JP5368396B2 - Resin-coated metal material and electronic device parts using the metal material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin-coated metallic material having excellent thermal conductivity in the plane direction and corrosion resistance. <P>SOLUTION: In the resin-coated metallic material, a resin film which includes 35-65 mass% of Al particles having a flat shape and 10 &mu;m or less of average particle length and has film thickness of 3.0-8.0 &mu;m is provided on at least one side of a metallic base material. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a resin-coated metal material excellent in surface direction thermal conductivity and corrosion resistance, and an electronic device component using the resin-coated metal material.

  With increasing performance and miniaturization of electronic devices, research on heat radiating members that dissipate heat generated from heat sources inside the electronic devices has been actively conducted. Of these, heat dissipation members that are in local contact with heat sources, such as the back chassis of flat-screen televisions, can quickly diffuse the generated heat over a large area, that is, the thermal conductivity in the surface direction of the heat dissipation member. It is required to be excellent. This is because if the thermal conductivity in the plane direction is low, a temperature gradient occurs in the plane direction, resulting in variations in the in-plane temperature, causing problems such as uneven color of the light emitting surface and cracking of the glass substrate.

  In particular, when the heat radiating member is made of a metal plate such as a steel plate and the heat source is in contact with the metal plate, the heat conductivity in the surface direction is increased instead of the heat conductivity in the thickness direction of the metal plate. Is extremely important. There are two possible paths for heat transfer from the heat source to the outside of the metal plate: the thickness direction and the surface direction, but with a thin metal plate such as a steel plate, improving the thermal conductivity in the thickness direction This is because although the maximum temperature is lowered, the temperature gradient in the surface direction is hardly lowered, and the effect of reducing the temperature gradient in the surface direction can be expected only after the thermal conductivity in the surface direction is improved.

  However, much research on the heat radiating member focuses on improving the thermal conductivity in the thickness direction of the heat radiating member, and little attention is paid to the thermal conductivity in the surface direction of the heat radiating member. For example, Patent Document 1 discloses a surface-treated metal plate that has a heat-absorbing film containing a heat-conducting material having a predetermined heat conductivity on the surface of the metal plate and has improved heat emissivity and heat absorption rate. Yes. The technique of this document is such that the average particle diameter D of the heat conductive material is 0.8 t ≦ D ≦ 1.2 t with respect to the film thickness t of the film, and the metal sheet is projected by protruding the heat conductive material from the film. This increases the thermal conductivity in the thickness direction.

  On the other hand, in Patent Document 2, a resin film containing a heat-dissipating additive in addition to a predetermined amount of magnetic powder is provided on the surface of a metal plate, and the resin has improved heat dissipation as well as electromagnetic wave absorption and workability. A coated metal plate is disclosed, and scaly aluminum (hereinafter referred to as Al) flakes and the like are exemplified as the heat-dissipating additive. However, the technique of the document is not made by focusing on the heat conduction in the surface direction.

  In addition, since electronic devices are used in various environments (temperature, humidity, etc.), heat dissipation members used in electronic devices are also required to have excellent corrosion resistance in addition to thermal conductivity in the surface direction.

JP 2009-286091 A JP 2005-271572 A

  In the present invention, in view of the circumstances as described above, an object of the present invention is to provide a resin-coated metal material having excellent surface direction thermal conductivity and corrosion resistance.

  The resin-coated metal material of the present invention capable of solving the above-mentioned problems includes 35 to 65 mass% of Al particles having a flat shape and an average particle length of 10 μm or less on at least one side of the metal substrate, and a film thickness of 3.0. It has a resin film of ˜8.0 μm.

  In the present invention, the Al particles are treated with stearic acid, or the resin film is provided on one side of a metal base, and the other side includes a heat-dissipating additive, and the infrared emissivity. It is a preferred embodiment that has a resin film of 0.7% or more.

  The present invention also includes an electronic device component using the resin-coated metal material.

  The resin-coated metal material of the present invention has a resin film with an appropriately adjusted film thickness on the surface of the metal material, and the resin film contains a predetermined amount of flat Al particles having a predetermined particle length. It was possible to provide a resin-coated metal material excellent in corrosion resistance as well as thermal conductivity in the direction.

It is a figure for demonstrating the component of the experimental apparatus for evaluating heat dissipation. It is a schematic explanatory drawing which shows the structure of the experimental apparatus for evaluating heat dissipation.

  Among the heat radiating members for electronic devices, the present inventors not only require high thermal conductivity in the surface direction because the heat source is locally in contact with the heat radiating member, but also because the usage environment is diverse. In order to provide a resin-coated metal material suitable as a material for a heat dissipation member that also requires high corrosion resistance, studies have been made repeatedly. As a result, the desired high surface direction thermal conductivity and corrosion resistance cannot be obtained simply by using scaly Al flakes, etc., and the particle length and content, and the film thickness of the resin film are appropriately controlled. As a result, the present invention was completed.

  That is, the resin-coated metal material of the present invention includes 35 to 65% by mass of Al particles having a flat shape and an average particle length of 10 μm or less on at least one side of the metal substrate, and a film thickness of 3.0 to 8.0 μm. It has a resin film. Hereinafter, the resin-coated metal plate of the present invention will be described in detail.

(Metal base material)
The shape of the metal substrate used in the present invention is not particularly limited and typically includes a metal plate, but other deformed materials can also be used.

  Moreover, the kind of metal base material is not specifically limited, The thing normally used for the housing | casing of an electronic device component, etc. can be used. Taking a metal plate as an example, typically, a steel plate is exemplified, and a cold rolled steel plate, a hot rolled steel plate, a stainless steel plate and the like are exemplified. In addition, various types of plated steel sheets such as electrogalvanized steel sheets (EG), hot dip galvanized steel sheets (GI), alloyed hot dip galvanized steel sheets (GA), Al-Zn plated steel sheets, and Cu based plated steel sheets; A steel plate subjected to surface treatment such as chromate treatment or phosphate treatment; a steel plate subjected to non-chromate treatment may be used. Or a nonferrous metal plate is also applicable.

  The thickness of the metal substrate used in the present invention is not particularly limited, but the thickness is 0.4 mm or more (more preferably 0.6 mm or more, more preferably 0.7 mm or more), 1.6 mm or less (preferably 1. 2 mm or less, more preferably 1.0 mm or less). By producing the resin-coated metal material of the present invention using a metal substrate having a thickness within the above range, a dramatic increase in the amount of heat transfer due to an improvement in the thermal conductivity in the surface direction can be expected.

(Resin film containing Al particles)
The resin film containing Al particles constituting the resin-coated metal material of the present invention (hereinafter sometimes referred to as “thermal conductive film”) has a film thickness of 3.0 μm or more (preferably 4.0 μm or more). , 8.0 μm or less (preferably 7.0 μm or less). When the film thickness of the heat conductive film is less than 3.0 μm, the barrier effect by the resin is lowered, and therefore, the effect of improving the corrosion resistance of the resin-coated metal material by providing the resin film becomes difficult. On the other hand, if the film thickness of the thermal conductive film exceeds 8.0 μm, the insulation by the resin increases, so the effect of improving the surface thermal conductivity of the resin-coated metal material by including Al particles in the resin film Becomes difficult to be demonstrated. The heat conductive film may be provided directly on the metal substrate or may be provided with another film interposed.

  The resin (base resin) constituting the heat conductive film is not particularly limited as long as the effects of the present invention (improvement in surface direction heat conductivity and corrosion resistance) are not impaired, and may be appropriate depending on the use of the resin-coated metal material. What is necessary is just to select resin. For example, when the resin-coated metal material of the present invention is used for a casing of an electronic device part, good workability is also required, and therefore, a polyester-based resin, an epoxy-based resin, a blend thereof, a modified resin, and the like are preferable. It is mentioned as a thing.

(Al particles)
In the present invention, Al particles are used as the heat conductive particles to be contained in the resin film. Examples of the thermally conductive particles include Ag (thermal conductivity 429 W / m · K) and Cu (thermal conductivity 401 W / m · K) in addition to Al, but Al (thermal conductivity 200 W / m) from the viewpoint of corrosion resistance. -K) is most preferred.

  The Al particles used in the present invention are flat. Presumably, by incorporating flat Al particles having high thermal conductivity into the resin film, the Al particles in the film are inclined with respect to the thickness direction, and the Al particles come into contact with each other to improve the surface thermal conductivity of the film. Is done. In addition, when a spherical metal filler is used as the heat conductive particles, the fillers hardly come into contact with each other, so that the effect of improving the surface direction thermal conductivity of the coating cannot be expected so much.

  The average particle length of the Al particles used in the present invention is 10 μm or less (more preferably 8 μm or less, more preferably 6 μm or less). If the particle length of the Al particles is too large with respect to the film thickness of the heat conductive film, the resin film is difficult to become a continuous film when the thickness of the heat conductive film is reduced, and the barrier effect by the resin is reduced. It may not be possible to ensure excellent corrosion resistance. The lower limit of the average particle length of the Al particles is preferably 1 μm (more preferably 3 μm, still more preferably 5 μm).

  The average particle length of the Al particles is, for example, a value measured by a microscope or a volume-based average value of particle diameters obtained by measurement by a laser diffraction / scattering method (microtrack method). In addition, when using commercially available Al particles, the average particle length provided by the manufacturer may be referred to.

  The surface of the Al particles used in the present invention is preferably treated with stearic acid. Such Al particles are commercially available as leafing types. Al particles whose surface is not treated with stearic acid (non-leafing type) are uniformly dispersed in the thermally conductive film, whereas Al particles whose surface is treated with stearic acid (leafing type) are heated. Since there is a tendency to float on the surface layer of the conductive film, it is possible to prevent the heat conductive film from being wrinkled and to improve the wrinkle resistance of the resin-coated metal material.

  The content of Al particles in the thermally conductive film is 35% by mass or more (preferably 40% by mass or more, more preferably 45% by mass or more), 65% by mass or less (preferably 60% by mass or less, more preferably 55% by mass). Mass% or less). When the content rate of Al particle | grains is less than 35 mass%, Al particle | grains become difficult to contact and the surface direction thermal conductivity of a resin coating metal material may not fully improve. When the content of Al particles exceeds 65% by mass, the resin film is less likely to be a continuous film in the region of the film thickness of 3.0 to 8.0 μm where the thermal conductivity is improved by the heat conductive film. Since the barrier effect is lowered, the corrosion resistance may not be sufficiently improved.

(Additive ingredients)
In addition to the Al particles and the resin, the thermally conductive film may include an additive component that is usually added to the resin film. Examples of the additive component include rust preventive pigments, antistatic agents, conductive particles, and weather resistance improvers. The said additive component can be contained in a heat conductive film in the range which does not impair the effect | action of this invention.

(Resin film containing heat dissipation additive)
In the resin-coated metal material of the present invention, the heat conductive film only needs to be formed on at least one side (heat source side) of the metal substrate, but may be provided on both surfaces of the metal substrate. Thereby, the heat from the heat source can be diffused and transferred more rapidly in the surface direction of the metal substrate.

  In addition, the resin-coated metal material of the present invention has the above-mentioned heat conductive film on one side of the metal substrate, and a resin film containing a heat-dissipating additive (hereinafter referred to as heat-dissipating film) on the other side. You may do it. Thereby, the heat diffused in the surface direction by the heat conductive film can be quickly removed (heat radiation) from the resin-coated metal material. The heat dissipating film may be provided directly on the metal substrate or may be provided with another film interposed.

The heat dissipating film can be formed by adding a heat dissipating additive to the resin (base resin) constituting the film. The resin (base resin) constituting the heat dissipating film is not particularly limited, and the resins listed as resins that can be used to form the heat conductive film can be used. The heat dissipation additive is not particularly limited, and a known heat dissipation additive may be used. For example, in addition to carbon black, oxides such as Co, Ni, Cu, Mn, Ag, and Sn, sulfides, carbides, TiO ₂ , ceramics, iron oxide, aluminum oxide, barium sulfate, silicon oxide, etc. It is done.

  The average particle size of the heat dissipating additive is preferably 10 nm or more (more preferably 15 nm), and preferably 35 nm or less (more preferably 30 nm or less). The average particle diameter of the heat-dissipating additive can be measured, for example, by a laser diffraction / scattering method (microtrack method). In addition, when using a commercially available heat-dissipating additive, the particle size provided by the manufacturer may be referred to.

  The film thickness of the heat dissipating film is preferably 5 μm or more (more preferably 8 μm or more), and preferably 20 μm or less (more preferably 15 μm or less). Further, the content of the heat dissipating additive in the heat dissipating film is preferably 5% by mass or more (more preferably 8% by mass or more), and preferably 20% by mass or less (more preferably 15% by mass or less).

  The infrared emissivity of the heat dissipating film is preferably 0.7% or more (more preferably 0.75% or more). When the infrared emissivity is less than 0.7%, the resin-coated metal material of the present invention may not exhibit sufficient heat dissipation. A method for calculating the infrared emissivity will be described later.

(Clear film)
The resin-coated metal material of the present invention may further have another film on the heat conductive film and / or the heat dissipating film. For example, a known clear film may be provided on the heat conductive film and / or the heat dissipating film for the purpose of improving scratch resistance and fingerprint resistance.

(Method of forming heat conductive film and heat dissipation film)
The heat conductive film can be formed by a conventionally known method. For example, a paint in which the above base resin and Al particles, and other additives as necessary are dissolved or dispersed in a solvent, can be formed by a known coating method. It can form by apply | coating to the surface of a metal base material, drying, or heat-baking.

  The heat dissipating film can also be formed by a conventionally known method. For example, a paint in which the above base resin and heat dissipating additive are dissolved or dispersed in a solvent is applied to the surface of the metal substrate by a known coating method. It can be formed by drying or heating and baking.

  The coating method of the paint is not particularly limited. For example, the surface of a metal substrate that has been subjected to a pretreatment (for example, phosphate treatment, chromate treatment, etc.) after cleaning the surface is optionally applied to a roll coater method, Examples thereof include a method in which a paint is applied using a bar coater method, a spray method, a curtain flow coater method, etc., and is dried by passing through a hot air drying furnace, or is baked and cured.

(Electronic equipment parts)
Since the resin-coated metal material of the present invention is excellent in surface direction thermal conductivity and corrosion resistance, it can be suitably used as a heat radiating component for electronic equipment. Examples of the electronic device component include a heat sink, a back chassis such as a thin television, and a metal casing (casing) that houses an electronic device component incorporating a heat source.

  Hereinafter, the present invention will be described in detail based on examples. However, the following examples are not intended to limit the present invention, and all modifications made without departing from the spirit of the preceding and following descriptions are included in the technical scope of the present invention.

(Preparation of thermal conductive coating forming paint)
Polyester resin (Toyobo Co., Ltd., Byron (registered trademark) 290, Tg 72 ° C., molecular weight (Mn) 22 × 10 ³ (all catalog values)) and melamine cross-linking agent (Sumitomo Chemical Co., Ltd., Sumimar (registered trademark) M- 40ST, solid content 80% by mass) at a ratio of 100: 20 (dry mass ratio) to form a matrix resin, and the following thermally conductive particles (various flat Al particle-containing pastes or various flat copper particles) are added. , Diluted with thinner (manufactured by Daishin Chemical Co., Ltd., thin plate integrated A thinner, xylene 50 mass% + cyclohexanone 50 mass% mixed thinner) to adjust the viscosity appropriately, and stirred with a dispers stirrer at 3000 rpm × 5 minutes, A paint for forming a conductive film was prepared. Table 1 shows the contents of the flat Al particles and the flat copper particles in the thermally conductive film.

<Additives>
Flat Al particle-containing paste (all manufactured by Asahi Kasei Chemicals)
・ 13H average particle length 6μm (leafing)
・ FD-5060 average particle length 6μm (non-leafing)
・ 18TH average particle length 8μm (leafing)
・ 8LN-S average particle length 8μm (non-leafing)
・ 66NL-S average particle length 10μm (non-leafing)
・ 8 Average particle length 11μm (leafing)
・ BS-240 average particle length 16μm (non-leafing)
・ 2 Average particle length 17μm (leafing)
Flat copper particles ・ 1400YP Average particle length 6.9μm (Mitsui Metals)
・ 2L3N average particle length 9.9μm (Fukuda Metal Foil Industry)

(Preparation of heat-dissipating film-forming paint)
Polyester resin (Toyobo Co., Ltd., Byron (registered trademark) 290, Tg 72 ° C., molecular weight (Mn) 22 × 10 ³ (all catalog values)) and melamine cross-linking agent (Sumitomo Chemical Co., Ltd., Sumimar (registered trademark) M- 40ST, solid content 80% by mass) at a ratio of 100: 20 (dry mass ratio) to form a matrix resin, and carbon black (Mitsubishi Chemical Corporation, Mitsubishi Carbon Black MA100, average particle size 25 nm) as a heat-dissipating additive. It added so that it might become 10% of content rate. The resulting mixture is diluted with a xylene / cyclohexanone mixed solvent (xylene: cyclohexanone = 1: 1) so that the viscosity is about 30 to 100 seconds (Ford Cup No. 4), and 3000 rpm × 5 with a disper stirrer. The mixture was stirred for a minute to produce a heat-dissipating film-forming paint.

(Experiment 1)
As the metal substrate, an A4 size electrogalvanized steel sheet with a plate thickness of 0.8 mm (plating adhesion amount: 19 g / m ² ) was used, and the metal substrate 1 was obtained.

(Experimental Examples 2-46)
A ground treatment solution (manufactured by Nihon Parkerizing, CTE-213A) was attached to one surface of the metal substrate 1 so as to have an adhesion amount of 100 mg / m ^2, and the metal substrate was subjected to the ground treatment. Next, a coating material for forming a heat conductive film is applied on the surface to be treated with a bar coater, and baked for 120 seconds at a maximum attained temperature (PMT) of 220 ° C. Resin-coated metal plates 2 to 46 having a film were obtained.

  The characteristics of the metal substrate 1 obtained in the experimental example 1 and the resin-coated metal plates 2 to 46 obtained in the experimental examples 2 to 46 were evaluated by the following methods. The evaluation results are shown in Table 1 below.

(Thermal conductivity)
The thermal conductivity in the surface direction of the metal substrate 1 and the resin-coated metal plates 2 to 46 was calculated from the following calculation formula and evaluated.
Thermal conductivity (W / m · K) = density (10 ³ kg / m ³ ) × specific heat (10 ³ J / kg · K) × thermal diffusivity (10 ⁻⁶ m ² / sec)
(Evaluation criteria)
A: Thermal conductivity of metal substrate 1 +2.0 W / m · K or more ○: Thermal conductivity of metal substrate 1 +0.1 W / m · K or more and less than 2.0 W / m · K ×: Metal substrate 1 Note that the density, specific heat, and thermal diffusivity for calculating the thermal conductivity were measured as follows.

<Density>
A 25 mm × 25 mm test sample was cut out from the metal substrate 1 and the resin-coated metal plates 2 to 46 and measured at room temperature by an underwater substitution method.

<Specific heat>
A test sample of about 50 to 60 mg is cut out from the metal substrate 1 and the resin-coated metal plate 2 to 46, and using a differential scanning calorimeter (DSC220C, manufactured by Seiko Instruments Inc.), the specific heat at room temperature (25 ° C.) in an argon atmosphere. Was measured.

<Thermal diffusivity>
A 25 mm × 25 mm test sample was cut out from the metal substrate 1 and the resin-coated metal plates 2 to 46, and carbon spray was sprayed on both sides to uniformly blacken. Next, using a thermal constant measuring apparatus (manufactured by ULVAC-RIKO, TC-7000), at a room temperature (25 ° C.) and in a vacuum, on the surface on which the heat conductive film is not formed (blackened steel plate surface) Irradiation with an infrared laser (transmitting wavelength: 1.06 μm), the back surface (the other surface of the metal substrate 1 or the surface on which the heat conductive film is formed) at a location 5 mm away from the laser irradiation position in the surface direction ) Was measured with a thermocouple, a time t when the temperature was half the maximum value was calculated, and calculated based on the following equation.
Thermal diffusivity α (m ² / sec) = K / t
(In the formula, K represents an apparatus constant based on tantalum (25 × 10 ⁻⁶ m ² / sec), which is a known thermal diffusivity, and is determined by αt _tan = K. T _tan is the maximum temperature during tantalum measurement. (It represents the time when it is half the value.)

(Corrosion resistance)
A test sample (5 cm × 12 cm) is cut out from the resin-coated metal plates 7 to 46, subjected to a salt spray test in accordance with JIS Z 2371, and white rust of the test sample (heat conductive film forming surface) after the 120-hour test. The incidence was evaluated.
(Evaluation criteria)
◎: 5% or less ○: More than 5% 40% or less ×: More than 40%

(Scratch resistance)
Test samples were cut out from the resin-coated metal plates 7 to 36, and in accordance with JIS K 5600, a pencil hardness test was performed on the thermally conductive coating surface for evaluation.
(Evaluation criteria)
A: H or more B: F to HB
X: Less than HB

(Experimental example 47)
A ground treatment liquid (manufactured by Nihon Parkerizing Co., Ltd., CTE-213A) is attached to one surface (back surface) of the metal substrate 1 of Experimental Example 1 so as to have an adhesion amount of 100 mg / m ^2, and the metal substrate is ground-treated. Went. Next, a paint for forming a heat-dissipating film was applied to the ground surface with a bar coater, and baked for 120 seconds at a maximum temperature (PMT) of 220 ° C. to have a heat-dissipating film having a thickness of 10 μm on one side (back surface) ( A resin-coated metal plate 47 having no thermal conductive film on the other side (surface) was obtained.

(Experimental Examples 48-53)
On the other side (rear surface) of the resin-coated metal plate produced in Experimental Examples 5, 6, 8, 11, 17, and 26, a ground treatment and a heat dissipation film were formed in the same manner as in Experimental Example 47, Resin-coated metal plates 48 to 53 having a heat conductive film with a thickness of 0.8 to 5.2 μm on the surface and a heat dissipating film with a thickness of 10 μm on the back surface were obtained.

(Experimental example 54)
As the metal substrate, a hot-dip galvanized steel sheet (A4 size, plate thickness 0.8 mm) having the plating adhesion amount shown in Table 2 was used as the metal substrate 2.

(Experimental example 55)
In Experimental Example 47, a heat-radiating film having a thickness of 10 μm is provided on one side (back surface) in the same manner as in Experimental Example 47 except that the metal base material 2 is used instead of the metal base material 1 (the other one surface (surface ), A resin-coated metal plate 55 having no thermal conductive film was obtained.

(Experimental Examples 56-61)
One surface (surface) is the same as Experimental Examples 5, 6, 8, 11, 17, and 26 except that the metallic substrate 2 of Experimental Example 54 is used instead of the metallic substrate 1 of Experimental Example 1. A resin-coated metal plate having a thermally conductive film with a thickness of 0.8 to 5.2 μm was obtained.

  Next, on the other surface (rear surface) of the obtained resin-coated metal plate, a base treatment and a heat-dissipating film were formed in the same manner as in Experimental Example 47, and a thickness of 0.8 to 5.2 μm was formed on the surface. Resin-coated metal plates 56 to 61 having a heat conductive film and a heat-radiating film having a thickness of 10 μm on the back surface were obtained.

(Infrared emissivity)
The infrared emissivity is measured on the back side (one side of the metal bases 1 and 2 or the heat-dissipating film side) of the metal bases 1 and 2 and the resin-coated metal plates 47 to 61 (samples) using the following apparatus. The spectral radiant intensity (measured value) in the infrared wavelength region (4.5 to 15.4 μm) was measured and obtained.
Apparatus: “JIR-5500 type Fourier transform infrared spectrophotometer” manufactured by JEOL Ltd. and radiation measurement unit “IRR-200”
Measurement wavelength range: 4.5 to 15.4 μm
Measurement temperature: Heating temperature of sample set to 100 ° C. Number of integrations: 200 times Resolution: 16 cm ⁻¹

  In addition, since the said actual measurement value is measured as a numerical value to which the background radiation intensity and the instrument function are added / added, for the purpose of correcting these, an emissivity measurement program [emissivity measurement program manufactured by JEOL Ltd.] ] To calculate the integral emissivity. Details of the calculation method are as follows.

Where
ε (λ): Spectral emissivity of sample at wavelength λ (%)
E (T): Integrated emissivity (%) of sample at temperature T (° C.)
M (λ, T): Spectral radiant intensity of sample at wavelength λ and temperature T (° C.) (actual measured value)
A (λ): Instrument function K _FB (λ): Spectral radiant intensity K _TB (λ, T _TB ) of fixed background at wavelength λ (background that does not vary with the sample): Wavelength λ, at temperature T _TB (° C.) Spectral radiant intensity K _B (λ, T) of trapped black body: Spectral radiant intensity of black body at wavelength λ and temperature T (° C.) (calculated from theoretical formula of blank)
λ ₁ , λ ₂ : Means the range of wavelengths to integrate.

Here, A (λ) (apparatus function) and K _FB (λ) (fixed background spectral radiant intensity) are measured values of spectral radiant intensity of two blackbody furnaces (80 ° C., 160 ° C.). , And the spectral radiant intensity of the black body in the temperature range (calculated value from the theoretical formula of the blank).

Where
M _{160 ° C.} (λ, 160 ° C.): Spectral radiation intensity of 160 ° C. blackbody furnace at wavelength λ (actual measured value)
M _{80 ° C.} (λ, 80 ° C.): Spectral radiation intensity of 80 ° C. blackbody furnace at wavelength λ (actual measured value)
K _{160 ° C.} (λ, 160 ° C.): spectral radiant intensity of a black body furnace at 160 ° C. at a wavelength λ (calculated from the theoretical formula of the blank)
K _{80 ° C.} (λ, 80 ° C.): Means the spectral radiant intensity (calculated from the theoretical formula of the blank) of the black body furnace at 80 ° C. at the wavelength λ.

In calculating the integral emissivity E (T = 100 ° C.), K _TB (λ, T _TB ) is taken into consideration when a trapped black body cooled with water is placed around the sample. Because. Due to the installation of the trap black body, variable background radiation (meaning background radiation that varies depending on the sample. Since the radiation from around the sample is reflected by the sample surface, the measured value of the spectral radiant intensity of the sample is Spectral radiation intensity (which appears as a numerical value with background radiation added) can be controlled low. The above trap black body uses a pseudo black body with an emissivity of 0.96, and K _TB [(λ, T _TB ): spectral radiant intensity of the trap black body at wavelength λ and temperature T _TB (° C.). ] Is calculated as follows.
K _TB (λ, T _TB ) = 0.96 × K _B (λ, T _TB )
In the formula, K _B (λ, T _TB ) means the spectral radiant intensity of a black body at a wavelength λ and a temperature T _TB (° C.).

(Thermal diffusion)
A test sample of 150 mm × 250 mm was cut out from the metal substrates 1 and 2 and the resin-coated metal plates 47 to 61 (samples), and thermal diffusivity was evaluated according to the following method.

  As shown in FIG. 1 (FIG. 1 (a) is a bird's-eye view, FIG. 1 (b) is a side view, and FIG. 1 (c) is a front view). A heater 2 (56 mm × 96 mm) was fixed to the center of the back surface of the sample 1 (one surface of the metal base 1 or 2 or the surface of the heat conductive film), and the periphery was covered with the heat insulating material 3. Then, three thermocouples 4a, 4b, and 4c were arranged on the back side of the test sample 1 (the right side of FIG. 1B; the other side of the metal bases 1 and 2 or the heat dissipating film surface). At room temperature (25 ° C), the maximum temperature is evaluated with the thermocouple 4a placed at the center of the sample, the minimum temperature is evaluated with either the thermocouple 4b or 4c, and the difference between the maximum temperature and the minimum temperature = in-plane temperature is measured. did.

  A plurality (8 in FIG. 2) of members 5 (components) shown in FIG. 1 are arranged to configure an experimental apparatus as shown in FIG. 2, and the thermal diffusivity of each sample is evaluated. The heat source was an electric heater, and the voltage from the power source (shown as “100 V power source” in FIG. 2) was adjusted by the power stabilizer and the output regulator, thereby adjusting the heat output of the heater.

  After waiting about 5 hours from the start of heating until the measured value of the thermocouple was stabilized by such an experimental device, the temperature measurement data was captured by the thermometer measurement data logger and displayed on the display device 6. The experimental conditions at this time were room temperature and the heater output was 20 W.

  The results of the temperature measured by the above experiment are shown in Table 2 below together with the sample specifications.

Claims (4)

  A resin coating characterized by having a resin film having a thickness of 3.0 to 8.0 μm on at least one side of a metal substrate containing 35 to 65 mass% of Al particles having an average particle length of 10 μm or less. Metal material.   The resin-coated metal material according to claim 1, wherein the Al particles are treated with stearic acid.   The resin according to claim 1 or 2, wherein the resin film is provided on one side of the metal substrate, and the other one side includes a resin film having a heat radiation additive and an infrared emissivity of 0.7% or more. Painted metal material.   An electronic device component using the resin-coated metal material according to any one of claims 1 to 3.

Images