Laminate, heat dissipation member and method for manufacturing the same, heat dissipation housing and method for manufacturing the same

Abstract

Provided is a laminate exhibiting good heat dissipation properties while achieving weight reduction. The laminate has at least one metal layer and at least one resin layer. The unit weight of the laminate is 2.0 kg / m2 or less, and the thermal diffusivity in a direction perpendicular to the lamination direction of the laminate is 10 × 10-6m2 / s or more.

Description

[Technical Field]

[0001] The present invention relates to a laminate, a heat dissipation member and a method for manufacturing the same, and a heat dissipation enclosure and a method for manufacturing the same. [Background technology]

[0002] In recent years, interest in global environmental issues has grown worldwide, and environmentally friendly vehicles equipped with secondary batteries, such as electric vehicles and hybrid vehicles, are becoming increasingly popular. Many of these vehicles use a system in which the direct current generated by the onboard secondary battery is converted to alternating current via an inverter, and the necessary power is then supplied to an AC motor to generate driving force. These vehicles also use electronic control units (ECUs) to electronically control the engine drive and driver assistance systems.

[0003] However, as electronic devices such as inverters and ECUs become smaller and more highly integrated, the amount of heat generated increases, resulting in a problem of temperature rise. Temperature rise in electronic devices can cause malfunctions. Therefore, various measures must be taken to suppress temperature rise in electronic devices.

[0004] One possible means for achieving this is to use SUS, which has excellent heat dissipation properties, as the housing, as shown in Patent Document 1, for example. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2020-172694 Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, attention is being paid to improving the fuel economy (driving distance per unit of power) from the viewpoint of extending the cruising distance of electric vehicles, etc. However, since the aforementioned SUS housing is relatively heavy, if electronic devices are housed in such a housing, the fuel economy of the electric vehicle, etc. is likely to decrease.

[0007] Furthermore, from the perspective of reducing the weight of electric vehicles and the like, the replacement of stainless steel housings with plastic housings is currently being considered. However, plastic housings have lower heat dissipation properties than stainless steel housings. Therefore, as the temperature of electronic devices increases, it is possible that the electronic devices may malfunction.

[0008] Therefore, an object of one embodiment of the present invention is to provide a laminate that is lightweight and has good heat dissipation properties. [Means for solving the problem]

[0009] As a result of intensive research, the present inventors have found that in order to reduce the weight and improve the heat dissipation of a three-dimensional molded product such as a housing, it is important to form a laminate having at least one metal layer and at least one resin layer, and to control the thermal diffusivity of the laminate in a direction perpendicular to the stacking direction within an appropriate range. The present invention has been completed based on the above findings, and is exemplified below. [1] A laminate having at least one metal layer and at least one resin layer, The unit weight of the laminate is 2.0 kg / m 2 and the thermal diffusivity of the laminate in the direction perpendicular to the lamination direction is 10 × 10 -6 m 2 / s or more, laminate. [2] The thermal diffusivity in the direction perpendicular to the lamination direction of the resin layer is 0.05×10 -6 ~0.70×10 -6 m 2 The laminate according to [1], wherein / s. [3] The laminate according to [1] or [2], wherein the resin layer contains a magnetic metal material. [4] The laminate according to any one of [1] to [3], wherein the metal layer contains at least one selected from copper, a copper alloy, aluminum, and an aluminum alloy. [5] A heat dissipation member comprising the laminate according to any one of [1] to [4]. [6] A method for producing a heat dissipation member, comprising the step of producing a heat dissipation member using the laminate according to any one of [1] to [4]. [7] A heat dissipation housing having the laminate according to any one of [1] to [4]. [8] A method for producing a heat dissipating enclosure, comprising a step of producing a heat dissipating enclosure using the laminate according to any one of [1] to [4]. [Effects of the Invention]

[0010] In one embodiment of the present invention, it is possible to achieve a reduction in weight while providing good heat dissipation properties. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram of a heat dissipation evaluation device used to evaluate the heat dissipation of sheet-like test specimens in Examples 1 to 5, Comparative Example 1, and Reference Example 1. FIG. [Figure 2] FIG. 1 is a schematic view of sheet-like test specimens of Examples 1 to 5, Comparative Example 1, and Reference Example 1 before three-dimensional molding. [Figure 3] FIG. 1 is a schematic diagram illustrating a method for producing a three-dimensional molded specimen from a sheet-like specimen in Examples 1 to 5 and Reference Example 1. [Figure 4] 1 is a schematic diagram of a heat dissipation evaluation device used to evaluate the heat dissipation of three-dimensional molded test specimens in Examples 1 to 5, Comparative Example 1, and Reference Example 1. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention is not limited to the following embodiments, and various modifications and variations of the components can be made without departing from the spirit of the invention. Furthermore, various inventions can be created by appropriately combining the multiple components disclosed in the embodiments.

[0013] [1. Laminate] In one embodiment, the laminate according to the present invention includes at least one metal layer and at least one resin layer. Since the metal layers and resin layers are alternately stacked in this laminate, the laminate can be made lighter than a single metal layer having the same thickness as the laminate. The laminate can be used as a heat dissipation component.

[0014] (unit weight) In one embodiment, from the viewpoint of weight reduction, the unit weight of the laminate is 2.0 kg / m 2 The laminate contains a resin layer with a relatively low unit weight, which allows for weight reduction. The upper limit of the unit weight is preferably 1.5 kg / m 2 Less than or equal to 1.0 kg / m, more preferably 1.0 kg / m 2 The unit weight is typically 0.1 kg / m or less as the lower limit. 2 or more typically 0.2 kg / m 2 That's all. Next, the unit weight can be measured by measuring the weight of a sheet sample cut into a 10 cm square and dividing the weight by the area.

[0015] (thermal diffusivity) In one embodiment, from the viewpoint of ensuring good heat dissipation when formed into a three-dimensional molded product, the thermal diffusivity of the laminate in a direction perpendicular to the lamination direction is 10×10 -6 m 2 The lower limit of the thermal diffusivity is preferably 15×10 -6 m 2 / s or more, preferably 20 × 10 -6 m 2 / s or more. In addition, taking into consideration that the heat dissipation property tends to saturate when the thermal diffusivity exceeds a certain value, the upper limit is typically 140 × 10 -6 m 2 / s or less. In this invention, thermal diffusivity is an index calculated by dividing thermal conductivity by specific heat and density, and indicates the rate at which a temperature gradient within a material is alleviated. In other words, even if the thermal conductivity is high, if the specific heat or density of a material is high, the temperature change will be small even when a certain amount of heat is applied. In particular, when different materials are combined, as in the present laminate, heat dissipation cannot be evaluated using thermal conductivity alone. However, by evaluating the thermal diffusivity in the direction perpendicular to the stacking direction of the entire laminate, it is possible to evaluate the heat dissipation ability of dispersing hot spots. The inventors have found that while there is no correlation between the thermal diffusivity in the direction perpendicular to the stacking direction of a laminate in sheet form, there tends to be a correlation in three-dimensional molded products. The inventors speculate that this is because, while the temperature change in a sheet-shaped sample is dominated by thermal conduction within the sheet, in three-dimensional molded products, the influence of thermal diffusivity is greater due to the influence of heat transfer between the heat source and the air in addition to thermal conduction.

[0016] Next, the thermal diffusivity was measured as follows. The laminate was used as a sample, and the temperature was measured using a thermophysical property measuring device, Thermowave Analyzer TA35 Ultimate (manufactured by Bethel Co., Ltd.) or an equivalent device. Next, a periodic heating source Poe iωt The surface of the sample for measuring the thermal diffusivity κ is spot heated at room temperature (normal temperature) +10°C. The AC component of the temperature at the heating point is T ac =T0e iωt It is expressed as follows: Periodic heating source P0e iωt The temperature propagation induced in the surroundings by the temperature gradient can be expressed by the following number I. Note that the symbols in the following numbers I to V have the following meanings. κ: Thermal diffusivity [m 2 / s] f: Heating frequency [Hz] a: Distance from the heat source - gradient of the phase graph [rad. / m] θ: Phase [rad.] r: distance from heat source [m] μ: Thermal diffusion length [m] ω: Angular frequency [rad. / s] T: Temperature [K] i: imaginary number t: time [s] k: wave number of the temperature wave [1 / m] π: Pi P: Laser power ρ: Density c: specific heat

[0017]

number

[0018] The wave number k of the temperature wave in the above number I is expressed by the following number II.

[0019]

number

[0020] Therefore, the phase θ in the above equation I is expressed by the following equation III.

[0021]

number

[0022] Based on the above equation III, the results of measurements taken in the direction perpendicular to the thickness direction (stacking direction) of the sample are analyzed. Next, let r in the above equation III be the distance l from the heating point, and plot the distance l on the horizontal axis and the phase θ on the vertical axis. Here, the slope a of the obtained graph is given by the following equation IV.

[0023]

number

[0024] Therefore, the thermal diffusivity κ is expressed as the following number V.

[0025]

number

[0026] (Layer structure) Examples of the layer structure of the laminate include the following. (1) When the laminate has a two-layer structure, for example, a metal layer / resin layer structure can be mentioned. (2) When the laminate has a three-layer structure, examples include metal layer / resin layer / metal layer, resin layer / metal layer / resin layer, resin layer / metal layer / metal layer, and metal layer / resin layer / resin layer. (3) When the laminate has a four-layer structure, examples include metal layer / metal layer / metal layer / resin layer, metal layer / metal layer / resin layer / metal layer, metal layer / metal layer / resin layer / resin layer, metal layer / resin layer / metal layer / resin layer, metal layer / resin layer / metal layer / resin layer, and metal layer / resin layer / resin layer / metal layer. (4) When the laminate has a five-layer structure, for example, metal layer / resin layer / metal layer / resin layer / metal layer, resin layer / metal layer / resin layer / metal layer / resin layer, metal layer / metal layer / metal layer / metal layer / resin layer, metal layer / metal layer / metal layer / metal layer / resin layer, metal layer / metal layer / metal layer / resin layer / metal layer, metal layer / metal layer / metal layer / resin layer / resin layer, metal layer / metal layer / resin layer / metal ...resin layer / metal layer, metal layer / resin layer / metal layer, metal layer / resin layer / metal layer Examples include metal layer / metal layer / resin layer, metal layer / resin layer / metal layer / resin layer / metal layer, metal layer / resin layer / metal layer / resin layer / resin layer, metal layer / resin layer / metal layer / resin layer / resin layer, metal layer / resin layer / resin layer / metal layer / resin layer, metal layer / resin layer / resin layer / resin layer / metal layer, metal layer / resin layer / resin layer / resin layer / resin layer, resin layer / metal layer / metal layer / resin layer, resin layer / metal layer / metal layer / resin layer / resin layer, resin layer / metal layer / metal layer / resin layer / resin layer, resin layer / resin layer / metal layer / resin layer, resin layer / resin layer / metal layer / resin layer, and resin layer / resin layer / resin layer / metal layer / resin layer. (5) When the laminate has six layers, for example, metal layer / resin layer / metal layer / resin layer / metal layer / resin layer, metal layer / metal layer / metal layer / metal layer / metal layer / resin layer, metal layer / metal layer / metal layer / metal layer / resin layer / metal layer, metal layer / metal layer / metal layer / metal layer / resin layer / metal layer, metal layer / metal layer / metal layer / metal layer / resin layer / resin layer, metal layer / metal layer / metal layer / resin layer / metal layer, metal layer / metal layer / metal layer / resin layer / metal layer, metal layer / metal layer / metal layer / resin layer / metal layer, metal layer / metal layer / metal layer / resin layer / resin layer / metal layer, metal layer / metal layer / metal layer / resin layer / resin layer / resin layer, metal layer / metal layer / resin layer / metal layer / metal layer / resin layer, metal layer / metal layer / resin layer / metal layer / resin layer / metal layer, metal layer / metal layer / resin layer / metal layer / resin layer / resin layer, metal layer / metal layer / resin layer / resin layer / metal layer / metal layer, metal layer / metal layer / resin layer / resin layer / metal layer / resin layer, metal layer / metal layer / resin layer / Resin layer / resin layer / metal layer, metal layer / metal layer / resin layer / resin layer / resin layer / resin layer, metal layer / resin layer / metal layer / metal layer / metal layer / resin layer, metal layer / resin layer / metal layer / metal layer / resin layer / metal layer, metal layer / Resin layer / metal layer / resin layer / resin layer / metal layer, metal layer / resin layer / resin layer / resin layer / resin layer / metal layer, resin layer / metal layer / metal layer / metal layer / metal layer / resin layer, resin layer / metal layer / metal layer / metal layer / resin layer / tree Examples of such layers include resin layer / metal layer / metal layer / resin layer / resin layer / resin layer, resin layer / metal layer / metal layer / resin layer / metal layer / resin layer, resin layer / metal layer / resin layer / metal layer / resin layer, resin layer / metal layer / resin layer / metal layer / resin layer, resin layer / metal layer / resin layer / metal layer / resin layer / resin layer, resin layer / metal layer / resin layer / resin layer / resin layer, resin layer / metal layer / resin layer / resin layer / resin layer, resin layer / metal layer / resin layer / resin layer / metal layer / resin layer, and resin layer / resin layer / metal layer / resin layer / resin layer. (6) When the laminate has a seven-layer structure, examples include resin layer / metal layer / resin layer / resin layer / resin layer / metal layer / resin layer, resin layer / metal layer / resin layer / metal layer / resin layer, and metal layer / resin layer / metal layer / resin layer / metal layer / resin layer / metal layer / resin layer.

[0027] (total thickness) From the viewpoint of formability, the thickness of the laminate is preferably 70 μm or more, more preferably 100 μm or more, and even more preferably 200 μm or more, but from the viewpoints of light weight and drilling processability, the thickness of the laminate is preferably 2000 μm or less, more preferably 1000 μm or less, and even more preferably 700 μm or less. The thickness of the laminate can be measured using a constant pressure thickness tester (THICKNESS METER B-1, manufactured by Toyo Seiki Seisakusho Co., Ltd.) in accordance with Method A of JIS K 6250:2019, by averaging the measured values ​​at four points on the sheet sample surface. The measurement can be performed with an indenter diameter of 5 mm and a pressure of 0.196 N applied to the indenter.

[0028] The ratio (M / R) of the total thickness (M) of the metal layers to the total thickness (R) of the resin layers can be set as appropriate, but from the viewpoint of moldability, it is, for example, 0.05 to 0.40.

[0029] (Lamination method) The resin layer and the metal layer may be laminated by using an adhesive between them, or by thermocompression bonding of the resin layer to the metal layer without using an adhesive. Although a method of simply stacking them without using an adhesive is also possible, in consideration of the integrity of the laminate, it is preferable to join at least the edges (for example, each side if the laminate is rectangular) with tape, adhesive, or by thermocompression bonding. The adhesive is not particularly limited, but examples thereof include acrylic resin-based, epoxy resin-based, urethane-based, polyester-based, silicone resin-based, vinyl acetate-based, styrene-butadiene rubber-based, nitrile rubber-based, phenolic resin-based, and cyanoacrylate-based adhesives, and from the viewpoints of ease of production and cost, urethane-based, polyester-based, and vinyl acetate-based adhesives are preferred.

[0030] <Metal layer> The material of the metal layer is not particularly limited, but it is preferable that the metal layer contains at least one material selected from the group consisting of copper, copper alloy, aluminum, and aluminum alloy. 6Materials with a value of S / m or higher are desirable. These are preferable from a practical standpoint.

[0031] (Thickness) The lower limit of the thickness per layer is, for example, 4 μm or more, and for example, 10 μm or more, while the upper limit of the thickness per layer is, for example, 70 μm or less, and for example, 50 μm or less. The thickness of the metal layer can be measured in the same manner as the thickness of the laminate. When measuring the thickness of the metal layer in the laminate, the thickness cross section can be observed using an SEM or the like.

[0032] In one embodiment, when multiple metal layers are formed, all the metal layers may be made of the same material, or different materials may be used for each layer, and all the metal layers may have the same thickness, or different thicknesses may be used for each layer.

[0033] In one embodiment, the total thickness of the metal layers is, for example, 4 to 420 μm. The lower limit of the total thickness is, for example, 10 μm or more, and for example, 30 μm or more, while the upper limit of the total thickness is, for example, 110 μm or less, and for example, 70 μm or less.

[0034] The metal layer is not particularly limited in shape, but examples include metal foil. When copper foil is used as the metal foil, a high copper purity is preferred because it improves shielding properties, with the purity being preferably 99.5% by mass or higher, more preferably 99.8% by mass or higher. Examples of copper foil that can be used include rolled copper foil, electrolytic copper foil, and metallized copper foil, but rolled copper foil is preferred because of its excellent formability. When alloying elements are added to copper foil to produce a copper alloy foil, the total content of these elements and unavoidable impurities should be less than 0.5% by mass. In particular, it is preferable for the copper foil to contain a total of 50 to 2000 ppm by mass of at least one element selected from tin, manganese, chromium, zinc, zirconium, magnesium, nickel, silicon, and silver, and / or 10 to 50 ppm by mass of phosphorus, because this improves elongation compared to pure copper foil of the same thickness.

[0035] (treated membrane) From the viewpoint of improving heat dissipation, the treated film is formed on at least one surface of the metal layer, and may further include, for example, one or more selected from an electromagnetic wave absorption auxiliary film of an alloy containing copper, a heat-resistant film, a rust-proof film, and a weather-resistant film. Examples of heat-resistant treated heat-resistant films include plating films and vapor-deposited films containing cobalt or nickel. Examples of rust-proof treated anti-corrosion films include inorganic plating films such as zinc or chromium, vapor-deposited films, and organic films such as benzotriazole. Examples of silane-coupling treated weather-resistant films include organic coating films containing a silane coupling agent. That is, the treated film may further include one or more elements selected from zinc, molybdenum, tin, phosphorus, tungsten, chromium, and silicon in addition to copper, cobalt, and nickel. The treatment film interposed between the metal layer and the resin layer can also increase the adhesion between the metal layer and the resin layer, and can also improve the shielding properties.

[0036] The electromagnetic wave absorbing auxiliary film can be produced by known methods, such as plating, metal vapor deposition, sputtering, etc. Among these, a method of forming an electromagnetic wave absorbing auxiliary film made of copper, cobalt, and nickel by plating the surface of a metal layer will be described below as an example. In the plating process for forming the auxiliary electromagnetic wave absorbing film, a particle film made of copper, cobalt, and nickel is formed on at least one surface of the metal layer.

[0037] (Plating conditions (roughening plating): copper, cobalt and nickel alloy plating) An example of the plating conditions for copper, cobalt and nickel is as follows. Solution composition: Copper 10-20g / L, Cobalt 5-15g / L, Nickel 5-15g / L pH: 2-3 Liquid temperature: 30~50℃ Current density: 10~60A / dm 2 Coulomb amount: 10~48As / dm 2

[0038] In this case, the roughening plating treatment can be carried out in multiple stages under the above plating treatment conditions.

[0039] In the heat-resistant treatment, at least one of the following heat-resistant films 1 and 2 can be further formed on the aforementioned electromagnetic wave absorbing auxiliary film. The plating conditions and vapor deposition conditions are shown below.

[0040] (Plating conditions for heat-resistant film 1) (Co-Ni plating: cobalt-nickel alloy plating) Solution composition: Nickel 5-20g / L, Cobalt 1-8g / L pH: 2-3 Liquid temperature: 40~60℃ Current density: 10~30A / dm 2 Coulomb amount: 2 to 20 As / dm 2

[0041] (Plating conditions for heat-resistant film 2) (Ni-Zn plating: nickel-zinc alloy plating) Solution composition: Nickel 2-30g / L, zinc 2-30g / L pH: 3-4 Liquid temperature: 30~50℃ Current density: 1~10A / dm 2 Coulomb amount: 0.5 to 2 As / dm 2

[0042] In the rust prevention treatment, the following rust prevention film and / or weather-resistant film can be further formed on the aforementioned electromagnetic wave absorbing auxiliary film or heat-resistant film. The respective conditions are shown below.

[0043] (Anti-rust coating plating conditions) Solution composition: Potassium dichromate 1-10g / L, zinc 0.2-0.5g / L pH: 3-4 Liquid temperature: 50~70℃ Current density: 0~2A / dm 2 (0A / dm2 is for immersion chromate treatment.) Coulomb quantity: 0 to 2 As / dm 2 (0As / dm 2 is for immersion chromate treatment.)

[0044] (Types of weather-resistant films (silane coupling films)) For example, an aqueous solution of diaminosilane or epoxysilane can be applied. In addition, when a metal film such as a heat-resistant film or a plating film is formed by vapor deposition (dry plating) such as sputtering, or when a metal film such as a heat-resistant film or a plating film is formed by plating (wet plating), and the metal film such as a heat-resistant film or a plating film is formed by normal plating (smooth plating, i.e., plating performed at a current density less than the limiting current density), the metal film or plating film does not affect the surface shape of the copper foil. The limiting current density varies depending on the metal concentration, pH, solution supply rate, electrode distance, and plating solution temperature, but in the present invention, the limiting current density is defined as the current density at the boundary between normal plating (a state in which the plated metal is deposited in the form of a film) and roughened plating (burnt plating, a state in which the plated metal is deposited in the form of crystals (spherical, needle-like, frost-like, etc.), with unevenness), and the limiting current density is the current density (visually determined) at the limit at which normal plating is obtained in a Hull cell test (just before burnt plating occurs). Specifically, the metal concentration, pH, and plating solution temperature are set to the plating production conditions, and a Hull Cell test is performed. The state of metal layer formation (whether the plated metal is deposited in layers or formed in crystals) is then investigated for that plating solution composition and plating solution temperature. Based on a current density chart produced by Yamamoto Plating Tester Co., Ltd., the current density at the boundary between normal plating and roughened plating is determined from the test piece's position on the test piece. The current density at that boundary is then defined as the limiting current density. This determines the limiting current density for that plating solution composition and plating solution temperature. Generally, a shorter electrode distance tends to result in a higher limiting current density. The method of the Hull Cell test is described, for example, in "Plating Practice Reader" by Kiyoshi Maruyama, published by Nikkan Kogyo Shimbun on June 30, 1983, pages 157 to 160. In order to perform plating at a current density lower than the limiting current density, the current density during plating was set to 20 A / dm 2 It is preferable that the current is less than 10A / dm 2 It is more preferable to set it to 8A / dm or less. 2 It is more preferable that: Furthermore, the anti-rust film and weather-resistant film are extremely thin and do not affect the surface shape of the copper foil.

[0045] <Resin layer> From the viewpoint of controlling the thermal diffusivity in the direction perpendicular to the stacking direction in the laminate, the resin layer is preferably made of a material having a thermal diffusivity of, for example, 0.05×10 -6 m 2 / s~0.70×10 -6 m 2 It is preferable to use a resin with a thermal diffusivity of 0.68×10 / s as the upper limit. -6 m 2 / s or less. The lower limit of the thermal diffusivity is, for example, 0.05 × 10 -6 m 2 / s or more, for example, 0.07 × 10 -6 m 2 / s or more. The thermal diffusivity can be measured by the method described above.

[0046] The resin layer may further contain a magnetic metal material. For example, a composite sheet may be used in which the magnetic metal material and a resin are mixed and dispersed and integrally molded. Resins contained in the composite sheet include natural resins and synthetic resins, with synthetic resins being preferred from the viewpoint of processability. Fiber reinforcement materials such as carbon fiber, glass fiber, and aramid fiber may also be mixed into these materials. As for the synthetic resin, any resin having the above-mentioned thermal diffusivity can be used appropriately.

[0047] The composite sheet can be laminated to a resin layer or a metal layer in the form of a film or fiber. The composite sheet can be obtained by applying a mixed composition of an uncured magnetic metal material and a resin to a resin substrate having a release layer, curing the mixture, and then peeling it off from the resin substrate. For example, the composite sheet can also be formed by applying a mixed composition of an uncured magnetic metal material and a resin to the surface of a resin layer, the surface of a metal layer, or the aforementioned treatment film, and then curing the mixture. For ease of production, it is preferable to make the composite sheet affixable to the surface of a resin layer, the surface of a metal layer, or the treatment film described below. The volume ratio of resin to magnetic metal material in the composite sheet is, for example, 75:25 to 1:99. The volume ratio of resin to magnetic metal material can be calculated, for example, by calculating the area ratio of the magnetic metal material on the surface perpendicular to the thickness direction of the composite sheet by SEM observation, and also by calculating the thickness ratio of the magnetic metal material to the composite sheet thickness in the thickness direction by SEM observation, and then calculating the volume ratio of the magnetic metal material in the composite sheet from the product of these, and then calculating the volume ratio as resin:magnetic metal material = (100 - volume ratio of magnetic metal material): volume ratio of magnetic metal material. The composite sheet may further contain conductive particles or conductive fibers other than the magnetic metal material, provided that the present invention is not impaired. Any known metal species having good conductivity can be used for the conductive particles or conductive fibers, including copper, copper alloys, aluminum, aluminum alloys, and carbon. In this case, the mass ratio of the resin to the conductive particles or conductive fibers is, for example, 70:30 to 1:99.

[0048] The magnetic metal material preferably contains at least one selected from nickel, iron, permalloy (Ni-Fe alloy), silicon iron, permendur, sendust (Fe-Si-Al alloy), soft ferrite, Fe-based amorphous, Co-based amorphous, and nanocrystal. It is presumed that the higher the filling rate of these materials when combined, the better the heat dissipation properties of the laminate laminated with the metal layer.

[0049] (Thickness) The lower limit of the thickness per layer is, for example, 5 μm or more, and for example, 10 μm or more, while the upper limit of the thickness per layer is, for example, 300 μm or less, and for example, 200 μm or less. The thickness of the resin layer can be measured in the same manner as the thickness of the laminate. When measuring the thickness of the resin layer in the laminate, the thickness cross section can be observed using an SEM or the like.

[0050] In one embodiment, when a plurality of resin layers are formed, all the resin layers may be made of the same material, or different materials may be used for each layer.Furthermore, all the resin layers may have the same thickness, or different thicknesses may be used for each layer.

[0051] In one embodiment, the total thickness of the resin layers is, for example, 10 to 1200 μm. The lower limit of the total thickness is, for example, 10 μm or more, and for example, 20 μm or more, while the upper limit of the total thickness is, for example, 1200 μm or less, and for example, 1000 μm or less.

[0052] [2. Heat dissipation materials] In one embodiment, the heat dissipation member according to the present invention has the above-described laminate. The heat dissipation member according to the present invention can also be used for electromagnetic wave shielding.

[0053] In one embodiment, the method for manufacturing the heat dissipation member includes a step of manufacturing the heat dissipation member using the laminate described above. The manufacturing method can manufacture the heat dissipation member by known processing means.

[0054] [3. Heat dissipation housing] In one embodiment, the heat dissipating housing according to the present invention includes the laminate described above. The heat dissipating housing may further include a housing main body capable of housing an electronic device such as an inverter or an ECU. For example, the housing main body may be made of resin, with the laminate serving as the inner surface. In this case, the heat dissipating housing can be insert-molded with the laminate as an insert part. With these configurations, heat generated by the electronic device housed in the heat dissipating housing is transferred to the laminate and dissipated to the outside via the laminate. As a result, temperature rise in the electronic device is suppressed, preventing malfunction of the electronic device. Furthermore, the heat dissipation housing may have a housing body that is a laminated body. The heat dissipation housing of the present invention can also be used for electromagnetic wave shielding.

[0055] In one embodiment, the method for manufacturing the heat dissipating housing includes a step of manufacturing the heat dissipating housing using the laminate described above. The manufacturing method can manufacture the heat dissipating housing by known processing means. [Example]

[0056] The present invention will be specifically described based on Examples, Comparative Examples, and Reference Examples. The following Examples, Comparative Examples, and Reference Examples are merely specific examples intended to facilitate understanding of the technical content of the present invention, and the technical scope of the present invention is not limited by these specific examples.

[0057] [Laminate fabrication] In Examples 1 to 5, metal layers 1 and 2 and resin layer 1 were prepared as materials in the order of composition shown in Table 1. Metal layer 2 was annealed at a material temperature of 200°C for a heating retention time of 1 hour, and metal layer 1 was annealed at a material temperature of 200°C for a heating retention time of 1 hour after providing each treatment film, as described below. Metal layers 1 to 3 in Table 1 are as follows: As resin layer 1, a commercially available resin film (nominal thickness 100 μm) was used. Metal layer 1: Copper foil (nominal thickness 18 μm, tough pitch copper (JIS H 3100 (C1100): 2018 standard), manufactured by JX Nippon Mining & Metals Corporation) Metal layer 2: Aluminum foil (nominal thickness 35 μm, A1050 (JIS H 4000:2017 standard), commercially available product) Metal layer 3: SUS 304 steel plate (nominal thickness 300 μm, TS300-300-03, manufactured by Iwata Seisakusho Co., Ltd.)

[0058] Next, in Examples 1 to 4, the following treatment films were formed in this order on the surface of the metal layer 1 facing the resin layer: (A) electromagnetic wave absorbing auxiliary film, (B) heat resistant film, (C) heat resistant film, (D) rust prevention film, and (E) weather resistant film. The treatment films were formed in order to bond the resin layer 1 to the surface of the metal layer 1. The thickness of the treatment films was submicron (10 -1 The formation time was adjusted appropriately so that the thickness would be about 1 μm or less. In addition, the surface of the metal layer 1 that comes into contact with air (the outermost surface) was treated with a heat-resistant film (C) and a rust-preventive film (D). After each treatment film was formed, the material was annealed at a material temperature of 200°C for a heating retention time of 1 hour.

[0059] (A) Electromagnetic wave absorption auxiliary film (Cu-Co-Ni alloy plating (roughened plating)) Solution composition: Copper 15.5g / L, Cobalt 7.0g / L, Nickel 9.3g / L pH: 2.3 Liquid temperature: 36.0℃ Current density: (Top side) 1st time: 21.3A / dm 2 , 2nd time: 29.9A / dm 2 , 3rd time: 56.8A / dm 2 (Bottom side) 1st time: 14.9A / dm 2 , 2nd time: 26.1A / dm 2 , 3rd time: 56.8A / dm 2 Coulombs: (Top surface) 1st time: 15.3As / dm 2 , 2nd time: 21.5As / dm 2 , 3rd time: 20.5As / dm 2 (Bottom surface) 1st time: 10.7As / dm 2 , 2nd time: 18.8As / dm 2 , 3rd time: 27.4 As / dm 2 (B) Heat-resistant film (Co-Ni alloy plating treatment) Solution composition: Nickel 12.5g / L, Cobalt 3.1g / L pH: 2.0 Liquid temperature: 50℃ Current density: (top) 17.5A / dm 2 , (bottom side) 19.3A / dm 2 Coulomb amount: (top surface) 6.3As / dm 2 , (bottom side) 6.9As / dm 2 (C) Heat-resistant film (Ni-Zn alloy plating treatment) Solution composition: Nickel 23.5g / L, zinc 4.5g / L pH: 3.7 Liquid temperature: 40℃ Current density: (top surface) 3.6A / dm 2 , (bottom side) 4.0A / dm 2 Coulomb amount: (top) 1.5 As / dm 2 , (bottom side) 1.6As / dm 2 (D) Anti-rust film (immersion chromate treatment) Solution composition: potassium dichromate 3.0g / L, zinc 0.33g / L pH: 3.65 Liquid temperature: 55℃ Processing time: 5 seconds (E) Weather-resistant film (silane coupling treatment) Silane coupling agent: N-(2-aminoethyl)-3-aminopropyltrimethoxysilane Silane coupling agent concentration: 1.2 vol% Processing temperature: 20℃ (room temperature) Processing time: 5 seconds

[0060] Next, in Examples 1 to 5, in order to laminate the metal layer and the resin layer to produce a laminate, an adhesive layer was formed between the metal layer and the resin layer via an adhesive (RU80 / H-5 (urethane adhesive for dry lamination, manufactured by Rock Paint Co., Ltd.)). The thickness of these adhesive layers was approximately 5 μm. As a result, sheet-like laminates were produced in Examples 1 to 5. A SUS304 steel plate was used in Comparative Example 1. A sheet of resin layer 1 was used in Reference Example 1.

[0061] [Characteristics evaluation] (unit weight) According to the method described above, the unit weights of Examples 1 to 5, Comparative Example 1, and Reference Example 1 were measured. The results are shown in Table 1.

[0062] (thermal diffusivity) The thermal diffusivities of Examples 1 to 5, Comparative Example 1, and Reference Example 1 were measured using a thermophysical property measuring device, Thermowave Analyzer TA35 Ultimate, according to the method described above. For Example 3 and other examples, the thermal diffusivity in the direction perpendicular to the stacking direction of the laminate (which means the thickness direction in Comparative Example 1 and Reference Example 1) was measured at five points near the center on the surface of each test specimen, and the arithmetic mean value is shown in Table 1. For Example 3, the thermal diffusivity in the direction perpendicular to the stacking direction of the laminate was measured at one point near the center on the surface of the test specimen, and the result is shown in Table 1.

[0063] (Evaluation of heat dissipation properties of sheet-shaped test specimens) The heat dissipation properties of Examples 1 to 5, Comparative Example 1 and Reference Example 1 were evaluated according to the following procedures (1) to (5). (1) Examples 1 to 5, Comparative Example 1, and Reference Example 1 were cut with scissors to obtain 5 cm × 5 cm test specimens. The surfaces of the test specimens were coated with blackbody spray (TA410KS, manufactured by TASCO, emissivity 0.94) to ensure a constant emissivity. (2) In the heat dissipation evaluation device 100 shown in Figure 1, a sheet-like specimen 110, a heat dissipation resin (1000 μm thick, TMS-E14N, manufactured by Takeuchi Industries Co., Ltd.) 120, a heating unit 130, and a low-dielectric resin (400 μm thick, GHPL-830NX type A, manufactured by Mitsubishi Gas Chemical Company, Inc.) 140 were arranged in this order from top to bottom. A heater (WALN-5, manufactured by Sakaguchi Electric Heating Co., Ltd.) 132 and a thermocouple 134 were connected to the heating unit 130. Current to the heater 132 was supplied from a constant-voltage power supply (model PMX18-2A, manufactured by KIKUSUI). Signal control to the power supply was performed using Wavy for PMX Free software, and current application and termination were controlled by creating and executing a sequence in the software. Temperature measurements from the thermocouple 134 were continuously recorded during the test on a data logger (model LR8431, manufactured by HIOKI). A thermal camera 150 (model C51.1, manufactured by FLIR) was installed 30 cm above the sheet-like test specimen 110. (3) A heat dissipation resin 120 of the same area was placed on the heating part 130, and Examples 1 to 5, Comparative Example 1, and Reference Example 1 were attached to it, and then a fixed voltage of 10 V was applied to the heater 132 for 20 seconds. After 20 seconds had elapsed, the voltage application was stopped. (4) Two minutes after the start of application, the temperature of the sheet-like specimen 110 was quickly measured using a thermo camera 150 placed above the sheet-like specimen 110. Table 1 shows the maximum temperature of the sheet-like specimen 110. When the maximum temperature of the heating section 130 was quickly measured using a thermocouple 134 immediately after application was stopped without a specimen placed on it, it was 65°C.

[0064] (Evaluation of heat dissipation of three-dimensional molded specimens) The heat dissipation properties were evaluated according to the following procedures (1) to (8) for Examples 1 to 5, Comparative Example 1, and Reference Example 1. In the following procedures (2) to (4), test specimens were produced by drawing at room temperature (approximately 22 to 26°C). (1) Examples 1 to 5, Comparative Example 1, and Reference Example 1 were cut with scissors to obtain polygonal specimens 210 as shown in Fig. 2. At this time, the length L of the diagonal line between vertex A and vertex B opposite vertex A of the polygonal specimen 210 was set to 72 mm. (2) The outer periphery of the polygonal test piece 210 was clamped between the die 220 and the holder 230 of the processing machine 200 shown in FIG. 3(A). (3) As shown in Fig. 3(B), the punch (tip surface size: 30 mm x 40 mm) 240 was moved vertically downward by 15 mm along the die 220 and holder 230 and pushed into the die hole. The clearance between the die 220 and punch 240 was set to 0.6 mm. (4) As shown in FIG. 3(C), the punch 240 was moved vertically upward and returned to its original position. This resulted in a drawn three-dimensional molded specimen 215. This three-dimensional molded specimen 215 had a bottomed shape. Note that, for Comparative Example 1, the bottom was damaged by the drawing process, so it was bent and processed so that the tip surface had dimensions of 30 mm x 40 mm and a height of 15 mm. The convex outer surface of the specimen was sprayed with blackbody spray (TA410KS, manufactured by TASCO, emissivity 0.94) to ensure a constant emissivity. (5) In the heat dissipation evaluation device 300 shown in FIG. 4, in order to clamp the outer periphery of the three-dimensional molded specimen 215, a heat dissipation resin (thickness 1000 μm, TMS-E14N, manufactured by Takeuchi Industries Co., Ltd.) 320, the outer periphery of the three-dimensional molded specimen 215, copper foil (thickness 18 μm, TPC, manufactured by JX Metals Corporation) 360, low-dielectric resin (thickness 400 μm, GHPL-830NX type A, manufactured by Mitsubishi Gas Chemical Company, Inc.) 340, and copper foil (thickness 18 μm, TPC, manufactured by JX Metals Corporation) 365 were arranged in this order from top to bottom. The heating unit 330 was placed on the low-dielectric resin 340 so that the center of gravity of the three-dimensional molded specimen 215 and the center of gravity of the heating unit 330 overlapped when viewed from above. A heater 332 and a thermocouple 334 were connected to the heating unit 330. Current to the heater was supplied from a constant voltage power supply (model PMX18-2A, manufactured by KIKUSUI), and signal control to the power supply was performed using Wavy for PMX Free software, with current application and termination being performed by creating a sequence control in the software. Temperature measurements from thermocouple 334 were constantly recorded during the test on a data logger (model LR8431, manufactured by HIOKI). A thermal camera 350 (model C51.1, manufactured by FLIR) was installed 30 cm above the three-dimensional molding test specimen 215. (6) A voltage fixed at 10 V was applied to the heater 332 for 70 seconds. After 70 seconds had elapsed, the application of voltage was stopped. (7) After the application of the voltage was stopped, the temperature of the heating part 330 was immediately measured by the thermocouple 334. As a result, the temperature was 370°C in all of Examples 1 to 5, Comparative Example 1 and Reference Example 1. (8) Furthermore, after 2 minutes had elapsed since the start of application of the voltage, the temperature of the three-dimensional molding test piece 215 was quickly measured using a thermal camera 350 placed above the three-dimensional molding test piece 215. Table 1 shows the maximum temperature of the three-dimensional molding test piece 215.

[0065] (Heat dissipation judgment) In the heat dissipation evaluation of the sheet-like specimen and the three-dimensional molded specimen, the specimens were measured two minutes after the start of application of the voltage. If the maximum temperature of both specimens was 40°C or less, it was marked with a "◎", if it was above 40°C and below 45°C, it was marked with a "○", and if it was anything other than that, it was marked with a "△", as shown in Table 1. If it was marked with a "◎" or "○", it was judged that the heat dissipation was good, while if it was marked with a "△", it was judged that the heat dissipation was not good.

[0066] (Shielding properties) The shielding properties of each sheet were measured for Examples 1 to 5, Comparative Example 1, and Reference Example 1. First, the outer periphery of each test specimen was fixed with tape to prevent misalignment during measurement. The magnetic field shielding properties of each material were evaluated at room temperature (approximately 22 to 26°C) using the KEC method at a frequency of 100 kHz using a magnetic field measuring jig of a KEC method shielding effectiveness measuring device (manufactured by Techno Science, JSE-KEC), a network analyzer (manufactured by Keysight Technologies, E5080), and an amplifier (manufactured by Anritsu, MH648A). The results are shown in Table 1.

[0067] [Table 1]

[0068] (Considerations based on examples) The laminates in Examples 1 to 5 were laminates having at least one metal layer and at least one resin layer, and the unit weight of the laminates was 2.0 kg / m 2 and the thermal diffusivity in the direction perpendicular to the stacking direction of the laminate is 10 × 10 -6 m 2 / s or more, the laminates in Examples 1 to 5 had good heat dissipation properties while achieving weight reduction. Furthermore, the laminates in Examples 1 to 5 had a shielding effect of 10 dB or more at 100 kHz, and also had good shielding properties. According to Table 1, Example 4 had slightly poorer heat dissipation than Example 3, which had a slightly poorer thermal diffusivity. The reason for this is presumably that the heat dissipation was saturated when the thermal diffusivity reached a certain value or more.

[0069] On the other hand, the laminate of Comparative Example 1 was composed of only a metal layer, and therefore had a unit weight 2.4 times or more larger than that of the laminates of Examples 1 to 5. [Explanation of symbols]

[0070] 100, 300 Heat dissipation evaluation device 110 Sheet-shaped specimen 120, 320 heat dissipation resin 130, 330 heating section 132, 332 heater 134, 334 thermocouple 140, 340 Low dielectric resin 150, 350 thermal camera 200 processing machines 210 Polygonal specimen 215 Three-dimensional molding test specimen 220 Die 230 Holder 240 punch 360, 365 copper foil A and B vertices L Diagonal length

Claims

1. A laminate having at least one metal layer and at least one resin layer, The unit weight of the laminate is 2.0 kg / m 2 and the thermal diffusivity of the laminate in the direction perpendicular to the lamination direction is 10×10 -6 m 2 / s or more, A laminate in which a treated film of an alloy containing nickel is interposed between the at least one metal layer and the at least one resin layer.

2. The thermal diffusivity in the direction perpendicular to the lamination direction of the resin layer is 0.05×10 -6 ~0.70 x 10 -6 m 2 The laminate according to claim 1, wherein the thickness is 1 / s.

3. The laminate according to claim 1 , wherein the resin layer contains a magnetic metal material.

4. The laminate according to claim 1 or 2, wherein the metal layer contains at least one selected from copper, a copper alloy, aluminum, and an aluminum alloy.

5. 3. The laminate according to claim 1, wherein a treated film of an alloy containing copper is interposed between the at least one metal layer and the at least one resin layer.

6. The laminate according to claim 1 or 2, further comprising a treatment film containing cobalt or nickel on at least one surface of the metal layer.

7. A heat dissipation member comprising the laminate according to claim 1 or 2.

8. A method for manufacturing a heat dissipation member, comprising the step of manufacturing a heat dissipation member using the laminate according to claim 1 or 2.

9. A heat dissipation housing comprising the laminate according to claim 1 or 2.

10. A method for manufacturing a heat dissipating enclosure, comprising the step of manufacturing a heat dissipating enclosure using the laminate according to claim 1 or 2.

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