WO2014175344A1 - Aqueous coating material, heat-dissipating member, metallic part, and electronic device - Google Patents

Abstract

According to the present invention, an aqueous coating material can be produced, which is easy to handle and enables the formation of a film having excellent heat-dissipating performance, heat resistance and adhesiveness. The aqueous coating material according to the present invention comprises: polyurethane resin microparticles; a first filler which comprises an orthorhombic silicate mineral capable of releasing a far-infrared ray; and water in which the polyurethane resin microparticles and the first filler are dispersed.

Description

Water-based paint, heat dissipation member, metal parts, electronic equipment

The present invention relates to a water-based paint. In particular, the present invention relates to a water-based paint capable of forming a film having heat dissipation properties.

2. Description of the Related Art A heat sink is known as a member that is attached to a mechanical / electrical part that generates heat and aims to lower the temperature by radiating heat. In many cases, heat sinks are mainly made of metal such as aluminum or copper, which easily conducts heat.
In an aluminum heat sink, a method of anodizing the surface by anodizing is known as a method for further enhancing the heat dissipation effect. However, alumite processing needs to change a bathtub for every process, such as a degreasing process, water washing, and an anodizing process. In addition, many fine pores exist in the film obtained by the anodic oxidation treatment, and these fine pores cause cracks and corrosion. Therefore, a sealing treatment is required as a subsequent process. Thus, anodizing has a problem that many processes are required and productivity is poor.

Patent Document 1 discloses an aqueous composition and a coating composition containing an alkali metal silicate and water and a specific metal compound as a liquid phase for the purpose of lowering the temperature by heat dissipation. It is disclosed.
However, in addition to high heat dissipation and high productivity, a member for heat dissipation is required to have close contact with a heat source and heat resistance in order to improve heat transfer.

JP 2004-002813 A

Therefore, an object of the present invention is to provide a water-based paint that is easy to handle and can form a film excellent in heat dissipation, heat resistance, and adhesion.

The present inventors have intensively studied to solve the above problems. As a result, it has been found that an aqueous dispersion (dispersion liquid) containing polyurethane resin fine particles and orthorhombic silicate mineral can be an aqueous paint capable of forming a film having high heat dissipation properties. Was completed.

The water-based paint according to the first aspect of the present invention includes polyurethane resin fine particles; a first filler formed of an orthorhombic silicate mineral that emits far infrared rays; the polyurethane resin fine particles and the first The filler contains dispersed water.
The “silicate mineral” may be either natural or artificial, and includes aluminosilicate minerals and silicate compounds other than minerals.
If comprised in this way, since it is a water-based paint, handling and conveyance of application | coating etc. become easy. Furthermore, since it is a paint based on polyurethane, it is possible to form a highly ductile film having excellent adhesion to metal surfaces and heat resistance compared to paints based on acrylic or epoxy. Furthermore, since it contains an orthorhombic silicate mineral, the formed film can convert heat into far infrared rays and release it, and has high heat dissipation.

The water-based paint according to the second aspect of the present invention is the water-based paint according to the first aspect of the present invention, wherein the material constituting the polyurethane resin fine particles is polycarbonate polyurethane, polyester polyurethane, aliphatic polyurethane, fatty acid-modified polyurethane. , At least one selected from the group consisting of aromatic polyurethane and polyether polyurethane. “Polycarbonate polyurethane” refers to a polyurethane resin having a polycarbonate skeleton in the main chain. “Polyester polyurethane” refers to a polyurethane resin having a polyester skeleton in the main chain. “Aliphatic polyurethane” refers to a polyurethane resin having an aliphatic chain in the main chain. “Fatty acid-modified polyurethane” refers to a polyurethane resin having a modified fatty acid skeleton in the main chain. “Aromatic polyurethane” refers to a polyurethane resin having an aromatic group in the main chain. “Polyether polyurethane” refers to a polyurethane resin having a polyether skeleton in the main chain.
If comprised in this way, it will become the water-based coating material which can form the film | membrane with more excellent adhesiveness and heat resistance.

The water-based paint according to the third aspect of the present invention is the water-based paint according to the second aspect of the present invention, wherein at least one of the materials constituting the polyurethane resin fine particles is polycarbonate polyurethane or polyester polyurethane.
If comprised in this way, it will become the water-based coating material which can form the film | membrane excellent in adhesiveness especially.

The water-based paint according to the fourth aspect of the present invention is the water-based paint according to any one of the first to third aspects of the present invention, wherein the polyurethane resin fine particles have an average particle size of 10 to 500 nm. “The average particle diameter is 10 to 500 nm” is not limited to the primary particle diameter, and may be an aggregated particle diameter.
With this configuration, the polyurethane resin fine particles can be easily dispersed in water.
The average particle size is based on particle size distribution measurement by a laser diffraction / scattering method. That is, when the powder is divided into two from a certain particle size by the wet method using the analysis based on the Franhofer diffraction theory and Mie's scattering theory, the larger side and the smaller side are equivalent (volume basis). Was the median diameter.

The water-based paint according to the fifth aspect of the present invention is the water-based paint according to any one of the first to fourth aspects of the present invention described above, wherein the polyurethane resin fine particles include the polyurethane resin fine particles and water. The solid obtained by drying the dispersion liquid has a glass transition point of −80 ° C. to −20 ° C.
If comprised in this way, the film | membrane formed from the aqueous coating material is excellent in a softness | flexibility and adhesiveness.

The water-based paint according to the sixth aspect of the present invention is the water-based paint according to any one of the first to fifth aspects of the present invention, wherein the orthorhombic silicate mineral is: Cordierite and / or mullite.
When configured in this manner, cordierite and / or mullite has a particularly high effect of emitting far infrared rays, and therefore, it becomes an aqueous paint capable of forming a film having a better heat dissipation effect.

The water-based paint according to the seventh aspect of the present invention is the water-based paint according to any one of the first to sixth aspects of the present invention, wherein boron nitride, aluminum nitride, silicon carbide, silica, alumina And a second filler formed of at least one selected from the group consisting of zinc oxide, titanium oxide, titanium black and graphite.
If comprised in this way, since the heat conductivity of the film | membrane formed from the water-based coating material can be improved, the thermal radiation effect of a film | membrane can further be improved.

The water-based paint according to the eighth aspect of the present invention is the water-based paint according to the seventh aspect of the present invention, wherein the first filler and the second filler are added in an amount of 5 to 100 parts by weight based on 100 parts by weight of the polyurethane resin fine particles. 150 parts by weight, the second filler is 1 to 150 parts by weight with respect to 100 parts by weight of the first filler, the first filler and the second filler are powders, and have an average particle size Is 0.01 to 30 μm. The “average particle diameter of 0.01 to 30 μm” is not limited to the primary particle diameter, and may be an aggregated particle diameter.
If comprised in this way, since an average particle diameter is 0.01 micrometer or more, thermal conductivity does not worsen. Further, since the thickness is 30 μm or less, the surface of the formed film is not uneven, the coating liquid is easy to handle, and the adhesion to the substrate is not impaired.

The water-based paint according to the ninth aspect of the present invention is the water-based paint according to any one of the first to eighth aspects of the present invention, wherein the 5% mass loss temperature of the solid after drying is 270 ° C or higher.
If comprised in this way, it will become the water-based paint which can form the film | membrane excellent in heat resistance, and since it can be used in a higher temperature range, it can be used for the member with much calorific value.

The water-based paint according to the tenth aspect of the present invention is the antifoaming agent having foam breaking property or foam-suppressing property in the water-based paint according to any one of the first to ninth aspects of the present invention. including.
If comprised in this way, the water-based coating material which has the effect of destroying the foam once produced | generated (bubble breaking) or suppressing the production | generation of foam (foam suppression) can be obtained.

The heat dissipating member according to the eleventh aspect of the present invention is formed by drying after applying the water-based paint according to any one of the first to tenth aspects of the present invention.
If comprised in this way, the film | membrane (For example, the heat radiating member 10 of FIG. 1) excellent in heat dissipation can be easily formed by drying the water-based paint with easy application | coating. As described above, since the present invention can form a film by drying, film formation is extremely easy even in the case of an aqueous paint, compared to an aqueous paint containing a resin that requires a heat curing step or an active energy ray curing step.

A metal part according to a twelfth aspect of the present invention comprises: a metal part body; and after applying the water-based paint according to any one of the first to tenth aspects of the present invention to the metal part body, A film formed by drying is provided. The “metal component body” may be a metal plate. The “metal part body” may be a heat radiating member, or may be a part of the target product itself.
If comprised in this way, the heat | fever transmitted to the metal component main body will be easily transmitted to a film | membrane, and is further discharge | released as a far infrared ray from a film | membrane.

The metal part according to a thirteenth aspect of the present invention is the metal part according to the twelfth aspect of the present invention, wherein the metal part main body is selected from the group consisting of copper, iron, magnesium, aluminum and alloys thereof. It is formed including at least one kind.
If comprised in this way, since these metals have especially high thermal conductivity, they can improve the heat dissipation effect.

An electronic apparatus according to a fourteenth aspect of the present invention comprises: the metal component according to the twelfth aspect or the thirteenth aspect of the present invention; and an electronic device having a heat generating portion; The electronic device is disposed so as to be in contact with the heat generating portion. The “heat generating part” refers to a part that transfers heat to a metal part.
If comprised in this way, the heat which an electronic device has will be easily transmitted to a metal component, and will be emitted as far infrared rays.

The water-based paint of the present invention is easy to handle because it is water-based, and the film formed from this paint has high heat dissipation and is also excellent in heat resistance and adhesion.

It is sectional drawing of the heat radiating member 14 which consists of the film | membrane 10 and the metal plate 13 which were formed from the water-based paint of this application. In addition, you may use the film | membrane 10 formed from the water-based coating material of this application independently as the heat radiating member 10. FIG. The film 10 includes a first filler 11 and a second filler 12. It is a flowchart which shows the preparation process (S01) of a water-based coating material, and the formation process (S02, S03) of a film | membrane. 2 is a schematic cross-sectional view of an electronic component 30 including a heat dissipation member 14. FIG. It is a figure which illustrates the shape of the metal plate 13 as a heat sink. 1 is a schematic view of a motor 50 in which a heat radiation member 10 is formed on an outer surface 41 of a motor body 40. 1 is a schematic view of a battery 70 in which a heat radiating member 10 is formed on the outer surface of a battery body 60.

This application is based on Japanese Patent Application No. 2013-094439 filed on April 26, 2013 in Japan, the contents of which form part of the present application. The present invention will be more fully understood from the following detailed description. Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, the detailed description and specific examples are preferred embodiments of the present invention and are described for illustrative purposes only. From this detailed description, various changes and modifications will be apparent to those skilled in the art within the spirit and scope of the invention. The applicant does not intend to contribute any of the described embodiments to the public, and modifications and alternatives that may not be included in the scope of the claims within the scope of the claims are also subject to equivalence. As part of the invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same or similar reference numerals, and redundant description is omitted. Further, the present invention is not limited to the following embodiments.

<Water-based paint>
The water-based paint according to the first embodiment of the present invention includes: polyurethane resin fine particles; a first filler formed of an orthorhombic silicate mineral that emits far infrared rays; Water containing dispersed particles and the first filler is included.

≪Polyurethane resin dispersed particles≫
Examples of the polyurethane resin fine particles include at least one particle selected from the group consisting of polycarbonate polyurethane, polyester polyurethane, aliphatic polyurethane, fatty acid-modified polyurethane, aromatic polyurethane, and polyether polyurethane.
Polyurethane is preferable because it is excellent in heat resistance and adhesion to metals, and the above polyurethane is particularly preferable because it can form a film excellent in heat resistance / adhesion. Among these, it is most preferable that polycarbonate polyurethane and / or polyester polyurethane is contained in the constituent elements of the polyurethane resin fine particles.

The average particle diameter of the polyurethane resin fine particles is preferably 10 to 500 nm. More preferably, it is 10 to 100 nm. When the average particle size is 10 nm or more, aggregation in water hardly occurs. Moreover, dispersion | distribution in water is attained as it is 500 nm or less.

The glass transition temperature of a solid obtained by drying a dispersion containing polyurethane resin fine particles and water is preferably −80 to −20 ° C. More preferably, it is −55 to −30 ° C. When the glass transition temperature is −80 ° C. or higher, the coating film strength can be maintained, so that scratches are difficult to occur and the drying property is excellent. When the temperature is −20 ° C. or lower, an effect of preventing cracks can be obtained due to appropriate flexibility. Note that the lower the glass transition temperature, the more preferable the film formed from the water-based paint because the adhesion with other substances (for example, metals) is improved.

≪Orthogonal silicate mineral≫
Examples of the orthorhombic silicate mineral as the first filler include mullite, cordierite, enstatite, hemimorphite, zoisite, sillimanite, and columbite. These fillers are excellent in heat conduction and far-infrared radiation effects, and improve the heat dissipation of a film formed from an aqueous paint. In particular, cordierite and mullite are preferable in that they have a high infrared emission effect, are lightweight and chemically stable, and have a high affinity with resins. The orthorhombic silicate mineral may be either natural or artificial. The water-based paint contains at least one of these fillers. In addition, in terms of storage stability and weather resistance, a filler that has water resistance and is unlikely to undergo hydrolysis is preferable. The crystal system of the silicate mineral used in the present invention is orthorhombic, but in the case of naturally occurring minerals, monoclinic and triclinic minerals, and even cubic minerals May be contained as an impurity. In addition, mica, montmorillonite, graphite (including graphite), kaolin, bentonite, and the like may be included as minerals as long as the effects of the present invention are not significantly impaired. There are no limitations on the method of crystal growth when it is obtained artificially, and known methods can be used. In the case of artificially growing a crystal, it is possible to add a trace amount metal in the range that does not interfere with the far-infrared emission characteristics and expects an effect of increasing the amount of coloring and emission energy.

The second filler may be added in the form of addition to the first filler. The second filler is preferably at least one selected from the group consisting of boron nitride, aluminum nitride, silicon carbide, silica, alumina, zinc oxide, titanium oxide, titanium black and graphite. In particular, boron nitride, alumina, and zinc oxide are preferable because they have high thermal conductivity and can further improve the heat dissipation effect of a film formed from an aqueous paint. Silica is preferable because it can adjust the viscosity of the water-based paint and has an effect of preventing dripping. Titanium oxide is preferably dispersed uniformly in the paint and can be colored white, and titanium black and graphite are preferred because they can be uniformly dispersed in the paint and colored in black to enhance the design. It is also possible to add a plurality of first fillers having different particle sizes instead of the second filler. At this time, the first filler may be the same filler or different.

The shape of the first filler and the second filler is preferably powder, paste, wire shape, or the like. In particular, since a uniform state can be obtained in an aqueous dispersion, it is preferable to mix it in the aqueous paint as a powder. In the case of powder, the average particle size is preferably 0.01 to 30 μm. More preferably, it is 0.05 to 25 μm. More preferably, it is 0.08 to 20 μm. When it is 0.01 μm or more, the viscosity of the water-based paint does not become too high, and the workability of the coating process is good. Further, the thermal conductivity is not deteriorated. When the thickness is 30 μm or less, the surface of the film formed from the water-based paint is not uneven. Also, the sedimentation of the filler is fast and the storage stability of the water-based paint does not deteriorate.
Furthermore, it is preferable to make the average particle diameters of the first filler and the second filler larger than the average particle diameter of the polyurethane resin fine particles because the fillers easily come into contact with each other and the thermal conductivity is improved. In addition, when adding the second filler for coloring purposes, if particles having an average particle size smaller than that of the first filler are used, it is easy to disperse uniformly and does not hinder the contact between the first fillers. The conductivity is preferred without being impaired.

When the total amount of the first filler and the second filler is 5 to 150 parts by weight with respect to 100 parts by weight of the polyurethane resin fine particles, a good heat dissipation effect can be obtained. Considering the work efficiency of the step of applying the water-based paint, the total amount of the first filler and the second filler is preferably 10 to 120 parts by weight with respect to the polyurethane resin fine particles. When the total amount of the filler is 5 parts by weight or more, the heat dissipation characteristics of the filler can be sufficiently obtained. When the amount is 150 parts by weight or less, the viscosity of the paint does not increase so much that the operability is not impaired, and the problem that the filler aggregates in the aqueous paint does not occur. When the second filler is mixed, the second filler is preferably mixed in an amount of 1 to 150 parts by weight with respect to 100 parts by weight of the first filler.

≪Additives≫
A dispersant / antifoaming agent / color pigment / silane coupling agent / surface conditioning agent may be further added to the water-based paint as an additive.
Dispersants include hydroxyl group-containing carboxylic acid esters, long chain polyaminoamide and high molecular weight acid ester salts, high molecular weight polycarboxylic acid salts, long chain polyaminoamide and polar acid ester salts, high molecular weight unsaturated acid esters, Molecular copolymer, modified urea, modified polyurethane, modified polyacrylate, polyether ester type anionic activator, naphthalene sulfonic acid formalin condensate salt, aromatic sulfonic acid formalin condensate salt, polyoxyethylene alkyl phosphate ester, poly Oxyethylene nonyl phenyl ether, polyoxylene monoalkyl ether, and stearylamine acetate are used. By adding 1 to 35 parts by weight with respect to 100 parts by weight of the filler, aggregation of the filler can be prevented, and the storage stability of the aqueous paint can be improved.
Antifoaming agents include silicone-based antifoaming agent, modified silicone-based antifoaming agent, silica-based antifoaming agent, wax, polysiloxane, polyether-modified polydimethylsiloxane, foam-breaking polymer, paraffinic oil, foam-breaking fat Group derivatives and the like. Addition of 0.01 to 5 parts by weight with respect to 100 parts by weight of the water-based paint exhibits antifoaming properties and improves the workability of the water-based paint application process. By adding an antifoaming agent, it is possible to obtain a water-based paint having the effect of destroying the foam once formed (bubble breaking) or suppressing the foam formation (foam suppression). ) Can be improved.
Organic pigments and inorganic pigments can be used as the color pigment. Inorganic pigments are preferred.
A commercially available coupling agent is used for the silane coupling agent. Among these, silane coupling agent Silaace (registered trademark) (S330, S510, S520, S530) manufactured by JNC Corporation is preferable. By adding 1 to 10 parts by weight with respect to 100 parts by weight of the polyurethane resin fine particles, the adhesion between the metal plate and the film formed from the water-based paint can be improved.
Examples of the surface conditioner include organic modified polysiloxane, alkyl modified polysiloxane, acrylic copolymer, surface active polymer, acrylic copolymer, silicon modified acrylic, alcohol alkoxylate and the like. Addition of 0.001 to 10 parts by weight with respect to 100 parts by weight of the water-based paint shows a leveling effect, improved wettability, slip properties, etc., and improves workability and film characteristics of the water-based paint application process.

The water-based paint is prepared by adding the powder of the first filler (and, if necessary, the second filler) to the water dispersion (dispersion liquid) containing the polyurethane resin fine particles. Stirring and defoaming is performed using a stirrer, and the mixture is mixed to such an extent that aggregation of filler is eliminated (FIG. 2, S01). For example, after stirring for 10 minutes at a rotational speed of 2000 rpm, defoaming is performed for 10 minutes at a rotational speed of 2200 rpm.
During mixing, an additive such as a dispersant may be added as necessary, or a second filler may be added to adjust the viscosity of the water-based paint according to the coating method. In order to help disperse the polyurethane resin fine particles in water, a small amount of an organic solvent such as 1-methyl-2-pyrrolidone (NMP) or glycols may be added and mixed.
In addition, what is necessary is just to change suitably the moisture content in the dispersion liquid (dispersion liquid) containing the polyurethane resin microparticles | fine-particles according to the characteristic of resin. That is, the amount may be any amount that can disperse the polyurethane resin fine particles. For example, 40 weight parts or more can be mentioned with respect to 100 weight parts of polyurethane resin fine particles.

As described above, since the water-based paint of the present application uses water as a solvent, it is easier to handle and transport as a paint than an organic solvent. Furthermore, it can also be a measure against VOC (Volatile Organic Compounds / volatile organic compounds). Moreover, since the solvent of the water-based paint of the present invention is water, it can be used on a resin surface that is soluble in an organic solvent. The water-based paint of the present invention can easily form a film having heat dissipation properties by drying after application.

<Heat dissipation member 10>
The heat radiating member according to the second embodiment of the present invention is a film made of the water-based paint according to the first embodiment of the present invention. The film | membrane as the heat radiating member 10 as shown in FIG. 1 can be easily obtained by making it dry after apply | coating an aqueous coating material.

As the method for applying the water-based paint (FIG. 2, S02), it is preferable to use a wet coating method for uniformly coating the water-based paint. Among the wet coating methods, a spin coating method that allows simple and homogeneous film formation is preferable when a small amount is prepared. When productivity is important, gravure coating, die coating, bar coating, reverse coating, roll coating, slit coating, dipping, spray coating, kiss coating, reverse kiss coating, air knife coating Method, curtain coating method, rod coating method and the like are preferable. The wet coating method can be appropriately selected according to the required film thickness, viscosity, drying conditions and the like from these methods.

In addition, it is preferable to apply the water-based paint so that the film thickness after drying is 0.1 to 1000 μm. More preferably, it is 10 to 100 μm, and further preferably 20 to 50 μm. If the thickness is 10 μm or more, the emissivity increases as the thickness increases, and the heat dissipation effect increases. When it is 100 μm or less, the heat transfer coefficient increases as the thickness decreases. Therefore, an appropriate film thickness is selected according to the application.

After coating, the coating film is dried to remove moisture, and the aqueous paint is solidified to form a film (FIG. 3, S03). Drying may be natural drying at room temperature, hot air blowing from a dryer or the like, or heat drying by a machine such as a drying furnace. Drying requires that water be removed to such an extent that the aqueous paint loses fluidity.

The formed film (solid material) contains an orthorhombic silicate mineral having high thermal conductivity and high thermal radiation. Therefore, when a film is formed on a metal having a high thermal conductivity such as that used for a heat sink, the heat radiation from the metal surface can be increased and the temperature of the metal itself can be lowered. A metal such as a heat sink can move the internal heat sufficiently, but if the heat transfer coefficient with the adjacent material is low, it becomes difficult to transfer the heat to the material (for example, air). Therefore, by applying the water-based paint of the present application having high thermal radiation, it is possible to radiate far infrared rays into the atmosphere or the like and efficiently release heat.
Further, the membrane includes a polyurethane resin. Therefore, it is excellent in heat resistance and the mass loss temperature of 5% is 270 ° C. or higher. Furthermore, it has excellent adhesion to the metal surface. Moreover, since it is excellent in ductility, processing after painting is also possible.

As above-mentioned, the film | membrane formed from the water-based coating material of this application functions as a heat radiating member. When a film is formed on a metal or a nonmetal having a lower emissivity than the film, the heat of the metal or the nonmetal is sucked up, converted into far infrared rays, and radiated to the outside to lower the temperature.
For example, the water-based paint of the present application may be applied on the metal component main body and dried to form a metal component having a heat-radiating film. Examples of the metal to be applied include copper, iron, magnesium, aluminum, and alloys thereof. These metals are particularly preferable because of their high thermal conductivity.

As shown in FIG. 1, the metal component main body may be a metal plate 13 having a high thermal conductivity. When the film is formed on the metal plate 13, the heat dissipation member 14 having the metal plate can be formed.
The thickness of the metal plate of the heat radiating member 14 is 0.03 to 100 mm, preferably 0.1 to 10 mm, and more preferably 0.2 to 2 mm. When the heat source is small and the area of the metal plate is sufficiently large, the thicker the heat dissipation effect is. If it is 0.03 mm or more, the heat dissipation effect is excellent. Moreover, it is preferable at a point which is lightweight as it is 100 mm or less.

For example, FIG. 3 is a schematic cross-sectional view of an electronic component 30 as an electronic device in which the heat dissipation member 14 is placed so that the metal plate 13 of the heat dissipation member 14 is in contact with the sealing body 26 of the electronic device 20. Thus, the heat dissipation member 14 is placed on the upper surface of the electronic device 20 and functions. That is, the heat radiating member 14 is placed on the surface of the sealing body 26 and removes heat from the electronic device 20 by releasing heat transmitted from the sealing body 26 to the outside. When the heat radiating member 14 is used in an electronic device such as the electronic device 20, the thickness of the metal plate 13 is 0.01 to 100 mm. The thickness is preferably 0.03 to 10 mm, more preferably 0.1 to 2 mm. The thickness of the film 10 of the heat radiating member 14 is 0.1 to 1000 μm. The thickness is preferably 10 to 100 μm, more preferably 20 to 50 μm. When the heat radiating member 14 is used as a heat radiating plate for an electronic device, a certain amount of thickness is preferable because the heat radiating effect is enhanced.
Moreover, you may affix the heat radiating member 14 so that the surface of the sealing body 26 may be covered. The heat dissipating member 14 covering the entire sealing body 26 can more efficiently release the heat transferred from the inside of the electronic device to the sealing body 26 to the outside.

The heat dissipation member 14 is bonded to the electronic device 20 using an adhesive. The adhesive is preferably an acrylic, silicon, or epoxy adhesive. Alternatively, the heat radiating member 14 may be fixed to the electronic device 20 by using screws or metal fittings. In other words, any metal plate 13 provided in the heat dissipation member 14 may be used as long as it can be fixed to the electronic device 20 in close contact.
FIG. 3 is a usage example of the heat dissipation member 14 in which the film 10 is formed on the flat metal plate 13. However, the shapes of the metal plate 13 and the film 10 are not limited to this, and the area in contact with the outside air may be increased as a shape having a larger surface area.

As shown in FIG. 4, the metal component main body may be an existing metal heat dissipation member such as the heat sink 13. When the film is formed on the surface of the heat sink 13, the performance of the heat sink 13 can be improved (the film 10 is not shown).
In addition, when applying the aqueous paint of this application to the metal plate of the shape as shown in FIG. 4, the metal plate is applied to the aqueous paint adjusted to an appropriate concentration by using an aqueous paint adjusted to have a low viscosity. Paint by dipping method.

The metal part body itself may be part of the product.
For example, as shown in FIG. 5, the metal component main body may be the outer surface of the electric vehicle motor 50. FIG. 5 is a schematic diagram of a motor 50 for an electric vehicle in which a film 10 as a heat radiating member is disposed on the outer surface 41 of the motor body 40 by directly applying and drying the aqueous paint of the present application. The motor body 40 that converts electrical energy into mechanical energy generates heat during operation, and it is necessary to discharge this heat to the outside of the motor. The film 10 functions by being formed on the outer surface 41 of the motor body 40. That is, the film 10 sucks up the heat transmitted from the outer surface 41 of the motor body 40, the heat is transmitted into the film, and further radiated into the outside air as far infrared rays, thereby generating heat generated in the motor body 40. Dissipate heat.
Further, the water-based paint may be applied not only to the outer surface of the motor 50 but also to the inner surface. If it does in this way, the film | membrane formed on the inner surface will function so that the far-infrared rays which generate | occur | produced from the heat source inside the motor 50 may be absorbed from the inside, and also the heat dissipation effect is improved.

Alternatively, the metal component main body may be a metal plate, and the heat radiating member 14 (see FIG. 1) having the metal plate may be placed on the outer surface of the motor main body 40. When the heat radiating member 14 is used in a device such as an electric vehicle motor, the thickness of the metal plate provided in the heat radiating member 14 is usually 0.01 to 100 mm. The thickness is preferably 0.03 to 10 mm, more preferably 0.1 to 2 mm. The film thickness of the heat dissipating member 14 is normally 0.1 to 1000 μm. The thickness is preferably 10 to 100 μm, more preferably 20 to 50 μm. Since the motor of an electric vehicle has a large output and is always rotated during traveling, the motor generates a large amount of heat and is efficiently removed by the heat dissipating member of the present application.
In addition, the heat radiating member of this application is not restricted to the motor for electric vehicles, The use to a general motor is also possible. In particular, the use of the heat dissipating member of the present application is effective when it is desired to make the motor light and small.

The metal part body itself may be part of the product.
For example, as shown in FIG. 6, the metal component main body may be an outer surface of an electric vehicle battery 70 that starts an engine and operates electrical components normally. FIG. 6 is a schematic view of a battery 70 in which a film 10 as a heat radiating member is disposed on the outer surface of the battery body 60 by directly applying and drying the aqueous paint of the present application. The battery main body 60 in which self-heating at the time of charging or discharging becomes a problem needs to discharge the heat to the outside of the battery main body. The film 10 functions by being formed on the outer surface of the battery body 60. That is, the film 10 sucks up heat transferred from the surface of the battery body 60, and the heat is transferred into the film and further radiated to the outside air as far infrared rays, thereby radiating the heat generated in the battery body 60. .
Further, the water-based paint may be applied not only to the outer surface of the battery 70 but also to the inner surface. If it does in this way, the film | membrane formed on the inner surface functions to absorb the heat inside the battery 70 from the inside as far infrared rays, and further enhances the heat dissipation effect.
The battery body 60 may be a battery cell or an assembly thereof.
The battery body 60 may be, for example, an electric vehicle battery that starts an engine and operates electrical components normally.

Alternatively, the metal component main body may be a metal plate, and the heat dissipation member 14 (see FIG. 1) having the metal plate may be placed on the outer surface of the battery main body 60. When the heat radiating member 14 is used in a device such as an electric vehicle battery, the thickness of the metal plate provided in the heat radiating member 14 is usually 0.01 to 100 mm. The thickness is preferably 0.03 to 10 mm, more preferably 0.1 to 2 mm. The film thickness of the heat dissipating member 14 is normally 0.1 to 1000 μm. The thickness is preferably 10 to 100 μm, more preferably 20 to 50 μm.
In addition, the heat radiating member of this application is not restricted to the battery for electric vehicles, You may use for the battery from which the self-heating at the time of charge or discharge becomes a problem.

In addition, the heat radiating members 10 and 14 can also be used for articles such as CPUs and batteries of devices such as smartphones and PCs, batteries, lighting fixtures, machine tools and other self-heating devices, and machines, and provide a high heat dissipation effect.

The heat dissipating member of the present invention has a high heat dissipating effect by a film obtained by drying an aqueous dispersion containing polyurethane resin fine particles and a filler, or by a combination of a film and a metal plate. Moreover, since the heat radiating member and the article can be manufactured by division of labor and the heat radiating member can be easily placed on the article, the manufacturing is easy and the production efficiency can be increased.

Hereinafter, the present invention will be described in detail using examples. However, the present invention is not limited to the contents described in the following examples.

The component material which comprises the heat radiating member used for the Example of this invention is as follows.
<Aqueous polyurethane resin dispersion liquid>
・ Polyester-polyurethane resin dispersion liquid:
PESU1: Sumika Bayer Urethane Co., Ltd. (trade name) Bihydrol UH2342 (containing 1% by weight of 1-methyl-2-pyrrolidone)
PESU2: Sumika Bayer Urethane Co., Ltd. (trade name) Bihydrol UH650
・ Polycarbonate-polyurethane resin dispersion liquid:
PCU1: Sumika Bayer Urethane Co., Ltd. (trade name) Bihydrol UH2606
・ Polyester-polycarbonate-polyurethane resin dispersion liquid:
PECU1: Sumika Bayer Urethane Co., Ltd. (trade name) Bihydrol UHXP2648
PECU2: Sumika Bayer Urethane Co., Ltd. (trade name) Bihydrol UHXP2648 / 1
(Bihydrol is a registered trademark)

The catalog value of the water-based polyurethane resin dispersion liquid used for the Example is shown.

The measured value of the water-based polyurethane resin dispersion liquid used for the Example is shown.

<Comparison resin or resin dispersion liquid>
・ Acrylic resin (water-based): Wasin Paint Co., Ltd. (trade name) Water-soluble glossy varnish
Acrylic resin (thermosetting): Toa Gosei Co., Ltd. (trade name) Aronix M-305
・ Alkyd (polyester) resin (oil-based): Wasin Paint Co., Ltd. (trade name) clear lacquer ・ Epoxy resin (photo-curing): Daicel (trade name) Celoxide 2021P
<Filler>
Synthetic cordierite: Marusu glaze joint stock company (trade name) SS-200 (average particle size 7.5 μm) SS-1000 (average particle size 1.7 μm) SS-5000 (average particle size 0.6 μm)
Boron nitride: Denkaboron nitride (trade name) SGP, Electrochemical Industry
・ Silicon dioxide (silica): Fuji Silysia Co., Ltd. (trade name) Silicia ・ Aluminum oxide (alumina): Showa Denko Co., Ltd. (trade name) AL-47H
・ Titanium oxide: Ishihara Sangyo Co., Ltd. (trade name) Taipei CR-50
・ Silicon carbide: Sigma-Aldrich Japan (trade name) Silicon carbide
・ Graphite: Nihon Graphite Industry Co., Ltd. (trade name) scale-like graphite powder F # 2
・ Titanium Black: 13M-C, manufactured by Mitsubishi Materials Corporation
(Aronix, Celoxide, Denkaboron Nightride, and Taipei are registered trademarks)
<Cation generator>
・ CPI-210S: Sun Apro Co., Ltd.

<Measurement method of particle size distribution>
The average particle diameter (median diameter) of each particle was measured using a laser diffraction scattering type particle size distribution measuring apparatus LA-950V2 manufactured by Horiba. That is, using the analysis based on the Franchoffer diffraction theory and Mie's scattering theory, when measuring by a wet method and dividing the powder into two from a certain particle size, the larger side and the smaller side are equivalent (volume basis) ) Is the median diameter. The measurement was performed using a wet method, a solution in which a sample was dispersed after adding a small amount of a measurement sample (about one earpick) in pure water and then treating in an ultrasonic cleaner for 3 minutes. The concentration of the slurry at the time of measurement was adjusted so that the laser transmittance was 80%.

<Sample preparation>
Using an autorotation / revolution mixer (Shinky Awatori Rentaro ARE250), the aqueous polyurethane resin dispersion liquid and filler powder were stirred for 10 minutes at a rotational speed of 2000 rpm, and then defoamed for 10 minutes at a rotational speed of 2200 rpm. As a result, the following samples were prepared.

Example 1
100 parts by weight and 15 parts by weight of PESU1 and synthetic cordierite (SS-1000) with an average particle size of 1.7 μm were weighed, put into a polypropylene container, and mixed by a rotating / revolving mixer. The sample of Example 1 was obtained.
<< Example 2 >>
100 parts by weight and 21.4 parts by weight of PESU2 and synthetic cordierite (SS-1000) with an average particle size of 1.7 μm were weighed and placed in a polypropylene container, and mixed with a rotating / revolving mixer. A sample of Example 2 was obtained.
<< Examples 3 to 5 >>
Samples of Examples 3 to 5 were prepared in the same manner as in Example 1 except that the type of the aqueous polyurethane resin dispersion liquid was different.
≪Comparative example 1≫
Acrylic resin (water-based) paint and synthetic cordierite (SS-1000) with an average particle size of 1.7 μm are weighed in 100 parts by weight and 15 parts by weight, respectively, and placed in a polypropylene container. The sample of Comparative Example 1 was mixed.
≪Comparative example 2≫
100 parts by weight and 42.9 parts by weight of acrylic resin (thermosetting) and synthetic cordierite (SS-1000) with an average particle size of 1.7 μm were weighed and placed in a polypropylene container. The sample was mixed with a revolution mixer to obtain a sample of Comparative Example 2.
«Comparative Example 3»
100 parts by weight and 15.9 parts by weight of alkyd resin paint (oil-based) and synthetic cordierite (SS-1000) with an average particle size of 1.7 μm are weighed and put into a polypropylene container. The sample of Comparative Example 3 was prepared by mixing with a mixer.
<< Comparative Example 4 >>
Epoxy resin (photocurable), synthetic cordierite (SS-200) having an average particle diameter of 7.5 μm, methyl ethyl ketone (MEK), and CPI-210S were respectively 70 parts by weight, 30 parts by weight, 30 parts by weight, 0 parts. .3 parts by weight were weighed, placed in a polypropylene container, and mixed by a rotation / revolution mixer to obtain a sample of Comparative Example 4.

Example 6
100 parts by weight and 35 parts by weight of PECU 1 and synthetic cordierite (SS-1000) with an average particle diameter of 1.7 μm were weighed, put into a polypropylene container, and mixed by a rotating / revolving mixer. The sample of Example 6 was obtained.
<< Comparative Examples 5 and 6 >>
Samples of Comparative Examples 5 and 6 were used in the same manner as in Example 6 except that the type of filler was different.
<< Comparative Example 7 >>
Only PECU1 was used as a sample.
«Comparative Example 8»
Only black alumite treatment was used (in the following [1. Evaluation of heat radiation characteristics], one side of the aluminum plate used was treated with black alumite).

<< Examples 7 to 27 >>
Furthermore, in order to adjust the color and enhance the heat dissipation effect, an average particle size of 7.5 μm cordierite (SS-200) and a second filler were added as the first filler. The ratio of the addition amount of the aqueous polyurethane resin dispersion and the filler is shown below. The sample preparation procedure is the same as in Example 6. In Examples 7, 14, and 21, cordierite having a particle size different from that of the first filler is used in combination, and the second filler is not included. Cordierite with different particle diameters is described in the filler column.
<< Comparative Examples 9 to 11 >>
Alumina was added as the first filler and titanium oxide was added as the second filler. The ratio of the addition amount of the aqueous polyurethane resin dispersion liquid and the additional filler is shown below. The sample preparation procedure is the same as in Example 6.

[1. Evaluation of heat dissipation characteristics]
About an Example and a comparative example, evaluation of the thermal radiation characteristic is shown.
[1-1 Preparation of heat dissipation member]
Using a spin coater, each sample of the example and the comparative example was applied to an aluminum plate having a thickness of 40 mm × 40 mm and a thickness of 0.4 mm. The rotation speed of the spin coater was adjusted so that the coating films of the respective examples and comparative examples were about 30 μm. The film thickness was measured using a DIGIMICRO MFC-101A manufactured by Nikon.
Heating was performed at 130 degrees for 3 minutes using a hot plate, and the applied samples of Examples and Comparative Examples were dried to form a heat dissipation member having an aluminum plate.
The heat radiating member according to Comparative Example 2 is a heat radiating member having an aluminum plate prepared by applying the prepared sample by spin coating on an aluminum plate having a thickness of 40 × 40 mm and a thickness of 0.4 mm, followed by curing with a 190 ° hot plate. Formed.
The heat radiating member according to Comparative Example 4 was prepared by applying the prepared sample to an aluminum plate having a thickness of 40 mm × 40 mm by spin coating, followed by curing with an ultraviolet irradiator to form a heat radiating member having an aluminum plate. did.
The heat dissipating member according to Comparative Example 7 is one in which only PECU 1 is applied to an aluminum plate and then dried. The heat radiating member according to Comparative Example 8 does not have a resin and is obtained by performing black alumite treatment on one side of an aluminum plate.

[1-2 Evaluation of heat dissipation characteristics I]
The aluminum surface side of the heat radiating member and a transistor (silicon NPN triple diffusion type 2SD2012 manufactured by Toshiba Transistor) were bonded together using a double-sided tape (thermal conductive adhesive transfer tape No. 9885 manufactured by Sumitomo 3M Co., Ltd.). A K thermocouple (ST-50 manufactured by Rika Kogyo Co., Ltd.) was attached to the back side of the surface to which the heat radiating member of the transistor was bonded, and the temperature was recorded with a personal computer using a data logger. The heat dissipating member to which this transistor is attached is left in the center of a thermostatic chamber set at 40 ° C., and after confirming that the temperature of the transistor has become constant at 40 ° C., a 1.18 V voltage is applied to the transistor using a DC stabilized power supply. Was applied, and the temperature change of the transistor surface was measured.

Heat radiating members were prepared using the samples of Examples 1 to 5 and Comparative Examples 1 to 4, and their heat radiating characteristics were evaluated. The evaluation results are shown below.

From the results shown in Table 7, it can be seen that the heat dissipating members using the aqueous paints of Examples 1 to 5 of the present invention have excellent heat dissipating properties as compared with Comparative Examples 1 to 4. Further, from the results of the heat dissipation test using the water-based paints of Examples 1 to 5, the type of resin is particularly preferably polycarbonate-polyurethane, polyester-polyurethane, or polyester-polycarbonate-polyurethane.

[1-3 Evaluation of heat dissipation characteristics II]
The metal surface side of the heat dissipating member and the ceramic heater (Sakaguchi Electric Heat Co., Ltd. micro ceramic heater MS-3) were bonded together using a double-sided tape (Sumitomo 3M Co., Ltd. heat conductive adhesive transfer tape No. 9885). . A K thermocouple (ST-50 manufactured by Rika Kogyo Co., Ltd.) was attached to the back surface of the surface to which the heat radiating member of the ceramic heater was bonded, and the temperature was recorded with a personal computer using a data logger. The heat dissipating member attached with this heater is placed in the center of a thermostatic chamber set at 40 ° C., and after confirming that the temperature of the ceramic heater is constant at 40 ° C., the ceramic heater is 14V using a DC stabilized power supply. Was applied, and the temperature change of the ceramic heater surface was measured. Since the ceramic heater generates a certain amount of heat, the higher the heat dissipation effect of the attached heat dissipation member, the lower the temperature of the ceramic heater. That is, it can be said that the heat dissipation member having a lower temperature of the ceramic heater has a higher heat dissipation effect.

Heat radiating members were prepared using the samples of Examples 6 to 27 and Comparative Examples 5 to 11, and their heat radiating characteristics were evaluated. The evaluation results are shown below.

From the results shown in Table 8, it can be seen that the heat dissipating member using the water-based paint of the present invention has an excellent heat dissipating property. From the results shown in Table 9, the heat dissipating member using the water-based paint of the present invention does not impair the heat dissipating performance even when the second filler is added. In particular, boron nitride and alumina have high thermal conductivity. This is preferable because the heat dissipation effect of the film formed from the aqueous paint can be further improved. Titanium oxide is preferable because it can be uniformly dispersed in the coating and the coating can be colored white. Titanium black is preferable because it can be uniformly dispersed in the coating and the coating can be colored black.

[2. Evaluation of film properties]
About an Example and a comparative example, evaluation of a film physical property is shown. [2. Samples used in the evaluation of film properties] are [1. This is the same as that used in the evaluation of heat dissipation characteristics.

[2-1 Evaluation of heat resistance]
The sample was poured into an aluminum cup and dried at room temperature for 24 hours. The thickness of the coating film was adjusted to 1 mm after drying. The coating film was cut out, and the 5% mass loss temperature of the coating film was measured using a differential thermothermal gravimetric simultaneous measurement apparatus EXSTAR TG / DTA6000 series (manufactured by SII Nanotechnology Co., Ltd.).

From the above results, it can be seen that the coating film made of the aqueous paint of the present invention has excellent heat resistance. For this reason, use in a higher temperature range is possible. Further, when Example 1 containing a co-solvent is compared with Examples 2 to 5 not containing a co-solvent, those containing no co-solvent are preferable. Examples 2 to 5 and Comparative Examples 1, 3 and 4 are In comparison, Examples 2-5 are preferred, with the polyester-polyurethane of Example 2, the polycarbonate-polyurethane of Example 3 or the polyester-polycarbonate-polyurethane of Examples 4 and 5 being particularly preferred. In addition, the thermosetting acrylic paint cured film (Comparative Example 2) has excellent heat resistance, but is not preferable because the volumetric shrinkage due to heating is large and cracks are removed from the substrate.

[2-2 Evaluation of coating film adhesion]
A sample was applied to each of an aluminum plate having a thickness of 0.4 mm, a copper plate having a thickness of 0.4 mm, a magnesium plate having a thickness of 1.2 mm, and a stainless steel plate having a thickness of 0.2 mm using a spin coater, and the coating was performed at 130 ° C. for 3 minutes. Heat dried. The thickness of the coating film was adjusted to 30 μm after drying. The adhesion test was performed in accordance with JIS-K5600-5-6 with a 100 × 10 incision of 10 × 10, and using TQC ISO Adhesive Tape / STANDARD (manufactured by Cortec Co., Ltd.) Judged. The case where no separation occurred was marked with ◎, the case where the number of cells not peeled off was 90 squares or more, ◯, the case where 70 squares or more and less than 90 squares, Δ, and the case where it was less than 70 squares, x.

The results of the adhesion test of the formed coating films using the samples prepared in Examples 2 to 4 and Comparative Examples 1 to 4 are shown below.

From the above results, it can be seen that all the coating films made of the aqueous paint of the present invention have excellent substrate adhesion. Polycarbonate-polyurethane and polyester-polyurethane coatings are particularly preferred because they have excellent adhesion to any substrate. Since the adhesiveness with the base material is excellent, heat is efficiently transmitted from the heat generating portion, and high heat dissipation performance can be obtained.

[2-3 Evaluation of bending resistance]
The results of a bending resistance test of the formed coating films using the samples prepared in Examples 2 to 4 and Comparative Examples 1 to 4 are shown below. A sample was coated on a 0.4 mm thick aluminum plate with a spin coater and dried by heating at 130 ° C. for 3 minutes. The thickness of the coating film was adjusted to 30 μm after drying. In the bending resistance test, when the aluminum plate was bent 90 degrees with the coating surface facing outward, the coating film could not be cracked, and the cracked coating was rated as x.

From the above results, it can be seen that the coating film made of the water-based paint of the present invention has very excellent bending resistance in any of Examples 2 to 4. For this reason, it is possible to perform punching or bending after coating on the substrate.

[2-4 Evaluation of scratch hardness]
The results of evaluating the coating film hardness of the formed coating film using the samples prepared in Examples 2 to 4 are shown below. A sample was coated on a 0.4 mm thick aluminum plate with a spin coater and dried by heating at 130 ° C. for 3 minutes. The thickness of the coating film was adjusted to 30 μm after drying. The scratch hardness test method conformed to JIS-K-5-4.

From the above results, it can be seen that the polycarbonate-polyurethane of Example 3 and the polyester-polycarbonate-polyurethane of Example 4 have excellent scratch hardness despite having flexibility. For this reason, it is hard to be damaged. In addition, the coating film made of the water-based paint of the present invention is excellent as an exterior paint since the scratches once alleviated and the scratches are not noticeable. About a thermosetting acrylic paint cured film (comparative example 2), although scratch hardness is excellent, since adhesiveness with a base material is weak and peels off from a base material, it is unpreferable.

It is possible to adjust film physical properties such as adhesion, hardness, and bending strength of the coating film by preparing a coating composed of various polyurethane resin dispersion liquids and fillers.

[3. Evaluation of paint properties]
The physical properties of paints composed of various polyurethane resin dispersions and fillers are evaluated. [3. The samples used in [Evaluation of paint properties] are [1. This is the same as that used in the evaluation of heat dissipation characteristics.

<< Example 28 >>
PESU2, PECU1, and synthetic cordierite (SS-1000) with an average particle size of 1.7 μm were weighed in 75 parts by weight, 25 parts by weight, and 19.8 parts by weight, respectively, and placed in a polypropylene container for rotation. -It mixed with the revolution mixer and it was set as the sample of Example 28.
<< Examples 29 to 33 >>
Samples of Examples 29 to 33 were prepared in the same manner as in Example 28 except that the type of the aqueous polyurethane resin dispersion liquid and the mixing ratio of the aqueous polyurethane resin dispersion liquid and the filler were different.

[3-1 Evaluation of heat resistance]
The heat resistance of the coating films formed using the samples of Examples 28 to 33 was evaluated in the same procedure as in [2-1 Evaluation of heat resistance].

From the above results, it can be seen that the coating film made of the aqueous paint of the present invention has high heat resistance. For this reason, use in a higher temperature range is possible. In addition, Examples 28 to 33 show that the heat resistance can be improved by adding the polyester-polyurethane.

[3-2 Evaluation of coating film adhesion]
The adhesion of the coating films formed using the samples of Examples 28 to 33 was evaluated in the same procedure as [2-2 Evaluation of coating film adhesion] using an aluminum plate having a thickness of 0.4 mm. . In addition, the case where it did not peel at all was marked as ◎, the case where the number of cells not peeled off was 90 squares or more, ◯, the case where it was 70 squares or more and less than 90 squares, and the case where it was less than 70 squares.

From the above results, it can be seen that the coating film made of the aqueous paint of the present invention is excellent in adhesion. Further, it is preferable to add 25% or more of polycarbonate-polyurethane having a low glass transition point and good adhesion to the coating material because the adhesion between the substrate and the coating film is further improved. By mixing the polyurethane resin fine particles, the characteristics of each polyurethane coating film can be expressed.

[3-3 Evaluation of bending resistance]
The bending resistance of the coating films formed using the samples of Examples 28 to 33 was evaluated in the same procedure as in [2-3 Evaluation of bending resistance].

From the above results, it can be seen that the coating film made of the water-based paint of the present invention has very excellent bending resistance in any of Examples 28 to 33. For this reason, it is possible to perform punching or bending after coating on the substrate.

[3-4 Evaluation of scratch hardness]
The scratch hardness of the coating film formed using the samples of Examples 28 to 33 was evaluated by the same procedure as [2-4 Evaluation of scratch hardness].

From the above results, it can be seen that the coating film made of the water-based paint of the present invention has excellent scratch hardness despite having excellent bending resistance. For this reason, it is hard to be damaged. Further, it is preferable to add 50% or more of polycarbonate-polyurethane because scratch hardness is further improved and scratches are hardly formed. In addition, the coating film made of the water-based paint of the present invention is excellent as an exterior paint since the scratches once alleviated and the scratches are not noticeable.

[4. Evaluation of paint properties]
By adding various additives such as a dispersant and an antifoaming agent to a paint composed of various polyurethane resin dispersion liquids and fillers, it is possible to improve the handling and storage stability of the paint.
The evaluation about the physical property of the coating material which consists of various polyurethane resin dispersion liquid, a filler, and an additive is shown. [4. The component materials constituting the sample used in the evaluation of paint physical properties are as follows.
<Dispersant>
・ High molecular weight acidic polymer alkylol ammonium salt solution: Big Chemie Japan Co., Ltd. (trade name) ANTI-TERRA-250
Pigment affinity high molecular weight block copolymer: Big Chemie Japan Co., Ltd. (trade name) DISPERBYK-190
Pigment affinity copolymer: Big Chemie Japan Co., Ltd. (trade name) DISPERBYK-191
Pigment affinity copolymer: Big Chemie Japan Co., Ltd. (trade name) DISPERBYK-194N
Pigment affinity copolymer: Big Chemie Japan Co., Ltd. (trade name) DISPERBYK-199
Pigment affinity acrylic copolymer: Big Chemie Japan Co., Ltd. (trade name) DISPERBYK-2012
(ANTI-TERRA and DISPERBYK are registered trademarks)
<Antifoaming agent>
-Bubble-breaking polymer / hydrophobic particle mixture: Big Chemie Japan Co., Ltd. (trade name) BYK-1710

<< Example 34 >>
100 parts by weight, 15 parts by weight, and 1.72 parts by weight of PECU 1, synthetic cordierite (SS-1000) having an average particle diameter of 1.7 μm, and ANTI-TERRA-250 were respectively measured, and a container made of polypropylene. And mixed with a rotation / revolution mixer to obtain a sample of Example 34.
<< Examples 35 to 40 >>
Samples of Examples 35 to 40 were prepared in the same manner as in Example 34 except that the types and amounts of additives were different.

[4-1 Effects of dispersant]
An evaluation result is shown below about the effect of the dispersing agent for preventing sedimentation of a filler. To confirm the dispersion effect, 30 g of the samples of Examples 34 to 39 and Example 4 were filled in a 50 ml glass sample bottle and allowed to stand for 5 days, and then the glass sample bottle was shaken up and down by hand and immediately after the start of shaking. The filler was redispersed in less than 3 minutes, and the filler was redispersed in 3 minutes or more and less than 10 minutes was evaluated as Δ.

ANTI-TERRA-250 was a rheology control agent, and the sedimentation rate of the filler could be reduced, but the filler could not be redispersed by shaking. From this, it is considered that ANTI-TERRA-250 can reduce the sedimentation rate of the filler when used in combination with other dispersants. DISPERBYK-191 and DISPERBYK-2012 were able to reduce the amount of filler that settled, but took some time to disperse by shaking. From this, it was found that dispersion was possible up to a filler having a relatively large particle size. With DISPERBYK-199, the amount of filler that settled was almost the same as that without additive, but the filler was easily dispersed by shaking. From this, it was found that it is effective to prevent the fillers from aggregating.
On the other hand, DISPERBYK-190 had almost no effect, and DISPERBYK-194N had polyurethane resin fine particles precipitated or aggregated immediately after addition. This is because the acid value of DISPERBYK-194N is larger than that of other dispersants, and the pH of the dispersion is increased by the addition. By selecting a dispersant suitable for the coating material of the present invention, it becomes possible to disperse the filler effectively, and the heat dissipation performance can be effectively expressed.
[4-2 Effect of antifoaming agent]
Described below are further improved embodiments of the present invention. Although the water-based paint of Example 4 showed a sufficient heat dissipation effect, Example 40 (see Table 19), which was an embodiment in which an antifoaming agent was added, was produced in order to give a further adhesion effect to the aluminum plate. . In Example 40, the defoaming effect is higher than in Example 4, and the adhesion (film forming property of the coating film) is further excellent. That is, when the filler is precipitated in the water-based paint, it is effective to add an antifoaming agent when it is necessary to disperse the filler again by shaking and stirring the paint. The test was conducted as follows.
30 g of the sample of Example 40 and Example 4 was packed in a 50 ml glass sample bottle, shaken for 3 minutes by shaking the glass sample bottle up and down by hand, and left for 10 minutes immediately after the end of shaking to check for the presence of bubbles. confirmed. In addition, for evaluation of film formability, 30 μm of a coating material that was allowed to stand for 10 minutes after shaking on an aluminum plate having a thickness of 0.4 mm was formed, and the appearance of unevenness in the coating film was observed.
In the paint to which BYK-1710 of Example 40 was added, no macro bubbles were generated after shaking, and it was confirmed that all the micro bubbles generated slightly disappeared after 10 minutes. In addition, there was no unevenness or repellency due to bubbles during film formation, and a uniform film could be formed.
[4-3 Evaluation of heat dissipation characteristics]
Using the coated aluminum plate produced in [4-2 Effect of antifoaming agent] using the sample of Example 40 as a heat radiating member, the aluminum surface side and the transistor (Toshiba Transistor's silicon NPN triple diffusion type 2SD2012) are double-sided tape (The Sumitomo 3M Co., Ltd. product heat conductive adhesive transcription | transfer tape No.9885) bonded together. A K thermocouple (ST-50 manufactured by Rika Kogyo Co., Ltd.) was attached to the back side of the surface to which the heat radiating member of the transistor was bonded, and the temperature was recorded with a personal computer using a data logger. The heat dissipating member to which this transistor is attached is left in the center of a thermostatic chamber set at 40 ° C., and after confirming that the temperature of the transistor has become constant at 40 ° C., a 1.18 V voltage is applied to the transistor using a DC stabilized power supply. Was applied, and the temperature change of the transistor surface was measured. The evaluation results are shown below.

From the results shown in Table 21, it can be seen that the heat dissipating member using the water-based paint of Example 40 of the present invention has substantially the same heat dissipating property as that of Example 4. From this, it can be seen that the antifoaming agent does not adversely affect the heat dissipation characteristics. Rather, it is possible to avoid such risks by adding defoaming agents, as bubbles may be formed in the coating film or unevenness may occur in the coating film due to bubbles, which may adversely affect the heat dissipation characteristics. can do.

All publications, including publications, patent applications and patents cited herein are specifically incorporated by reference with reference to each reference individually, and the entire contents thereof are described herein. To the same extent, reference here is incorporated.

The use of nouns and similar directives used in connection with the description of the invention (especially in connection with the claims below) is not specifically pointed out herein or clearly contradicted by context. , And construed to cover both singular and plural. The phrases “comprising”, “having”, “including” and “including” are to be interpreted as open-ended terms (ie, including but not limited to), unless otherwise specified. The use of numerical ranges in this specification is intended only to serve as a shorthand for referring individually to each value falling within that range, unless otherwise indicated herein. Each value is incorporated into the specification as if it were individually listed herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. Any examples or exemplary phrases used herein (eg, “etc.”) are intended only to better describe the invention, unless otherwise stated, and to limit the scope of the invention. is not. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

In this specification, preferred embodiments of the present invention are described, including the best mode known to the inventors for carrying out the invention. Variations of these preferred embodiments will become apparent to those skilled in the art after reading the above description. The present inventor expects skilled workers to apply such modifications as appropriate, and intends to implement the present invention in a manner other than that specifically described herein. . Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

DESCRIPTION OF SYMBOLS 10 Heat radiating member, film | membrane 11 1st filler 12 2nd filler 13 Metal plate 14 Heat radiating member 20 which has a metal plate Electronic device 21 Glass substrate 22 Anode 23 Electroluminescent layer 24 Cathode 25 Desiccant 26 Sealing body 27 Adhesive 30 Electronic component 40 Motor body 41 Outer surface 50 Motor 60 Battery body 70 Battery

Claims (14)

1. Polyurethane resin fine particles;
   A first filler formed of an orthorhombic silicate mineral that emits far infrared radiation;
   Including water in which the polyurethane resin fine particles and the first filler are dispersed;
   Water-based paint.
2. The material constituting the polyurethane resin fine particles is at least one selected from the group consisting of polycarbonate polyurethane, polyester polyurethane, aliphatic polyurethane, fatty acid-modified polyurethane, aromatic polyurethane, and polyether polyurethane.
   The water-based paint according to claim 1.
3. At least one of the materials constituting the polyurethane resin fine particles is polycarbonate polyurethane or polyester polyurethane.
   The water-based paint according to claim 2.
4. The polyurethane resin fine particles have an average particle size of 10 to 500 nm.
   The water-based paint according to any one of claims 1 to 3.
5. The polyurethane resin fine particles have a glass transition point of −80 ° C. to −20 ° C., which is obtained by drying a dispersion of the polyurethane resin fine particles and water.
   The water-based paint according to any one of claims 1 to 4.
6. The orthorhombic silicate mineral is cordierite and / or mullite.
   The water-based paint according to any one of claims 1 to 5.
7. A second filler formed of at least one selected from the group consisting of boron nitride, aluminum nitride, silicon carbide, silica, alumina, zinc oxide, titanium oxide, titanium black and graphite;
   The water-based paint according to any one of claims 1 to 6.
8. Containing 5 to 150 parts by weight of the first filler and the second filler with respect to 100 parts by weight of the polyurethane resin fine particles;
   The second filler is 1 to 150 parts by weight with respect to 100 parts by weight of the first filler,
   The first filler and the second filler are powders and have an average particle size of 0.01 to 30 μm.
   The water-based paint according to claim 7.
9. The 5% mass loss temperature of the solid after drying is 270 ° C. or higher.
   The water-based paint according to any one of claims 1 to 8.
10. Including an antifoaming agent having foam-breaking property or foam-reducing property,
    The water-based paint according to any one of claims 1 to 9.
11. A water-based paint according to any one of claims 1 to 10 is applied and then dried.
    Heat dissipation member.
12. With metal parts body;
    A film formed by applying the water-based paint according to any one of claims 1 to 10 to the metal component main body and then drying the coating;
    Metal parts.
13. The metal component body is formed to include at least one selected from the group consisting of copper, iron, magnesium, aluminum, and alloys thereof.
    The metal part according to claim 12.
14. A metal part according to claim 12 or claim 13;
    An electronic device having a heat generating part;
    A metal component body of the metal component is disposed in the electronic device so as to contact the heat generating portion;
    Electronics.
    

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