of the present invention, a preferable ratio of the carbon material and the ceramic / soft magnetic powder is 80:20 to 20:80, a more preferable ratio is 70:30 to 30:70, and a particularly preferable ratio is 60:40 to 40. : 60.
The total proportion of the carbon material and the ceramic / soft magnetic powder in the resin material is preferably 20% by volume to 80% by volume, more preferably 35% by volume to 75% by volume, and particularly preferably 50% by volume or more. 70% by volume or less.

For mixing and dispersing the thermoplastic resin, the carbon material, the ceramic powder, and the soft magnetic powder, a heating kneader, a multi-screw extruder, a heating roll, or the like can be used. In addition, when a thermosetting resin is used as a base material, a mixer, a vacuum mixer, a multi-screw extruder, or the like can be used.
The obtained material can be molded into a desired shape by injection molding, sheet molding, extrusion molding or press molding. In the heat sink of the present invention, at least the fin portion is preferably made of the resin material, and more preferably the whole is made of the resin material. When the heat transfer body is provided on the heat source grounding surface of the heat sink, it is preferable that the whole except the heat transfer body is made of the resin material.

  In particular, when carbon fiber is used as the carbon material, the obtained heat sink contains carbon fiber, so that the strength is strong, and since it contains a lot of ceramic powder and / or soft magnetic powder, the carbon fiber is unidirectional during molding. Without orientation, it is possible to achieve uniform strength improvement of the heat sink and uniform thermal conductivity and electromagnetic wave absorption. That is, the carbon fibers are randomly present in the finely packed ceramics and / or soft magnetic powder, so that the orientation of the carbon fibers generated by sheet molding, injection molding, and extrusion molding can be reduced, and the heat sink using the carbon fibers. It is possible to reduce the direction dependency of the heat radiation effect that is likely to occur, and to obtain a uniform electromagnetic wave shielding effect.

  In the molding method, in particular, by using an injection molding method, it is possible to mold a heat sink having a three-dimensional complex shape with high dimensional accuracy at a low temperature as compared with a heat sink made of copper or aluminum as a raw material. In addition, a three-dimensional heat sink having a wall thickness of 1 mm or less can be easily molded as compared with a case where a copper or aluminum heat sink is molded by a die casting method.

In order to further increase the heat dissipation effect of the resin heat sink of the present invention, the heat source grounding surface, a heat transfer body made of a material having a thermal conductivity of 100 W / m · k or more, particularly copper, copper alloy having excellent thermal conductivity, By mounting a heat transfer body made of aluminum, aluminum alloy, aluminum nitride, alumina, carbon material or the like, the heat dissipation effect of the heat sink of the present invention can be further enhanced (see FIG. 2). In order to mount the heat transfer body on the resin heat sink which is the product of the present invention, when molding the heat sink, install it in the mold and pour the resin, or provide a space in the mounting part in advance to make the resin heat sink Any method of attaching the heat transfer body after forming the film may be used.
The larger the area of the heat transfer body, the higher the effect. Also, the heat transfer effect is better if the wall thickness is thicker, but if it is too thick, the thickness of the resin part becomes thin, the fluidity during molding deteriorates, and the product weight becomes heavy. It is better to keep the thickness to the same level. Further, from the viewpoint of electromagnetic wave leakage, the heat transfer body is preferably provided so as not to protrude from the resin portion.

  Further, by providing the resin heat sink of the present invention with a heat pipe mechanism made of a refrigerant, it is possible to obtain a heat sink with further excellent heat dissipation. An example of a heat sink having a heat pipe is shown in FIG. In conventional heat sinks made of metal, cutting of these heat pipe structures is indispensable, leading to a significant increase in cost and low mass production efficiency. According to the present invention, the heat pipe can be easily formed by using the same resin material as that of the resin heat sink of the present invention and bonding or fusing it after molding. Even when a metal heat pipe is used, it is possible to easily create an integrated heat sink by mounting and molding in a mold at the time of molding. The resin material of the present invention can suppress the coefficient of thermal expansion of the molding material to copper or aluminum or less by adding a large amount of carbon material, ceramic material and soft magnetic material having low thermal expansibility. This makes it possible to maintain stable heat dissipation even after molding.

  Hereinafter, based on an Example, the heat sink of this invention is demonstrated in detail.

[Examples 1 to 9] Evaluation of characteristics Sheets and heat sinks made of the resin material of the present invention, and comparative sheets and heat sinks were prepared, and electromagnetic wave shielding characteristics were examined using the sheets, and heat radiation characteristics were examined using the heat sinks.
Tables 1 to 5 show the compositions of the resin materials used in Examples and Comparative Examples.

Preparation of sheet and heat sink When using a thermoplastic resin, set the resin in advance in a 0.5 L heating kneader at 200 ° C. for polypropylene and 230 ° C. for nylon resin (nylon 12). After mixing and melting sufficiently for 10 minutes, the carbon material and ceramic powder or soft magnetic powder were gradually added and heated and kneaded for 1 hour.
The obtained molding material was used by measuring a 100 mm × 100 mm × 1.5 mm thickness sheet-like molded body for measurement of electromagnetic wave shielding using an injection molding machine having a clamping force of 100 tons. Regarding the measurement of heat dissipation characteristics, a heat sink molded body having a shape schematically shown in FIG. 1A was prepared and used (bottom plate 3: 50 mm × 35 mm × thickness 3 mm Fin 2: width 35 mm × height 30 mm × thickness 1 mm) Number of fins 2: 14).
In the case of using a silicone resin that is a thermosetting resin, a two-component addition type liquid silicone rubber was used in which 10 parts by weight of a curing agent was mixed with 100 parts by weight of the main agent. After adding carbon material and soft magnetic powder to this, stirring and mixing were performed for 30 minutes while vacuum defoaming at 25 ° C. using a 1 L vacuum defoaming mixer, and after taking out, it was applied to a polyethylene terephthalate (PET) film. After coating to a thickness of 1.5 mm, it was released from the PET film after 24 hours at 25 ° C., and left for 48 hours at 25 ° C., and then used for measurement of electromagnetic wave shielding properties. The size of the sheet was as described above (100 mm × 100 mm × thickness 1.5 mm).
Regarding the measurement of heat dissipation characteristics, a heat sink molded body having a shape schematically shown in FIG. 1A was prepared and used, as in the case of the thermoplastic resin. Apply a wax-type release material to the heat sink mold as a mother system, add each powder to the silicone rubber material, and stir and mix with a 1 L vacuum defoaming mixer while defoaming at 25 ° C. After taking out for a minute, the molding material was poured into a vacuum mold, left at 25 ° C. for 24 hours, taken out, held at 100 ° C. for 2 hours, and then measured.

  Ceramic powders (alumina powder, aluminum nitride powder) used in Examples and Comparative Examples were those having an average particle diameter of 10 μm. As the soft magnetic powder, sendust powder having a flat particle diameter of 10 μm and nickel powder of 3 μm were used. Carbon materials include Mitsubishi Chemical Corporation K6371T: 140 W / m · k, Mitsubishi Chemical Corporation K223HG: 700 W / m · k, or Nippon Graphite Fiber Co., Ltd. XN-100: 900 W / m · k pitch. -Based carbon fiber and Nanocarbon Technologies, Inc .: Multi-walled carbon nanotubes were used in combination.

Regarding the measurement of electromagnetic waves, an electromagnetic shielding characteristic of 10 MHz to 1 GHz was measured using a spectrum analyzer R3132 manufactured by Advantest.
As for the measurement of heat dissipation characteristics, as shown in FIG. 1B, an aluminum plate 5 is placed on a ceramic heater 4 having a 15 mm square and a thickness of 2 mm, the temperature of the heat source is raised to 100 ° C., and the temperature is soaked for 30 minutes. After confirming the above, the produced heat sink 1 was placed on the aluminum plate 5, and the temperature of the aluminum plate 5 was measured after 30 minutes.

The results are shown in the table below. The electromagnetic wave shielding characteristic shown in the table is transmission loss, and indicates a reduction value of the transmission amount in the sheet of the example or the comparative example with the transmission amount in the sheet made of only the corresponding resin as a reference value.

From the experimental results, it was confirmed that the heat sink according to the present invention was excellent in heat dissipation. Moreover, since the resin material which comprises a heat sink shows the high electromagnetic wave shielding characteristic, it turns out that the heat sink formed with the said resin material is excellent also in electromagnetic wave shielding capability. The resin materials used in Examples 1-9 is ^{2.1g / cm 3 ~3.6g / cm 3} , the weight of the heat sink as compared to copper or aluminum heat sink except that a silicone resin I was able to get it.

  Furthermore, as a result of examining the addition amount of each component, it is expected that the ratio of the carbon material in the resin material is less than 15% by volume, or the ratio of the ceramic powder and / or the soft magnetic powder is less than 5% by volume. The electromagnetic wave shielding characteristic and the heat radiation characteristic that were used were not obtained. Further, when the proportion of the carbon material in the resin material exceeds 60% by volume, or when the proportion of the ceramic powder and / or the soft magnetic powder exceeds 40% by volume, the viscosity of the resin material becomes high and molding processing can be performed. There wasn't.

[Examples 10 to 12] Preparation of heat sink having heat transfer body Using the same material as the resin material of Example 1 or 2, as shown schematically in FIG. 2, the heat source grounding surface is made of an aluminum plate or a copper plate. The heat sink 1 to which the heat transfer body 6 was attached was produced. The overall shape and size of the heat sink 1 was the same as in Example 1, and an aluminum plate or copper plate as the heat transfer body 6 having a size of 35 mm × 25 mm × thickness 0.5 mm was used. The heat sink was produced by insert molding by injection molding. The heat dissipation characteristics of each heat sink were measured by the same method as in Example 1.

  In addition, the heat dissipation characteristic only with said aluminum plate was 65 degreeC, and the heat dissipation characteristic only with a copper plate was 63 degreeC. From Examples 10-12, it turned out that the heat sink which was further excellent in heat dissipation can be obtained by mounting | wearing the resin heat sink of this invention with a heat conductive body with high heat conductivity.

Example 13 Production of Heat Sink Having Heat Pipe Mechanism As shown schematically in FIG. 3 using the resin material of Example 2, a heat sink 1 having a heat pipe mechanism 7 at the heat source grounding portion was produced. FIG. 3A is a side cross-sectional view, and FIG. 3B is a plan view of the heat pipe portion 7, and shows a space portion 8 constituting the cooling water channel in white. The manufacturing method is as follows. First, a portion with fins (the size of the bottom plate 3 and the fin 2 is the same as that of the first embodiment) and the heat pipe portion 7 installed below the bottom plate 3 are separately injection molded. The obtained two parts were assembled so as to have the shape shown in FIG. 3, and the two parts were bonded together by heat fusion.
A hole of about 1 mm communicating with the space portion 8 constituting the cooling water channel is made, and the air inside is exhausted. Then, pure water is injected so as to fill about 50% of the space portion 8, and after the injection, an epoxy adhesive is used. Used to close the hole. The heat dissipation characteristics of the obtained heat sink 1 with the heat pipe were measured by the same method as in Example 1. The heat radiation characteristic was 36 ° C., and a heat sink made of aluminum having no heat pipe shape and the same external shape was 40 ° C. Therefore, it was possible to obtain a heat sink excellent in heat dissipation. Also, since all of the fin part and the heat pipe part can be made of a resin material, it is lightweight and easy to mold, and can be easily manufactured as compared with a heat sink having a conventional heat pipe mechanism. It was.

  Since the heat sink according to the present invention has both excellent heat dissipation and electromagnetic wave shielding properties, it has been possible to integrate two components conventionally used, and to reduce the thickness of the product. Moreover, since it consists of a resin material, it is lightweight. Furthermore, since the resin material according to the present invention is excellent in moldability, a small and complex heat sink can be easily obtained by injection molding or the like.

1 shows an embodiment of a resin heat sink according to the present invention, in which A is a perspective view and B is a side view showing a state in which the heat sink of A is placed on a heat source. 1 shows a heat sink in which a heat transfer body is mounted on a heat source grounding surface, in which A is a side sectional view and B is a bottom view. 1 shows a heat sink having a heat pipe mechanism on a heat source grounding surface, wherein A is a side sectional view, B is a plan view of the heat pipe mechanism, and a cooling water channel portion is shown in white.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat sink 2 Fin 3 Bottom plate 4 Ceramic heater 5 Aluminum plate 6 Heat transfer body 7 Heat pipe 8 Space part (cooling water channel)

Claims (10)

A resin heat sink partially or entirely formed of a resin material,
In the resin material, (a) carbon material and (b) ceramic powder and / or soft magnetic powder are uniformly dispersed in the resin, and the ratio of (a) in the resin material is 15 to 60 volumes. %, The ratio of (b) is 5 to 40% by volume, and the sum of (a) and (b) is 20 to 80% by volume.   The resin heat sink according to claim 1, wherein the carbon material (a) includes a filamentous carbon material having a thermal conductivity of 100 W / m · k or more.   The resin heat sink according to claim 1 or 2, wherein the carbon material (a) includes pitch-based carbon fibers and thread-like carbon nanomaterials.   The carbon material (a) is composed of a mixture of pitch-based carbon fibers and carbon nanotubes, the proportion of pitch-based carbon fibers in the resin material is 5 to 50% by volume, and the proportion of carbon nanotubes is 0.1 to The resin heat sink according to claim 1, wherein the heat sink is 10% by volume.   The ceramic powder (b) is selected from the group consisting of alumina, aluminum nitride, boron nitride, silicon nitride, silicon carbide and ferrite, and the soft magnetic powder (b) is silicon steel, permalloy, sendust, perm The resin heat sink according to any one of claims 1 to 4, wherein the resin heat sink is selected from the group consisting of joules, soft ferrites, and amorphous magnetic alloys.   The average length of the pitch-based carbon fibers is 0.05 mm to 30 mm, and the ceramic powder and the soft magnetic powder have a particle size of 0.1 μm to 100 μm. 6. The resin heat sink according to item 1.   The resin-made product according to any one of claims 1 to 6, wherein a heat transfer body made of a material having a thermal conductivity of 100 W / m · k or more is attached to a heat source grounding surface of the heat sink. heatsink.   The resin heat sink according to claim 7, wherein the material constituting the heat transfer body is selected from the group consisting of copper, copper alloy, aluminum, aluminum alloy, aluminum nitride, and carbon material.   The resin heat sink according to any one of claims 1 to 8, further comprising a heat pipe mechanism using a refrigerant.   The resin heat sink according to any one of claims 1 to 9, wherein the resin heat sink is manufactured by extrusion molding, injection molding or press molding of the resin material.

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